Title:
Printhead assembly for a print on demand digital camera system
Kind Code:
A1


Abstract:
A printhead assembly for a camera system that includes an ink reservoir assembly that is mountable on the chassis of the camera system and defines at least three ink reservoirs in which differently colored inks are received. The ink reservoir assembly defines an outlet. A guide assembly is positioned in the ink reservoir assembly to define three discrete ink paths that open at the outlet. A printhead integrated circuit is positioned in the outlet to span the printing path. The printhead integrated circuit defines three sets of inlet apertures, each set of inlet apertures being aligned with a respective ink path.



Inventors:
Silverbrook, Kia (Balmain, AU)
Application Number:
10/729157
Publication Date:
06/24/2004
Filing Date:
12/08/2003
Assignee:
Silverbrook Research Pty Ltd (Balmain, AU)
Primary Class:
Other Classes:
348/E5.024, 348/E5.055
International Classes:
B41J2/14; B41J2/16; B41J2/175; B41J3/36; B41J3/42; B41J3/44; B41J11/00; B41J11/70; B41J15/04; B42D15/10; G06F1/16; G06F21/00; G06K1/12; G06K7/14; G06K19/06; G06K19/073; G07F7/08; G07F7/12; G11C11/56; H04N1/21; H04N1/32; H04N5/225; H04N5/262; B41J2/165; H04N1/00; (IPC1-7): H04N5/225
View Patent Images:



Primary Examiner:
MISLEH, JUSTIN P
Attorney, Agent or Firm:
SILVERBROOK RESEARCH PTY LTD (BALMAIN, AU)
Claims:

We claim:



1. A printhead assembly for a camera system having a chassis and a platen assembly that is mountable on the chassis, the platen assembly being configured to support passage of a print medium along a printing path, the printhead assembly comprising an ink reservoir assembly that is mountable on the chassis and defines at least three ink reservoirs in which respective differently colored inks are received, the ink reservoir assembly defining an outlet; a guide assembly that is positioned in the ink reservoir assembly to define at least three discrete ink paths that open at the outlet; and at least one printhead integrated circuit that is positioned in the outlet to span the printing path, the, or each, printhead integrated circuit defining at least three sets of inlet apertures, each set of inlet apertures being aligned with a respective ink path.

2. A printhead assembly as claimed in claim 1, in which the ink reservoir assembly defines three ink reservoirs and the guide assembly defines three discrete ink paths.

3. A printhead assembly as claimed in claim 2, in which both the ink reservoir assembly and the guide assembly are elongate to span the printing path, the ink reservoir assembly including an elongate base member and an elongate cover member, the cover member having a roof wall, a pair of opposed side walls and a pair of spaced inner walls, the side walls and the inner walls depending from the roof wall and being generally parallel to each other and the base member having a floor and a pair of opposed end walls and defining an elongate opening in which the printhead integrated circuits are mounted, the guide assembly being interposed between lower ends of the inner walls and the floor.

4. A printhead assembly as claimed in claim 3, in which the guide assembly includes a pair of guide walls that extend from respective lower ends of the inner walls inwardly towards the elongate opening to define the three distinct ink paths that terminate at respective sets of inlet apertures of the printhead integrated circuits.

5. A printhead assembly as claimed in claim 3, in which the base member, the cover member and the guide assembly are molded of a plastics material.

6. A printhead assembly as claimed in claim 3, in which one of the end walls defines a number of air inlet openings that are treated to be hydrophobic to permit the ingress of air into the ink reservoirs as ink is fed from the ink reservoirs and to inhibit the egress of ink.

7. A printhead assembly as claimed in claim 1, in which a sponge-like member is positioned in each ink reservoir to store the ink while inhibiting agitation of ink during general use of the camera system.

8. A camera system that includes a printhead assembly as claimed in claim 1.

Description:

[0001] This is a Continuation application of U.S. Ser. No. 09/112,774 filed on Jul. 10, 1998

FIELD OF THE INVENTION

[0002] The present invention relates substantially to the concept of a disposable camera having instant printing capabilities and in particular, discloses a printhead assembly for a digital camera system.

BACKGROUND OF THE INVENTION

[0003] Recently, the concept of a “single use” disposable camera has become an increasingly popular consumer item. Disposable camera systems presently on the market normally include an internal film roll and a simplified gearing mechanism for traversing the film roll across an imaging system including a shutter and lensing system. The user, after utilizing a single film roll returns the camera system to a film development center for processing. The film roll is taken out of the camera system and processed and the prints returned to the user. The camera system can then be re-manufactured through the insertion of a new film roll into the camera system, the replacement of any worn or wearable parts and the re-packaging of the camera system in accordance with requirements. In this way, the concept of a single use “disposable” camera is provided to the consumer.

[0004] Recently, a camera system has been proposed by the present applicant which provides for a handheld camera device having an internal print head, image sensor and processing means such that images sense by the image sensing means, are processed by the processing means and adapted to be instantly printed out by the printing means on demand. The proposed camera system further discloses a system of internal “print rolls” carrying print media such as film on to which images are to be printed in addition to ink to supplying the printing means for the printing process. The print roll is further disclosed to be detachable and replaceable within the camera system.

[0005] Unfortunately, such a system is likely to only be constructed at a substantial cost and it would be desirable to provide for a more inexpensive form of instant camera system which maintains a substantial number of the quality aspects of the aforementioned arrangement.

[0006] It would be further advantageous to provide for the effective interconnection of the sub components of a camera system.

SUMMARY OF THE INVENTION

[0007] According to a first aspect of the invention, there is provided a printhead assembly for a camera system having a chassis and a platen assembly that is mountable on the chassis, the platen assembly being configured to support passage of a print medium along a printing path, the printhead assembly comprising

[0008] an ink reservoir assembly that is mountable on the chassis and defines at least three ink reservoirs in which differently colored inks are received, the ink reservoir assembly defining an outlet;

[0009] a guide assembly that is positioned in the ink reservoir assembly to define at least three discrete ink paths that open at the outlet; and

[0010] at least one printhead integrated circuit that is positioned in the outlet to span the printing path, the, or each, printhead integrated circuit defining at least three sets of inlet apertures, each set of inlet apertures being aligned with a respective ink path.

[0011] The ink reservoir assembly may define three ink reservoirs and the guide assembly may define three discrete ink paths.

[0012] Both the ink reservoir assembly and the guide assembly may be elongate to span the printing path. The ink reservoir assembly may include an elongate base member and an elongate cover member, the cover member having a roof wall, a pair of opposed side walls and a pair of spaced inner walls, the side walls and the inner walls depending from the roof wall and being generally parallel to each other and the base member having a floor and a pair of opposed end walls and defining an elongate opening in which the printhead integrated circuits are mounted, the guide assembly being interposed between lower ends of the inner walls and the floor.

[0013] The guide assembly may include a pair of guide walls that extend from respective lower ends of the inner walls inwardly towards the elongate opening to define the three distinct ink paths that terminate at respective sets of inlet apertures of the printhead integrated circuits.

[0014] The base member, the cover member and the guide assembly may be molded of a plastics material.

[0015] One of the end walls may define a number of air inlet openings that are treated to be hydrophobic to permit the ingress of air into the ink reservoirs as ink is fed from the ink reservoirs and to inhibit the egress of ink.

[0016] A sponge-like member may be positioned in each ink reservoir to store the ink while inhibiting agitation of ink during general use of the camera system.

[0017] The invention extends to a camera system that includes a printhead assembly as described above.

[0018] In accordance with a second aspect of the present invention, there is provided in a camera system comprising: an image sensor device for sensing an image; a processing means for processing the sensed image; a print media supply means for the supply of print media to a print head; a print head for printing the sensed image on the print media stored internally to the camera system; a portable power supply interconnected to the print head, the sensor and the processing means; and a guillotine mechanism located between the print media supply means and the print head and adapted to cut the print media into sheets of a predetermined size.

[0019] Further, preferably, the guillotine mechanism is detachable from the camera system. The guillotine mechanism can be attached to the print media supply means and is detachable from the camera system with the print media supply means. The guillotine mechanism can be mounted on a platen unit below the print head.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Notwithstanding any other forms which may fall within the scope of the present invention, preferred forms of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

[0021] FIG. 1 illustrates a front perspective view of the assembled camera of the preferred embodiment;

[0022] FIG. 2 illustrates a rear perspective view, partly exploded, of the preferred embodiment;

[0023] FIG. 3 is a perspective view of the chassis of the preferred embodiment;

[0024] FIG. 4 is a perspective view of the chassis illustrating mounting of electric motors;

[0025] FIG. 5 is an exploded perspective of the ink supply mechanism of the preferred embodiment;

[0026] FIG. 6 is rear perspective of the assembled form of the ink supply mechanism of the preferred embodiment;

[0027] FIG. 7 is a front perspective view of the assembled form of the ink supply mechanism of the preferred embodiment;

[0028] FIG. 8 is an exploded perspective view of the platen unit of the preferred embodiment;

[0029] FIG. 9 is a perspective view of the assembled form of the platen unit;

[0030] FIG. 10 is also a perspective view of the assembled form of the platen unit;

[0031] FIG. 11 is an exploded perspective view of the printhead recapping mechanism of the preferred embodiment;

[0032] FIG. 12 is a close up exploded perspective of the recapping mechanism of the preferred embodiment;

[0033] FIG. 13 is an exploded perspective of the ink supply cartridge of the preferred embodiment;

[0034] FIG. 14 is a close up perspective, view partly in section, of the internal portions of the ink supply cartridge in an assembled form;

[0035] FIG. 15 is a schematic block diagram of one form of integrated circuit layer of the image capture and processing integrated circuit of the preferred embodiment;

[0036] FIG. 16 is an exploded view perspective illustrating the assembly process of the preferred embodiment;

[0037] FIG. 17 illustrates a front exploded perspective view of the assembly process of the preferred embodiment;

[0038] FIG. 18 illustrates a perspective view of the assembly process of the preferred embodiment;

[0039] FIG. 19 illustrates a perspective view of the assembly process of the preferred embodiment;

[0040] FIG. 20 is a perspective view illustrating the insertion of the platen unit in the preferred embodiment;

[0041] FIG. 21 illustrates the interconnection of the electrical components of the preferred embodiment;

[0042] FIG. 22 illustrates the process of assembling the preferred embodiment; and

[0043] FIG. 23 is a perspective view further illustrating the assembly process of the preferred embodiment.

DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

[0044] Turning initially simultaneously to FIG. 1 and FIG. 2 there are illustrated perspective views of an assembled camera constructed in accordance with the preferred embodiment with FIG. 1 showing a front perspective view and FIG. 2 showing a rear perspective view. The camera 1 includes a paper or plastic film jacket 2 which can include simplified instructions 3 for the operation of the camera system 1. The camera system 1 includes a first “take” button 4 which is depressed to capture an image. The captured image is output via output slot 6. A further copy of the image can be obtained through depressing a second “printer copy” button 7 whilst an LED light 5 is illuminated. The camera system also provides the usual view finder 8 in addition to a CCD image capture/lensing system 9.

[0045] The camera system 1 provides for a standard number of output prints after which the camera system 1 ceases to function. A prints left indicator slot 10 is provided to indicate the number of remaining prints. A refund scheme at the point of purchase is assumed to be operational for the return of used camera systems for recycling.

[0046] Turning now to FIG. 3, the assembly of the camera system is based around an internal chassis 12 which can be a plastic injection molded part. A pair of paper pinch rollers 28, 29 utilized for decurling are snap fitted into corresponding frame holes eg. 26, 27.

[0047] As shown in FIG. 4, the chassis 12 includes a series of mutually opposed prongs eg. 13, 14 into which is snapped fitted a series of electric motors 16, 17. The electric motors 16, 17 can be entirely standard with the motor 16 being of a stepper motor type. The motor 16, 17 include cogs 19, 20 for driving a series of gear wheels. A first set of gear wheels is provided for controlling a paper cutter mechanism and a second set is provided for controlling print roll movement.

[0048] Turning next to FIGS. 5 to 7, there is illustrated an ink supply mechanism 40 utilized in the camera system. FIG. 5 illustrates a back exploded perspective view, FIG. 6 illustrates a back assembled view and FIG. 7 illustrates a front assembled view. The ink supply mechanism 40 is based around an ink supply cartridge 42 which contains printer ink and a print head mechanism for printing out pictures on demand. The ink supply cartridge 42 includes a side aluminium strip 43 which is provided as a shear strip to assist in cutting images from a paper roll.

[0049] A dial mechanism 44 is provided for indicating the number of “prints left”. The dial mechanism 44 is snap fitted through a corresponding mating portion 46 so as to be freely rotatable.

[0050] As shown in FIG. 6, the mechanism 40 includes a flexible PCB strip 47 which interconnects with the print head and provides for control of the print head. The interconnection between the Flex PCB strip and an image sensor and print head integrated circuit can be via Tape Automated Bonding (TAB) Strips 51, 58. A moulded aspherical lens and aperture shim 50 (FIG. 5) is also provided for imaging an image onto the surface of the image sensor integrated circuit normally located within cavity 53 and a light box module or hood 52 is provided for snap fitting over the cavity 53 so as to provide for proper light control. A series of decoupling capacitors eg. 34 can also be provided. Further a plug 45 (FIG. 7) is provided for re-plugging ink holes after refilling. A series of guide prongs eg. 55-57 are further provided for guiding the flexible PCB strip 47.

[0051] The ink supply mechanism 40 interacts with a platen unit 60 which guides print media under a printhead located in the ink supply mechanism. FIG. 8 shows an exploded view of the platen unit 60, while FIGS. 9 and 10 show assembled views of the platen unit. The platen unit 60 includes a first pinch roller 61 which is snap fitted to one side of a platen base 62. Attached to a second side of the platen base 62 is a cutting mechanism 63 which traverses the platen unit 60 by means of a rod 64 having a screw thread which is rotated by means of cogged wheel 65 which is also fitted to the platen base 62. The screw threaded rod 64 mounts a block 67 which includes a cutting wheel 68 fastened via a fastener 69. Also mounted to the block 67 is a counter actuator which includes a pawl 71. The pawl 71 acts to rotate the dial mechanism 44 of FIG. 6 upon the return traversal of the cutting wheel. As shown previously in FIG. 6, the dial mechanism 44 includes a cogged surface which interacts with pawl 71, thereby maintaining a count of the number of photographs by means of numbers embossed on the surface of dial mechanism 44. The cutting mechanism 63 is inserted into the platen base 62 by means of a snap fit via clips 74.

[0052] The platen unit 60 includes an internal recapping mechanism 80 for recapping the print head when not in use. The recapping mechanism 80 includes a sponge portion 81 and is operated via a solenoid coil so as to provide for recapping of the print head. In the preferred embodiment, there is provided an inexpensive form of printhead re-capping mechanism provided for incorporation into a handheld camera system so as to provide for printhead re-capping of an inkjet printhead.

[0053] FIG. 11 illustrates an exploded view of the recapping mechanism whilst FIG. 12 illustrates a close up of the end portion thereof. The re-capping mechanism 80 is structured around a solenoid including a 16 turn coil 75 which can comprise insulated wire. The coil 75 is turned around a first stationery solenoid arm 76 which is mounted on a bottom surface of the platen base 62 (FIG. 8) and includes a post portion 77 to magnify effectiveness of operation. The arm 76 can comprise a ferrous material.

[0054] A second moveable arm 78 of the solenoid actuator is also provided. The arm 78 is moveable and is also made of ferrous material. Mounted on the arm is a sponge portion surrounded by an elastomer strip 79. The elastomer strip 79 is of a generally arcuate cross-section and act as a leaf spring against the surface of the printhead ink supply cartridge 42 (FIG. 5) so as to provide for a seal against the surface of the printhead ink supply cartridge 42. In the quiescent position an elastomer spring unit 87, 88 acts to resiliently deform the elastomer seal 79 against the surface of the ink supply unit 42.

[0055] When it is desired to operate the printhead unit, upon the insertion of paper, the solenoid coil 75 is activated so as to cause the arm 78 to move down to be adjacent to the end plate 76. The arm 78 is held against end plate 76 while the printhead is printing by means of a small “keeper current” in coil 75. Simulation results indicate that the keeper current can be significantly less than the actuation current. Subsequently, after photo printing, the paper is guillotined by the cutting mechanism 63 of FIG. 8 acting against Aluminium Strip 43, and rewound so as to clear the area of the re-capping mechanism 80. Subsequently, the current is turned off and springs 87, 88 return the arm 78 so that the elastomer seal is again resting against the printhead ink supply cartridge.

