Abstract: A method of optically reproducing information from an optical recording medium on which concave or convex signal pits are formed, is provided with the steps of: irradiating each of pit edge portions of one signal pit which are opposed to each other, with a reading light respectively; detecting a reflection light from each of pit edge portions, separately, to output two detection signals indicating detected positions of the pit edge portions with respect to one signal pit; and reproducing one information recorded in one signal pit on the basis of the two detection signals.

Abstract: An optical data transmission apparatus includes a hole-burning effect element for recording data. Upon transmitting input serial data in a multiplex mode along a single optical fiber, the input serial data are stored in the hole-burning effect element having an inhomogeneous broadening on the light absorption spectrum, and then light transmitted through the hole-burning effect element is transmitted over the optical fiber. At the receiver end, the laser light is divided into a plurality of portions having different wavelengths and these portions are made incident upon a light receiving element array.

Abstract: An optical recording medium comprises a transparent substrate, an inner protection layer, a recording material layer, an outer protection layer, and a reflection layer, which are laminated in this order. In an in-groove recording mode, the ratio of the thickness of the recording material layer to the thickness of the outer protection layer is in a range between 0.52 and 0.95. In an on-land recording mode, the ratio of the thickness of the recording material layer to the thickness of the outer protection layer is in a range between 0.32 and 0.6.

Abstract: By using a two-beam optical head, simultaneous focusing of two light spots can be achieved and the execution of simultaneous erasure, recording and reproduction of information can be easily realized even in an inexpensive optical system which uses lenses having chromatic aberration. The two-beam optical head includes a monolithic semiconductor laser array having two light-emitting points which emit first and second light beams having different light intensities, and an optical system for forming first and second light spots on a magnetooptical disk. The two light beams pass along substantially the same optical path. The direction of the arrangement of the first and second light-emitting points of said light source unit is inclined with respect to a plane perpendicular to the optical axis of the optical system to focus the light spots on the same plane of the magnetooptical disk.

Abstract: In an optical recording and reproducing method and an apparatus employed for effecting the method, in a light beam of a wavelength .lambda.1 is converted by a laser unit into a light beam having a wavelength .lambda.2 which shorter than the wavelength .lambda.1 through employment of a wavelength converting element, and the light beams with wavelengths .lambda.1 and .lambda.2 are converged at approximately the same spots on a recording medium. For recording a signal, a light intensity of the light beam of the wavelength .lambda.1 projected onto the recording medium is arranged to be a light intensity for not effecting recording of the signal independently, and recording of the signal is effected through modulation of at least the light beam of the wavelength .lambda.2 to be high or low intensity according to the signal to be recorded. For recording or reproducing signals, focus control and tracking control are effected by detecting only the light beam of the wavelength .lambda.

Abstract: A lens/mirror tower (LMT) of a multiple-disk array, optical storage system includes a plurality of lens and mirror elements integrally formed on a monolithic, optically-clear substrate. There is a specific lens/mirror set for each recording disk surface of the optical storage device; however, the mirror elements are preferably configured as one reflective surface of the substrate. The lenses are molded onto the opposite surface in a single operation that fixes their relative positions. The LMT is generally fabricated using a lens replication process. Initially, a glass substrate is formed with a trapezoidal configuration. A lens array mold is also formed with a plurality of cavities arranged in overlapping pairs. The cavities are filled with optical-quality resin and the mold is applied to the surface of the substrate opposing the reflective angular, e.g., 45.degree., surface. Once cured, the resin serves as an array of lenses that are aligned with the optical paths to the objective lenses of the disk array.

Abstract: Light spots are irradiated onto an optical disk and are detected as signals. A selection is made to receive as an input one of the detected signals from the light spots. The use of two light spots in a signal processing system permits writing information with one light spot and then reading it with the other to confirm the write state or erase state of the information.

