Title:
ELECTRO-MECHANICAL READ HEAD
United States Patent 3714398


Abstract:
An electromechanical read head includes a plurality of juxtaposed scanning the card, for scanning raised or embossed characters, such as the embossed characters of a credit card. The juxtaposed elements are mounted between parallel side walls of the head and are free to move independently of each other. The walls extend downwardly and define a channel therebetween for receiving therebetween a line of embossed characters, the walls physically engaging the upper and lower extremes of the embossed characters. The path of travel of the card through the scan head, and thus the scan path of each scanning element, is thereby defined. Each of the scanning elements comprises an arm of resilient material including a scanning tip or wiper which is normally biased toward the surface of the card the arm thereby being deflected upwardly when the tip is raised upon engaging a segment of a character in its scan path. Electrical switching means associated with each element respond to the deflection thereof to produce an electrical output signal corresponding to the mechanical scanning of segments of the character in the corresponding scan path. The plural, simultaneously produced output signals are then processed for character recognition.



Inventors:
BROCK A
Application Number:
05/128379
Publication Date:
01/30/1973
Filing Date:
03/26/1971
Assignee:
DATA CARD CORP,US
Primary Class:
Other Classes:
235/485
International Classes:
G06K7/04; G06K9/18; (IPC1-7): G06K7/015; G06K7/04; G06K7/10
Field of Search:
235/61
View Patent Images:
US Patent References:
3612833EMBOSSED CARD READING DEVICE1971-10-12Davis
3612832EMBOSSMENT READERS FOR IDENTIFICATION CARDS AND THE LIKE1971-10-12Goldstein et al.
3611292CREDIT CARD VALIDATION SYSTEM1971-10-05Brown et al.
3542979CARD READER CONTACT ASSEMBLY1970-11-24Collier
2374790Sensing means1945-05-01Terry



Primary Examiner:
Cook, Daryl W.
Claims:
What is claimed is

1. Apparatus for mechanically scanning embossed charac-ters presented thereto on a carrier and producing in response to the scanning thereof electrical output signals for processing by automatic character recognition circuits, comprising:

2. Apparatus as recited in claim 1, wherein said resilient arms of said plurality of scanning elements include a corresponding plurality of respectively associated, successively displaced tabs projecting therefrom and aligned with the plurality of respectively corresponding light beam paths, each of said tabs being operable to interrupt the associated light beam path when the arm is deflected upwardly in response to the scanning tip thereof engaging a character segment in its corresponding scan path.

3. Apparatus as recited in claim 1, wherein:

4. Apparatus for mechanically scanning embossed characters presented thereto on a carrier and producing in response to the scanning thereof electrical output signals for processing by automatic character recognition circuits, comprising:

5. Apparatus as recited in claim 4, further comprising:

6. Apparatus as recited in claim 5, wherein said side walls define therebetween a channel of a height corresponding to the height of the embossed characters to be scanned and engaging therebetween the upper and lower edges of each character of a line thereof to be scanned, thereby to automatically align said line of characters for scanning of each character, in succession, by said scanning elements in said respectively corresponding parallel scan paths.

7. Apparatus as recited in claim 6, wherein said side walls are reduced in thickness along the longitudinally extending lower edges thereof on the exterior surface of the side wall.

8. Apparatus for mechanically scanning raised characters presented by a support member and producing in response to the scanning thereof electrical output signals indicative of the scanned characters, comprising:

9. Apparatus as claimed in claim 8, further comprising:

Description:
BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to read heads for automatic character recognition, and, more particularly, to a read head for reading embossed characters such as of the type provided on conventional credit cards and the like.

2. State of the Prior Art

In view of the continually expanding use of credit cards, a substantial need has developed for apparatus capable of automatically reading the embossed characters of credit cards. Such apparatus must be highly reliable to assure that the information, such as account identification, derived from reading the card is correct. Typically, of course, the purpose of reading the credit card is to verify the status of the account or to effect a credit or debit of that account in accordance with a commercial transaction for which the card is being used. In conjunction with the automatic reading of the credit cards, there accordingly have been developed automatic data transmission and processing systems for appropriately processing the transaction as relates to that account.

Accordingly, there have been provided heretofore various types of apparatus for automatically reading embossed characters. One type utilizes optical scanning means which effect sensing of the embossed characters in accordance with the varying angles of reflection of a beam of light incident thereon and which is caused to scan the characters in a progressive scan path. The optical systems are typically quite complex. For example, some systems employ one or more slotted discs which are rotated in a controlled synchronized manner so as to produce a beam of light which traces the desired scan path. Other such optical systems require the use of a so-called flying spot cathode ray tube, the beam of which is electronically deflected to trace through the desired scan path.