[0056] It can be seen that the preferred embodiment provides for a simple and inexpensive means of re-capping a printhead through the utilisation of a solenoid type device having a long rectangular form. Further, the preferred embodiment utilises minimal power in that currents are only required whilst the device is operational and additionally, only a low keeper current is required whilst the printhead is printing.

[0057] Turning next to FIGS. 13 and 14, FIG. 13 illustrates an exploded perspective of the ink supply cartridge 42 whilst FIG. 14 illustrates a close up sectional view of a bottom of the ink supply cartridge with the printhead unit in place. The ink supply cartridge 42 is based around a pagewidth printhead 102 which comprises a long slither of silicon having a series of holes etched on the back surface for the supply of ink to a front surface of the silicon wafer for subsequent ejection via a micro electro mechanical system. The form of ejection can be many different forms such as those set out in the tables below.

[0058] Of course, many other inkjet technologies, as referred to the attached tables below, can also be utilised when constructing a printhead unit 102. The fundamental requirement of the ink supply cartridge 42 is the supply of ink to a series of colour channels etched through the back surface of the printhead 102. In the description of the preferred embodiment, it is assumed that a three colour printing process is to be utilised so as to provide full colour picture output. Hence, the print supply unit includes three ink supply reservoirs being a cyan reservoir 104, a magenta reservoir 105 and a yellow reservoir 106. Each of these reservoirs is required to store ink and includes a corresponding sponge type material 107-109 which assists in stabilising ink within the corresponding ink channel and inhibiting the ink from sloshing back and forth when the printhead is utilised in a handheld camera system. The reservoirs 104, 105, 106 are formed through the mating of first exterior plastic piece 110 and a second base piece 111.

[0059] At a first end 118 of the base piece 111 a series of air inlet 113-115 are provided. Each air inlet leads to a corresponding winding channel which is hydrophobically treated so as to act as an ink repellent and therefore repel any ink that may flow along the air inlet channel. The air inlet channel further takes a convoluted path assisting in resisting any ink flow out of the chambers 104-106. An adhesive tape portion 117 is provided for sealing the channels within end portion 118.

[0060] At the top end, there is included a series of refill holes (not shown) for refilling corresponding ink supply chambers 104, 105, 106. A plug 121 is provided for sealing the refill holes.

[0061] Turning now to FIG. 14, there is illustrated a close up perspective view, partly in section through the ink supply cartridge 42 of FIG. 13 when formed as a unit. The ink supply cartridge includes the three colour ink reservoirs 104, 105, 106 which supply ink to different portions of the back surface of printhead 102 which includes a series of apertures 128 defined therein for carriage of the ink to the front surface.

[0062] The ink supply cartridge 42 includes two guide walls 124, 125 which separate the various ink chambers and are tapered into an end portion abutting the surface of the printhead 102. The guide walls 124, 125 are further mechanically supported by block portions eg. 126 which are placed at regular intervals along the length of the ink supply unit. The block portions 126 leave space at portions close to the back of printhead 102 for the flow of ink around the back surface thereof.

[0063] The ink supply unit is preferably formed from a multi-part plastic injection mould and the mould pieces eg. 110, 111 (FIG. 13) snap together around the sponge pieces 107, 109. Subsequently, a syringe type device can be inserted in the ink refill holes and the ink reservoirs filled with ink with the air flowing out of the air outlets 113-115. Subsequently, the adhesive tape portion 117 and plug 121 are attached and the printhead tested for operation capabilities. Subsequently, the ink supply cartridge 42 can be readily removed for refilling by means of removing the ink supply cartridge, performing a washing cycle, and then utilising the holes for the insertion of a refill syringe filled with ink for refilling the ink chamber before returning the ink supply cartridge 42 to a camera.

[0064] Turning now to FIG. 15, there is shown an example layout of the Image Capture and Processing integrated circuit (ICP) 48.

[0065] The Image Capture and Processing integrated circuit 48 provides most

[0066] of the electronic functionality of the camera with the exception of the print head integrated circuit. The integrated circuit 48 is a highly integrated system. It combines CMOS image sensing, analog to digital conversion, digital image processing, DRAM storage, ROM, and miscellaneous control functions in a single integrated circuit.

[0067] The integrated circuit is estimated to be around 32 mm2 using a

[0068] leading edge 0.18 micron CMOS/DRAM/APS process. The integrated circuit size and cost can scale somewhat with Moore's law, but is dominated by a CMOS active pixel sensor array 201, so scaling is limited as the sensor pixels approach the diffraction limit.

[0069] The ICP 48 includes CMOS logic, a CMOS image sensor, DRAM, and analog circuitry. A very small amount of flash memory or other non-volatile memory is also preferably included for protection against reverse engineering.

[0070] Alternatively, the ICP can readily be divided into two integrated circuits: one for the CMOS imaging array, and the other for the remaining circuitry. The cost of this two integrated circuit solution should not be significantly different than the single integrated circuit ICP, as the extra cost of packaging and bond-pad area is somewhat cancelled by the reduced total wafer area requiring the color filter fabrication steps.

[0071] The ICP preferably contains the following functions: 1

Function
1.5 megapixel image sensor
Analog Signal Processors
Image sensor column decoders
Image sensor row decoders
Analogue to Digital Conversion (ADC)
Column ADC's
Auto exposure
12 Mbits of DRAM
DRAM Address Generator
Color interpolator
Convolver
Color ALU
Halftone matrix ROM
Digital halftoning
Print head interface
8 bit CPU core
Program ROM
Flash memory
Scratchpad SRAM
Parallel interface (8 bit)
Motor drive transistors (5)
Clock PLL
JTAG test interface
Test circuits
Busses
Bond pads

[0072] The CPU, DRAM, Image sensor, ROM, Flash memory, Parallel interface, JTAG interface and ADC can be vendor supplied cores. The ICP is intended to run on 1.5V to minimize power consumption and allow convenient operation from two AA type battery cells.

[0073] FIG. 15 illustrates a layout of the ICP 48. The ICP 48 is dominated by the imaging array 201, which consumes around 80% of the integrated circuit area. The imaging array is a CMOS 4 transistor active pixel design with a resolution of 1,500×1,000. The array can be divided into the conventional configuration, with two green pixels, one red pixel, and one blue pixel in each pixel group. There are 750×500 pixel groups in the imaging array.

[0074] The latest advances in the field of image sensing and CMOS image sensing in particular can be found in the October, 1997 issue of IEEE Transactions on Electron Devices and, in particular, pages 1689 to 1968. Further, a specific implementation similar to that disclosed in the present application is disclosed in Wong et. al, “CMOS Active Pixel Image Sensors Fabricated Using a 1.8V, 0.25 μm CMOS Technology”, IEDM 1996, page 915

[0075] The imaging array uses a 4 transistor active pixel design of a standard configuration. To minimize integrated circuit area and therefore cost, the image sensor pixels should be as small as feasible with the technology available. With a four transistor cell, the typical pixel size scales as 20 times the lithographic feature size. This allows a minimum pixel area of around 3.6 μm×3.6 μm. However, the photosite must be substantially above the diffraction limit of the lens. It is also advantageous to have a square photosite, to maximize the margin over the diffraction limit in both horizontal and vertical directions. In this case, the photosite can be specified as 2.5 μm×2.5 μm. The photosite can be a photogate, pinned photodiode, charge modulation device, or other sensor.

[0076] The four transistors are packed as an ‘L’ shape, rather than a rectangular region, to allow both the pixel and the photosite to be square. This reduces the transistor packing density slightly, increasing pixel size. However, the advantage in avoiding the diffraction limit is greater than the small decrease in packing density.

[0077] The transistors also have a gate length which is longer than the minimum for the process technology. These have been increased from a drawn length of 0.18 micron to a drawn length of 0.36 micron. This is to improve the transistor matching by making the variations in gate length represent a smaller proportion of the total gate length.

[0078] The extra gate length, and the ‘L’ shaped packing, mean that the transistors use more area than the minimum for the technology. Normally, around 8 μm2 would be required for rectangular packing. Preferably, 9.75 μm2 has been allowed for the transistors.

[0079] The total area for each pixel is 16 μm2, resulting from a pixel size of 4 μm×4 μm. With a resolution of 1,500×1,000, the area of the imaging array 101 is 6,000 μm×4,000 μm, or 24 mm2.

[0080] The presence of a color image sensor on the integrated circuit affects the process required in two major ways:

[0081] The CMOS fabrication process should be optimized to minimize dark current

[0082] Color filters are required. These can be fabricated using dyed photosensitive polyimides, resulting in an added process complexity of three spin coatings, three photolithographic steps, three development steps, and three hardbakes.

[0083] There are 15,000 analog signal processors (ASPs) 205, one for each of the columns of the sensor. The ASPs amplify the signal, provide a dark current reference, sample and hold the signal, and suppress the fixed pattern noise (FPN).

[0084] There are 375 analog to digital converters 206, one for each four columns of the sensor array. These may be delta-sigma or successive approximation type ADC's. A row of low column ADC's are used to reduce the conversion speed required, and the amount of analog signal degradation incurred before the signal is converted to digital. This also eliminates the hot spot (affecting local dark current) and the substrate coupled noise that would occur if a single high speed ADC was used. Each ADC also has two four bit DAC's which trim the offset and scale of the ADC to further reduce FPN variations between columns. These DAC's are controlled by data stored in flash memory during integrated circuit testing.

[0085] The column select logic 204 is a 1:1500 decoder which enables the appropriate digital output of the ADCs onto the output bus. As each ADC is shared by four columns, the least significant two bits of the row select control 4 input analog multiplexors.

[0086] A row decoder 207 is a 1:1000 decoder which enables the appropriate row of the active pixel sensor array. This selects which of the 1000 rows of the imaging array is connected to analog signal processors. As the rows are always accessed in sequence, the row select logic can be implemented as a shift register.

[0087] An auto exposure system 208 adjusts the reference voltage of the ADC 205 in response to the maximum intensity sensed during the previous frame period. Data from the green pixels is passed through a digital peak detector. The peak value of the image frame period before capture (the reference frame) is provided to a digital to analogue converter (DAC), which generates the global reference voltage for the column ADCs. The peak detector is reset at the beginning of the reference frame. The minimum and maximum values of the three RGB color components are also collected for color correction.

[0088] The second largest section of the integrated circuit is consumed by a DRAM 210 used to hold the image. To store the 1,500×1,000 image from the sensor without compression, 1.5 Mbytes of DRAM 210 are required. This equals 12 Mbits, or slightly less than 5% of a 256 Mbit DRAM. The DRAM technology assumed is of the 256 Mbit generation implemented using 0.18 μm CMOS.

[0089] Using a standard 8F cell, the area taken by the memory array is 3.11 mm2. When row decoders, column sensors, redundancy, and other factors are taken into account, the DRAM requires around 4 mm2.

[0090] This DRAM 210 can be mostly eliminated if analog storage of the image signal can be accurately maintained in the CMOS imaging array for the two seconds required to print the photo. However, digital storage of the image is preferable as it is maintained without degradation, is insensitive to noise, and allows copies of the photo to be printed considerably later.

[0091] A DRAM address generator 211 provides the write and read addresses to the DRAM 210. Under normal operation, the write address is determined by the order of the data read from the CMOS image sensor 201. This will typically be a simple raster format. However, the data can be read from the sensor 201 in any order, if matching write addresses to the DRAM are generated. The read order from the DRAM 210 will normally simply match the requirements of a color interpolator and the print head. As the cyan, magenta, and yellow rows of the print head are necessarily offset by a few pixels to allow space for nozzle actuators, the colors are not read from the DRAM simultaneously. However, there is plenty of time to read all of the data from the DRAM many times during the printing process. This capability is used to eliminate the need for FIFOs in the print head interface, thereby saving integrated circuit area. All three RGB image components can be read from the DRAM each time color data is required. This allows a color space converter to provide a more sophisticated conversion than a simple linear RGB to CMY conversion.

[0092] Also, to allow two dimensional filtering of the image data without requiring line buffers, data is re-read from the DRAM array.

[0093] The address generator may also implement image effects in certain models of camera. For example, passport photos are generated by a manipulation of the read addresses to the DRAM. Also, image framing effects (where the central image is reduced), image warps, and kaleidoscopic effects can all be generated by manipulating the read addresses of the DRAM.

[0094] While the address generator 211 may be implemented with substantial complexity if effects are built into the standard integrated circuit, the integrated circuit area required for the address generator is small, as it consists only of address counters and a moderate amount of random logic.

[0095] A color interpolator 214 converts the interleaved pattern of red, 2× green, and blue pixels into RGB pixels. It consists of three 8 bit adders and associated registers. The divisions are by either 2 (for green) or 4 (for red and blue) so they can be implemented as fixed shifts in the output connections of the adders.

[0096] A convolver 215 is provided as a sharpening filter which applies a small convolution kernel (5×5) to the red, green, and blue planes of the image. The convolution kernel for the green plane is different from that of the red and blue planes, as green has twice as many samples. The sharpening filter has five functions:

[0097] To improve the color interpolation from the linear interpolation provided by the color interpolator, to a close approximation of a sinc interpolation.

[0098] To compensate for the image ‘softening’ which occurs during digitization.

[0099] To adjust the image sharpness to match average consumer preferences, which are typically for the image to be slightly sharper than reality. As the single use camera is intended as a consumer product, and not a professional photographic products, the processing can match the most popular settings, rather than the most accurate.

[0100] To suppress the sharpening of high frequency (individual pixel) noise. The function is similar to the ‘unsharp mask’ process.

[0101] To antialias Image Warping.

[0102] These functions are all combined into a single convolution matrix. As the pixel rate is low (less than 1 Mpixel per second) the total number of multiplies required for the three color channels is 56 million multiplies per second. This can be provided by a single multiplier. Fifty bytes of coefficient ROM are also required.

[0103] A color ALU 113 combines the functions of color compensation and color space conversion into the one matrix multiplication, which is applied to every pixel of the frame. As with sharpening, the color correction should match the most popular settings, rather than the most accurate.

[0104] A color compensation circuit of the color ALU provides compensation for the lighting of the photo. The vast majority of photographs are substantially improved by a simple color compensation, which independently normalizes the contrast and brightness of the three color components.

[0105] A color look-up table (CLUT) 212 is provided for each color component. These are three separate 256×8 SRAMs, requiring a total of 6,144 bits. The CLUTs are used as part of the color correction process. They are also used for color special effects, such as stochastically selected “wild color” effects.

[0106] A color space conversion system of the color ALU converts from the RGB color space of the image sensor to the CMY color space of the printer. The simplest conversion is a 1's complement of the RGB data. However, this simple conversion assumes perfect linearity of both color spaces, and perfect dye spectra for both the color filters of the image sensor, and the ink dyes. At the other extreme is a tri-linear interpolation of a sampled three dimensional arbitrary transform table. This can effectively match any non-linearity or differences in either color space. Such a system is usually necessary to obtain good color space conversion when the print engine is a color electrophotographic

[0107] However, since the non-linearity of a halftoned ink jet output is very small, a simpler system can be used. A simple matrix multiply can provide excellent results. This requires nine multiplies and six additions per contone pixel. However, since the contone pixel rate is low (less than 1 Mpixel/sec) these operations can share a single multiplier and adder. The multiplier and adder are used in a color ALU which is shared with the color compensation function.

[0108] Digital halftoning can be performed as a dispersed dot ordered dither using a stochastic optimized dither cell. A halftone matrix ROM 216 is provided for storing dither cell coefficients. A dither cell size of 32×32 is adequate to ensure that the cell repeat cycle is not visible. The three colors—cyan, magenta, and yellow—are all dithered using the same cell, to ensure maximum co-positioning of the ink dots. This minimizes ‘muddying’ of the mid-tones which results from bleed of dyes from one dot to adjacent dots while still wet. The total ROM size required is 1 KByte, as the one ROM is shared by the halftoning units for each of the three colors.