Abstract: A method for optically reading recorded information by radiating laser light emitted from a semiconductor laser which oscillates in a single longitudinal mode to an information recording medium and by detecting laser light reflected from a recording face of the information recording medium is disclosed. In the method, the optical frequency of the laser light is modulated in order that the modulated optical frequency is a periodic function dependent on time, and the absolute value of a time differential coefficient R (Hz/s) of the periodic function, a spectral line width .delta. .nu. (Hz) of the laser light, and a time period .tau. (s) from the time when the laser light is emitted to the time when the laser light reflected from the recording face of the information recording medium reaches the semiconductor laser satisfy the condition of R.gtoreq..delta. .nu./.tau.. The periodic function varies to have a sawtooth waveform or a triangular waveform.

Abstract: A device for detecting the position of a recording/reproducing element, which is provided with two position detecting elements having the same input/output characteristics and a device for generating a difference signal representing the difference between output signals of the two position detecting elements. Further, the outputs of the position detecting elements vary correspondingly to change in position of the recording/reproducing element in such a manner to be complementary to each other.

Abstract: An apparatus for writing and reading a magneto-optical record carrier (1) with an increased information density are described. Information areas (4) which are smaller than the write spot (V.sub.w) supplied by a first diode laser (40) can be written by a switched magnetic field. The areas can be read with a read spot (V.sub.r) which is smaller than the write spot, which read spot is formed by radiation from, for example an assembly of a second diode laser (42) and a frequency doubler (43).

Abstract: A plural beam optical head is constituted by an optical system for imaging a plurality of light beams onto an optical information recording medium, a double-refractive crystal prism and a sensor. The plurality of light beams obtained from the optical information recording medium are separated into components the polarized direction of which are orthogonal one another by the double-refractive crystal prism. The direction of arrangement of the plurality of light beams incident on the double-refractive crystal prism is substantially perpendicular to the direction of separation of the light beams obtained from the double-refractive crystal prism. The light beams from the double-refractive crystal prism are received by the sensor.

Abstract: A focal point position detector has a light source for emitting light; an optical system for converging light from the light source to an optical recording medium; a coupler for coupling light from the optical recording medium thereto; a waveguide concave mirror for converging light from the coupler; a waveguide convex mirror for slightly reducing a converging degree of light from the waveguide concave mirror; and photodetectors for receiving light from the waveguide convex mirror, The coupler, the waveguide concave and convex mirrors and the photodetectors are integrally formed on a substrate, An apparatus for recording and reproducing optical information has a light source; an optical system for converging light emitted from the light source; an optical waveguide; a coupler for coupling the converged light to the optical waveguide; two waveguide mirrors arranged such that reflected light from the coupler is continuously reflected on the waveguide mirrors; and a photodetector for detecting the light reflecte

Abstract: An optical disk includes a recording medium having a disk shape, and a plurality of signal pit strings formed on the recording medium and arranged in a circumferential direction of the optical disk. Each of the signal pit strings includes a plurality of signal pits arranged in a line in a radial direction of the optical disk. An optical pickup apparatus includes a photodetector having a plurality of photoelectric elements. A light spot is sequentially projected onto the signal pit strings, and a reflected light therefrom is converged by an objective lens. An image formed by the objective lens is detected by the photodetector located in an image forming position of the objective lens. The unit information pieces contained in one of the signal pit strings are simultaneously read by the photoelectric elements. In this manner, the signal pit strings are sequentially read while the optical disk is being rotated.

Abstract: An optical head for writing and/or reading information on and/or from an optical record medium such as a magneto-optical record medium including a semiconductor substrate, a semiconductor laser mounted on a surface of the semiconductor substrate for emitting a laser beam, an objective lens for projecting the laser beam onto the optical record medium as a fine spot, a plurality of photodetectors firmed in the surface of the semiconductor substrate, and an optical block arranged on said semiconductor substrate to form an integral unit together with said semiconductor substrate. The optical block includes a hologram for diffracting a return beam reflected by said magneto-optical record medium and a polarization beam splitting plane arranged in substantially parallel with an optical axis of a zero order beam emanating from the hologram for splitting a pupil of the hologram.