Such optical systems are undesirable, not only in view of the expense and complexity thereof, but also because of their unreliability. More particularly, the unreliability arises due to the nature of the documents being read and their manner of use. For example, credit cards are subject to handling both by the user as well as by a clerk or other personnel in conjunction with any of various transactions. The cards usually are formed of a plastic-type material having a relatively high reflectivity. However, cards of different commercial enterprises are frequently made with different background colors, and some cards have varying color patterns. These varying color characteristics introduce varying responses in optical scanning apparatus, thereby introducing a source of error in the reading thereof, and at a minimum requiring compensation circuitry to minimize the effect of these variables.

The handling of the cards by the holder thereof, as well as their use in imprinting credit forms, typically causes the embossed characters to become dirty and causes some abrasion of the surface thereof, whereby the reflectivity characteristics may vary from one character to another and even within a single character on a given card, and from card to card. These numerous variations in the optical characteristics of the embossed characters thus introduce further sources of error in optical reading apparatus.

Other types of automatic readers for embossed characters include complex mechanical systems having a large number of sensing elements which are displaced in accordance with the configuration of each character. Such mechanical apparatus particularly have been developed for use with systems which require sensing of the entire configuration of a character at one time for recognition of the character. This type of mechanical apparatus is likewise quite complex, requiring a large number of individually operable sensing elements. Further, position control means must be provided to assure that a single character is presented in its entirety to the sensing elements, for each character of the card in succession, which is to be read. Thus the transporting and positioning means associated with the sensing structure is likewise quite complex.

These and other prior art apparatus for sensing embossed characters have therefore failed to satisfy the need for a low-cost, yet reliable automatic embossed character reader.

SUMMARY OF THE INVENTION

The electromechanical read head of the invention overcomes the above and other defects of the prior art apparatus heretofore developed for the automatic reading of embossed characters. Whereas the read, or scan head of the invention is herein disclosed in a specific embodiment for reading such characters from credit cards, it is to be appreciated that the scan head may be utilized for reading of any type of embossed or raised characters.

The scan head of the invention is of greatly simplified mechanical construction as contrasted to prior art scan heads, and yet is highly accurate and reliable in use. The output signals derived from the scan head may be utilized by any of various character recognition systems. Suitable methods and associated systems for effecting processing of the signals for character recognition are disclosed in the copending applications of Raymond J. Deschenes entitled CHARACTER RECOGNITION METHOD AND SYSTEM and of John A. Cribbs, Arthur B. Abeling and Kenneth H. Breeden, entitled CHARACTER RECOGNITION METHOD AND SYSTEM WITH STROBE CONTROL, filed concurrently herewith and assigned to a common assignee.

The scan head of the invention comprises a plurality of juxtaposed scanning elements formed of a resilient material, each element including a projecting sensor tip. The sensor tips of the plural elements are preferably aligned with one another transversely to the direction of scan of the embossed characters. The sensor tips are sufficiently small so as to effectively trace or scan over the segments or "sticks" of the characters which lie in the corresponding scan paths of the sensor elements.

The scanning elements are mounted between a pair of parallel side walls which extend downwardly so as to define a channel therebetween corresponding to the height of the embossed characters. Suitable drive means, such as a pinch roller drive, is provided for transporting the card past the scanning elements of the scan head. The side walls engage the upper and lower extremes of the raised segments of the characters, and thus guide the line of characters through the channel, and correspondingly define the scan paths of the scanning elements. Preferably, the scan head is received within a housing and resiliently mounted therein to bear against the surface of a card transported therethrough.

The technique of utilizing the side walls to guide the characters of the card through the scan path is of great significance, in that it enables reading of any desired line of characters on a card regardless of the position of that line relatively to the upper and lower edges of the card. This is important, since different commercial credit cards have the characters thereon in different height positions with respect to the upper and lower edges of the card. Furthermore, certain cards themselves are of differing heights. Thus, apparatus which controls the scan path position of a card by guiding on the upper and lower edges requires adjustment means for positioning the card in accordance with the location of the line of characters that are to be scanned. The card positioning technique of the present invention thus eliminates the requirement for any such adjustable card positioning mechanism.