[0109] The digital halftoning used is dispersed dot ordered dither with stochastic optimized dither matrix. While dithering does not produce an image quite as ‘sharp’ as error diffusion, it does produce a more accurate image with fewer artifacts. The image sharpening produced by error diffusion is artificial, and less controllable and accurate than ‘unsharp mask’ filtering performed in the contone domain. The high print resolution (1,600 dpi×1,600 dpi) results in excellent quality when using a well formed stochastic dither matrix.

[0110] Digital halftoning is performed by a digital halftoning unit 217 using a simple comparison between the contone information from the DRAM 210 and the contents of the dither matrix 216. During the halftone process, the resolution of the image is changed from the 250 dpi of the captured contone image to the 1,600 dpi of the printed image. Each contone pixel is converted to an average of 40.96 halftone dots.

[0111] The ICP incorporates a 16 bit microcontroller CPU core 219 to run the miscellaneous camera functions, such as reading the buttons, controlling the motor and solenoids, setting up the hardware, and authenticating the refill station. The processing power required by the CPU is very modest, and a wide variety of processor cores can be used. As the entire CPU program is run from a small ROM 220[.], program compatibility between camera versions is not important, as no external programs are run. A 2 Mbit (256 Kbyte) program and data ROM 220 is included on integrated circuit. Most of this ROM space is allocated to data for outline graphics and fonts for specialty cameras. The program requirements are minor. The single most complex task is the encrypted authentication of the refill station. The ROM requires a single transistor per bit.

[0112] A Flash memory 221 may be used to store a 128 bit authentication code. This provides higher security than storage of the authentication code in ROM, as reverse engineering can be made essentially impossible. The Flash memory is completely covered by third level metal, making the data impossible to extract using scanning probe microscopes or electron beams. The authentication code is stored in the integrated circuit when manufactured. At least two other Flash bits are required for the authentication process: a bit which locks out reprogramming of the authentication code, and a bit which indicates that the camera has been refilled by an authenticated refill station. The flash memory can also be used to store FPN correction data for the imaging array. Additionally, a phase locked loop resealing parameter is stored for scaling the clocking cycle to an appropriate correct time. The clock frequency does not require crystal accuracy since no date functions are provided. To eliminate the cost of a crystal, an on integrated circuit oscillator with a phase locked loop 224 is used. As the frequency of an on-integrated circuit oscillator is highly variable from integrated circuit to integrated circuit, the frequency ratio of the oscillator to the PLL is digitally trimmed during initial testing. The value is stored in Flash memory 221. This allows the clock PLL to control the ink-jet heater pulse width with sufficient accuracy.

[0113] A scratchpad SRAM is a small static RAM 222 with a 6T cell. The scratchpad provided temporary memory for the 16 bit CPU. 1024 bytes is adequate.

[0114] A print head interface 223 formats the data correctly for the print head. The print head interface also provides all of the timing signals required by the print head. These timing signals may vary depending upon temperature, the number of dots printed simultaneously, the print medium in the print roll, and the dye density of the ink in the print roll.

[0115] The following is a table of external connections to the print head interface: 2

ConnectionFunctionPins
DataBits[0-7]Independent serial data to the eight segments of the print8
head
BitClockMain data clock for the print head1
ColorEnable[0-2]Independent enable signals for the CMY actuators,3
allowing different pulse times for each color.
BankEnable[0-1]Allows either simultaneous or interleaved actuation of two2
banks of nozzles. This allows two different print
speed/power consumption tradeoffs
NozzleSelect[0-4]Selects one of 32 banks of nozzles for simultaneous5
actuation
ParallelXferClockLoads the parallel transfer register with the data from the1
shift registers
Total20 

[0116] The print head utilized is composed of eight identical segments, each 1.25 cm long. There is no connection between the segments on the print head integrated circuit. Any connections required are made in the external TAB bonding film, which is double sided. The division into eight identical segments is to simplify lithography using wafer steppers. The segment width of 1.25 cm fits easily into a stepper field. As the print head integrated circuit is long and narrow (10 cm×0.3 mm), the stepper field contains a single segment of 32 print head integrated circuits. The stepper field is therefore 1.25 cm×1.6 cm. An average of four complete print heads are patterned in each wafer step.

[0117] A single BitClock output line connects to all 8 segments on the print head. The 8 DataBits lines lead one to each segment, and are clocked into the 8 segments on the print head simultaneously (on a BitClock pulse). For example, dot 0 is transferred to segment0, dot 750 is transferred to segment1, dot 1500 to segment2 etc simultaneously.

[0118] The ParallelXferClock is connected to each of the 8 segments on the print head, so that on a single pulse, all segments transfer their bits at the same time.

[0119] The NozzleSelect, BankEnable and ColorEnable lines are connected to each of the 8 segments, allowing the print head interface to independently control the duration of the cyan, magenta, and yellow nozzle energizing pulses. Registers in the Print Head Interface allow the accurate specification of the pulse duration between 0 and 6 ms, with a typical duration of 2 ms to 3 ms.

[0120] A parallel interface 125 connects the ICP to individual static electrical signals. The CPU is able to control each of these connections as memory mapped I/O via a low speed bus.

[0121] The following is a table of connections to the parallel interface: 3

ConnectionDirectionPins
Paper transport stepper motorOutput4
Capping solenoidOutput1
Copy LEDOutput1
Photo buttonInput1
Copy buttonInput1
Total8

[0122] Seven high current drive transistors eg. 227 are required. Four are for the four phases of the main stepper motors two are for the guillotine motor, and the remaining transistor is to drive the capping solenoid. These transistors are allocated 20,000 square microns (600,000 F) each. As the transistors are driving highly inductive loads, they must either be turned off slowly, or be provided with a high level of back EMF protection. If adequate back EMF protection cannot be provided using the integrated circuit process chosen, then external discrete transistors should be used. The transistors are never driven at the same time as the image sensor is used. This is to avoid voltage fluctuations and hot spots affecting the image quality. Further, the transistors are located as far away from the sensor as possible.

[0123] A standard JTAG (Joint Test Action Group) interface 228 is included in the ICP for testing purposes and for interrogation by the refill station. Due to the complexity of the integrated circuit, a variety of testing techniques are required, including BIST (Built In Self Test) and functional block isolation. An overhead of 10% in integrated circuit area is assumed for integrated circuit testing circuitry for the random logic portions. The overhead for the large arrays the image sensor and the DRAM is smaller.

[0124] The JTAG interface is also used for authentication of the refill station. This is included to ensure that the cameras are only refilled with quality paper and ink at a properly constructed refill station, thus preventing inferior quality refills from occurring. The camera must authenticate the refill station, rather than vice versa. The secure protocol is communicated to the refill station during the automated test procedure. Contact is made to four gold plated spots on the ICP/print head TAB by the refill station as the new ink is injected into the print head.

[0125] FIG. 16 illustrates a rear view of the next step in the construction process whilst FIG. 17 illustrates a front view.

[0126] Turning now to FIG. 16, the assembly of the camera system proceeds via first assembling the ink supply mechanism 40. The flex PCB is interconnected with batteries 84 only one of which is shown, which are inserted in the middle portion of a print roll 85 which is wrapped around a plastic former 86. An end cap 89 is provided at the other end of the print roll 85 so as to fasten the print roll and batteries firmly to the ink supply mechanism.

[0127] The solenoid coil is interconnected (not shown) to interconnects 97, 98 (FIG. 8) which include leaf spring ends for interconnection with electrical contacts on the Flex PCB so as to provide for electrical control of the solenoid.

[0128] Turning now to FIGS. 17-19 the next step in the construction process is the insertion of the relevant gear trains into the side of the camera chassis. FIG. 17 illustrates a front view, FIG. 18 illustrates a rear view and FIG. 19 also illustrates a rear view. The first gear train comprising gear wheels 22, 23 is utilised for driving the guillotine blade with the gear wheel 23 engaging the gear wheel 65 of FIG. 8. The second gear train comprising gear wheels 24, 25 and 26 engage one end of the print roller 61 of FIG. 8. As best indicated in FIG. 18, the gear wheels mate with corresponding pins on the surface of the chassis with the gear wheel 26 being snap fitted into corresponding mating hole 27.

[0129] Next, as illustrated in FIG. 20, the assembled platen unit 60 is then inserted between the print roll 85 and aluminium cutting blade 43.

[0130] Turning now to FIG. 21, by way of illumination, there is illustrated the electrically interactive components of the camera system. As noted previously, the components are based around a Flex PCB board and include a TAB film 58 which interconnects the printhead 102 with the image sensor and processing integrated circuit 48. Power is supplied by two AA type batteries 83, 84 and a paper drive stepper motor 16 is provided in addition to a rotary guillotine motor 17.

[0131] An optical element 31 is provided for snapping into a top portion of the chassis 12. The optical element 31 includes portions defining an optical view finder 32, 33 which are slotted into mating portions 35, 36 in view finder channel 37. Also provided in the optical element 31 is a lensing system 38 for magnification of the prints left number in addition to an optical pipe element 39 for piping light from the LED 5 for external display.

[0132] Turning next to FIG. 22, the assembled unit 90 is then inserted into a front outer case 91 which includes button 4 for activation of printouts.

[0133] Turning now to FIG. 23, next, the unit 90 is provided with a snap-on back cover 93 which includes a slot 6 and copy print button 7. A wrapper label containing instructions and advertising (not shown) is then wrapped around the outer surface of the camera system and pinch clamped to the cover by means of clamp strip 96 which can comprise a flexible plastic or rubber strip.

[0134] Subsequently, the preferred embodiment is ready for use as a one time use camera system that provides for instant output images on demand. It will be evident that the preferred embodiment further provides for a refillable camera system. A used camera can be collected and its outer plastic cases removed and recycled. A new paper roll and batteries can be added and the ink cartridge refilled. A series of automatic test routines can then be carried out to ensure that the printer is properly operational. Further, in order to ensure only authorised refills are conducted so as to enhance quality, routines in the on-integrated circuit program ROM can be executed such that the camera authenticates the refilling station using a secure protocol. Upon authentication, the camera can reset an internal paper count and an external case can be fitted on the camera system with a new outer label. Subsequent packing and shipping can then take place.

[0135] It will be further readily evident to those skilled in the art that the program ROM can be modified so as to allow for a variety of digital processing routines. In addition to the digitally enhanced photographs optimised for mainstream consumer preferences, various other models can readily be provided through mere re-programming of the program ROM. For example, a sepia classic old fashion style output can be provided through a remapping of the colour mapping function. A further alternative is to provide for black and white outputs again through a suitable colour remapping algorithm. Minimum colour can also be provided to add a touch of colour to black and white prints to produce the effect that was traditionally used to colourize black and white photos. Further, passport photo output can be provided through suitable address remappings within the address generators. Further, edge filters can be utilised as is known in the field of image processing to produce sketched art styles. Further, classic wedding borders and designs can be placed around an output image in addition to the provision of relevant clip arts. For example, a wedding style camera might be provided. Further, a panoramic mode can be provided so as to output the well known panoramic format of images. Further, a postcard style output can be provided through the printing of postcards including postage on the back of a print roll surface. Further, cliparts can be provided for special events such as Halloween, Christmas etc. Further, kaleidoscopic effects can be provided through address remappings and wild colour effects can be provided through remapping of the colour lookup table. Many other forms of special event cameras can be provided for example, cameras dedicated to the Olympics, movie tie-ins, advertising and other special events.

[0136] The operational mode of the camera can be programmed so that upon the depressing of the take photo a first image is sampled by the sensor array to determine irrelevant parameters. Next a second image is again captured which is utilised for the output. The captured image is then manipulated in accordance with any special requirements before being initially output on the paper roll. The LED light is then activated for a predetermined time during which the DRAM is refreshed so as to retain the image. If the print copy button is depressed during this predetermined time interval, a further copy of the photo is output. After the predetermined time interval where no use of the camera has occurred, the onboard CPU shuts down all power to the camera system until such time as the take button is again activated. In this way, substantial power savings can be realized.

[0137] Ink Jet Technologies

[0138] The embodiments of the invention use an ink jet printer type device. Of course many different devices could be used. However presently popular ink jet printing technologies are unlikely to be suitable.

[0139] The most significant problem with thermal inkjet is power consumption. This is approximately 100 times that required for high speed, and stems from the energy-inefficient means of drop ejection. This involves the rapid boiling of water to produce a vapor bubble which expels the ink. Water has a very high heat capacity, and must be superheated in thermal inkjet applications. This leads to an efficiency of around 0.02%, from electricity input to drop momentum (and increased surface area) out.

[0140] The most significant problem with piezoelectric inkjet is size and cost. Piezoelectric crystals have a very small deflection at reasonable drive voltages, and therefore require a large area for each nozzle. Also, each piezoelectric actuator must be connected to its drive circuit on a separate substrate. This is not a significant problem at the current limit of around 300 nozzles per print head, but is a major impediment to the fabrication of pagewide print heads with 19,200 nozzles.

[0141] Ideally, the inkjet technologies used meet the stringent requirements of in-camera digital color printing and other high quality, high speed, low cost printing applications. To meet the requirements of digital photography, new inkjet technologies have been created. The target features include:

[0142] low power (less than 10 Watts)

[0143] high resolution capability (1,600 dpi or more)

[0144] photographic quality output

[0145] low manufacturing cost

[0146] small size (pagewidth times minimum cross section)

[0147] high speed (<2 seconds per page).

[0148] All of these features can be met or exceeded by the inkjet systems described below with differing levels of difficulty. 45 different inkjet technologies have been developed by the Assignee to give a wide range of choices for high volume manufacture. These technologies form part of separate applications assigned to the present Assignee as set out in the table below.

[0149] The inkjet designs shown here are suitable for a wide range of digital printing systems, from battery powered one-time use digital cameras, through to desktop and network printers, and through to commercial printing systems

[0150] For ease of manufacture using standard process equipment, the print head is designed to be a monolithic 0.5 micron CMOS integrated circuit with MEMS post processing. For color photographic applications, the print head is 100 mm long, with a width which depends upon the inkjet type. The smallest print head designed is IJ38, which is 0.35 mm wide, giving a integrated circuit area of 35 square mm. The print heads each contain 19,200 nozzles plus data and control circuitry.

[0151] Ink is supplied to the back of the print head by injection molded plastic ink channels. The molding requires 50 micron features, which can be created using a lithographically micromachined insert in a standard injection molding tool. Ink flows through holes etched through the wafer to the nozzle chambers fabricated on the front surface of the wafer. The print head is connected to the camera circuitry by tape automated bonding.