Abstract: An optical pickup for use in various optical recording/reproducing apparatus includes a general-purpose lamp producing a wide range of light wavelengths, a converging device for converging the light of the lamp, and a pinhole and color filter for enhancing the temporal/spatial coherence of the light. The lamp radiates light containing the intensity of a laser and spectral distribution characteristic of a laser.

Abstract: A semiconductor laser chip comprises a substrate and material layers successively formed on the substrate. The laser chip has an output cleavage face and emits an output laser beam which is inclined to the output cleavage face. The laser chip may be incorporated in a laser pickup device for optically reading information from an optical data carrier such as optical disk.

Abstract: A laser control system for use with an erasable optical disk device to minimize laser feedback during a recording operation. Focus control circuits are utilized to establish a slightly defocused condition prior to a recording operation and maintaining that slightly defocused condition throughout the recording operation. Defocusing the write beam significantly reduces feedback and thereby significantly increases pulse-to-pulse repeatability of the write pulse amplitude at the optical disk.

Abstract: An optical disk for recording audio and video information in unit of field or sector has a recording format that provides an area for recording all audio information to be recorded in each unit immediately after an area used to set the power of the optical beam to a desired level. Also, an audio and video information recording method using the optical disk having the recording format mentioned above is disclosed. According to this method, after-recording of audio information is made at a desired level of the power of the optical beam.

Abstract: A semiconductor laser device includes a semiconductor laser, a signal generating circuit, a modulation circuit and a drive circuit. The semiconductor laser has an active layer including at least two light-emitting layers having different energy levels. A high-frequency signal having a predetermined frequency is generated by the signal generating circuit. The signal width of the high-frequency signal is modulated by the modulation circuit in accordance with an information signal. The semiconductor laser is driven by the drive circuit in accordance with the signal modulated by the modulation circuit.

Abstract: An optical pickup apparatus has a pickup movable part of integrally driven type in which the number of signal wires connected to the pickup driver part is decreased, and auxiliary signal wires required hitherto need not be provided. The optical pickup apparatus includes a pickup driver part including a semiconductor laser emitting a laser beam for forming a spot of the laser beam on a recording surface of a recording medium, a control circuit controlling the operation of the pickup driver part, and a plurality of signal wires connected between the pickup driver part and the control circuit for the signal transmission and reception between them. The control circuit includes a signal selector for selecting one of a plurality of input signals and outputting the selected signal, and a counter for supplying signal selecting information to the signal selector in a time division mode, so that the plural input signals can be supplied by the plural signal wires in a time division multiplex mode.

Abstract: A laser beam controller of a semiconductor laser generator to read, write, and erase an information signal on a recording medium. Includes a generator of a variable-strength laser beam to read, write and erase the information signal on the recording medium; a first power supply of a first current to generate a laser beam to read the information signal; a second power supply of a second current to generate a laser beam to write or erase the information signal; and a controller circuit of the first and the second power supply.

Abstract: A plural-beam optical head is constituted by a monolithic semiconductor laser array having a plurality of light emitting points, a collimator lens for collimating laser beams emitted from the plurality of light emitting points, an objective lens for imaging the laser beams on an optical information recording medium, and a device for expanding the diameters of the laser beams in the direction of arrangement of the plurality of light emitting points. In the plural optical head, the following condition is satisfied:(d.multidot.f.sub.0)/(f.sub.col .multidot.m)<20 [.mu.m],where d is the maximum spacing between adjacent ones of the plurality of light emitting points, f.sub.col is the focal length of the collimator lens, f.sub.0 is the focal length of the objective lens, and m is the expansion magnification of the device for expanding the diameters of the laser beams.