Various alternative embodiments are disclosed herein of the electromechanical transducing portion of the scan head. In one embodiment, the elements carry about the periphery thereof a conducting medium, the elements being normally resiliently biased to engage a support bar also carrying a conducting medium and thereby complete an electrical circuit therebetween in their normal, or undeflected, position. The elements, when deflected in accordance with scanning of character segments in their corresponding scan paths, thus break that electrical circuit and accordingly provide an electrical output signal. An alternative embodiment is afforded by an optical detection system comprising a light source and a plurality of photocells defining a plurality of individual light paths corresponding to each of the elements. The light path is normally maintained to each photocell; upon deflection of the associated element engaging a character segment in its scan path, however, the light path is interrupted and accordingly an electrical output signal is obtained. In either of the electrical-mechanical switching or optical embodiments, the normally closed electrical condition may be reversed to a normally open condition, whereby an electrical circuit or optical path is completed only when the element is deflected in response to sensing of the character segment in its scan path.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of the scan head of the invention with a side portion thereof broken away to reveal the internal portions of the mechanism;

FIG. 2 is an end view of the structure of FIG. 1;

FIG. 3 is a cross-sectional view of the structure of FIG. 1 taken along the line 3--3 of FIG. 1 and further disclosing additional portions of the scan head not shown in FIG. 1;

FIG. 4 is a partial cross-sectional view of the scan head of the invention taken along the line 4--4 of FIG. 1;

FIG. 5 is a perspective view of a single scanning element of the scan head of the invention in accordance with the embodiment thereof shown in FIG. 1;

FIg. 6 is a perspective view of a single scanning element of the scan head of the invention in accordance with an alternative embodiment thereof;

FIG. 7 is a perspective view of a plurality of scanning elements of the scan head of the invention in accordance with a further alternative embodiment thereof and particularly utilizing an optical transducer for producing electrical output signals;

FIG. 8 is a perspective view of a plurality of scanning elements of the scan head of the invention in accordance with yet a further alternative embodiment thereof and particularly utilizing an optical transducer for producing electrical output signals;

FIG. 9 is a representation of characters to be scanned by a scan head in accordance with the invention, and includes a representation of the scan line or scan positions of the plurality of scanning elements of the scan head of the invention;

FIG. 10 is a diagrammatic representation of the output signals produced by the scanning elements of the scan head of the invention when employed to scan the characters represented in FIG. 9, the heavy lines defining the portions of the character segments lying in the scan paths of the scanning elements and effectively the output signals produced by the scanning elements in scanning those segments; and

FIG. 11 comprises a table indicating, for each of the characters of FIG. 9 and the sensing element output conditions derived therefrom as presented in FIG. 10, the sensor conditions resultant from the scanning of those characters assuming the scanning of each thereof to proceed from left to right or, alternatively, the characters to be moved from right to left while the scan head is maintained in a stationary position.

DETAILED DESCRIPTION OF THE INVENTION

The electromechanical scan head of the invention is disclosed herein in a specific embodiment utilized for scanning raised or embossed characters of conventional credit cards. It is to be understood that the scan head may be utilized for scanning any such raised characters for the purpose of producing electrical output signals suitable for processing for automatic character recognition. The specific format or font style of the characters is thus not critical to the utilization of the scan head, although certain basic characteristics are assumed to exist in the characters being scanned as later defined herein.

In FIG. 1 is shown a side elevational view of the scan head of the invention with a side portion thereof broken away to facilitate the illustration and discussion of the internal operating mechanisms. FIG. 2 comprises an end view of the scan head substantially as shown in FIG. 1. FIG. 3 comprises a cross-sectional view of the scan head taken along the line 3--3 in FIG. 1, and further showing a housing and support structure for the scan head and a drive or transport mechanism for transporting credit cards past the scan head for scanning of the raised characters. Reference will be had hereinafter simultaneously to the views of FIGS. 1, 2 and 3.