[0152] Cross-Referenced Applications

[0153] The following table is a guide to cross-referenced patent applications filed concurrently herewith and discussed hereinafter with the reference being utilized in subsequent tables when referring to a particular case: 4

Docket
No.ReferenceTitle
IJ01USIJ01Radiant Plunger Ink Jet Printer
IJ02USIJ02Electrostatic Ink Jet Printer
IJ03USIJ03Planar Thermoelastic Bend Actuator Ink Jet
IJ04USIJ04Stacked Electrostatic Ink Jet Printer
IJ05USIJ05Reverse Spring Lever Ink Jet Printer
IJ06USIJ06Paddle Type Ink Jet Printer
IJ07USIJ07Permanent Magnet Electromagnetic Ink Jet Printer
IJ08USIJ08Planar Swing Grill Electromagnetic Ink Jet Printer
IJ09USIJ09Pump Action Refill Ink Jet Printer
IJ10USIJ10Pulsed Magnetic Field Ink Jet Printer
IJ11USIJ11Two Plate Reverse Firing Electromagnetic Ink Jet Printer
IJ12USIJ12Linear Stepper Actuator Ink Jet Printer
IJ13USIJ13Gear Driven Shutter Ink Jet Printer
IJ14USIJ14Tapered Magnetic Pole Electromagnetic Ink Jet Printer
IJ15USIJ15Linear Spring Electromagnetic Grill Ink Jet Printer
IJ16USIJ16Lorenz Diaphragm Electromagnetic Ink Jet Printer
IJ17USIJ17PTFE Surface Shooting Shuttered Oscillating Pressure Ink Jet Printer
IJ18USIJ18Buckle Grip Oscillating Pressure Ink Jet Printer
IJ19USIJ19Shutter Based Ink Jet Printer
IJ20USIJ20Curling Calyx Thermoelastic Ink Jet Printer
IJ21USIJ21Thermal Actuated Ink Jet Printer
IJ22USIJ22Iris Motion Ink Jet Printer
IJ23USIJ23Direct Firing Thermal Bend Actuator Ink Jet Printer
IJ24USIJ24Conductive PTFE Ben Activator Vented Ink Jet Printer
IJ25USIJ25Magnetostrictive Ink Jet Printer
IJ26USIJ26Shape Memory Alloy Ink Jet Printer
IJ27USIJ27Buckle Plate Ink Jet Printer
IJ28USIJ28Thermal Elastic Rotary Impeller Ink Jet Printer
IJ29USIJ29Thermoelastic Bend Actuator Ink Jet Printer
IJ30USIJ30Thermoelastic Bend Actuator Using PTFE and Corrugated Copper
Ink Jet Printer
IJ31USIJ31Bend Actuator Direct Ink Supply Ink Jet Printer
IJ32USIJ32A High Young's Modulus Thermoelastic Ink Jet Printer
IJ33USIJ33Thermally actuated slotted chamber wall ink jet printer
IJ34USIJ34Ink Jet Printer having a thermal actuator comprising an external
coiled spring
IJ35USIJ35Trough Container Ink Jet Printer
IJ36USIJ36Dual Chamber Single Vertical Actuator Ink Jet
IJ37USIJ37Dual Nozzle Single Horizontal Fulcrum Actuator Ink Jet
IJ38USIJ38Dual Nozzle Single Horizontal Actuator Ink Jet
IJ39USIJ39A single bend actuator cupped paddle ink jet printing device
IJ40USIJ40A thermally actuated ink jet printer having a series of thermal
actuator units
IJ41USIJ41A thermally actuated ink jet printer including a tapered heater
element
IJ42USIJ42Radial Back-Curling Thermoelastic Ink Jet
IJ43USIJ43Inverted Radial Back-Curling Thermoelastic Ink Jet
IJ44USIJ44Surface bend actuator vented ink supply ink jet printer
IJ45USIJ45Coil Acutuated Magnetic Plate Ink Jet Printer

[0154] Tables of Drop-on-Demand Inkjets

[0155] Eleven important characteristics of the fundamental operation of individual ink-jet nozzles have been identified. These characteristics are largely orthogonal, and so can be elucidated as an eleven dimensional matrix. Most of the eleven axes of this matrix include entries developed by the present assignee.

[0156] The following tables form the axes of an eleven dimensional table of inkjet types.

[0157] Actuator mechanism (18 types)

[0158] Basic operation mode (7 types)

[0159] Auxiliary mechanism (8 types)

[0160] Actuator amplification or modification method (17 types)

[0161] Actuator motion (19 types)

[0162] Nozzle refill method (4 types)

[0163] Method of restricting back-flow through inlet (10 types)

[0164] Nozzle clearing method (9 types)

[0165] Nozzle plate construction (9 types)

[0166] Drop ejection direction (5 types)

[0167] Ink type (7 types)

[0168] The complete eleven dimensional table represented by these axes contains 36.9 billion possible configurations of inkjet nozzle. While not all of the possible combinations result in a viable inkjet technology, many million configurations are viable. It is clearly impractical to elucidate all of the possible configurations. Instead, certain inkjet types have been investigated in detail. These are designated IJ01 to IJ45 above.

[0169] Other inkjet configurations can readily be derived from these 45 examples by substituting alternative configurations along one or more of the 11 axes. Most of the IJ01 to IJ45 examples can be made into inkjet print heads with characteristics superior to any currently available inkjet technology.

[0170] Where there are prior art examples known to the inventor, one or more of these examples are listed in the examples column of the tables below. The IJ01 to IJ45 series are also listed in the examples column. In some cases, a printer may be listed more than once in a table, where it shares characteristics with more than one entry.

[0171] Suitable applications include: Home printers, Office network printers, Short run digital printers, Commercial print systems, Fabric printers, Pocket printers, Internet WWW printers, Video printers, Medical imaging, Wide format printers, Notebook PC printers, Fax machines, Industrial printing systems, Photocopiers, Photographic minilabs etc.

[0172] The information associated with the aforementioned 11 dimensional matrix are set out in the following tables.

[0173] Actuator Mechanism (Applied Only to Selected Ink Drops) 5

Actu-
ator
Mech-
anismDescriptionAdvantagesDisadvantagesExamples
ThermalAn electrothermal heater heats the1) Large force generated6) High power16) Canon
bubbleink to above boiling point,2) Simple construction7) Ink carrier limited to waterBubblejet 1979 Endo
transferring significant heat to the3) No moving parts8) Low efficiencyet al GB patent
aqueous ink. A bubble nucleates and4) Fast operation9) High temperatures required2,007,162
quickly forms, expelling the ink.5) Small integrated circuit area10) High mechanical stress17) Xerox heater-in-
The efficiency of the process is low,required for actuator11) Unusual materials requiredpit 1990 Hawkins et
with typically less than 0.05% of the12) Large drive transistorsal U.S. Pat. No.
electrical energy being transformed13) Cavitation causes actuator failure4,899,181
into kinetic energy of the drop.14) Kogation reduces bubble18) Hewlett-Packard TIJ
formation1982 Vaught et al
15) Large print heads are difficult toU.S. Pat. No. 4,490,728
fabricate
Piezo-A piezoelectric crystal such as lead19) Low power23) Very large area required for28) Kyser et al
electriclanthanum zirconate (PZT) isconsumptionactuatorU.S. Pat. No. 3,946,398
electrically activated, and either20) Many ink types can be24) Difficult to integrate with29) Zoltan U.S. Pat. No.
expands, shears, or bends to applyusedelectronics3,683,212
pressure to the ink, ejecting drops.21) Fast operation25) High voltage drive transistors30) 1973 Stemme
22) High efficiencyrequiredU.S. Pat. No. 3,747,120
26) Full pagewidth print heads31) Epson Stylus
impractical due to actuator size32) Tektronix
27) Requires electrical poling in high33) IJ04
field strengths during manufacture
Electro-An electric field is used to activate34) Low power39) Low maximum strain (approx.44) Seiko Epson,
strictiveelectrostriction in relaxor materialsconsumption0.01%)Usui et all JP
such as lead lanthanum zirconate35) Many ink types can be40) Large area required for actuator253401/96
titanate (PLZT) or lead magnesiumuseddue to low strain45) IJ04
niobate (PMN).36) Low thermal41) Response speed is marginal (˜10 μs)
expansion42) High voltage drive transistors
37) Electric field strengthrequired
required (approx. 3.5 V/μm)43) Full pagewidth print heads
can be generated withoutimpractical due to actuator size
difficulty
38) Does not require
electrical poling
Ferro-An electric field is used to induce a46) Low power52) Difficult to integrate with55) IJ04
electricphase transition between theconsumptionelectronics
antiferroelectric (AFE) and47) Many ink types can be53) Unusual materials such as
ferroelectric (FE) phase. PerovskiteusedPLZSnT are required
materials such as tin modified lead48) Fast operation (<1 μs)54) Actuators require a large area
lanthanum zirconate titanate49) Relatively high
(PLZSnT) exhibit large strains of uplongitudinal strain
to 1% associated with the AFE to FE50) High efficiency
phase transition.51) Electric field strength
of around 3 V/μm can be
readily provided
Electro-Conductive plates are separated by a56) Low power59) Difficult to operate electrostatic64) IJ02, IJ04
staticcompressible or fluid dielectricconsumptiondevices in an aqueous environment
plates(usually air). Upon application of a57) Many ink types can be60) The electrostatic actuator will
voltage, the plates attract each otherusednormally need to be separated from the
and displace ink, causing drop58) Fast operationink
ejection. The conductive plates may61) Very large area required to
be in a comb or honeycombachieve high forces
structure, or stacked to increase the62) High voltage drive transistors
surface area and therefore the force.may be required
63) Full pagewidth print heads are not
competitive due to actuator size
Electro-A strong electric field is applied to65) Low current67) High voltage required72) 1989 Saito et al,
staticthe ink, whereupon electrostaticconsumption68) May be damaged by sparks due toU.S. Pat. No. 4,799,068
pull onattraction accelerates the ink towards66) Low temperatureair breakdown73) 1989 Miura et
inkthe print medium.69) Required field strength increasesal, U.S. Pat. No.
as the drop size decreases4,810,954
70) High voltage drive transistors74) Tone-jet
required
71) Electrostatic field attracts dust
Perma-An electromagnet directly attracts a75) Low power80) Complex fabrication86) IJ07, IJ10
nentpermanent magnet, displacing inkconsumption81) Permanent magnetic material
magnetand causing drop ejection. Rare earth76) Many ink types can besuch as Neodymium Iron Boron
electro-magnets with a field strength aroundused(NdFeB) required.
mag-1 Tesla can be used. Examples are:77) Fast operation82) High local currents required
neticSamarium Cobalt (SaCo) and78) High efficiency83) Copper metalization should be
magnetic materials in the neodymium79) Easy extension fromused for long electromigration lifetime
iron boron family (NdFeB,single nozzles to pagewidthand low resistivity
NdDyFeBNb, NdDyFeB, etc)print heads84) Pigmented inks are usually
infeasible
85) Operating temperature limited to
the Curie temperature (around 540 K)
SoftA solenoid induced a magnetic field87) Low power92) Complex fabrication98) IJ01, IJ05, IJ08,
mag-in a soft magnetic core or yokeconsumption93) Materials not usually present in aIJ10
neticfabricated from a ferrous material88) Many ink types can beCMOS fab such as NiFe, CoNiFe, or99) IJ12, IJ14, IJ15,
coresuch as electroplated iron alloys suchusedCoFe are requiredIJ17
electro-as CoNiFe [1], CoFe, or NiFe alloys.89) Fast operation94) High local currents required
mag-Typically, the soft magnetic material90) High efficiency95) Copper metalization should be
neticis in two parts, which are normally91) Easy extension fromused for long electromigration lifetime
held apart by a spring. When thesingle nozzles to pagewidthand low resistivity
solenoid is actuated, the two partsprint heads96) Electroplating is required
attract, displacing the ink.97) High saturation flux density is
required (2.0-2.1 T is achievable with
CoNiFe[1])
Mag-The Lorenz force acting on a current100) Low power105) Force acts as a twisting motion110) IJ06, IJ11, IJ13,
neticcarrying wire in a magnetic field isconsumption106) Typically, only a quarter of theIJ16
Lorenzutilized.101) Many ink types can besolenoid length provides force in a
forceThis allows the magnetic field to beuseduseful direction
supplied externally to the print head,102) Fast operation107) High local currents required
for example with rare earth103) High efficiency108) Copper metalization should be
permanent magnets.104) Easy extension fromused for long electromigration lifetime
Only the current carrying wire needsingle nozzles to pagewidthand low resistivity
be fabricated on the print-head,print heads109) Pigmented inks are usually
simplifying materials requirements.infeasible
Mag-The actuator uses the giant111) Many ink types can be115) Force acts as a twisting motion120) Fischenbeck,
neto-magnetostrictive effect of materialsused116) Unusual materials such asU.S. Pat. No. 4,032,929
strictionsuch as Terfenol-D (an alloy of112) Fast operationTerfenol-D are required121) IJ25
terbium, dysprosium and iron113) Easy extension from117) High local currents required
developed at the Naval Ordnancesingle nozzles to pagewidth118) Copper metalization should be
Laboratory, hence Ter-Fe-NOL). Forprint headsused for long electromigration lifetime
best efficiency, the actuator should114) High force is availableand low resistivity
be pre-stressed to approx. 8 MPa.119) Pre-stressing may be required
SurfaceInk under positive pressure is held in122) Low power127) Requires supplementary force to130) Silverbrook, EP
tensiona nozzle by surface tension. Theconsumptioneffect drop separation0771 658 A2 and
reduc-surface tension of the ink is reduced123) Simple construction128) Requires special ink surfactantsrelated patent
tionbelow the bubble threshold, causing124) No unusual materials129) Speed may be limited byapplications
the ink to egress from the nozzle.required in fabricationsurfactant properties
125) High efficiency
126) Easy extension from
single nozzles to pagewidth
print heads
Vis-The ink viscosity is locally reduced131) Simple construction134) Requires supplementary force to139) Silverbrook, EP
cosityto select which drops are to be132) No unusual materialseffect drop separation0771 658 A2 and
reduc-ejected. A viscosity reduction can berequired in fabrication135) Requires special ink viscosityrelated patent
tionachieved electrothermally with most133) Easy extension frompropertiesapplications
inks, but special inks can besingle nozzles to pagewidth136) High speed is difficult to achieve
engineered for a 100:1 viscosityprint heads137) Requires oscillating ink pressure
reduction.138) A high temperature difference
(typically 80 degrees) is required
Acous-An acoustic wave is generated and140) Can operate without a141) Complex drive circuitry146) 1993
ticfocussed upon the drop ejectionnozzle plate142) Complex fabricationHadimioglu et al,
region.143) Low efficiencyEUP 550,192
144) Poor control of drop position147) 1993 Elrod et al,
145) Poor control of drop volumeEUP 572,220
Ther-An actuator which relies upon148) Low power157) Efficient aqueous operation160) IJ03, IJ09, IJ17,
mo-differential thermal expansion uponconsumptionrequires a thermal insulator on the hotIJ18
elasticJoule heating is used.149) Many ink types can beside161) IJ19, IJ20, IJ21,
actuatorused158) Corrosion prevention can beIJ22
150) Simple planardifficult162) IJ23, IJ24, IJ27,
fabrication159) Pigmented inks may be infeasible,IJ28
151) Small integratedas pigment particles may jam the bend163) IJ29, IJ30, IJ31,
circuit area required foractuatorIJ32
each actuator164) IJ33, IJ34, IJ35,
152) Fast operationIJ36
153) High efficiency165) IJ37, IJ38, IJ39,
154) CMOS compatibleIJ40
voltages and currents166) IJ41
155) Standard MEMS
processes can be used
156) Easy extension from
single nozzles to pagewidth
print heads
HighA material with a very high167) High force can be177) Requires special material (e.g.181) IJ09, IJ17, IJ18,
CTEcoefficient of thermal expansiongeneratedPTFE)IJ20
thermo-(CTE) such as168) PTFE is a candidate178) Requires a PTFE deposition182) IJ21, IJ22, IJ23,
elasticpolytetrafluoroethylene (PTFE) isfor low dielectric constantprocess, which is not yet standard inIJ24
actuatorused. As high CTE materials areinsulation in ULSIULSI fabs183) IJ27, IJ28, IJ29,
usually non-conductive, a heater169) Very low power179) PTFE deposition cannot beIJ30
fabricated from a conductive materialconsumptionfollowed with high temperature (above184) IJ31, IJ42, IJ43,
is incorporated. A 50 μm long PTFE170) Many ink types can be350° C.) processingIJ44
bend actuator with polysilicon heaterused180) Pigmented inks may be infeasible,
and 15 mW power input can provide171) Simple planaras pigment particles may jam the bend
180 μN force and 10 μm deflection.fabricationactuator
Actuator motions include:172) Small integrated
Bendcircuit area required for
Pusheach actuator
Buckle173) Fast operation
Rotate174) High efficiency
175) CMOS compatible
voltages and currents
176) Easy extension from
single nozzles to pagewidth
print heads
Con-A polymer with a high coefficient of185) High force can be194) Requires special materials199) IJ24
ductivethermal expansion (such as PTFE) isgenerateddevelopment (High CTE conductive
polymerdoped with conducting substances to186) Very low powerpolymer)
thermo-increase its conductivity to about 3consumption195) Requires a PTFE deposition
elasticorders of magnitude below that of187) Many ink types can beprocess, which is not yet standard in
actuatorcopper. The conducting polymerusedULSI fabs
expands when resistively heated.188) Simple planar196) PTFE deposition cannot be
Examples of conducting dopantsfabricationfollowed with high temperature (above
include:189) Small integrated350° C.) processing
Carbon nanotubescircuit area required for197) Evaporation and CVD deposition
Metal fiberseach actuatortechniques cannot be used
Conductive polymers such as doped190) Fast operation198) Pigmented inks may be infeasible,
polythiophene191) High efficiencyas pigment particles may jam the bend
Carbon granules192) CMOS compatibleactuator
voltages and currents
193) Easy extension from
single nozzles to pagewidth
print heads
ShapeA shape memory alloy such as TiNi200) High force is available206) Fatigue limits maximum number213) IJ26
memory(also known as Nitinol —Nickel(stresses of hundreds ofof cycles
alloyTitanium alloy developed at theMPa)207) Low strain (1%) is required to
Naval Ordnance Laboratory) is201) Large strain isextend fatigue resistance
thermally switched between its weakavailable (more than 3%)208) Cycle rate limited by heat
martensitic state and its high stiffness202) High corrosionremoval
austenic state. The shape of theresistance209) Requires unusual materials (TiNi)
actuator in its martensitic state is203) Simple construction210) The latent heat of transformation
deformed relative to the austenic204) Easy extension frommust be provided
shape. The shape change causessingle nozzles to pagewidth211) High current operation
ejection of a drop.print heads212) Requires pre-stressing to distort
205) Low voltage operationthe martensitic state
LinearLinear magnetic actuators include the214) Linear Magnetic218) Requires unusual semiconductor222) IJ12
Mag-Linear Induction Actuator (LIA),actuators can be constructedmaterials such as soft magnetic alloys
neticLinear Permanent Magnetwith high thrust, long travel,(e.g. CoNiFe [1])
Actu-Synchronous Actuator (LPMSA),and high efficiency using219) Some varieties also require
atorLinear Reluctance Synchronousplanar semiconductorpermanent magnetic materials such as
Actuator (LRSA), Linear Switchedfabrication techniquesNeodymium iron boron (NdFeB)
Reluctance Actuator (LSRA), and the215) Long actuator travel is220) Requires complex multi-phase
Linear Stepper Actuator (LSA).availabledrive circuitry
216) Medium force is221) High current operation
available
217) Low voltage operation

