Matches 451 - 500 out of 543 < 1 2 3 4 5 6 7 8 9 10 11 >
Match Document Document Title
4993011 Optical recording apparatus with simultaneous erasing and recording  
An erasing beam B1 and a recording beam B2 emitted from a laser diode array 20 are focused on different tracks of a optical magnetic disk D, the erasing beam B1 being focused on a track located...
4987301 Reflective optical encoder device with light beams applied as spats spaced by 2 predetermined pitch  
A reflective rotary optical encoder device for detecting an angular speed or position of a movable member includes an optical encoder disc rotatable with the movable member, the optical encoder...
4982395 Composite optical grating for optical disk data storage systems  
The composite optical grating for optical disk data storage systems uses a first optical grating to generate three light beams disposed approximately on a straight line. A second optical grating in...
4972396 Multiple independently positionable recording-reading head disk system  
A multiple independently positionable recording-reading head optical disk system. The system includes at least one optical disk having an arrangement of data elements. A plurality of...
4965781 Data reading device having servo controlled position reset  
In a data reading device of the type in which a servo loop controls the movement of a reflection mirror to control the position of the data detection point, a second servo loop is used to return...
4949331 Apparatus and record carrier for optical disc memory with correction pattern and master disc cutting apparatus  
A record carrier having a disc-shaped substrate and a recording layer for optically writing information therein is disclosed which includes a guide groove extended in the rotational direction of...
4935911 Optical head device for recording and reproducing information  
An optical head device for recording and reproducing information includes beam splitting and converging mechanisms which has a first portion and a second portion secured to the first portion and is...
4929822 Detection system with an optical encoder to optically detect displacement amount of a movable device  
An optical detection system for detecting a displacement amount of a movement device with an optical encoder movable in accordance with a movement of the movable device has on a light-reflecting...
4929823 Optical pickup head with holographic servo signal detection using a spot size detection system  
An optical pickup head apparatus comprises a hologram element disposed in the flux of light reflected back from an optical disc, and first and second photodetectors respectively having linear...
4918300 Optical pickup system having multiple diffraction devices and lens holding means  
An optical pickup device for reading signal pits on a disk includes a light source, first and second diffraction devices, a first holding member for holding a photosensor and a hollow second...
4890272 Apparatus for correcting photodetector signals in a system for retrieving information from an optical recording medium  
A system capable of retrieving, recording or erasing information from an optical recording medium such as an optical disk or card. Two or more light beams reflected from the optical memory are...
4888755 Optical head for recording informations into a record medium and reproducing the same therefrom  
An improved optical head comprises such a means as a prism for separating a plurality of light beams deflected from the light path between a plurality of light sources and record medium to pass at...
4875203 Tracking servo signal generating device for an optical disc  
An optical disk reproducing apparatus of the type in which a tracking control is performed by projecting a controlling laser beam to the center of each of a plurality of V grooves formed on an...
4864326 Dual beam recorder  
A recorder has a beam generator for generating a beam to form a dot image on a record medium. The beam generator has first and second beam generation sources to generate first and second beams and...
4855986 Data storage and readout optical head using a single substrate having an electrooptic converging portion for adjustment of the light beam focal point  
An optical head for optical storage and readout of information on or from an optical recording medium using a light beam comprises a single substrate having a waveguide on one of its opposite...
4855987 Optical device comprising a holder accommodating an optical system which compensates for thermal expansion/contraction  
An optical system is described, for example a radiation source unit (10) supplying a collimated radiation beam (RB), comprising a tubular holder (30) a radiation source (33) arranged in the holder...
4853919 Information processing apparatus in which a deflected light and O-order light are respectively used for information recording/reproduction and tracking, and a method therefor  
This specification discloses an information processing method and apparatus in which light deflected by diffraction is caused to arrive at the surface of a recording medium and when recording or...
4843494 Data storage apparatus using optical servo tracks  
A magnetic data storage system for use with a double sided disk in which a prerecorded pattern of opaque optical lines is used to define the tracks in which magnetic data is to be stored. A...
4841508 Method and apparatus for detecting a track and focus errors in an optical head  
A method and apparatus for detecting a track and focus errors in an optical head comprises a step of dividing light beam which is reflected from a recording medium into at least a first, second,...
4841514 Optical recording method and apparatus using two fight spots  
A light spot determining a first condition that an optical recording medium is cooled after being heated to a temperature exceeding a first temperature and a light spot determining a second...
4841507 Optical head for an optical recording and reproducing apparatus  
An optical head for optical recording and reproducing system comprising a light source, a first optical means for introducing a light beam from the light source into a guide groove formed in a...
4831609 Tracking method and apparatus for optical recording medium  
A tracking method for reading/writing data with respect to an optical recording medium having clock tracks each formed of clock bits of optical patterns and data tracks. The method is carried out...
4825064 Apparatus for energizing a semiconductor laser array having a plurality of light beam emitting points  
In an apparatus for energizing a semiconductor laser array, the semiconductor laser array has first and second laser structures. The first laser beam emitted from the first laser structure is...
4817072 Optical head utilizing diffraction grating  
In an optical type head device comprising a light source for emitting a light beam, a beam splitter, a condensor lens and a light detector for receiving said light beam for photoelectric conversion...
4817074 Method and apparatus for detecting the focusing state and positioning accuracy of a light beam directed onto an optical disk tracking guide in an optical recording system  
In method and apparatus of detecting tracking and focusing errors in an optical recording system, such means for dividing light beam reflected from an optical recording medium into four light beams...