The scan head 10 includes a pair of spaced side walls 12 and 14, preferably joined at the top by a horizontal top wall 16 secured thereto by suitable means (not shown). A plurality of scanning elements A through E, best seen in FIG. 3, are received in juxtaposed relationship between the walls 12 and 14 and are spaced from one another by low friction, non-conductive spacer or separating sheets 18. In FIG. 1, the side wall 12 has been broken away to reveal a portion of the last scanning element E and the associated sheet 18 which spaces that element E from the adjacent element D. The elements A through E and the associated separating sheets 18 are positioned together in a sandwich-type structure between the walls 12 and 14 and are secured at one end of the scan head 10 by conventional securing means such as screws and nuts 20. Whereas the separating sheets 18 extend the full length of the scan head 10 to be secured at the opposite ends thereof, the elements A through E necessarily are foreshortened for freedom of movement of one end thereof. Thus, to maintain proper spacing of the walls 12 and 14 to permit freedom of movement of the elements A through E, spacer elements 22 of a width corresponding to that of the sensing elements A through E are positioned intermediate the sheets 18 at the other end of the head, as best seen in FIG. 2 and the structure secured to conventional securing means 24. Further, to assure freedom of movement of the elements A through E, an additional pair of spacer elements 18a is provided between the side walls 12 and 14 and the respectively next adjacent spacer elements 22 and a similar pair of spacer elements 18b between those same side walls and the next adjacent elements A and E. The elements 18a and 18b are of generally the same height as the spacer elements 18 but are only of a length sufficient to be secured by the securing means 20 and 24. Thus, as these securing means 20 and 24 are tightened, the elements A through E nevertheless have adequate freedom of movement. The top wall 16 is then secured to the side walls 12 and 14 by any suitable means (not illustrated).

The side walls 12 and 14 include downwardly protruding flanges 13 and 15, respectively, defining therebetween a channel of a width corresponding to the height of the characters to be scanned. In general, the characters to be scanned are assumed to be arranged in a line and to be carried by, or formed in, a medium such as a credit card, as illustrated at 26 in FIGS. 1 and 3. For example, in FIG. 1, there is shown a card 26 carrying upwardly protruding, embossed characters, as illustrated at 27 through 31.

As will be appreciated, and as detailed in the following discussion of operation, the space between the flanges 13 and 15 is to correspond to the height of a character. Accordingly, the thickness of the spacer elements as above described, as well as of the scanning elements, is selected accordingly. For example, characters of the 7B font typically employed in credit cards are approximately 0.170 inches to 0.180 inches in height. Thus, the scanning elements A through E may each be of 30 mils thickness, the spacer elements 18 of 5 mils thickness, and the spacer elements 18a and 18b of 5 mils thickness. The total thereof affords a spacing between the side walls of 0.180 inches. Further, this spacing assures accurate alignment of the scanning elements with the character segments intended to be scanned thereby.

With reference to FIG. 4, taken along the line 4--4 of FIG. 1, the card 26 is shown at an intermediate position in its transport path through, or past, the scan head 10, the card having advanced beyond the initial point of entry as shown in FIG. 1. The representative characters 27, 28, . . . on the card 26 as identified in FIG. 1 are shown in FIG. 4 specifically as the numerals 2, 9, . . . . It is assumed that the characters to be recognized are of a uniform height, or that at least most of the characters are of a uniform height, which height corresponds to the width of the channel defined between the flanges 13 and 15 of the walls 12 and 14. Accordingly, those flanges engage the upper and lower extremes of the characters and thereby automatically align the line of characters, i.e., the data line, for scanning by the scan head as the card is transported therethrough. It will be appreciated that the side walls 12 and 14 must provide adequate structural support for the head 10. Thus, the flanges 13 and 15 may simply comprise an integral portion of those side walls, and which are formed by undercutting of the side walls. The thinner flanges 13 and 15 thus afford some limited flexibility, or give, in effecting alignment of the line of characters, and also assure that they may be received between closely adjacent lines of embossed characters on a card.

The transport or drive means is shown only diagrammatically, and is best illustrated in FIG. 3. The card 26 is received on a support surface, or bed, 34 having openings 36 and 38 therein through which extend a pair of drive rollers 40 and 42, respectively. The drive rollers 40 and 42 are affixed to a common drive shaft 44 carrying a gear 46 engaged in turn by a gear 48 of a drive train connected to a prime mover for driving the rollers 40 and 42 in rotation at a desired speed. Pinch rollers 50 and 52 are aligned with the drive rollers 40 and 42 to engage the card 26 therebetween at the upper and lower longitudinal edge portions thereof and thereby to transport the card past the scan head, the line of characters to be scanned being received in the channel defined by the flanges 13 and 15 of the side walls 12 and 14.

The pinch rollers 50 and 52 are suitably supported, as diagrammatically illustrated by the associated drive shafts 51 and 53 connected to adjustable brackets 54 and 56, respectively.