[0174] Basic Operation Mode 6

Operational
modeDescriptionAdvantagesDisadvantagesExamples
ActuatorThis is the simplest mode of223) Simple operation227) Drop repetition rate is usually230) Thermal inkjet
directly pushesoperation: the actuator directly224) No external fieldslimited to less than 10 KHz. However,231) Piezoelectric
inksupplies sufficient kinetic energy torequiredthis is not fundamental to the method,inkjet
expel the drop. The drop must have a225) Satellite drops can bebut is related to the refill method232) IJ01, IJ02, IJ03,
sufficient velocity to overcome theavoided if drop velocity isnormally usedIJ04
surface tension.less than 4 m/s228) All of the drop kinetic energy233) IJ05, IJ06, IJ07,
226) Can be efficient,must be provided by the actuatorIJ09
depending upon the actuator229) Satellite drops usually form if234) IJ11, IJ12, IJ14,
useddrop velocity is greater than 4.5 m/sIJ16
235) IJ20, IJ22, IJ23,
IJ24
236) IJ25, IJ26, IJ27,
IJ28
237) IJ29, IJ30, IJ31,
IJ32
238) IJ33, IJ34, IJ35,
IJ36
239) IJ37, IJ38, IJ39,
IJ40
240) IJ41, IJ42, IJ43,
IJ44
ProximityThe drops to be printed are selected241) Very simple print head243) Requires close proximity between246) Silverbrook, EP
by some manner (e.g. thermallyfabrication can be usedthe print head and the print media or0771 658 A2 and
induced surface tension reduction of242) The drop selectiontransfer rollerrelated patent
pressurized ink). Selected drops aremeans does not need to244) May require two print headsapplications
separated from the ink in the nozzleprovide the energy requiredprinting alternate rows of the image
by contact with the print medium or ato separate the drop from245) Monolithic color print heads are
transfer roller.the nozzledifficult
ElectrostaticThe drops to be printed are selected247) Very simple print head249) Requires very high electrostatic252) Silverbrook, EP
pull on inkby some manner (e.g. thermallyfabrication can be usedfield0771 658 A2 and
induced surface tension reduction of248) The drop selection250) Electrostatic field for small nozzlerelated patent
pressurized ink). Selected drops aremeans does not need tosizes is above air breakdownapplications
separated from the ink in the nozzleprovide the energy required251) Electrostatic field may attract dust253) Tone-Jet
by a strong electric field.to separate the drop from
the nozzle
Magnetic pullThe drops to be printed are selected254) Very simple print head256) Requires magnetic ink259) Silverbrook, EP
on inkby some manner (e.g. thermallyfabrication can be used257) Ink colors other than black are0771 658 A2 and
induced surface tension reduction of255) The drop selectiondifficultrelated patent
pressurized ink). Selected drops aremeans does not need to258) Requires very high magneticapplications
separated from the ink in the nozzleprovide the energy requiredfields
by a strong magnetic field acting onto separate the drop from
the magnetic ink.the nozzle
ShutterThe actuator moves a shutter to block260) High speed (>50 KHz)263) Moving parts are required267) IJ13, IJ17, IJ21
ink flow to the nozzle. The inkoperation can be achieved264) Requires ink pressure modulator
pressure is pulsed at a multiple of thedue to reduced refill time265) Friction and wear must be
drop ejection frequency.261) Drop timing can beconsidered
very accurate266) Stiction is possible
262) The actuator energy
can be very low
Shuttered grillThe actuator moves a shutter to block268) Actuators with small271) Moving parts are required275) IJ08, IJ15, IJ18,
ink flow through a grill to the nozzle.travel can be used272) Requires ink pressure modulatorIJ19
The shutter movement need only be269) Actuators with small273) Friction and wear must be
equal to the width of the grill holes.force can be usedconsidered
270) High speed (>50 KHz)274) Stiction is possible
operation can be achieved
PulsedA pulsed magnetic field attracts an276) Extremely low energy278) Requires an external pulsed281) IJ10
magnetic pull‘ink pusher’ at the drop ejectionoperation is possiblemagnetic field
on inkfrequency. An actuator controls a277) No heat dissipation279) Requires special materials for
pushercatch, which prevents the ink pusherproblemsboth the actuator and the ink pusher
from moving when a drop is not to be280) Complex construction
ejected.

[0175] Auxiliary Mechanism (Applied to All Nozzles) 7

Auxiliary
MechanismDescriptionAdvantagesDisadvantagesExamples
NoneThe actuator directly fires the ink282) Simplicity of285) Drop ejection energy must be286) Most inkjets,
drop, and there is no external field orconstructionsupplied by individual nozzle actuatorincluding
other mechanism required.283) Simplicity of operationpiezoelectric and
284) Small physical sizethermal bubble.
287) IJ01-IJ07, IJ09,
IJ11
288) IJ12, IJ14, IJ20,
IJ22
289) IJ23-IJ45
Oscillating inkThe ink pressure oscillates, providing290) Oscillating ink293) Requires external ink pressure296) Silverbrook, EP
pressuremuch of the drop ejection energy.pressure can provide a refilloscillator0771 658 A2 and
(includingThe actuator selects which drops arepulse, allowing higher294) Ink pressure phase and amplituderelated patent
acousticto be fired by selectively blocking oroperating speedmust be carefully controlledapplications
stimulation)enabling nozzles. The ink pressure291) The actuators may295) Acoustic reflections in the ink297) IJ08, IJ13, IJ15,
oscillation may be achieved byoperate with much lowerchamber must be designed forIJ17
vibrating the print head, or preferablyenergy298) IJ18, IJ19, IJ21
by an actuator in the ink supply.292) Acoustic lenses can be
used to focus the sound on
the nozzles
MediaThe print head is placed in close299) Low power302) Precision assembly required305) Silverbrook, EP
proximityproximity to the print medium.300) High accuracy303) Paper fibers may cause problems0771 658 A2 and
Selected drops protrude from the301) Simple print head304) Cannot print on rough substratesrelated patent
print head further than unselectedconstructionapplications
drops, and contact the print medium.
The drop soaks into the medium fast
enough to cause drop separation.
Transfer rollerDrops are printed to a transfer roller306) High accuracy309) Bulky312) Silverbrook, EP
instead of straight to the print307) Wide range of print310) Expensive0771 658 A2 and
medium. A transfer roller can also besubstrates can be used311) Complex constructionrelated patent
used for proximity drop separation.308) Ink can be dried on theapplications
transfer roller313) Tektronix hot
melt piezoelectric
inkjet
314) Any of the IJ
series
ElectrostaticAn electric field is used to accelerate315) Low power317) Field strength required for318) Silverbrook, EP
selected drops towards the print316) Simple print headseparation of small drops is near or0771 658 A2 and
medium.constructionabove air breakdownrelated patent
applications
319) Tone-Jet
DirectA magnetic field is used to accelerate320) Low power322) Requires magnetic ink324) Silverbrook, EP
magnetic fieldselected drops of magnetic ink321) Simple print head323) Requires strong magnetic field0771 658 A2 and
towards the print medium.constructionrelated patent
applications
Cross magneticThe print head is placed in a constant325) Does not require326) Requires external magnet328) IJ06, IJ16
fieldmagnetic field. The Lorenz force in amagnetic materials to be327) Current densities may be high,
current carrying wire is used to moveintegrated in the print headresulting in electromigration problems
the actuator.manufacturing process
PulsedA pulsed magnetic field is used to329) Very low power331) Complex print head construction333) IJ10
magnetic fieldcyclically attract a paddle, whichoperation is possible332) Magnetic materials required in
pushes on the ink. A small actuator330) Small print head sizeprint head
moves a catch, which selectively
prevents the paddle from moving.

[0176] Actuator Amplification or Modification Method 8

Actuator
amplificationDescriptionAdvantagesDisadvantagesExamples
NoneNo actuator mechanical amplification334) Operational simplicity335) Many actuator mechanisms have336) Thermal Bubble
is used. The actuator directly drivesinsufficient travel, or insufficient force,Inkjet
the drop ejection process.to efficiently drive the drop ejection337) IJ01, IJ02, IJ06,
processIJ07
338) IJ16, IJ25, IJ26
DifferentialAn actuator material expands more339) Provides greater travel341) High stresses are involved344) Piezoelectric
expansion bendon one side than on the other. Thein a reduced print head area342) Care must be taken that the345) IJ03, IJ09,
actuatorexpansion may be thermal,340) The bend actuatormaterials do not delaminateIJ17-IJ24
piezoelectric, magnetostrictive, orconverts a high force low343) Residual bend resulting from high346) IJ27, IJ29-IJ39,
other mechanism.travel actuator mechanismtemperature or high stress duringIJ42,
to high travel, lower forceformation347) IJ43, IJ44
mechanism.
Transient bendA trilayer bend actuator where the348) Very good351) High stresses are involved353) IJ40, IJ41
actuatortwo outside layers are identical. Thistemperature stability352) Care must be taken that the
cancels bend due to ambient349) High speed, as a newmaterials do not delaminate
temperature and residual stress. Thedrop can be fired before
actuator only responds to transientheat dissipates
heating of one side or the other.350) Cancels residual stress
of formation
Actuator stackA series of thin actuators are stacked.354) Increased travel356) Increased fabrication complexity358) Some
This can be appropriate where355) Reduced drive voltage357) Increased possibility of shortpiezoelectric ink jets
actuators require high electric fieldcircuits due to pinholes359) IJ04
strength, such as electrostatic and
piezoelectric actuators.
MultipleMultiple smaller actuators are used360) Increases the force362) Actuator forces may not add363) IJ12, IJ13, IJ18,
actuatorssimultaneously to move the ink. Eachavailable from an actuatorlinearly, reducing efficiencyIJ20
actuator need provide only a portion361) Multiple actuators can364) IJ22, IJ28, IJ42,
of the force required.be positioned to control inkIJ43
flow accurately
Linear SpringA linear spring is used to transform a365) Matches low travel367) Requires print head area for the368) IJ15
motion with small travel and highactuator with higher travelspring
force into a longer travel, lower forcerequirements
motion.366) Non-contact method
of motion transformation
Reverse springThe actuator loads a spring. When369) Better coupling to the370) Fabrication complexity372) IJ05, IJ11
the actuator is turned off, the springink371) High stress in the spring
releases. This can reverse the
force/distance curve of the actuator
to make it compatible with the
force/time requirements of the drop
ejection.
Coiled actuatorA bend actuator is coiled to provide373) Increases travel376) Generally restricted to planar377) IJ17, IJ21, IJ34,
greater travel in a reduced integrated374) Reduces integratedimplementations due to extremeIJ35
circuit area.circuit areafabrication difficulty in other
375) Planarorientations.
implementations are
relatively easy to fabricate.
Flexure bendA bend actuator has a small region378) Simple means of379) Care must be taken not to exceed382) IJ10, IJ19, IJ33
actuatornear the fixture point, which flexesincreasing travel of a bendthe elastic limit in the flexure area
much more readily than theactuator380) Stress distribution is very uneven
remainder of the actuator. The381) Difficult to accurately model with
actuator flexing is effectivelyfinite element analysis
converted from an even coiling to an
angular bend, resulting in greater
travel of the actuator tip.
GearsGears can be used to increase travel383) Low force, low travel385) Moving parts are required390) IJ13
at the expense of duration. Circularactuators can be used386) Several actuator cycles are
gears, rack and pinion, ratchets, and384) Can be fabricatedrequired
other gearing methods can be used.using standard surface387) More complex drive electronics
MEMS processes388) Complex construction
389) Friction, friction, and wear are
possible
CatchThe actuator controls a small catch.391) Very low actuator393) Complex construction396) IJ10
The catch either enables or disablesenergy394) Requires external force
movement of an ink pusher that is392) Very small actuator395) Unsuitable for pigmented inks
controlled in a bulk manner.size
Buckle plateA buckle plate can be used to change397) Very fast movement398) Must stay within elastic limits of401) S. Hirata et al,
a slow actuator into a fast motion. Itachievablethe materials for long device life“An Ink-jet Head ...”,
can also convert a high force, low399) High stresses involvedProc. IEEE MEMS,
travel actuator into a high travel,400) Generally high powerFeb. 1996, pp 418-423.
medium force motion.requirement402) IJ18, IJ27
TaperedA tapered magnetic pole can increase403) Linearizes the404) Complex construction405) IJ14
magnetic poletravel at the expense of force.magnetic force/distance
curve
LeverA lever and fulcrum is used to406) Matches low travel408) High stress around the fulcrum409) IJ32, IJ36, IJ37
transform a motion with small travelactuator with higher travel
and high force into a motion withrequirements
longer travel and lower force. The407) Fulcrum area has no
lever can also reverse the direction oflinear movement, and can
travel.be used for a fluid seal
Rotary impellerThe actuator is connected to a rotary410) High mechanical412) Complex construction414) IJ28
impeller. A small angular deflectionadvantage413) Unsuitable for pigmented inks
of the actuator results in a rotation of411) The ratio of force to
the impeller vanes, which push thetravel of the actuator can be
ink against stationary vanes and outmatched to the nozzle
of the nozzle.requirements by varying the
number of impeller vanes
Acoustic lensA refractive or diffractive (e.g. zone415) No moving parts416) Large area required418) 1993
plate) acoustic lens is used to417) Only relevant for acoustic ink jetsHadimioglu et al,
concentrate sound waves.EUP 550,192
419) 1993 Elrod et al,
EUP 572,220
SharpA sharp point is used to concentrate420) Simple construction421) Difficult to fabricate using423) Tone-jet
conductivean electrostatic field.standard VLSI processes for a surface
pointejecting ink-jet
422) Only relevant for electrostatic ink
jets