4804835 Optical head having guide means with first and second polarizing surfaces  
In an optical head, a laser beam emitted from a semiconductor laser is collimatted by a convex lens and is reflected by a polarizing surface of a prism. The reflected laser beam passing through a...
4787076 Optical disc tracking system with switching of tracking error signals at boundary between track guide and track address  
A tracking system for positioning a light spot onto a magneto-optic disc having a beam guide track preformatted thereon, includes a main light beam and two auxiliary light beams, and a circuit for...
4785438 Magneto-optical disc reproducing apparatus with improved two-part head  
A reproducing apparatus for magneto-optical discs has a moving head portion and a fixed head portion. Light reflected from the disc is divided into two parallel light beam components having...
4775968 Tracking error detecting system for optical head  
According to a tracking error system of an optical head of the present invention, a pair of beams are irradiated through an objective lens (4) on an optical record medium (5) with a distance of a...
4769806 Disc information reproducing apparatus  
A disc information reproducing apparatus for reproducing information stored on an optical recording medium, the apparatus being subjected to expose to environments of varying temperature which...
4768183 Optical reproducing apparatus  
Light beam emitted from a laser light source is focused by an objective lens and applied in this state to an optical information recording medium. In the optical path between the laser light source...
4759007 Storage medium track pitch detector  
Method and apparatus for measuring the spacing between adjacent information tracks on a recording medium. A spot of light is projected onto at least a portion of a first track and maintained in a...
4753513 Optical type head device  
An optical type head device comprises an optical beam separating means having a first surface which functions to reflect a principal light beam emitted from a light source and to separate it into a...
4754129 Grating adjustment apparatus of 3-beam type optical pick-up  
This invention relates to a grating adjustment apparatus of 3-beam type optical pick-up for the compact disk player and, more particularly, to an apparatus automatically and readily adjusting a...
4750162 Optical tracking system utilizing three photo-detectors  
In apparatus for optically reproducing information recorded on an optical recording medium, an optical pickup device is arranged such that three light beams obtained by a diffraction grating are...
4744071 Optical head in a device for recording and reading a data carrier  
The optical head in the recording-reading device of a data carrier comprises a semiconductor laser source. A lens makes it possible to focus the beam from this source on to the data carrier via a...
4727528 Optical media tracking method and apparatus for optical storage system  
An optical data read/write apparatus is disclosed for use in reading a rotating optical disc having at least one concentric reference track and circular data tracks thereon. The apparatus includes...
4727381 Appartus for, and methods of, inscribing patterns on semiconductor wafers  
An energy (i.e. laser) beam directed to a photoresist layer is scanned in a first direction through lines progressively displaced in a second coordinate direction. In this way, stripe areas of a...
4722079 Optical disk player capable of distinguishing external disturbances and local defects and adjusting servo gain accordingly  
In a three-beam type optical data disk player, beam output disturbances due to an external disturbance such as vibration and the beam output disturbances due to a local defect on the disk are...
4720825 Optical data reproducing devices having improved trick play capability  
An optical data reproducing device including an illuminating system for respectively, simultaneously illuminating at least two separate tracks of an optical disk with at least two light beams; a...
4712206 Tracking error signal detecting device with a two-beam system for use in an optical information memory  
A tracking error signal is detected by irradiating an information pattern recorded on an information carrying member with first and second light beams, the second light beam being incident on the...
4686663 Track follower system employing an optical scanner with automatic control of a rotatably movable phase grating used for the generation and positioning of read beam spots  
A radially acting track follower system is provided with an optical scanner pickup for an audio or video record playback apparatus. The system generates three light spots disposed on a line with a...
4682314 Disc playback apparatus  
In a disc playback apparatus using an optical pickup or the like, any flaws on a track of the disc are detected using: a first level detector for detecting a maximum value level of a recording...
4674070 Optical type disc with V-shaped groove and optical type reproducing apparatus therefor  
An optical type disc is recorded with information signals on each sloping surface of a spiral or concentric V-shaped grooves formed on a recording surface thereof, wherein the information signals...
4669070 Signal format for optical tape record/playback system  
An optical tape record/playback apparatus is provided for recording/reproducing information signals onto an optical tape. The record apparatus comprises laser sources which are modulated in...
4669071 Photo sensor device and optical pickup device  
A photosensor device and an optical pickup device incorporating the photosensor device are advantageously used in an optical compact disc player of the type where the optical pickup device is...
4660191 Tracking signal error generator for optical information devices  
A tracking error signal generator includes first, second, and third light receptors for receiving light fluxes reflected from a recording medium and for generating respective first, second, and...
4658389 Track follower system for correcting tangent errors in an optical record scanning system  
A radially acting track follower system with an optical scanner for an audio or video record disc playback apparatus is provided. The apparatus generates three light spots disposed approximately on...
4644160 System for holding plural light beams in predetermined relative positions  
Herein disclosed is a system using a plurality of laser beams, in which the positions of the respective laser beams are detected as the differences between the outputs of detectors of an optical...
4633455 Headwheel for a multiple beam optical tape playback system  
A multiple track playback headwheel is disclosed for use in a helical scan optical tape recording system. The headwheel includes optical diffraction gratings at the center of rotation of the...
Matches 451 - 500 out of 543 < 1 2 3 4 5 6 7 8 9 10 11 >