As will be apparent, various modifications in the spacer transport mechanism may be made. Although for simplicity, only one set of drive and pinch roller pairs is afforded in a longitudinal direction, two or more such sets could be employed, the function, of course, being to assure transport of the card past the scanning head but as well to afford convenience in the inserting and withdrawing of the card therefrom. It may also be desirable to employ opposing pairs of drive rollers rather than a pair of drive and pinch rollers, as shown, to afford more positive transport drive control.

The scan head 10 and the transport mechanism, and particularly the pinch rollers 50 and 52, are received with a housing 60 which is secured to the support base 34. Conveniently, the brackets 54 and 56 may be mounted to the vertical side walls of the housing by securing means, generally shown as the screws 62 and 64, respectively, which are received through elongated slots in those side walls to permit height adjustment of the pinch rollers 50 and 52. It will, of course, be appreciated that any suitable mounting and adjustment means may be provided to permit developing the desired amount of force of engagement of the drive wheels 40 and 42 and the associated pinch rollers 50 and 52 to provide adequate engagement of each card 26 for feeding, or transporting, thereof past the scan head.

It will be noted from FIG. 3 that the support base 34 is of a width substantially in excess of the height of the card 26, i.e., the transverse dimension of the card with respect to the line of characters to be scanned. This permits displacing of the card, as required, to align the line of characters to be read for entry into the channel defined by the flanges 13 and 15. Thus, the location of the line or lines of characters of a card to be read presents no alignment problems in inserting a card into the scan head for reading.

Preferably, the scan head is resiliently biased into engagement with the card, thereby to afford automatic compensation for thickness variations of various cards to be scanned. Accordingly, housing 60 is shown to include a pair of downwardly extending, elongated flanges 66 for receiving the scan head 10 therebetween and in sliding engagement therewith. The flanges 66 restrict the movement of the head to a limited extent of vertical reciprocatory movement within the housing 60. Resilient biasing means, such as springs 68, urge the head 10 downwardly toward the support base 35 and therefore into engagement with a card 26 received on the support 34.

As previously noted, the head 10 includes a plurality of sensing elements, or sensors, defining a corresponding plurality of scan paths utilized in scanning each character of a line of characters. In general, the elements include a scanning tip, or wiper, as shown at e for the element E in FIG. 1, and at a through e for elements A through E as shown in FIG. 3. These tips or wipers are preferably in alignment, forming a linear array thereof, extending transversely of the direction of scan of the line of characters. For convenience of description only, the direction of scan may be characterized as horizontal, and thus the aligned tips or wipers of the scanning elements extend traversely of the horizontal scan direction, defining parallel scan paths. Further, the elements are typically evenly displaced so as to define evenly displaced scan paths. The particular location and number of the scan paths is, however, a function of the font style of the characters to be scanned, as later described.

In FIG. 5 is shown a single one of the scanning elements A through E in accordance with the specific embodiment thereof illustrated in FIG. 1. Each of the elements in this embodiment is identical in structure, and includes a resilient arm carrying electrical conducting material and arranged to selectively engage a contact structure so as to effect an electrical switching function. The arm includes an enlarged end portion 70 having apertures 72 therein for receiving the securing means 20 as shown in FIG. 1, an elongated shank portion 74, a scanning tip or wiper 76, corresponding to the tips a - e as referenced in FIGS. 1 and 3, and a switch contact portion 78.

A thin wire 80 is affixed to the arm, the wire extending along the lower horizontal, the vertical, the upper horizontal, and the rear vertical edge surfaces of the switch contact portion 78 as well as along the shank 72 and the enlarged end portion 70. The wire 80 is secured thereto by a suitable adhesive, such as an epoxy. It will be appreciated that the wire diameter is the same as, or slightly less than, the thickness of the element. The rear edge of the end portion 70 also has affixed thereto, such as by an epoxy, a conductor strip 82 to which the wire 80 is mechanically and electrically connected as by soldering. Finally, an external lead 84 is mechanically and electrically secured to the strip 82. With reference to FIG. 1, and as shown there in diagrammatic form, the leads 80 to the plurality of elements A through E are preferably vertically displaced to facilitate the assembly of the sandwich structure of the scan head 10.

The other contact portion of the switch for each element is provided by a small diameter, metallic rod 86 which also serves to define the vertical position of each element. With reference to FIGS. 1 and 3, the rod 86 supports each of the elements A through E by engaging the lower surface of the contact portion 78 of each thereof in the normal or rest condition, each element being slightly urged upwardly in that rest condition so as to be resiliently urged into contact with the rod 86. In the rest condition, therefore, the rod 86 provides a common electrical connection to the wire 80 secured to each element, and particularly at the lower horizontal surface of the contact portion 78 of each element.