[0177] Actuator Motion 9

Actuator
motionDescriptionAdvantagesDisadvantagesExamples
VolumeThe volume of the actuator changes,424) Simple construction in425) High energy is typically required426) Hewlett-
expansionpushing the ink in all directions.the case of thermal ink jetto achieve volume expansion. ThisPackard Thermal
leads to thermal stress, cavitation, andInkjet
kogation in thermal ink jet427) Canon
implementationsBubblejet
Linear, normalThe actuator moves in a direction428) Efficient coupling to429) High fabrication complexity may430) IJ01, IJ02, IJ04,
to integratednormal to the print head surface. Theink drops ejected normal tobe required to achieve perpendicularIJ07
circuit surfacenozzle is typically in the line ofthe surfacemotion431) IJ11, IJ14
movement.
Linear, parallelThe actuator moves parallel to the432) Suitable for planar433) Fabrication complexity436) IJ12, IJ13, IJ15,
to integratedprint head surface. Drop ejection mayfabrication434) FrictionIJ33,
circuit surfacestill be normal to the surface.435) Stiction437) IJ34, IJ35, IJ36
MembraneAn actuator with a high force but438) The effective area of439) Fabrication complexity442) 1982 Howkins
pushsmall area is used to push a stiffthe actuator becomes the440) Actuator sizeU.S. Pat. No. 4,459,601
membrane that is in contact with themembrane area441) Difficulty of integration in a
ink.VLSI process
RotaryThe actuator causes the rotation of443) Rotary levers may be445) Device complexity447) IJ05, IJ08, IJ13,
some element, such a grill orused to increase travel446) May have friction at a pivot pointIJ28
impeller444) Small integrated
circuit area requirements
BendThe actuator bends when energized.448) A very small change449) Requires the actuator to be made450) 1970 Kyser et al
This may be due to differentialin dimensions can befrom at least two distinct layers, or toU.S. Pat. No. 3,946,398
thermal expansion, piezoelectricconverted to a large motion.have a thermal difference across the451) 1973 Stemme
expansion, magnetostriction, or otheractuatorU.S. Pat. No. 3,747,120
form of relative dimensional change.452) IJ03, IJ09, IJ10,
IJ19
453) IJ23, IJ24, IJ25,
IJ29
454) IJ30, IJ31, IJ33,
IJ34
455) IJ35
SwivelThe actuator swivels around a central456) Allows operation458) Inefficient coupling to the ink459) IJ06
pivot. This motion is suitable wherewhere the net linear forcemotion
there are opposite forces applied toon the paddle is zero
opposite sides of the paddle, e.g.457) Small integrated
Lorenz force.circuit area requirements
StraightenThe actuator is normally bent, and460) Can be used with461) Requires careful balance of462) IJ26, IJ32
straightens when energized.shape memory alloys wherestresses to ensure that the quiescent
the austenic phase is planarbend is accurate
Double bendThe actuator bends in one direction463) One actuator can be466) Difficult to make the drops468) IJ36, IJ37, IJ38
when one element is energized, andused to power two nozzles.ejected by both bend directions
bends the other way when another464) Reduced integratedidentical.
element is energized.circuit size.467) A small efficiency loss compared
465) Not sensitive toto equivalent single bend actuators.
ambient temperature
ShearEnergizing the actuator causes a469) Can increase the470) Not readily applicable to other471) 1985 Fishbeck
shear motion in the actuator material.effective travel ofactuator mechanismsU.S. Pat. No. 4,584,590
piezoelectric actuators
RadialThe actuator squeezes an ink472) Relatively easy to473) High force required476) 1970 Zoltan
constrictionreservoir, forcing ink from afabricate single nozzles474) InefficientU.S. Pat. No. 3,683,212
constricted nozzle.from glass tubing as475) Difficult to integrate with VLSI
macroscopic structuresprocesses
Coil/uncoilA coiled actuator uncoils or coils477) Easy to fabricate as a479) Difficult to fabricate for non-481) IJ17, IJ21, IJ34,
more tightly. The motion of the freeplanar VLSI processplanar devicesIJ35
end of the actuator ejects the ink.478) Small area required,480) Poor out-of-plane stiffness
therefore low cost
BowThe actuator bows (or buckles) in the482) Can increase the speed484) Maximum travel is constrained486) IJ16, IJ18, IJ27
middle when energized.of travel485) High force required
483) Mechanically rigid
Push-PullTwo actuators control a shutter. One487) The structure is pinned488) Not readily suitable for inkjets489) IJ18
actuator pulls the shutter, and theat both ends, so has a highwhich directly push the ink
other pushes it.out-of-plane rigidity
Curl inwardsA set of actuators curl inwards to490) Good fluid flow to the491) Design complexity492) IJ20, IJ42
reduce the volume of ink that theyregion behind the actuator
enclose.increases efficiency
Curl outwardsA set of actuators curl outwards,493) Relatively simple494) Relatively large integrated circuit495) IJ43
pressurizing ink in a chamberconstructionarea
surrounding the actuators, and
expelling ink from a nozzle in the
chamber.
IrisMultiple vanes enclose a volume of496) High efficiency498) High fabrication complexity500) IJ22
ink. These simultaneously rotate,497) Small integrated499) Not suitable for pigmented inks
reducing the volume between thecircuit area
vanes.
AcousticThe actuator vibrates at a high501) The actuator can be502) Large area required for efficient506) 1993
vibrationfrequency.physically distant from theoperation at useful frequenciesHadimioglu et al,
ink503) Acoustic coupling and crosstalkEUP 550,192
504) Complex drive circuitry507) 1993 Elrod et al,
505) Poor control of drop volume andEUP 572,220
position
NoneIn various ink jet designs the actuator508) No moving parts509) Various other tradeoffs are510) Silverbrook, EP
does not move.required to eliminate moving parts0771 658 A2 and
related patent
applications
511) Tone-jet

[0178] Nozzle Refill Method 10

Nozzle refill
methodDescriptionAdvantagesDisadvantagesExamples
Surface tensionAfter the actuator is energized, it512) Fabrication simplicity514) Low speed517) Thermal inkjet
typically returns rapidly to its normal513) Operational simplicity515) Surface tension force relatively518) Piezoelectric
position. This rapid return sucks insmall compared to actuator forceinkjet
air through the nozzle opening. The516) Long refill time usually519) IJ01-IJ07, IJ10-IJ14
ink surface tension at the nozzle thendominates the total repetition rate520) IJ16, IJ20, IJ22-IJ45
exerts a small force restoring the
meniscus to a minimum area.
ShutteredInk to the nozzle chamber is provided521) High speed523) Requires common ink pressure525) IJ08, IJ13, IJ15,
oscillating inkat a pressure that oscillates at twice522) Low actuator energy,oscillatorIJ17
pressurethe drop ejection frequency. When aas the actuator need only524) May not be suitable for526) IJ18, IJ19, IJ21
drop is to be ejected, the shutter isopen or close the shutter,pigmented inks
opened for 3 half cycles: dropinstead of ejecting the ink
ejection, actuator return, and refill.drop
Refill actuatorAfter the main actuator has ejected a527) High speed, as the528) Requires two independent529) IJ09
drop a second (refill) actuator isnozzle is actively refilledactuators per nozzle
energized. The refill actuator pushes
ink into the nozzle chamber. The
refill actuator returns slowly, to
prevent its return from emptying the
chamber again.
Positive inkThe ink is held a slight positive530) High refill rate,531) Surface spill must be prevented533) Silverbrook, EP
pressurepressure. After the ink drop istherefore a high drop532) Highly hydrophobic print head0771 658 A2 and
ejected, the nozzle chamber fillsrepetition rate is possiblesurfaces are requiredrelated patent
quickly as surface tension and inkapplications
pressure both operate to refill the534) Alternative for:
nozzle.535) IJ01-IJ07, IJ10-IJ14
536) IJ16, IJ20, IJ22-IJ45

[0179] Method of Restricting Back-Flow Through Inlet 11

Inlet back-flow
restriction
methodDescriptionAdvantagesDisadvantagesExamples
Long inletThe ink inlet channel to the nozzle537) Design simplicity540) Restricts refill rate543) Thermal inkjet
channelchamber is made long and relatively538) Operational simplicity541) May result in a relatively large544) Piezoelectric
narrow, relying on viscous drag to539) Reduces crosstalkintegrated circuit areainkjet
reduce inlet back-flow.542) Only partially effective545) IJ42, IJ43
Positive inkThe ink is under a positive pressure,546) Drop selection and548) Requires a method (such as a549) Silverbrook, EP
pressureso that in the quiescent state some ofseparation forces can benozzle rim or effective hydrophobizing,0771 658 A2 and
the ink drop already protrudes fromreducedor both) to prevent flooding of therelated patent
the nozzle.547) Fast refill timeejection surface of the print head.applications
This reduces the pressure in the550) Possible
nozzle chamber which is required tooperation of the
eject a certain volume of ink. Thefollowing:
reduction in chamber pressure results551) IJ01-IJ07, IJ09-
in a reduction in ink pushed outIJ12
through the inlet.552) IJ14, IJ16, IJ20,
IJ22,
553) IJ23-IJ34, IJ36-
IJ41
554) IJ44
BaffleOne or more baffles are placed in the555) The refill rate is not as557) Design complexity559) HP Thermal Ink
inlet ink flow. When the actuator isrestricted as the long inlet558) May increase fabricationJet
energized, the rapid ink movementmethod.complexity (e.g. Tektronix hot melt560) Tektronix
creates eddies which restrict the flow556) Reduces crosstalkPiezoelectric print heads).piezoelectric ink jet
through the inlet. The slower refill
process is unrestricted, and does not
result in eddies.
Flexible flapIn this method recently disclosed by561) Significantly reduces562) Not applicable to most inkjet565) Canon
restricts inletCanon, the expanding actuatorback-flow for edge-shooterconfigurations
(bubble) pushes on a flexible flapthermal ink jet devices563) Increased fabrication complexity
that restricts the inlet.564) Inelastic deformation of polymer
flap results in creep over extended use
Inlet filterA filter is located between the ink566) Additional advantage568) Restricts refill rate570) IJ04, IJ12, IJ24,
inlet and the nozzle chamber. Theof ink filtration569) May result in complexIJ27
filter has a multitude of small holes567) Ink filter may beconstruction571) IJ29, IJ30
or slots, restricting ink flow. Thefabricated with no
filter also removes particles whichadditional process steps
may block the nozzle.
Small inletThe ink inlet channel to the nozzle572) Design simplicity573) Restricts refill rate576) IJ02, IJ37, IJ44
compared tochamber has a substantially smaller574) May result in a relatively large
nozzlecross section than that of the nozzle,integrated circuit area
resulting in easier ink egress out of575) Only partially effective
the nozzle than out of the inlet.
Inlet shutterA secondary actuator controls the577) Increases speed of the578) Requires separate refill actuator579) IJ09
position of a shutter, closing off theink-jet print head operationand drive circuit
ink inlet when the main actuator is
energized.
The inlet isThe method avoids the problem of580) Back-flow problem is581) Requires careful design to582) IJ01, IJ03, IJ05,
located behindinlet back-flow by arranging the ink-eliminatedminimize the negative pressure behindIJ06
the ink-pushingpushing surface of the actuatorthe paddle583) IJ07, IJ10, IJ11,
surfacebetween the inlet and the nozzle.IJ14
584) IJ16, IJ22, IJ23,
IJ25
585) IJ28, IJ31, IJ32,
IJ33
586) IJ34, IJ35, IJ36,
IJ39
587) IJ40, IJ41
Part of theThe actuator and a wall of the ink588) Significant reductions590) Small increase in fabrication591) IJ07, IJ20, IJ26,
actuator moveschamber are arranged so that thein back-flow can becomplexityIJ38
to shut off themotion of the actuator closes off theachieved
inletinlet.589) Compact designs
possible
Nozzle actuatorIn some configurations of ink jet,592) Ink back-flow problem593) None related to ink back-flow on594) Silverbrook, EP
does not resultthere is no expansion or movement ofis eliminatedactuation0771 658 A2 and
in ink back-flowan actuator which may cause inkrelated patent
back-flow through the inlet.applications
595) Valve-jet
596) Tone-jet
597) IJ08, IJ13, IJ15,
IJ17
598) IJ18, IJ19, IJ21

[0180] Nozzle Clearing Method 12

Nozzle Clearing
methodDescriptionAdvantagesDisadvantagesExamples
Normal nozzleAll of the nozzles are fired599) No added complexity600) May not be sufficient to displace601) Most ink jet
firingperiodically, before the ink has aon the print headdried inksystems
chance to dry. When not in use the602) IJ01-IJ07, IJ09-
nozzles are sealed (capped) againstIJ12
air.603) IJ14, IJ16, IJ20,
The nozzle firing is usuallyIJ22
performed during a special clearing604) IJ23-IJ34, IJ36-
cycle, after first moving the printIJ45
head to a cleaning station.
Extra power toIn systems which heat the ink, but do605) Can be highly606) Requires higher drive voltage for608) Silverbrook, EP
ink heaternot boil it under normal situations,effective if the heater isclearing0771 658 A2 and
nozzle clearing can be achieved byadjacent to the nozzle607) May require larger driverelated patent
over-powering the heater and boilingtransistorsapplications
ink at the nozzle.
RapidThe actuator is fired in rapid609) Does not require extra611) Effectiveness depends612) May be used
succession ofsuccession. In some configurations,drive circuits on the printsubstantially upon the configuration ofwith:
actuator pulsesthis may cause heat build-up at theheadthe inkjet nozzle613) IJ01-IJ07, IJ09-
nozzle which boils the ink, clearing610) Can be readilyIJ11
the nozzle. In other situations, it maycontrolled and initiated by614) IJ14, IJ16, IJ20,
cause sufficient vibrations todigital logicIJ22
dislodge clogged nozzles.615) IJ23-IJ25, IJ27-
IJ34
616) IJ36-IJ45
Extra power toWhere an actuator is not normally617) A simple solution618) Not suitable where there is a hard619) May be used
ink pushingdriven to the limit of its motion,where applicablelimit to actuator movementwith:
actuatornozzle clearing may be assisted by620) IJ03, IJ09, IJ16,
providing an enhanced drive signal toIJ20
the actuator.621) IJ23, IJ24, IJ25,
IJ27
622) IJ29, IJ30, IJ31,
IJ32
623) IJ39, IJ40, IJ41,
IJ42
624) IJ43, IJ44, IJ45
AcousticAn ultrasonic wave is applied to the625) A high nozzle clearing627) High implementation cost if628) IJ08, IJ13, IJ15,
resonanceink chamber. This wave is of ancapability can be achievedsystem does not already include anIJ17
appropriate amplitude and frequency626) May be implementedacoustic actuator629) IJ18, IJ19, IJ21
to cause sufficient force at the nozzleat very low cost in systems
to clear blockages. This is easiest towhich already include
achieve if the ultrasonic wave is at aacoustic actuators
resonant frequency of the ink cavity.
Nozzle clearingA microfabricated plate is pushed630) Can clear severely631) Accurate mechanical alignment is635) Silverbrook, EP
plateagainst the nozzles. The plate has aclogged nozzlesrequired0771 658 A2 and
post for every nozzle. The array of632) Moving parts are requiredrelated patent
posts633) There is risk of damage to theapplications
nozzles
634) Accurate fabrication is required
Ink pressureThe pressure of the ink is temporarily636) May be effective637) Requires pressure pump or other640) May be used
pulseincreased so that ink streams from allwhere other methods cannotpressure actuatorwith all IJ series ink
of the nozzles. This may be used inbe used638) Expensivejets
conjunction with actuator energizing.639) Wasteful of ink
Print head wiperA flexible ‘blade’ is wiped across the641) Effective for planar643) Difficult to use if print head646) Many ink jet
print head surface. The blade isprint head surfacessurface is non-planar or very fragilesystems
usually fabricated from a flexible642) Low cost644) Requires mechanical parts
polymer, e.g. rubber or synthetic645) Blade can wear out in high
elastomer.volume print systems
Separate inkA separate heater is provided at the647) Can be effective649) Fabrication complexity650) Can be used
boiling heaternozzle although the normal drop e-where other nozzle clearingwith many IJ series
ection mechanism does not require it.methods cannot be usedink jets
The heaters do not require individual648) Can be implemented
drive circuits, as many nozzles canat no additional cost in
be cleared simultaneously, and nosome inkjet configurations
imaging is required.

