Abstract: An optical recording/reproducing apparatus has a beam emitting device adapted to emit at least two light beams in directions at a minute angle to each other. The light beams are condensed by a condensing member onto slightly separated two points on a disk and reflected by the disk. The light beams from the disk are polarized to a prism by a polarizing device. The prism refracts the light beams from the polarizing device, thereby increasing the relative angle between the light beams. The refracted light beams are converged by a converging lens on a detector.

Abstract: An erasable optical read/write data storage system is disclosed. The data storage system utilizes a temperature sensitive data storage disk which includes an optical tuning film and a film of thermochromic phase change material which will change from a first phase to a second phase at temperatures in excess of an upper temperature and back to the first phase at temperatures below a lower temperature. An environmentally controlled chamber is provided to maintain the data storage disk at a selected bias temperature between the lower and upper temperatures to ensure that no unintentional phase change will occur. A thermally controlled support member is utilized to temporarily lower the temperature of the disk to a point below the lower temperature, thereby initializing the disk. A modulated laser beam is then focused on the disk to temporarily heat particular portions of the disk to a temperature in excess of the upper temperature, causing a phase change.

Abstract: In an optical reproducing apparatus a divergent beam from a semiconductor laser light source is collimated to form a parallel light beam that is converged by an objective lens and focussed on an optical record medium. The light beam is reflected by the optical record medium and introduced into a signal photodetector so as to provide a reproduced signal. A phase type diffraction grating between the semiconductor laser light source and a beam splitter separates the laser beam from the semiconductor laser light source into zero, plus first and minus first order diffracted beams. A pair of tracking photodetectors receive reflected beams of the plus first and minus first order diffracted beams reflected by the optical record medium and then by the beam splitter.

Abstract: A system is provided for transferring a series of images which are displayed successively on a screen of a video monitor using optical means, onto a photosensitive surface by juxtaposing successive elemental images to form a unique composite image. The composite image is directly created on the screen of the video monitor without the necessity of translationally displacing the various elements relative to one another to achieve the framing or to vary the magnification ratio. The composite image is created by successively sweeping various portions of the screen of a high-definition tube. The amplitude and the centering of the sweep signals are determined, as a function of the selected format, by converters run by programmable memories.

Abstract: An optical recording and reproducing apparatus includes a first semiconductor laser for emitting a recording laser beam whose intensity is modulated in accordance with an information signal to be recorded and a second semiconductor laser for emitting a reproducing laser beam having a constant intensity. The recording and reproducing semiconductor lasers are commonly mounted in a supporting member which is mounted on a pick-up plate arranged movably in a radial direction of a rotating optical disc. The recording and reproducing laser beams are composed with each other by means of a substantially parallelogram shaped prism having a reflection surface for reflecting the reproducing laser beam and an optical surface upon which the reproducing laser beam is made incident at an incident angle larger than a critical angle and the recording laser beam is made incident at an incident angle near Brewster's angle.

Abstract: Optical apparatus is disclosed for spatially combining and/or separating a plurality of reading and writing laser beams as required, for example, in an optical memory system. The apparatus includes a spatial combining and separating device comprising a thin transparent element which is provided with reflective and anti-reflective coatings and an appropriately located opening in a manner so as to permit the original and reflected writing beams to pass through the device without change in direction while the original and reflected reading beams are reflected from the device in predetermined directions.

Abstract: In an information recording apparatus for recording predetermined information on a recording medium by means of a laser beam, an optical system and a light detector are arranged for detecting a reflected version of the laser beam from the recording medium, whereby the focusing of the laser beam on the recording medium is automatically controlled.

Abstract: Disclosed is a radiant energy optoelectronic position monitor system which detects the angular position of a "galvonometer mirror" (beam scanner) used in an optical disk memory arrangement.

Abstract: Disclosed is a system for recording and playing back information utilizing a magneto-optical disc memory having a vertical magnetization film on and from which the information is recorded and read out by an optical means. In order to simplify the construction of the system, an optical system including an objective lens and a tracking mirror is used both as a part of an optical path of a recording light beam and a part of an optical path of a readout light beam. The wavelengths of the recording light beam and the readout light beam are selected to be different so that the light beams are easily discriminated in the optical system.