The resilient arm of the contact element may be made of any suitable resilient material, particularly including various plastics, which are of sufficient abrasion resistance to enable long use thereof for the disclosed scanning or wiping function which the scanning elements perform, as well as capable of withstanding the stresses imposed by the deflection thereof. As specific examples, the material utilized in conventional credit cards has been found to be quite acceptable; in addition, Lexan may be used. Lexan or other of the noted materials may also be used for the side walls of the scan head. The side walls, however, must be of substantially greater rigidity and therefore will normally be of greater thickness than the scanning elements. The spacing sheets 18 are formed of any suitable low friction, relatively durable material; further, they preferably are of an electrical insulating material. A very thin sheet, such as 5 mils in thickness, of Mylar is suitable for this purpose.

As an alternative, the flexible arm may itself be made of metal. In that case, no further electrical conductor need be provided thereon, but rather an external output lead may be connected directly to the arm, the arm itself completing the circuit to the common bar 86.

As illustrated in FIG. 3, when portions of character segments are received beneath the scanning elements, those elements are deflected or raised upwardly, thereby breaking the connection between the wire 80 and the common electrical contact and mechanical support rod 86. Particularly, the elements A and B are shown to be so raised by portions of a character segment lying in their respective scan paths. Conversely, elements C, D and E remain in contact with the rod 86, the scanning tips thereof being slightly above the background or surface level of the card 26.

Accordingly, it will be understood that the wire 80 and the common rod 86 afford a normally closed switch which is opened upon the scanning tip 76 of any element engaging a character segment in its scan path. The opening and closing of the switches as thus defined between the contact portion of each switching element and the common rod 86 afford a plurality of electrical output signals corresponding to the mechanical scanning function of the array of scanning elements.

Before considering further the characteristics of the electrical output signals, there will first be discussed alternative embodiments of the switching elements. In FIG. 6 is shown an alternative embodiment of an electromechanical switching arm similar to that of FIG. 5. In FIG. 6, the resilient arm is identical to that of FIG. 5 and thus corresponding portions thereof are identified by the identical reference numerals 70, 72, 74, 76 and 78. In FIG. 6, a conductor 90 is plated along the periphery of the contact portion 78 including its upper and lower horizontal surfaces and the front and rear vertical surfaces thereof, along the upper surface of the shank portion 74 and along the vertical front surface of the enlarged end portion 70. That conducting material is further made continuous or integral with a plated surface 92 along the upper planar surface of one side of the end portion 70 and a vertical strip 94 adjacent the rear edge of that same planar surface of the end portion 70. An external lead 96 is then mechanically and electrically secured to the strip 94 which thus serves as a connector strip for the external connection. Again, the external leads 96 are preferably vertically displaced for the plurality of elements to facilitate the assembly of the sandwich construction.

In FIGS. 7 and 8 are shown further embodiments of the switching elements wherein the transducing function for deriving electrical output signals corresponding to the mechanical switching operation is afforded by an optical coupling arrangement employing a light source and photocell detectors. The basic configuration of the resilient arms of the switching elements is substantially identical to that of the electromechanical elements of FIGS. 5 and 6 and thus are identified in FIG. 7 by identical but primed numerals and in FIG. 6 by identical but doubly primed numerals.

In the embodiment of FIG. 7, the portions 78' of the elements A through E further include upwardly projecting tabs 100, 101, 102, 103 and 104 at successive longitudinally displaced locations. A light source 105 and a photosensitive detector 106, the latter including a number of individually operable photosensitive devices, cooperate to define a number of independent light paths corresponding to the number of scanning elements. In the specific embodiment disclosed, five independent scanning elements A through E are employed and thus five light paths are defined by the optical system 105, 106. Further, the light paths are aligned with the respectively associated tabs 100 through 104 but are located vertically thereof so as to be normally completed between the source 105 and the sensors 106. When an element engages a character segment, it is raised upwardly and its associated tab intercepts the normally maintained beam of light, rendering the associated photocell dark and affording an electrical output signal. This effect is illustrated in FIG. 7 by the first scanning element A being raised or deflected upwardly to correspondingly project its tab 100 into the associated light beam path.

