Abstract: An optical head device for irradiating a light beam onto a recording medium to optically reproduce information recorded on the recording medium, the device includes a light source for generating a light beam to project onto the recording medium, a detector for detecting the light beam reflected from the recording medium, and an optical system for leading the light beam from the light source to the recording medium along a first optical axis and leading the light beam reflected from the recording medium along the first optical axis to the detector. The device further includes a half mirror arranged between the optical system and the recording medium, for reflecting a part of the light beam led to the recording medium toward the optical system to lead the part of the light beam onto the detector. The half mirror is tilted at a prescribed angle against the first optical axis to lead the part of the light beam reflected along a second optical axis differ from the first optical axis to the detector.

Abstract: A method of reading data from an optical disk comprises providing means for illuminating the required part of the disk and acquiring the optical image of a plurality of tracks, providing a detector matrix comprising a plurality of detectors, each of the detectors being capable of producing an output signal which is proportional to the intensity of the light detected by it causing an optical image corresponding to an illuminated area to fall on the said detector matrix, transferring the output signal of the detector matrix to image processing means, determining position coordinates of the track center for each data track, by analyzing the output signal of the said detector matrix, saving in memory means expected track center data, comprising position coordinates of the track center located by the analysis of the output signal, and if an actually detected track center is shifted with respect to the expected track center, electronically moving the track center position.

Abstract: A remote fine positioning mechanism of an optical storage device includes a stationary galvanometer-controlled mirror (galvo mirror) and an imaging lens, the imaging lens positioned to provide an image of the galvo mirror at the front focal point of an objective lens mounted to an optical head assembly. The galvo mirror functions as a beam steering element that is rotated about a steering axis to change the angle of incidence of a collimated laser beam with respect to the objective lens during track selection operations. Thus, for rotation of the galvo mirror to change the direction of the laser beam, the system operates as though the mirror were physically located at that focal point. To perform the imaging function, the imaging lens decollimates the beam. A collimation-correction lens is therefore provided to ensure, in combination with the imaging lens, that the laser beam remains collimated when it reaches the objective lens.

Abstract: Parallel laser beams #1, #2 and #3 produced by splitting one laser beam into three, are introduced to an optical scanning device along the central axis of a recording cylinder, the optical scanning device being disposed on the central axis of the recording cylinder and rotated thereabout, having an inclined mirror surface, the recording cylinder holding a recording sheet on an interior surface thereof.

Abstract: An optical recording and reproducing apparatus is provided with a light source that emits a beam of light, a rotatable head including a deflector that deflects the beam in a predetermined direction and an objective lens group which forms an image of the beam on an optical recording medium. The rotatable head rotates about an optical axis of the beam which is incident upon the rotatable head. A movable lens group, provided in an optical path of the beam between the light source and the rotatable head, is movable in at least an optical axis direction.

Abstract: An optical recording device forms on a magneto-optical disk 10 a recording mark corresponding to a recording data by focusing a light beam d into a light spot on a projection start position on the moving magneto-optical disk 10 and by raising the temperature of a portion of the magneto-optical disk 10 exposed to the light spot. An optical reproduction device includes a light-beam deflecting section 2a having a polygon mirror 8, a holographic disk, and a plurality of semiconductor lasers for repeatedly performing a unidirectional scanning in synchronism with recording data or a recording clock signal by moving the light spot from the projection start position in a direction equal to the moving direction of the magneto-optical disk 10 and to follow the moving speed of the magnet-optical disk 10.

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 optical record reproducing device including a movable optical system for moving along a radial direction of an optical disc, a separated optical system including a light source and a separated fixed optical system, a tracking control system having a reflective mirror for reflecting a laser beam irradiated from the light source toward the movable optical system and an accurate angular displacement mechanism including an angular displacement detector for directly detecting an angular displacement of the reflective mirror so as to control the movable optical system accuarately.

Abstract: A telecentric rotary actuary in an optical storage system. A laser generates a laser beam which is focused by an objective lens onto an optical disk in order to write data to and read data from the optical disk. In performing a seek, a galvo rotates a mirror in order to reflect the laser beam to different radial displacements in reference to the optical disk. The position of the laser beam is detected, and a rotary actuator, to which the objective lens is attached, follows the movement of the laser beam. A telecentric optical system comprising a relay lens and an image lens is used to minimize an offset between the laser beam and the objective lens. The relay lens focuses the laser beam to a back focal point. The image lens optically conjugates the back focal point to a front focal point corresponding to the objective lens in order to demagnify any offset.