Abstract: An optical information recording and reproducing apparatus for recording and reproducing an information signal on and from a recording medium, respectively, having a recording track, and which includes a beam generator, having a laser, for generating a primary beam and first and second secondary beams of light arranged substantially in the same direction as the track on the recording medium, a focussing lens for focusing the primary beam and first and second secondary beams of light on the recording medium, and a detecting device having a primary photodetector for detecting a reflected primary beam from the recording medium and first and second secondary photodetectors for detecting reflected first and second secondary beams from the recording medium.

Abstract: A method and apparatus for producing a high intensity, ultraviolet, electronic video image is provided. The apparatus includes an electronic video imaging tube for printing on vesicular microfilm, diazo microfilm, and diazo paper and the like. The tube is constructed of a housing having an interior with an electron gun emitting a scanning electron beam across a path which intersects the interior of the housing. A phosphor target of ultraviolet phosphor is disposed within the housing interior and is positioned upon the path for reflecting therefrom a high intensity, ultraviolet video image. The phosphor target is preferably convex, and concentric with a curved surface portion of the housing. The curved surface portion of the housing reflects the high intensity, ultraviolet video image from the interior of the housing to the exterior portion thereof. A reduction lens assembly can be provided for diverging or converging the image as desired.

Abstract: An optical beam switch is provided in a multiple beam optical disc record and playback system. Current systems for very high data rate optical disc mass memory apparatus include requirements for near-continuous recording of data using two separate turntables in a single apparatus. To reduce cost and complexities in the system as well as power requirements, the optical system includes a beam switch that allows a single record laser and modulator to be shared between two turntables. In accordance with the system a half-wave plate is shifted into and out of the beam path to effect polarization change of the light beam. A polarizing beam splitter, which follows the half-wave plate in the beam path, shifts the light beam in one of two directions depending upon the polarization of the light beam or, in other words, the position of the half-wave plate.

Abstract: A single semiconductor laser (10) is utilized in an optical system (2) to record and readback from a recording media such as a spinning disk (24). By means of a retro-reflecting light and optical system, the same optical path can be used not only for recording, but for readback of the recorded data on the recording media (24). A polarizing beam splitter (16) causes the light beam (8) to pass through an optical system whereby both focus error and tracking error as well as the data signal can be generated. By dithering the light beam across the recorded track in accordance with data signal, a tracking error signal is generated to cause the dithering motion of the galvanometer (20) to maintain its center tracking of the recorded information. By the use of a separate beam splitter (30), a focus error signal can be detected by means of error signals from complementary detectors S1, S2 to maintain accurate focus of the applied light beam on the recording media.

Abstract: Information is stored by a process involving the steps of(1) sensitizing a recording medium comprising a two-photon, four-level material by exposing said medium to flood illumination with ultra-violet or visible light, and then(2) exposing the sensitized medium simultaneously to two beams of coplanar laser irradiation intersecting within said recording medium to create a microscopic interference pattern.

Abstract: An apparatus for recording, reproducing and erasing for an optical recording disc capable of recording information data with a high density, and capable of recording new information data and simultaneously erasing the previously recorded information data.

Abstract: A video disc record having a spiral video record track which can provide reproduced video signals with a desired frame rate such as thirty frames per second while the disc record is rotated at a very low speed such as two revolutions per minute. A preferred transducer machine uses a pulsed light source to supply successive light images to a video camera readout. Control signals are recorded on helical control tracks so that reproduction thereof facilitates the generation of a desired standard video signal from the video camera.

Abstract: An apparatus is described for reading a record carrier on which information is stored in an optically readable information structure, which apparatus includes a radiation source which supplies a read beam of great coherence length. By including a radiation attenuating element in the radiation path of the read beam, preferably nearest to the radiation source, random intensity modulations in the read beam, which modulations may be caused by undesired reflections in the radiation path, can be substantially reduced.