In FIG. 8, the portions 78" of elements A through E include apertures 110 through 114, respectively, aligned with corresponding light beam paths defined as a source 105' and a plurality of sensors 106'. In addition, each of the successive elements B through E includes notches 115 and 118 therein positioned in alignment with the apertures of the other elements. For example, the element E includes in its portion 78" notches 115 through 118 corresponding to the apertures 110 through 113. The notches, as thus illustrated for the element E, are of a length such that when the element E is raised upwardly, the light path is maintained for each of the preceding elements, i.e., it is not interrupted by the portion 78" of the element E, even when raised vertically. Conversely, the raising upwardly of the element E does serve to block its associated light path normally maintained through aperture 114. The selective blocking effect is readily visualized in the raising of any one or more elements for achieving the same result as shown in FIG. 7, and thus is not illustrated in FIG. 8.

Inasmuch as the remainder of the housing and scan head utilized with the scanning elements of FIGS. 7 and 8 may be identical to that previously described, only those elements and the associated optical transducing units are shown therein. For example, it is to be understood that a spacing sheet may again be provided between the adjacent elements, the function in this instance being merely to facilitate the independent raising and lowering of each element and not for electrical isolation of adjacent elements. Similarly, a mechanical support, such as rod 86", is provided for vertical alignment and positioning of the elements.

By way of illustration only, there is shown in FIG. 9 a representation of characters to be scanned by the scanning head of the invention, and a schematic representation of the scan path or scan positions A' through E' for the plurality of scanning elements A through E of the scan head. The font style of the characters is the well-known Farrington 7B font, frequently used in conjunction with automated data processing equipment. In FIG. 10 is provided a diagrammatic representation of the mechanical actuation of the scanning elements and thus also of the electrical output signals produced by those elements in scanning the corresponding characters of FIG. 9. Similarly, the scan paths or scan positions of the plurality of scanning elements A through E are identified in FIG. 10 at A' through E'.

Characters in the Farrington 7B font style are formed of various combinations of seven basic character segments, or sticks. These characters are essentially of the match stick variety and are comprised of essentially seven straight line portions or match sticks. These seven portions comprise upper, lower, and middle horizontal sticks, upper and lower left, and upper and lower right vertical sticks. In general, reference to the numeral, or character, 8 illustrates the totality of the seven line segment font. For ease of visual recognition, however, various contouring effects are presented in the character configuration for closer resemblance to conventional characters. For example, the corners are rounded a bit and a "waist" is provided at the junction of the vertical segments and both ends of the horizontal segment of the numeral 8. Other similar modifications are apparent in the other numerals. Notably, 1 has a small flag extending to the left, as to the numeral 3, the horizontal bar is foreshortened and a "waist" effect and rounding of corners provided, and as to the numeral 4, the continuous vertical line formed by the upper and lower right vertical segments is shifted to the left for more conventional appearance and to assist in distinguishing a 4 from a 9, for example.

From FIGS. 9 and 10, it will be appreciated that the scanning tips, or wipers a through e of the elements A through E are selected as to the number and location thereof in accordance with such a font style. Particularly, the tips a, c and e are in alignment with the upper, middle, and lower horizontal sticks, respectively, and the tips b and d are intermediately positioned so as not to scan those horizontal sticks but only the upper and lower vertical sticks, of both the left and right sides of the characters.

As previously noted, the scan of the characters is effected by relative movement of the line of characters and the scan head. As particularly disclosed herein, the scan head is held stationary while the carrier for the embossed characters, particularly a credit card, is moved relatively to the scanning head. Furthermore, the scanning is illustrated herein for a structure in which the line of characters as shown in FIG. 9 is moved to the left relatively to the scan head, and thus in accordance with a conventional left to right direction of visual reading of a line of characters.

Regardless of the direction of reading, however, it will be appreciated that a time-distance function obtains in the reading of characters as they are scanned by the read head of the invention. Thus, the elements are variously and independently deflected as they engage the raised character segments in their respective scan paths, correspondingly producing electrical output signals representative of that scanning operation by virtue of the independent switching functions of the plural elements.

In general, the alignment of the scanning tips assures that substantially simultaneous signals are produced by any two or more scanning elements initially engaging character segments in their respective scan paths. The above-noted styling of the characters for aesthetic appeal as well as the variations in configuration and location, e.g., skew, to introduce some variations causing departures from the ideal simultaneous switching operations. However, the finite width of the character segments is generally sufficient to assure that for some intervals of time during the scan, simultaneous signals will obtain, i.e., even as to scanning of a vertical segment by any two or more scanning elements.