Abstract: A device for accessing and following tracks on a surface of mobile media on which data is optically readable and writable by a laser beam. The device includes at least one optical head made of a rigid carriage which enables a laser beam (F) to access the track. A lens is rigidly linked to the rigid carriage (3) and focuses the laser beam on the surface of the mobile data medium. A return mirror is rigidly linked to the rigid carriage to direct the laser beam towards the lens. At least one motor coil allows movements of the carriage to focus the laser beam. A mirror which is not fixed to the optical head allows the laser beam to be directed towards the optical head, and a motor coil allows the mirror to pivot. Also means are provided for detecting and correcting any decentering of the beam in relation to the axis perpendicular to the plane of a pupil of the lens and passing through its center.

Abstract: An optical system for an optical information recording/reproduction apparatus, includes a light source, an objective lens for focusing a light beam from the light source on a recording medium, a beam splitter arranged between the light source and the objective lens, a detector for detecting a light beam split by the beam splitter, a galvano mirror arranged between the objective lens and the beam splitter, the galvano mirror having an opening, and a sensor for receiving the light beam from the light source via the opening.

Abstract: An optical disk apparatus has a galvanic mirror error signal generation circuit for detecting that the galvanic mirror rotates more than an allowed limit value in directions P and Q. When it is detected by the galvanic mirror error signal generation circuit that the galvanic mirror rotates more than the allowed limit value, the light intensity of the light spot is changed from the recording-use (or erasing-use) light intensity into the reproducing-use light intensity. Accordingly, recording and erasing of information is always carried out by the projection of the light beam having a predetermined light intensity, thereby always providing a high grade of optical disk apparatus.

Abstract: Tilt error detecting apparatus detects a surface tilt of a disc (26) and produces a tilt-error signal (TE) for servo control of optical pickup which is to follow the surface tilt. The apparatus has a movable portion (B) carrying an objective lens (16) for writing/reading optical information on/from a recording surface (26A) of the disc and a mirror (52) or a semi-transparent mirror (24) movable together with the objective lens, and a stationary portion (A) carrying a light beam source (10, 12, 14, 22, 50) for projecting a detection beam (LC.sub.1) to the recording surface through the mirror. The detection beam is reflected at the mirror like recording surface and forms a reflected beam (LC.sub.2). Aperture is provided on the stationary portion for passing a part of the reflected beam, the partly passed reflected beam is projected on a detector which produces the tilt-error signal depending on a position of a beam spot (LC3) produced thereon by the partly passed reflected beam.

Abstract: In a preferred embodiment, the invention relates to systems and methods for storing digital video information on an optical recording medium comprising the steps of moving the optical recording medium in a first direction, sinusoidally scanning a beam of light over the moving optical recording medium in a second direction substantially perpendicular to the first direction to establish a scan path over the optical recording medium, and periodically deflecting the sinusoidal scanning beam in the first direction to linearize at least a portion of the scan path. By linearizing at least a portion of the scan path, two traces can be made per cycle of a primary sinusoidal deflection, thereby doubling scanning efficiency.

Abstract: An optical head for recording, reproducing or erasing data by emitting a light beam irradiated from a light source onto a recording medium. To reduce the height of the optical head, an optical axis shifting device is disposed between a light beam emitting device and a condensing device for condensing the light beam onto the recording medium. This optical axis shifting device shifts the first optical axis of the light beam from the light beam emitting device to a second optical axis positioned in parallel and spaced apart from each other. As the optical axis shifting device, there is preferable employed a prism having two reflecting faces lying in parallel, and the optical axis, after shifting is to be positioned downwardly of the position of the optical axis before shifting, thereby reducing the height of the optical head.

Abstract: A galvanomirror unit including a housing, a yoke supporting a galvanomirror to adjust the angular position thereof, and a retainer secured to the housing. The galvanomirror unit further includes an initial position adjusting mechanism provided between the yoke and the retainer to support the yoke, so as to adjust the angular position thereof in the vertical and horizontal directions, with respect to the retainer.

Abstract: An optical data storage system comprises an optical data storage medium, a moveable optical head, and a fixed optical system. The fixed optical system comprises a focussing system and a fine tracking system. The fine tracking system achieves displacement of the beam spot on the optical medium without displacing the central axis of the beam from the aperture of the objective lens in the optical head. A low mass optical head is achieved without loss of light at the objective lens.