Abstract: Recovery from a record of data recorded in an elongated information track, comprising depressed areas of various lengths alternating with non-depressed areas, is effected by an optical playback system. The playback system employs apparatus for focusing a laser source as a light spot on the information track. A light detector, responsive to light diffracted by the information track as relative motion is established between the light spot and the information track, is used in the playback apparatus to translate the depressions in the information track into frequency-modulated electrical signals. When the light spot size or depression spacing becomes comparable to the wavelength of the laser source, the signal strength at the detector output becomes dependent upon the polarization of the light spot incident on the information track. In the playback system, apparatus is provided for orienting the polarization of the light spot on the information track to enhance the signal strength of the detector output.

Abstract: A method of replicating data from a master transmissive optical data storage medium whereby the resulting product displays areas of low reflectivity and high reflectivity. Actinic radiation is shone through transmissive areas onto a silver-halide emulsion photosensitive medium. The photosensitive medium is then chemically developed black. Next, the developed medium is fogged to create a latent image layer of silver precipitating nuclei. Finally, the fogged medium is placed in a monobath comprising a weak silver-halide reducing agent and a rapid-acting silver-halide solvent for partial chemical development and substantial physical development. The resulting product displays areas of low reflectivity, which correspond to the transmissive areas of the master, in a reflective field.

Abstract: The invention relates to an optical recording system and method in which information can be recorded and read by means of laser light on a recording medium. The recording medium comprises a circular substrate plate which is manufactured, for example, from a transparent synthetic resin and has a diameter from 5-50 cm and which is provided on at least one side with a recording layer consisting entirely or substantially entirely of a compound of phthalocyanine with a metal, metal oxide or metal halide. A very suitable recording layer is a layer of vapor-deposited vanodyl phthalocyanine in a maximum thickness of 200 nm. A metal layer of, for example, tellurium may be provided between the substrate and the recording layer or on the side of the recording layer remote from the substrate. The recording medium may also comprise an optically readable servo track. Upon recording information the element is exposed to pulsatory laser light, pits and/or holes being formed in the recording layer.

Abstract: A holographic video disc system is described in which the baseband information for successive horizontal television line intervals is recorded as successive holograms of one-dimensional line images in a spiral track on the surface of a disc of material. A spiral guiding track is also formed in the surface of the disc immediately adjacent to the spiral track of holograms. The recording system includes a laser beam which is modulated with the baseband video information. The beam is divided into a reference beam and a data beam. A beam deflector scans the data beam through a chosen angle at the horizontal television sweep rate, while the reference beam is unaffected. The reference beam and data beam are intersected at the surface of a record medium and form a surface relief hologram on that surface.

Abstract: In an optical information recording apparatus, a version of a recording light emitted from a light source and reflected by a recording medium is detected to control the recording light output power of the light source.

Abstract: A high speed data storage and retrieval system includes a storage module, a reader and a changer apparatus. A protective cartridge is provided for storing, protecting and transporting an optical disc enclosed therein. The storage module includes pins for insertion into corresponding holes in one surface of the cartridge during storage. During transport the changer apparatus having electromagnetic means grips the cartridge by spring clips attached to the cartridge. A window cut in the side of the protective cartridge effects readability of the disc enclosed therein without removing the disc from the cartridge during the reading operation. The cartridge also includes a set of holes in another surface of the cartridge for receiving a corresponding set of pins when the enclosed optical disc is placed in the read position.

Abstract: A high speed data storage and retrieval system includes a disc storage module, a reader and a disc changer apparatus. Disc records enclosed in protective cartridges are transported between the reader and the storage module by the changer apparatus. The reader includes two mechanical systems--a system for receiving, securing and spinning a disc while it is enclosed in the cartridge and a pair of read heads which retrieve data stored on the surface of the disc. The storage module includes a plurality of storage locations for storing the discs. The changer apparatus comprises a carriage with a drive mechanism for driving the carriage the length of the storage module and at least two carriers for transporting discs with independent drive mechanisms. The carrier drive mechanisms drive the carriers in a direction normal to the direction which the carriage is driven. Simultaneous movement of the carriage and carriers permits high speed access of data.

Abstract: A laser beam is directed at the groove of a conventional disc phonograph record as it rotates, creating a reflected interference/diffraction pattern of the groove walls. The magnitude and rate of displacement of the interference/diffraction pattern is sensed and converted into an audio reproduction signal of the original phonograph recording.