Abstract: A multichannel optical head and data storage system employs an integrated-optical read channel. The read channel may be fabricated on a planar waveguide structure that separates the data signals of the multiple lasers. The read channel includes focus error sensors and track error sensors. The optical head may be used for amplitude recording systems such as phase-change erasable and write-once media, ablation media, dye-polymer media, and OD-ROM systems.

Abstract: The invention relates to an optical computing element for use in an optical computer utilizing computing light rays having a plurality of wavelength components. The optical computing element comprises a photo-chemical hole burning element which functions as a wavelength selecting filter of the computing light rays. Therefore, the optical computer using the photo-chemical hole burning element of the invention can perform arithmetic operations by taking advantage of differences in optical wavelength. The computer can efficiently perform bulky arithmetic processing, and can also speedily perform arithmetic operations through simultaneous parallel processing for information.

Abstract: A method for reproducing a magneto-optical recording medium the recording pits of which are erased or relieved with rise in temperature of the recording medium caused by radiation of a readout beam, or an optical recording medium the reflectance of which is changed with rise in temperature of the recording medium caused by radiation of the readout beam, in which, when the line recording density of the recording medium is changed, the size of the effective reproducing region is controlled to an optimum value conforming to the line recording density to assure a stable reproducing state.

Abstract: A method for reproducing a magneto-optical recording medium the recording pits of which are erased or relieved with rise in temperature of the recording medium caused by radiation of a readout beam, or an optical recording medium the reflectance of which is changed with rise in temperature of the recording medium caused by radiation of the readout beam, in which changes in the size of an effective reproducing region due to the temperature of the magneto-optical or optical recording medium may be inhibited. To this end, a temperature sensor 20 for sensing the temperature of the magneto-optical disc 11, for example, is provided and the laser power or the external magnetic field is controlled depending on the detected temperature by the temperature sensor 20 to maintain a constant size of the effective reproducing region at all times.

Abstract: An integrated light deflector and fabrication method are disclosed. In accordance with the method, a mold is constructed above the surface of a substrate using a thick photo resist and a mask to define a deflector plane. A collimated light beam is applied at an appropriate angle of incidence to the photo resist material and mask. The developed resist provides a mold into which the deflector body is cast, leaving a deflector body whose front surface serves as the deflecting surface.

Abstract: After a laser beam of a high-level laser beam is applied to a multilayer magneto-optical recording medium to record information thereon, a laser beam of a laser power lower than the laser power of a reading laser beam is applied or substantially no laser beam is applied for a period of time .tau..sub.0. If one channel clock period or the period in which the high-level laser beam is of the second laser power is applied is .tau..sub.w, then the ratio R=(.tau..sub.0 /.tau..sub.w).times.100 is selected to be in the range from 15 to 70%.

Abstract: An optical recording medium, typically an optical disc, has a recording region of a laser medium extending thicknesswise thereof, and a reference region positioned radially inwardly of the recording region for emitting reference light. The recording region has pits and lands formed on a surface thereof as representing recorded information. The pits and lands having respective first surfaces parallel to corresponding second surfaces on an opposite surface of the recording region. The first and second surfaces provide different thicknesses of the recording region. When pumping light emitted from a semiconductor laser, for example, is applied to the recording region, the recording region operates as optical resonators between the first and second surfaces for emitting laser signal light of a variable frequency depending on the recorded information. The optical resonators have respective optical axes extending thicknesswise of the recording region.

Abstract: The optical information recording and reproducing method and apparatus include a method for controlling a high frequency pulse current for driving a semiconductor laser device by which noise due to returning laser light is hardly produced, and an apparatus for increasing access speed owing to decrease in the weight of an optical pick-up movable part. Loser noise is suppressed satisfactorily by detecting the position of the optical pick-up movable part in a split optical system by means of a scale, and generating a pulse current for modulating the laser having a frequency optimum for reducing the laser noise to drive the semiconductor laser device.