Abstract: A galvanomirror unit including a galvanomirror for reflecting a laser beam and a driving mechanism which adjusts the position of the galvanomirror to change the direction of light reflected by the galvanomirror. The driving mechanism includes a torsion spring to which the galvanomirror is secured and which is made of a leaf spring lying in a plane substantially parallel with the direction of gravity when in a free state.

Abstract: The present invention relates to a method and apparatus for high speed reading of multiple data tracks stored on an optical recording medium, such as a flexible optical tape. Data can be accurately read in the presence of position and alignment errors illuminating plural tracks of the optical recorded medium with an expanded light beam.

Abstract: An optical disk apparatus has a light source, light focusing means for focusing the light beam to a recording film of an optical disk light reception means for receiving a reflected light beam from the recording film, and optical axis adjustment means arranged in an optical path between the light source and the light focusing means and for adjusting a dislocation of the optical axis of the light beam from the optical center axis of the light focusing means. The optical axis adjustment means has an light transmissive flat plate having parallel surfaces which are installed diagonally to the optical axis, or with the light transmissive flat plate and means which supports the light transmissive flat plate and inclines rotatably the direction of the light transmissive flat plate around two axes by turning a curved surface seat thereof.

Abstract: An optical read/write apparatus includes an optical device for directing a main scanning spot and a pair of satellite spots, one on either side of the main scanning spot, onto a recording. It further includes a wobbling device for moving the satellite spots in relation to the main scanning spot. The satellite spots are moved with an oscillatory motion in a direction perpendicular to tracks on the recording medium. A tracking control device detects light reflected from the satellite spots, generates a tracking error signal, and moves the main scanning spot according to the tracking error signal in a direction perpendicular to the. This keeps the main scanning spot accurately centered on a track without offset and without wobbling the main scanning spot.

Abstract: In an apparatus for recording and reproducing optical information, a light beam from a semiconductor laser is reflected by a rotatable tracking mirror and is converged by an objective lens disposed on a carriage to form a small light spot on an optical information recording medium so as to perform recording, reproducing and erasing operations of the information.

Abstract: An apparatus for supporting an objective lens projecting a light beam upon an optical record disc having a data track recorded therein, movably in a focusing direction parallel to an optical axis of the objective lens as well as in a tracking direction perpendicular both to the optical axis and to the track in order to effect focusing and tracking servo controls, including four resilient wires arranged between a lens holder and a stationary base member, said resilient wires being not in parallel with each other. Two resilient wires provided nearer to the optical record disc are arranged such that extensions of these wires intersect with each other at a first point to make a first apex angle and the remaining two wires are arranged such that extensions of these wires intersect with each other at a second point to form a second apex angle, the first and second points being aligned in the focusing direction and the first apex angle being smaller than the second apex angle.

Abstract: There are provided an optical disc and an optical recording apparatus to form a tracking groove onto an optically recordable disc. This apparatus comprises: a recording beam generator to generate a recording beam such as a laser beam having a predetermined spot size so as to form a pattern of a predetermined width onto the disc; a light deflector arranged on an optical path of the recording beam generator; and a driver for driving the light deflector for reciprocally moving the recording beam in a radial direction of the disc at a high frequency, and for multi-exposing the disc by the recording beam due to the movement of the recording beam in the radial direction, whereby a groove having a width wider than the pattern of the predetermined width is formed. With this apparatus, both the discrete information pattern and a groove are formed by using a single recording beam. Namely, both the pits and a wide groove can be formed by using a single recording spot.

Abstract: In an optical card reproducing apparatus in which an optical card such that data is recorded as a plurality of track trains on an optical recording medium is reproduced and the data is optically detected by detecting the reflected light of the irradiated light from a light source by the optical recording medium, there are provided a memory to record the level of the output signal from the photo detector and a comparator for sequentially comparing the level of the output signal stored in this memory with the level of the output signal from the photo detector obtained by the next scan, and as the result of the comparison, when the output level from the photo detector is higher than the output level read out of the memory, the content of the memory is sequentially rewritten into the higher output level.