[0181] Nozzle Plate Construction 13

Nozzle plate
constructionDescriptionAdvantagesDisadvantagesExamples
Electro-A nozzle plate is separately651) Fabrication simplicity652) High temperatures and pressures655) Hewlett Packard
formedfabricated from electroformed nickel,are required to bond nozzle plateThermal Inkjet
nickeland bonded to the print head653) Minimum thickness constraints
integrated circuit.654) Differential thermal expansion
LaserIndividual nozzle holes are ablated656) No masks required660) Each hole must be individually664) Canon
ablated orby an intense UV laser in a nozzle657) Can be quite fastformedBubblejet
drilledplate, which is typically a polymer658) Some control over661) Special equipment required665) 1988 Sercel et al.,
polymersuch as polyimide or polysulphonenozzle profile is possible662) Slow where there are manySPIE, Vol. 998
659) Equipment required isthousands of nozzles per print headExcimer Beam
relatively low cost663) May produce thin burrs at exitApplications, pp. 76-83
holes666) 1993 Watanabe et al.,
U.S. Pat. No. 5,208,604
SiliconA separate nozzle plate is667) High accuracy is668) Two part construction672) K. Bean, IEEE
micro-micromachined from single crystalattainable669) High costTransactions on
machinedsilicon, and bonded to the print head670) Requires precision alignmentElectron Devices,
wafer.671) Nozzles may be clogged byVol. ED-25, No. 10,
adhesive1978, pp 1185-1195
673) Xerox 1990
Hawkins et al., U.S. Pat.
No. 4,899,181
GlassFine glass capillaries are drawn from674) No expensive676) Very small nozzle sizes are678) 1970 Zoltan
capillariesglass tubing. This method has beenequipment requireddifficult to formU.S. Pat. No. 3,683,212
used for making individual nozzles,675) Simple to make single677) Not suited for mass production
but is difficult to use for bulknozzles
manufacturing of print heads with
thousands of nozzles.
Monolithic,The nozzle plate is deposited as a679) High accuracy (<1 μm)683) Requires sacrificial layer under685) Silverbrook, EP
surfacelayer using standard VLSI deposition680) Monolithicthe nozzle plate to form the nozzle0771 658 A2 and
micro-techniques. Nozzles are etched in the681) Low costchamberrelated patent
machinednozzle plate using VLSI lithography682) Existing processes can684) Surface may be fragile to theapplications
usingand etching.be usedtouch686) IJ01, IJ02, IJ04,
VLSIIJ11
lithographic687) IJ12, IJ17, IJ18,
processesIJ20
688) IJ22, IJ24, IJ27,
IJ28
689) IJ29, IJ30, IJ31,
IJ32
690) IJ33, IJ34, IJ36,
IJ37
691) IJ38, IJ39, IJ40,
IJ41
692) IJ42, IJ43, IJ44
Monolithic,The nozzle plate is a buried etch stop693) High accuracy (<1 μm)697) Requires long etch times699) IJ03, IJ05, IJ06,
etchedin the wafer. Nozzle chambers are694) Monolithic698) Requires a support waferIJ07
throughetched in the front of the wafer, and695) Low cost700) IJ08, IJ09, IJ10,
substratethe wafer is thinned from the back696) No differentialIJ13
side. Nozzles are then etched in theexpansion701) IJ14, IJ15, IJ16,
etch stop layer.IJ19
702) IJ21, IJ23, IJ25,
IJ26
No nozzleVarious methods have been tried to703) No nozzles to become704) Difficult to control drop position706) Ricoh 1995
plateeliminate the nozzles entirely, tocloggedaccuratelySekiya et al U.S. Pat. No.
prevent nozzle clogging. These705) Crosstalk problems5,412,413
include thermal bubble mechanisms707) 1993
and acoustic lens mechanismsHadimioglu et al EUP
550,192
708) 1993 Elrod et al
EUP 572,220
TroughEach drop ejector has a trough709) Reduced711) Drop firing direction is sensitive712) IJ35
through which a paddle moves. Theremanufacturing complexityto wicking.
is no nozzle plate.710) Monolithic
Nozzle slitThe elimination of nozzle holes and713) No nozzles to become714) Difficult to control drop position716) 1989 Saito et al
instead ofreplacement by a slit encompassingcloggedaccuratelyU.S. Pat. No. 4,799,068
individualmany actuator positions reduces715) Crosstalk problems
nozzlesnozzle clogging, but increases
crosstalk due to ink surface waves

[0182] Drop Ejection Direction 14

Ejection
directionDescriptionAdvantagesDisadvantagesExamples
EdgeInk flow is along the surface of the717) Simple construction722) Nozzles limited to edge725) Canon
(‘edgeintegrated circuit, and ink drops are718) No silicon etching723) High resolution is difficultBubblejet 1979 Endo
shooter’)ejected from the integrated circuitrequired724) Fast color printing requires oneet al GB patent
edge.719) Good heat sinking viaprint head per color2,007,162
substrate726) Xerox heater-in-
720) Mechanically strongpit 1990 Hawkins et
721) Ease of integratedal U.S. Pat. No. 4,899,181
circuit handing727) Tone-jet
SurfaceInk flow is along the surface of the728) No bulk silicon731) Maximum ink flow is severely732) Hewlett-
(‘roof shooter’)integrated circuit, and ink drops areetching requiredrestrictedPackard TIJ 1982
ejected from the integrated circuit729) Silicon can make anVaught et al U.S. Pat. No.
surface, normal to the plane of theeffective heat sink4,490,728
integrated circuit.730) Mechanical strength733) IJ02, IJ11, IJ12,
IJ20
734) IJ22
ThroughInk flow is through the integrated735) High ink flow738) Requires bulk silicon etching739) Silverbrook, EP
integratedcircuit, and ink drops are ejected736) Suitable for pagewidth0771 658 A2 and
circuit, forwardfrom the front surface of theprintrelated patent
(‘up shooter’)integrated circuit.737) High nozzle packingapplications
density therefore low740) IJ04, IJ17, IJ18,
manufacturing costIJ24
741) IJ27-IJ45
ThroughInk flow is through the integrated742) High ink flow745) Requires wafer thinning747) IJ01, IJ03, IJ05,
integratedcircuit, and ink drops are ejected743) Suitable for pagewidth746) Requires special handling duringIJ06
circuit, reversefrom the rear surface of theprintmanufacture748) IJ07, IJ08, IJ09,
(‘downintegrated circuit.744) High nozzle packingIJ10
shooter’)density therefore low749) IJ13, IJ14, IJ15,
manufacturing costIJ16
750) IJ19, IJ21, IJ23,
IJ25
751) IJ26
ThroughInk flow is through the actuator,752) Suitable for753) Pagewidth print heads require756) Epson Stylus
actuatorwhich is not fabricated as part of thepiezoelectric print headsseveral thousand connections to drive757) Tektronix hot
same substrate as the drivecircuitsmelt piezoelectric ink
transistors.754) Cannot be manufactured injets
standard CMOS fabs
755) Complex assembly required

[0183] Ink Type 15

Ink typeDescriptionAdvantagesDisadvantagesExamples
Aqueous, dyeWater based ink which typically758) Environmentally760) Slow drying765) Most existing
contains: water, dye, surfactant,friendly761) Corrosiveinkjets
humectant, and biocide.759) No odor762) Bleeds on paper766) All IJ series ink
Modern ink dyes have high water-763) May strikethroughjets
fastness, light fastness764) Cockles paper767) Silverbrook, EP
0771 658 A2 and
related patent
applications
Aqueous,Water based ink which typically768) Environmentally773) Slow drying778) IJ02, IJ04, IJ21,
pigmentcontains: water, pigment, surfactant,friendly774) CorrosiveIJ26
humectant, and biocide.769) No odor775) Pigment may clog nozzles779) IJ27, IJ30
Pigments have an advantage in770) Reduced bleed776) Pigment may clog actuator780) Silverbrook, EP
reduced bleed, wicking and771) Reduced wickingmechanisms0771 658 A2 and
strikethrough.772) Reduced strikethrough777) Cockles paperrelated patent
applications
781) Piezoelectric
ink-jets
782) Thermal ink jets
(with significant
restrictions)
Methyl EthylMEK is a highly volatile solvent used783) Very fast drying785) Odorous787) All IJ series ink
Ketone (MEK)for industrial printing on difficult784) Prints on various786) Flammablejets
surfaces such as aluminum cans.substrates such as metals
and plastics
AlcoholAlcohol based inks can be used788) Fast drying792) Slight odor794) All IJ series ink
(ethanol, 2-where the printer must operate at789) Operates at sub-793) Flammablejets
butanol, andtemperatures below the freezingfreezing temperatures
others)point of water. An example of this is790) Reduced paper cockle
in-camera consumer photographic791) Low cost
printing.
Phase changeThe ink is solid at room temperature,795) No drying time-ink801) High viscosity807) Tektronix hot
(hot melt)and is melted in the print head beforeinstantly freezes on the print802) Printed ink typically has a ‘waxy’melt piezoelectric ink
jetting. Hot melt inks are usually waxmediumfeeljets
based, with a melting point around796) Almost any print803) Printed pages may ‘block’808) 1989 Nowak U.S.
80° C. After jetting the ink freezesmedium can be used804) Ink temperature may be above thePat. No. 4,820,346
almost instantly upon contacting the797) No paper cocklecurie point of permanent magnets809) All IJ series ink
print medium or a transfer roller.occurs805) Ink heaters consume powerjets
798) No wicking occurs806) Long warm-up time
799) No bleed occurs
800) No strikethrough
occurs
OilOil based inks are extensively used in810) High solubility813) High viscosity: this is a815) All IJ series ink
offset printing. They have advantagesmedium for some dyessignificant limitation for use in inkjets,jets
in improved characteristics on paper811) Does not cockle paperwhich usually require a low viscosity.
(especially no wicking or cockle). Oil812) Does not wick throughSome short chain and multi-branched
soluble dies and pigments arepaperoils have a sufficiently low viscosity.
required.814) Slow drying
MicroemulsionA microemulsion is a stable, self816) Stops ink bleed820) Viscosity higher than water823) All IJ series ink
forming emulsion of oil, water, and817) High dye solubility821) Cost is slightly higher than waterjets
surfactant. The characteristic drop818) Water, oil, andbased ink
size is less than 100 nm, and isamphiphilic soluble dies can822) High surfactant concentration
determined by the preferredbe usedrequired (around 5%)
curvature of the surfactant.819) Can stabilize pigment
suspensions

[0184] Ink Jet Printing

[0185] A large number of new forms of ink jet printers have been developed to facilitate alternative ink jet technologies for the image processing and data distribution system. Various combinations of ink jet devices can be included in printer devices incorporated as part of the present invention. Australian Provisional Patent Applications relating to these ink jets which are specifically incorporated by cross reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 16

Australian
ProvisionalUS Patent/Patent Application
NumberFiling DateTitleand Filing Date
PO806615-Jul-97Image Creation Method and Apparatus (IJ01)6,227,652
(Jul. 10, 1998)
PO807215-Jul-97Image Creation Method and Apparatus (IJ02)6,213,588
(Jul. 10, 1998)
PO804015-Jul-97Image Creation Method and Apparatus (IJ03)6,213,589
(Jul. 10, 1998)
PO807115-Jul-97Image Creation Method and Apparatus (IJ04)6,231,163
(Jul. 10, 1998)
PO804715-Jul-97Image Creation Method and Apparatus (IJ05)6,247,795
(Jul. 10, 1998)
PO803515-Jul-97Image Creation Method and Apparatus (IJ06)6,394,581
(Jul. 10, 1998)
PO804415-Jul-97Image Creation Method and Apparatus (IJ07)6,244,691
(Jul. 10, 1998)
PO806315-Jul-97Image Creation Method and Apparatus (IJ08)6,257,704
(Jul. 10, 1998)
PO805715-Jul-97Image Creation Method and Apparatus (IJ09)6,416,168
(Jul. 10, 1998)
PO805615-Jul-97Image Creation Method and Apparatus (IJ10)6,220,694
(Jul. 10, 1998)
PO806915-Jul-97Image Creation Method and Apparatus (IJ11)6,257,705
(Jul. 10, 1998)
PO804915-Jul-97Image Creation Method and Apparatus (IJ12)6,247,794
(Jul. 10, 1998)
PO803615-Jul-97Image Creation Method and Apparatus (IJ13)6,234,610
(Jul. 10, 1998)
PO804815-Jul-97Image Creation Method and Apparatus (IJ14)6,247,793
(Jul. 10, 1998)
PO807015-Jul-97Image Creation Method and Apparatus (IJ15)6,264,306
(Jul. 10, 1998)
PO806715-Jul-97Image Creation Method and Apparatus (IJ16)6,241,342
(Jul. 10, 1998)
PO800115-Jul-97Image Creation Method and Apparatus (IJ17)6,247,792
(Jul. 10, 1998)
PO803815-Jul-97Image Creation Method and Apparatus (IJ18)6,264,307
(Jul. 10, 1998)
PO803315-Jul-97Image Creation Method and Apparatus (IJ19)6,254,220
(Jul. 10, 1998)
PO800215-Jul-97Image Creation Method and Apparatus (IJ20)6,234,611
(Jul. 10, 1998)
PO806815-Jul-97Image Creation Method and Apparatus (IJ21)6,302,528)
(Jul. 10, 1998)
PO806215-Jul-97Image Creation Method and Apparatus (IJ22)6,283,582
(Jul. 10, 1998)
PO803415-Jul-97Image Creation Method and Apparatus (IJ23)6,239,821
(Jul. 10, 1998)
PO803915-Jul-97Image Creation Method and Apparatus (IJ24)6,338,547
(Jul. 10, 1998)
PO804115-Jul-97Image Creation Method and Apparatus (IJ25)6,247,796
(Jul. 10, 1998)
PO800415-Jul-97Image Creation Method and Apparatus (IJ26)09/113,122
(Jul. 10, 1998)
PO803715-Jul-97Image Creation Method and Apparatus (IJ27)6,390,603
(Jul. 10, 1998)
PO804315-Jul-97Image Creation Method and Apparatus (IJ28)6,362,843
(Jul. 10, 1998)
PO804215-Jul-97Image Creation Method and Apparatus (IJ29)6,293,653
(Jul. 10, 1998)
PO806415-Jul-97Image Creation Method and Apparatus (IJ30)6,312,107
(Jul. 10, 1998)
PO938923-Sep-97Image Creation Method and Apparatus (IJ31)6,227,653
(Jul. 10, 1998)
PO939123-Sep-97Image Creation Method and Apparatus (IJ32)6,234,609
(Jul. 10, 1998)
PP088812-Dec-97Image Creation Method and Apparatus (IJ33)6,238,040
(Jul. 10, 1998)
PP089112-Dec-97Image Creation Method and Apparatus (IJ34)6,188,415
(Jul. 10, 1998)
PP089012-Dec-97Image Creation Method and Apparatus (IJ35)6,227,654
(Jul. 10, 1998)
PP087312-Dec-97Image Creation Method and Apparatus (IJ36)6,209,989
(Jul. 10, 1998)
PP099312-Dec-97Image Creation Method and Apparatus (IJ37)6,247,791
(Jul. 10, 1998)
PP089012-Dec-97Image Creation Method and Apparatus (IJ38)6,336,710
(Jul. 10, 1998)
PP139819-Jan-98An Image Creation Method and Apparatus6,217,153
(IJ39)(Jul. 10, 1998)
PP259225-Mar-98An Image Creation Method and Apparatus6,416,167
(IJ40)(Jul. 10, 1998)
PP259325-Mar-98Image Creation Method and Apparatus (IJ41)6,243,113
(Jul. 10, 1998)
PP39919-Jun-98Image Creation Method and Apparatus (IJ42)6,283,581
(Jul. 10, 1998)
PP39879-Jun-98Image Creation Method and Apparatus (IJ43)6,247,790
(Jul. 10, 1998)
PP39859-Jun-98Image Creation Method and Apparatus (IJ44)6,260,953
(Jul. 10, 1998)
PP39839-Jun-98Image Creation Method and Apparatus (IJ45)6,267,469
(Jul. 10, 1998)

[0186] Ink Jet Manufacturing

[0187] Further, the present application may utilize advanced semiconductor fabrication techniques in the construction of large arrays of ink jet printers. Suitable manufacturing techniques are described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 17