Abstract: In an optical system for converging light beams to form a single beam spot on an optical disc, a light beam generated from a semiconductor laser is collimated by a collimator lens and is guided to a prism member. In the prism member, the light beam is divided into two segment beams having same intensity distributions which are similar to that of the generated light beam by a polarization beam splitting face. One of the segment beams is reflected to an objective lens and the other of the segment beams is guided to a wave surface changing member. Which change the configuration or distribution of the other segment beam. The other segment beam having a deformed intensity distribution is also guided to the objective lens from the changing member and is combined with the one segment beam to form the single beam spot on the disc.

Abstract: An optical recording system having a laser for generating a light beam to write data to and read data from a storage medium, an RF modulator for modulating the laser to improve its stability, and an apparatus for driving the laser. The apparatus is comprised of a transistor coupled to the laser for supplying current to the laser. An amplifier is implemented to drive the base of the transistor according to a microprocessor. Thereby, the microprocessor effectively controls the power level of the laser. The transistor and the RF modulator are enclosed within shielding to contain the RF energy being generated by the modulator. In addition, the collector-base separation of the transistor reduces the RF energy being transmitted through the line driving the base of the transistor.

Abstract: A pickup device can detect the frequency (pit length) recorded in the recording medium, and read out data signals from the optical disk at high S/N. Further, the data read speed is considerably increased since it is possible to concurrently read data signals from the tracks. In a pickup device, a linear light beam emitted from a light source is projected onto an optical disk through a condenser lens so as to form an image thereon, which is long enough to cover three recording tracks on a recording medium. Signal light reflected on the recording medium is imaged on a photo detector consisting of an array of detecting elements, and is detected and output by and from the photo detector. A frequency analyzer unit analyzes the frequencies of the detected signals. A computing circuit calculates the output values for each analyzed frequency. Accordingly, it is possible to separate the frequencies of the recording tracks from each other.

Abstract: In optical apparatus for reading, writing or erasing optical disks, the optical head is implemented in integrated form. Silicon optical bench technology, including integrated optical waveguides, Y-splitters and directional couplers, is used in the design of the tracking, lens focussing, and read/write/erase functions.

Abstract: A method and a device for recording and reproducing information utilizing a work function variation of a recording medium, the recording medium being made of a material whose work function can vary according to a structural change thereof caused by the irradiation of an electromagnetic wave or electron beam.

Abstract: A lens/mirror tower (LMT) of a multiple-disk array, optical storage system includes a plurality of lens and mirror elements integrally formed on a monolithic, optically-clear substrate. There is a specific lens/mirror set for each recording disk surface of the optical storage device; however, the mirror elements are preferably configured as one reflective surface of the substrate. The lenses are molded onto the opposite surface in a single operation that fixes their relative positions. The LMT is generally fabricated using a lens replication process. Initially, a glass substrate is formed with a trapezoidal configuration. A lens array mold is also formed with a plurality of cavities arranged in overlapping pairs. The cavities are filled with optical-quality resin and the mold is applied to the surface of the substrate opposing the reflective angular, e.g., 45.degree., surface. Once cured, the resin serves as an array of lenses that are aligned with the optical paths to the objective lenses of the disk array.

Abstract: An over-write capable magnetooptical recording medium is pre-processed by subjecting a track separation zone to a pre-processing field which aligns the magnetization of a recording layer in a predetermined direction so as to avoid formation, in the separation zone, of a magnetic wall between the recording layer and a reference layer when the reference layer is subjected to an initial field to align its direction of magnetization.

Abstract: An electronic circuit is described which will allow an acoustoptic deflector to be used in multi-frequency mode at high power levels with a minimum amount of intermodulation between each frequency. Reduction of interference between multiple separate signal frequencies is achieved by precise control of the individual phasing of each separate frequency relative to a common reference frequency. The relative phase of each frequency is also controlled so that a low maximum power is achieved for the combined signal that is presented to the acousto-optic deflector without decreasing the overall average power of the multiple signal frequencies. The present invention is useful in systems such as optical data storage on tape or disk, optical printing and imaging, and acousto-optic signal or information processing.