Abstract: A light beam deflection device comprises an acoustooptic element including a piezoelectric crystal base with a first flat surface and second and third flat surfaces each perpendicular to the first flat surface and opposite to each other and a transducer attached to the first flat surface of the piezoelectric crystal base and supplied with a deflection control signal, a first lens element having a first cylindrical surface forming a cylindrical lens and a first slanted flat surface opposite to the first cylindrical surface and disposed so that the first cylindrical surface faces the second flat surface of the piezoelectric crystal base, and a second lens element having a second cylindrical surface forming a cylindrical lens and a second slanted flat surface opposite to the second cylindrical surface and disposed so that the second cylindrical surface faces the third flat surface of the piezoelectric crystal base.

Abstract: A micro optical head, for optically reading and/or writing digital data on a recording medium in which digital data 1 and 0, corresponding to a high reflection factor and a low reflection factor, is composed of a self-coupled semiconductor laser located close to the recording medium. A bias current of the laser is determined so that it is smaller than a first threshold current, in which the medium has a low reflection factor, and is higher than a second threshold current, in which the medium has a high reflection factor. Output light of the laser is either strong stimulated emission light, corresponding to the high reflection factor, or weak spontaneous emission light, corresponding to the low reflection factor. The present head is carried on a flying slider with a spacing length less than several .mu.m which provides a small beam spot of about 1 .mu.m, and has an excellent signal to noise ratio.

Abstract: An optical head device comprises a semiconductor laser beam source, a diffraction grating for deflecting a laser beam emitted from the laser beam source at an angle of about 90.degree., a beam splitter placed between the laser beam source and the diffraction grating, and an objective for converging the laser beam deflected by the diffraction grating on an optical disc.A surface of the grating is formed at an angle of inclination in the range from 0.degree. to 45.degree. with respect to the central optical axis of the laser beam emitted from the laser beam source so that a reflecting diffraction beam caused by the diffraction grating is used as a deflected beam.

Abstract: An optical storage apparatus for storing and reading information on an optical disk with an optical beam, including a tracking servo system having an objective lens, which is driven in a focusing direction F and a tracking direction T by a lens actuator, and a tilting mirror, which is rotated by a mirror actuator. The tracking servo system eliminates beam shift by controlling the lens actuator and the mirror actuator to position the lens and the mirror so that the laser beam always passes through a back focal point of the lens located on the opposite side of the lens from the optical disk. As a result, the laser beam proceeds from the lens to the disk along a path which is parallel with the optical axis of the lens and strikes the disk perpendicularly. Accordingly, the return path of the laser beam reflected by the surface of the disk coincides with the incident path of the laser beam, and no beam shaft is experienced.

Abstract: In the present invention, there is provided an abnormality detector circuit for comparing a scanning width signal with an upper limit setting signal and a lower limit setting signal and detecting that a scanning width indicated by the scanning width control signal becomes larger than an upper limit scanning width indicated by the upper limit setting signal or becomes smaller than a lower limit scanning width indicated by the lower limit setting signal, whereby when a signal level of an electrical input signal indicative of an information to be recorded exceeds a proper range, this can be positively discriminated by an operator.

Abstract: 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 reflecting or deviating mirror. According to the invention the rotation axis of this mirror is in the plane of the entrance pupil and of the focus of the focusing lens.

Abstract: This invention is to provided in such an information recording apparatus in which when an exposing locus is formed on a film by irradiating on the film an exposing beam whose width is changed in response to an input audio signal, the average level positions of the exposing locus is controlled in response to the signal level of the input audio signal, a level detector circuit for comparing the input audio signal with a predetermined reference level signal, a continuous circuit for making the compared output from the level detector circuit continuous, a first integrating circuit for integrating the continuous output from the continuous circuit and a second integrating circuit for integrating the integrating outputs from the first integrating circuit and delivering the same as the average level position signals used upon the exposure and recording.

Abstract: An optical beam modulation and deflection device having a semiconductor laser mounted on a rotator which employs a rotating transformer so as to supply electrical power to the rotator in a contactless manner.

Abstract: A two-stage beam positioning apparatus for use in an optical data storage device is provided. A fixed assembly includes a light beam source and detector, light beam focusing and track following apparatus. The fixed assembly is optically coupled to a movable assembly which provides coarse positioning of a focused light spot on a data storage medium such as an optical recording disc. The coarse positioning assembly is mechanically independent from the light beam source and detector assembly and, therefore, may be made very stiff and light resulting in a high bandwidth and reduced data access time. Since the light beam source and detector assembly and the focusing and track following control apparatus are mechanically isolated from the movable coarse positioning assembly, the size and mass of these components are not critical and do not affect data access time.