Australian
ProvisionalUS Patent/Patent Application
NumberFiling DateTitleand Filing Date
PO793515-Jul-97A Method of Manufacture of an Image Creation6,224,780
Apparatus (IJM01)(Jul. 10, 1998)
PO793615-Jul-97A Method of Manufacture of an Image Creation6,235,212
Apparatus (IJM02)(Jul. 10, 1998)
PO793715-Jul-97A Method of Manufacture of an Image Creation6,280,643
Apparatus (IJM03)(Jul. 10, 1998)
PO806115-Jul-97A Method of Manufacture of an Image Creation6,284,147
Apparatus (IJM04)(Jul. 10, 1998)
PO805415-Jul-97A Method of Manufacture of an Image Creation6,214,244
Apparatus (IJM05)(Jul. 10, 1998)
PO806515-Jul-97A Method of Manufacture of an Image Creation6,071,750
Apparatus (IJM06)(Jul. 10, 1998)
PO805515-Jul-97A Method of Manufacture of an Image Creation6,267,905
Apparatus (IJM07)(Jul. 10, 1998)
PO805315-Jul-97A Method of Manufacture of an Image Creation6,251,298
Apparatus (IJM08)(Jul. 10, 1998)
PO807815-Jul-97A Method of Manufacture of an Image Creation6,258,285
Apparatus (IJM09)(Jul. 10, 1998)
PO793315-Jul-97A Method of Manufacture of an Image Creation6,225,138
Apparatus (IJM10)(Jul. 10, 1998)
PO795015-Jul-97A Method of Manufacture of an Image Creation6,241,904
Apparatus (IJM11)(Jul. 10, 1998)
PO794915-Jul-97A Method of Manufacture of an Image Creation6,299,786
Apparatus (IJM12)(Jul. 10, 1998)
PO806015-Jul-97A Method of Manufacture of an Image Creation09/113,124
Apparatus (IJM13)(Jul. 10, 1998)
PO805915-Jul-97A Method of Manufacture of an Image Creation6,231,773
Apparatus (IJM14)(Jul. 10, 1998)
PO807315-Jul-97A Method of Manufacture of an Image Creation6,190,931
Apparatus (IJM15)(Jul. 10, 1998)
PO807615-Jul-97A Method of Manufacture of an Image Creation6,248,249
Apparatus (IJM16)(Jul. 10, 1998)
PO807515-Jul-97A Method of Manufacture of an Image Creation6,290,862
Apparatus (IJM17)(Jul. 10, 1998)
PO807915-Jul-97A Method of Manufacture of an Image Creation6,241,906
Apparatus (IJM18)(Jul. 10, 1998)
PO805015-Jul-97A Method of Manufacture of an Image Creation09/113,116
Apparatus (IJM19)(Jul. 10, 1998)
PO805215-Jul-97A Method of Manufacture of an Image Creation6,241,905
Apparatus (IJM20)(Jul. 10, 1998)
PO794815-Jul-97A Method of Manufacture of an Image Creation6,451,216
Apparatus (IJM21)(Jul. 10, 1998)
PO795115-Jul-97A Method of Manufacture of an Image Creation6,231,772
Apparatus (IJM22)(Jul. 10, 1998)
PO807415-Jul-97A Method of Manufacture of an Image Creation6,274,056
Apparatus (IJM23)(Jul. 10, 1998)
PO794115-Jul-97A Method of Manufacture of an Image Creation6,290,861
Apparatus (IJM24)(Jul. 10, 1998)
PO807715-Jul-97A Method of Manufacture of an Image Creation6,248,248
Apparatus (IJM25)(Jul. 10, 1998)
PO805815-Jul-97A Method of Manufacture of an Image Creation6,306,671
Apparatus (IJM26)(Jul. 10, 1998)
PO805115-Jul-97A Method of Manufacture of an Image Creation6,331,258
Apparatus (IJM27)(Jul. 10, 1998)
PO804515-Jul-97A Method of Manufacture of an Image Creation6,110,754
Apparatus (IJM28)(Jul. 10, 1998)
PO795215-Jul-97A Method of Manufacture of an Image Creation6,294,101
Apparatus (IJM29)(Jul. 10, 1998)
PO804615-Jul-97A Method of Manufacture of an Image Creation6,416,679
Apparatus (IJM30)(Jul. 10, 1998)
PO850311-Aug-97A Method of Manufacture of an Image Creation6,264,849
Apparatus (IJM30a)(Jul. 10, 1998)
PO939023-Sep-97A Method of Manufacture of an Image Creation6,254,793
Apparatus (IJM31)(Jul. 10, 1998)
PO939223-Sep-97A Method of Manufacture of an Image Creation6,235,211
Apparatus (IJM32)(Jul. 10, 1998)
PP088912-Dec-97A Method of Manufacture of an Image Creation6,235,211
Apparatus (IJM35)(Jul. 10, 1998)
PP088712-Dec-97A Method of Manufacture of an Image Creation6,264,850
Apparatus (IJM36)(Jul. 10, 1998)
PP088212-Dec-97A Method of Manufacture of an Image Creation6,258,284
Apparatus (IJM37)(Jul. 10, 1998)
PP087412-Dec-97A Method of Manufacture of an Image Creation6,258,284
Apparatus (IJM38)(Jul. 10, 1998)
PP139619-Jan-98A Method of Manufacture of an Image Creation6,228,668
Apparatus (IJM39)(Jul. 10, 1998)
PP259125-Mar-98A Method of Manufacture of an Image Creation6,180,427
Apparatus (IJM41)(Jul. 10, 1998)
PP39899-Jun-98A Method of Manufacture of an Image Creation6,171,875
Apparatus (IJM40)(Jul. 10, 1998)
PP39909-Jun-98A Method of Manufacture of an Image Creation6,267,904
Apparatus (IJM42)(Jul. 10, 1998)
PP39869-Jun-98A Method of Manufacture of an Image Creation6,245,247
Apparatus (IJM43)(Jul. 10, 1998)
PP39849-Jun-98A Method of Manufacture of an Image Creation6,245,247
Apparatus (IJM44)(Jul. 10, 1998)
Apparatus (IJM44)
PP39829-Jun-98A Method of Manufacture of an Image Creation6,231,148
Apparatus (IJM45)(Jul. 10, 1998)

[0188] Fluid Supply

[0189] Further, the present application may utilize an ink delivery system to the ink jet head. Delivery systems relating to the supply of ink to a series of ink jet nozzles are described in the following Australian provisional patent specifications, the disclosure of which are hereby incorporated by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 18

AustralianUS Patent/Patent
ProvisionalApplication and
NumberFiling DateTitleFiling Date
PO800315-Jul-97Supply Method and6,350,023
Apparatus (F1)(Jul. 10, 1998)
PO800515-Jul-97Supply Method and6,318,849
Apparatus (F2)(Jul. 10, 1998)
PO940423-Sep-97A Device and09/113,101
Method (F3)(Jul. 10, 1998)

[0190] MEMS Technology

[0191] Further, the present application may utilize advanced semiconductor microelectromechanical techniques in the construction of large arrays of ink jet printers. Suitable microelectromechanical techniques are described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 19

AustralianUS Patent/Patent
ProvisionalApplication and
NumberFiling DateTitleFiling Date
PO794315-Jul-97A device (MEMS01)
PO800615-Jul-97A device (MEMS02)6,087,638
(Jul. 10, 1998)
PO800715-Jul-97A device (MEMS03)09/113,093
(Jul. 10, 1998)
PO800815-Jul-97A device (MEMS04)6,340,222
(Jul. 10, 1998)
PO801015-Jul-97A device (MEMS05)6,041,600
(Jul. 10, 1998)
PO801115-Jul-97A device (MEMS06)6,299,300
(Jul. 10, 1998)
PO794715-Jul-97A device (MEMS07)6,067,797
(Jul. 10, 1998)
PO794515-Jul-97A device (MEMS08)09/113,081
(Jul. 10, 1998)
PO794415-Jul-97A device (MEMS09)6,286,935
(Jul. 10, 1998)
PO794615-Jul-97A device (MEMS10)6,044,646
(Jul. 10, 1998)
PO939323-Sep-97A Device and09/113,065
Method (MEMS11)(Jul. 10, 1998)
PP087512-Dec-97A Device (MEMS12)09/113,078
(Jul. 10, 1998)
PP089412-Dec-97A Device and09/113,075
Method (MEMS13)(Jul. 10, 1998)

[0192] IR Technologies

[0193] Further, the present application may include the utilization of a disposable camera system such as those described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 20

Australian
ProvisionalUS Patent/Patent Application and
NumberFiling DateTitleFiling Date
PP089512-Dec-97An Image Creation Method and Apparatus6,231,148
(IR01)(Jul. 10, 1998)
PP087012-Dec-97A Device and Method (IR02)09/113,106
(Jul. 10, 1998)
PP086912-Dec-97A Device and Method (IR04)6,293,658
(Jul. 10, 1998)
PP088712-Dec-97Image Creation Method and Apparatus09/113,104
(IR05)(Jul. 10, 1998)
PP088512-Dec-97An Image Production System (IR06)6,238,033
(Jul. 10, 1998)
PP088412-Dec-97Image Creation Method and Apparatus6,312,070
(IR10)(Jul. 10, 1998)
PP088612-Dec-97Image Creation Method and Apparatus6,238,111
(IR12)(Jul. 10, 1998)
PP087112-Dec-97A Device and Method (IR13)09/113,086
(Jul. 10, 1998)
PP087612-Dec-97An Image Processing Method and Apparatus09/113,094
(IR14)(Jul. 10, 1998)
PP087712-Dec-97A Device and Method (IR16)6,378,970
(Jul. 10, 1998)
PP087812-Dec-97A Device and Method (IR17)6,196,739
(Jul. 10, 1998)
PP087912-Dec-97A Device and Method (IR18)09/112,774
(Jul. 10, 1998)
PP088312-Dec-97A Device and Method (IR19)6,270,182
(Jul. 10, 1998)
PP088012-Dec-97A Device and Method (IR20)6,152,619
(Jul. 10, 1998)
PP088112-Dec-97A Device and Method (IR21)09/113,092
(Jul. 10, 1998)

[0194] DotCard Technologies

[0195] Further, the present application may include the utilization of a data distribution system such as that described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 21

AustralianUS Patent/Patent
ProvisionalApplication and
NumberFiling DateTitleFiling Date
PP237016-Mar-98Data Processing09/112,781
Method and(Jul. 10, 1998)
Apparatus
(Dot01)
PP237116-Mar-98Data Processing09/113,052
Method and(Jul. 10, 1998
Apparatus
(Dot02)

[0196] Artcam Technologies

[0197] Further, the present application may include the utilization of camera and data processing techniques such as an Artcam type device as described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. 22

Australian
ProvisionalUS Patent/Patent Application and
NumberFiling DateTitleFiling Date
PO799115-Jul-97Image Processing Method and Apparatus09/113,060
(ART01)(Jul. 10, 1998)
PO798815-Jul-97Image Processing Method and Apparatus6,476,863
(ART02)(Jul. 10, 1998)
PO799315-Jul-97Image Processing Method and Apparatus09/113,073
(ART03)(Jul. 10, 1998)
PO939523-Sep-97Data Processing Method and Apparatus6,322,181
(ART04)(Jul. 10, 1998)
PO801715-Jul-97Image Processing Method and Apparatus09/112,747
(ART06)(Jul. 10, 1998)
PO801415-Jul-97Media Device (ART07)6,227,648
(Jul. 10, 1998)
PO802515-Jul-97Image Processing Method and Apparatus09/112,750
(ART08)(Jul. 10, 1998)
PO803215-Jul-97Image Processing Method and Apparatus09/112,746
(ART09)(Jul. 10, 1998)
PO799915-Jul-97Image Processing Method and Apparatus09/112,743
(ART10)(Jul. 10, 1998)
PO799815-Jul-97Image Processing Method and Apparatus09/112,742
(ART11)(Jul. 10, 1998)
PO803115-Jul-97Image Processing Method and Apparatus09/112,741
(ART12)(Jul. 10, 1998)
PO803015-Jul-97Media Device (ART13)6,196,541
(Jul. 10, 1998)
PO799715-Jul-97Media Device (ART15)6,195,150
(Jul. 10, 1998)
PO797915-Jul-97Media Device (ART16)6,362,868
(Jul. 10, 1998)
PO801515-Jul-97Media Device (ART17)09/112,738
(Jul. 10, 1998)
PO797815-Jul-97Media Device (ART18)09/113,067
(Jul. 10, 1998)
PO798215-Jul-97Data Processing Method and Apparatus6,431,669
(ART19)(Jul. 10, 1998
PO798915-Jul-97Data Processing Method and Apparatus6,362,869
(ART20)(Jul. 10, 1998
PO801915-Jul-97Media Processing Method and Apparatus6,472,052
(ART21)(Jul. 10, 1998
PO798015-Jul-97Image Processing Method and Apparatus6,356,715
(ART22)(Jul. 10, 1998)
PO801815-Jul-97Image Processing Method and Apparatus09/112,777
(ART24)(Jul. 10, 1998)
PO793815-Jul-97Image Processing Method and Apparatus09/113,224
(ART25)(Jul. 10, 1998)
PO801615-Jul-97Image Processing Method and Apparatus6,366,693
(ART26)(Jul. 10, 1998)
PO802415-Jul-97Image Processing Method and Apparatus6,329,990
(ART27)(Jul. 10, 1998)
PO794015-Jul-97Data Processing Method and Apparatus09/113,072
(ART28)(Jul. 10, 1998)
PO793915-Jul-97Data Processing Method and Apparatus09/112,785
(ART29)(Jul. 10, 1998)
PO850111-Aug-97Image Processing Method and Apparatus6,137,500
(ART30)(Jul. 10, 1998)
PO850011-Aug-97Image Processing Method and Apparatus09/112,796
(ART31)(Jul. 10, 1998)
PO798715-Jul-97Data Processing Method and Apparatus09/113,071
(ART32)(Jul. 10, 1998)
PO802215-Jul-97Image Processing Method and Apparatus6,398,328
(ART33)(Jul. 10, 1998
PO849711-Aug-97Image Processing Method and Apparatus09/113,090
(ART34)(Jul. 10, 1998)
PO802015-Jul-97Data Processing Method and Apparatus6,431,704
(ART38)(Jul. 10, 1998
PO802315-Jul-97Data Processing Method and Apparatus09/113,222
(ART39)(Jul. 10, 1998)
PO850411-Aug-97Image Processing Method and Apparatus09/112,786
(ART42)(Jul. 10, 1998)
PO800015-Jul-97Data Processing Method and Apparatus6,415,054
(ART43)(Jul. 10, 1998)
PO797715-Jul-97Data Processing Method and Apparatus09/112,782
(ART44)(Jul. 10, 1998)
PO793415-Jul-97Data Processing Method and Apparatus09/113,056
(ART45)(Jul. 10, 1998)
PO799015-Jul-97Data Processing Method and Apparatus09/113,059
(ART46)(Jul. 10, 1998)
PO849911-Aug-97Image Processing Method and Apparatus6,486,886
(ART47)(Jul. 10, 1998)
PO850211-Aug-97Image Processing Method and Apparatus6,381,361
(ART48)(Jul. 10, 1998)
PO798115-Jul-97Data Processing Method and Apparatus6,317,192
(ART50)(Jul. 10, 1998
PO798615-Jul-97Data Processing Method and Apparatus09/113,057
(ART51)(Jul. 10, 1998)
PO798315-Jul-97Data Processing Method and Apparatus09/113,054
(ART52)(Jul. 10, 1998)
PO802615-Jul-97Image Processing Method and Apparatus09/112,752
(ART53)(Jul 10, 1998)
PO802715-Jul-97Image Processing Method and Apparatus09/112,759
(ART54)(Jul. 10, 1998)
PO802815-Jul-97Image Processing Method and Apparatus09/112,757
(ART56)(Jul. 10, 1998)
PO939423-Sep-97Image Processing Method and Apparatus6,357,135
(ART57)(Jul. 10, 1998
PO939623-Sep-97Data Processing Method and Apparatus09/113,107
(ART58)(Jul. 10, 1998)
PO939723-Sep-97Data Processing Method and Apparatus6,271,931
(ART59)(Jul. 10, 1998)
PO939823-Sep-97Data Processing Method and Apparatus6,353,772
(ART60)(Jul. 10, 1998)
PO939923-Sep-97Data Processing Method and Apparatus6,106,147
(ART61)(Jul. 10, 1998)
PO940023-Sep-97Data Processing Method and Apparatus09/112,790
(ART62)(Jul. 10, 1998)
PO940123-Sep-97Data Processing Method and Apparatus6,304,291
(ART63)(Jul. 10, 1998)
PO940223-Sep-97Data Processing Method and Apparatus09/112,788
(ART64)(Jul. 10, 1998)
PO940323-Sep-97Data Processing Method and Apparatus6,305,770
(ART65)(Jul. 10, 1998)
PO940523-Sep-97Data Processing Method and Apparatus6,289,262
(ART66)(Jul. 10, 1998)
PP095916-Dec-97A Data Processing Method and Apparatus6,315,200
(ART68)(Jul. 10, 1998)
PP139719-Jan-98A Media Device (ART69)6,217,165
(Jul. 10, 1998)