Abstract: A high density rapid access data storage device employs a volume of field-oriented bacteriorhodopsin in a polymer medium, and contained in a vessel that can be accurately displace in three dimensions. X-axis and Y-axis laser illumination systems each converge a beam in the respective direction at a location at which a particular bit cell is to have a "1" or "0" recorded or is to be interrogated. Both laser systems are pulsed on at one wavelength to write a "1" or at a second wavelength to write a "0". After writing, a cleaning step is carried out by actuating the laser systems non-simultaneously at the other of the wavelengths to remove any undesired photochemistry from adjacent bit cells. A read cycle involves actuating two or four lasers, and then discriminating the "1" or "0" state from the electrical signal generated by the medium.

Abstract: An optical recording/reproducing apparatus comprises a semiconductor laser, and a drive circuit for supplying a drive current to the semiconductor laser. A light beam from the semiconductor laser is converged on a recording medium through an objective lens. A photodiode for receiving the light beam is provided within the semiconductor laser. A monitor output from the photodiode is input to an APC circuit. The APC circuit includes a reference value generator and an error detector circuit. The error detector circuit detects a difference between the monitor output and a reference value, and outputs a control signal for controlling the drive circuit so as to keep the monitor output constant. The APC circuit is turned on/off by a controller. With the APC circuit turned on, the controller detects the temperature or temperature variance of the on the basis of the drive current monitor signal from the drive circuit and the pre-stored data of the semiconductor laser with respect to temperatures.

Abstract: A wavelength selective optical recording and reproducing method includes an optical recording and reproducing step of information composed of time series signals on a recording medium having recording tracks as position series signals with light having a variable wavelength while switching the wavelength between predetermined values.

Abstract: An objective lens drive apparatus applicable to an optical disk apparatus includes a base member disposed so as to oppose a recording surface of an optical disk and so as to be movable in a direction of a radius of the optical disk, a support mechanism supporting an objective lens on the base member and so as to be movable in the direction of the direction of the radius of the optical disk. The objective lens drive apparatus also includes a drive mechanism acting upon the support mechanism to move the objective lens on the base member, a displacement detector detecting a displacement of the objective lens on the base member, a controller controlling the drive mechanism so that the objective lens is maintained at a required position on the base member.

Abstract: An apparatus for recording onto and reading from an optical disk includes an array of laser diodes that emit a plurality of laser beams with each beam at the diode source spaced a distance greater than about 50 .mu.m from adjacent beams. The apparatus includes a plurality of channel waveguides coupled to the plurality of laser diodes with each channel waveguide associated with a respective laser diode for directing light emitted by the diodes toward the optical disk for optical recording and for receiving reflected light from the optical disk for reading the optical disk. Each beam emanating from the channels is spaced from adjacent beams a preselected distance less than about 50 .mu.m.

Abstract: A device for reading an optical recording medium which includes a source (1) for emitting a first light beam (F1) along a main optical axis (01); a beam splitter (2) to direct, along the main optical axis, the first light beam towards the surface of the recording medium (5), and to split a second beam (F2) obtained by reflection of the first beam on the surface of the recording medium so as to form a third beam (F'3) directed along a secondary optical axis; a focusing lens (4) between the splitter (2) and the surface of the recording medium to focus the first beam on the surface; a mask to introduce a dissymmetry into the third beam; and at least one detection device (7) receiving at least one part of the third beam (F'3) and giving at least one electrical signal expressing the detection made. In this device, the mask is formed by part of an external surface of the light-emitting source (1), and the splitter (2) is positioned and made so that the mask is in the focusing plane of the third beam (F'3).