Abstract: 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 reflecting or deviating mirror. According to the invention the rotation axis of this mirror is in the plane of the entrance pupil and of the focus of the focusing lens.

Abstract: The camera or data recording apparatus (30) consists of an optical system for creating a data record on a photosensitive medium and includes a laser (36) for generating a light beam and mirrors (62, 72, 74 and 82) for transmitting the light beam to a final light beam path (56e) which is rotated about an axis (63) parallel spaced from the final light beam path (56e). Further the camera (30) includes an assembly (38) for shaping and focusing the light beam to have a bar shape cross section which is directed to the rotating final light beam path and imaged onto a photosensitive medium (86). A modulator (58, 60) modulates the light beam from the laser (36) intermittently to image or record light beam bar shape cross sections defining data in an arcuate path (14) on the photosensitive medium (86), a computer (32) controls the modulator (58, 60) and a carriage (88) is provided for moving the photosensitive medium (86) toward and away from the axis (63) about which the final light beam (56e) rotates.

Abstract: A device makes it possible to eliminate the imbalance of a deviating mirror of an optical system which illuminates a data medium or support when that mirror is subject to rapid displacement. The imbalance is cancelled by the use of a photodetector device which receives the light reflected by a reflecting element positioned around the objective of the optical system which illuminates the medium. A control device then makes it possible to control the position of the mirror based upon the light given off by the reflecting element.

Abstract: An optical tape recorder is disclosed using the linear motion of a slide to record data across a slowly moving tape made of light sensitive material. Data is recorded on the tape by modulating the output of a laser in accordance with the data and focussing the modulated light onto the tape using a lens mounted on a slide. The position of the slide is measured using a linear optical encoder and this information is used to place the data accurately on the tape. The slide is connected to a spring and driven electromagnetically at its resonant frequency.

Abstract: An apparatus for optically reading a recording medium having information tracks disposed on alternating inclined recording surfaces preferably arranged in separate but alternately interposed spirals inclined at different angles on the medium. The apparatus includes photodetectors for detecting light reflected from each of the tracks, and circuitry for controllably combining the signals from the photodetectors to minimize crosstalk in the recovered signals.

Abstract: A video signal play back device derives video signals from successive tracks formed as a continuous spiral on a video disc using a light source and a lens system, which is carried by a rotatable element at a predetermined spacing from the surface of the disc and which defines a folded optical path. The rotatable element translates the lens system in the radial direction relative to the disc for "coarse" steering of the light beam along the information tracks as the disc is rotated by a turntable. The optical path includes a mirror which is articulated for rotational motion about an axis which shifts the point of impingement of the transmitted light beam upon the disc in the radial direction. The returned beam is directed to a photosensitive pick-up which provides input signals to a circuit which generates a "fine" servo control signal to drive the articulated mirror.

Abstract: A movable mirror device for an optical information recording and reproducing system has a base portion with a bottom section and an up-standing section extending from the bottom section. A permanent magnet having opposite magnetic poles at opposite ends thereof is fixedly mounted on the bottom section of the base portion. A pair of yokes have their ends engaged with opposite ends of the magnet, respectively. A plate member is supported by the up-standing section of the base portion disposed between the other ends of said yokes and a movable portion having a core. A mirror substrate is supported by an end plate formed on one end of the core and a mirror is fixed to the mirror substrate. A supporting portion provided on the other end of said core pivotally supports the core with respect to the up-standing section and a coil portion is wound around the mirror substrate.

Abstract: There are provided an optical disc and an optical recording apparatus to form a tracking groove onto an optically recordable disc. This apparatus comprises: a recording beam generator to generate a recording beam such as a laser beam having a predetermined spot size so as to form a pattern of a predetermined width onto the disc; a light deflector arranged on an optical path of the recording beam generator; and a driver for driving the light deflector for reciprocally moving the recording beam in a radial direction of the disc at a high frequency, and for multi-exposing the disc by the recording beam due to the movement of the recording beam in the radial direction, whereby a groove having a width wider than the pattern of the predetermined width is formed. With this apparatus, both the discrete information pattern and a groove are formed by using a single recording beam. Namely, both the pits and a wide groove can be formed by using a single recording spot.