In FIG. 11 is provided a table illustrating the sets of conditions of the scanning elements, as to their being raised or deflected upwardly upon engaging character segments in their corresponding scan paths, which result in the scanning of each of the characters of FIG. 9 in accordance with the direction of scan from left to right as discussed above. In the table of FIG. 11, the letters A through E are utilized in a Boolean algebra representation to indicate the scanning of a segment of the character in the scan path of the elements A through E, and the letters A through E indicate the absence of sensing of any character segment by the corresponding scanning elements, and thus that the scanning elements remain in their normal or rest position.

The previously noted copending applications of Raymond J. Deschenes entitled CHARACTER RECOGNITION METHOD AND SYSTEM and of John A. Cribbs et al. entitled CHARACTER RECOGNITION METHOD AND SYSTEM WITH STROBE CONTROL set forth methods and systems for processing the electrical output signals of the scan head of the present invention in accordance with achieving automatic character recognition. The sets of conditions thus defined in FIG. 11 are directly resultant from the scanning operation of the scan head, of course, but are of significance in a logic sense for the successful recognition of characters in accordance with the methods and systems as therein set forth.

The sets of conditions which obtain in scanning each of the characters 1-9 and 0 is thus set forth in the first table of FIG. 11 and may be compared directly with the scan indications in FIG. 10. It is important to note that the sets of conditions occur in a sequence uniquely related to and directly defined by the configuration of each character. That is, each set of conditions is established as a direct result of the scanning operation. Further, a new set is defined when the condition of any one or more of the scanning elements A' through E' changes.

For example, the numeral 1 defines three sets of conditions. The first set, A B C D E is that of the condition that E alone is true, i.e., the scanning element E', and no other scanning element, has detected a segment of the unknown character, with reference to FIGS. 1 and 2, that segment comprises the lower horizontal bar of the numeral 1. When the flag portion of the top of the numeral 1 is detected by the element A', a new set of conditions A B C D E obtains. Similarly, when the vertical bar is detected by elements B', C' and D' -- which occurs simultaneously with the continuation of the sensing condition for elements A' and E' -- the set A B C D E obtains. Finally, only the condition E remains true after passing beyond the vertical line segments of the 1 and thus a further, and here, final set A B C D E is defined.

Note particularly that the various sets of conditions are independent of the time duration of these conditions as actually experienced during scanning, and further that the recognition of these various sets relates entirely to the actual scanning of the configuration of the character and is not imposed by any arbitrary timing function. Further, assuming the same general relationship of the segments of each character, these identical states will obtain regardless of width variations, whether of a random or uniform nature with respect to the individual characters of the set.

A further set of conditions is also included in FIG. 11, corresponding to the absence of sensing of any portion of any character and thus to the location of the sensing elements preceding or following any character and intermediate any two characters. This is termed a space to distinguish from the character conditions, and corresponds to the condition A B C D E. The space is processed by logic decoding means to define the state U. The state U is utilized for various purposes, for example, for identifying the completion of scanning of a character.

An analysis of the successive sets of conditions in FIG. 11 will reveal the fact that a unique sequence thereof exists for each of the characters indicated. Further, when no character is being detected, the space condition A B C D E will obtain, enabling automatic recognition that the scan head is currently scanning a portion of the card preceding or following the line of characters or intermediate successive characters.

As more fully developed in the cited copending applications, substantial redundancy exists in the sets of conditions obtained in scanning of the characters provided in the illustrative table of FIG. 11 and thus fewer than all of the available sets may be employed for logic processing in the automatic recognition of the characters.

It is also to be appreciated that the scan head of the invention may be utilized with methods and systems other than those of the cited copending applications. Particularly, rather than utilizing the successive sets of conditions as provided for in the methods and systems of those applications, the electrical output signals produced by the scan head of the invention may instead be utilized in accordance with the time duration of the output signal representing scanning of a character segment independently of, or in relation to, the time duration of the output signals of the other scanning elements, and thereby afford a basis for character recognition. Other methods and systems suitable for utilizing the output signals provided by the scan head of the invention will be readily apparent to those skilled in the art.

It is also to be understood that the specific number and configuration of the scanning elements is not to be considered limiting. It is important, however, that sufficient resiliency be afforded in any such element to achieve the deflection thereof as described, and to assure that the scanning tip of each element is sufficiently small as to accurately and reliably scan a character segment in the scan path thereof to thereby effect the electrical switching operation for producing the electrical output signal.

Numerous modifications and adaptations of the invention will be apparent to those skilled in the art and thus it is intended by the appended claims to cover all such modifications and adaptations thus falling within the true spirit and scope of the invention.