Abstract: A magneto-optic recording and regenerating process and the device using it in accordance with the present invention are intended to magnetize the magnetic, or magnet, film of a disk parallel to the plane of the magnetic film to record or erase information. When regenerating information, light beams whose incident plane is substantially perpendicular to the direction of magnetization of the recording medium is applied to the disk, so that the recorded information is regenerated dependent on the light intensity of reflected light obtained in response to the direction and magnitude of magnitization of the disk. Additionally, the magneto-optic disk includes a magnetic film having a coercive force smaller than the saturated magnetization at room temperature, so that irradiating light beams elevate the temperature of the magnetic film but not up to its Curie temperature. Information is then recorded on or erased from the magnetic film with its coercive force decreased by the elevated temperature.

Abstract: In an optical data recording and reproducing apparatus comprising an information signal generator, a sample/hold switching signal generator, a write/read switching signal generator, a laser beam source, a reference voltage generator, a comparator and a photo detector, a dummy signal is added to the information signal modulating the laser beam or generation of the laser beam is forcedly stopped after a data write servo mode so as to prevent generation of the laser beam of an excessively high level at the time of change-over from the data write servo mode to a data write hold mode or from the data write hold mode to a data read mode, or the level of the write/read switching signal is changed before the level of the sample/hold switching signal is changed at the time of change-over from the data write hold mode to the data read mode, or the duration of emission of the laser beam is extended slightly before the level of the sample/hold switching signal is changed.

Abstract: Optical recording/reproducing apparatus of the 2-head or 3-head type uses a simplified controller but is nevertheless capable of high-speed read-after-write check. In a 2-head embodiment a switching circuit supplies either a reproducing output of a recording head or a reproducing output of a reproducing head to a signal processing circuit selectively. When the reproducing output of the reproducing head is supplied, a signal generator supplies a signal to the signal processing circuit corresponding to the reproducing output of the recording head. In a 3-head embodiment a circuit compares identification signals in reproducing outputs of an erasing head and a recording head, respectively, and supplies the recording head with data to be recorded from a FIFO memory. A 3-head embodiment may also use a switching circuit for supplying either a reproducing output of an erasing head or a reproducing output of a reproducing head to a signal processing circuit.

Abstract: An optical information reading and writing system, comprising an optical recording medium and a multibeam optical head optically coupled to the optical recording medium. The optical recording medium has a plurality of uniformly spaced tracks in a radial direction of the medium for recording information thereon. The multibeam optical head is movable in the radial direction of the medium and includes a laser diode and an image forming optics. The laser diode has a plurality of nonuniformly spaced lasing elements in a straight line for generating a plurality of spaced laser beams. The image forming optics directs each laser beam onto a respective tracks of the optical recording medium. The spacing between the adjacent laser beams on the tracks corresponds to the spacing between the adjacent lasing elements.

Abstract: A system and method for processing an optical information on an optical record medium are disclosed in which a timing at which a scanning of a light spot on one record track of the optical record medium derived from an acoustooptic deflector is started is controlled on the basis of a tracking error signal indicating that a scanning trajectory of the light spot is deviated from a center line of the one record track on the optical record medium. Therefore, the light spot can accurately be tracked on each record track on the high density optical record medium such as a tape in a simple construction.

Abstract: An array of diode lasers selected to emit at certain fixed wavelengths is assembled to temperature stabilzed Bragg reflectors to assure maintenance of the selected wavelength within 1 .ANG.. One laser is included in the array for each wavelength at which absorption will occur within a photochemically active optical storage medium. Each temperature stabilized laser is focussed by a lens onto an optical storage medium containing photoactive chemical components containing guest and hose molecules, as is known in the art. Light emitted by each laser will be used to burn a pit for each bit of data at the locations of the storage medium. One or more photodetectors located on the opposite side of the sotrage medium to detect the presence or absence of a hole with respect to the selected wavelength with which the hole was initially burned. A similar device is available with a temperature stabilized tunable laser which accurately controls the selected wavelength withing 1 .ANG..