Abstract: An optical information recording/reproducing apparatus realizes a direct verifying operation with a simple structure. A light beam emitted from a light source is converged on a track provided on an optical recording medium which is adapted to be moved relatively to the light beam. A super-resolution optical filter is provided in an optical path between the light source and the recording medium. The optical filter functions to produce a first light spot and a second light spot to be irradiated on the track such that the light intensity of the second light spot is lower than that of the first light spot and a recording signal is recorded using the first light spot. The signal recorded on the recording medium using the first light spot is reproduced by use of the reflected light caused upon the irradiation of the second light spot on the recording medium.

Abstract: A magneto-optical recording method employs a magneto-optical recording medium having a first magnetic layer which exhibits a low coercive force at room temperature and a high Curie temperature and a second magnetic layer which is exchange-coupled to the first magnetic layer and which exhibits a higher coercive force and a lower Curie temperature as compared with those of the first magnetic layer. A magnetic field modulated in accordance with information to be recorded is applied to the magneto-optical recording medium while irradiating it with a light beam of a constant intensity so as to record the information. The recorded information is simultaneously confirmed by using a reflected light of this light 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 information processing apparatus is provided for at least either recording or reproducing information by projecting a converging light beam on a recording medium. The optical information processing apparatus includes a light detector for receiving the light beam, a neural network for inducing a tracking or focusing error signal from an output signal of the light detector, and a servo device for performing a tracking or focusing servo operation in accordance with the tracking or focusing error signal induced by the neural network.

Abstract: An optical information recording and reproducing apparatus for recording information pits on an information track by irradiating a light beam focused into a fine spot onto the information track of an optical information recording and reproducing medium, includes a device for forming a plurality of recording light spots on the information track transversely to the information track.

Abstract: An optical information recording/reproducing apparatus provided with a device for irradiating an information track of an optical information recording medium with a preheating light beam. Simultaneously, a recording/reproducing light beam irradiates a light spot of the preheating light beam on the recording medium. The light intensity of the preheating light beam is varied in accordance with the environmental temperature of the apparatus detected by a detector. By such a construction, the recording/reproducing condition of information is kept constant, irrespective of the environmental temperature.

Abstract: In a method or apparatus for reading information from each of a plurality of information tracks arranged in a longitudinal direction on an information recording medium by relatively moving the information recording medium the orthogonally to the longitudinal direction of the tracks relative to a sensor array for reading information from the information tracks, wherein relative skew between the direction of arrangement of sensors of the sensor array and the longitudinal direction of the track is detected, and information is read from the information tracks while the recording medium and the sensor array are relatively moved in the longitudinal direction of the information tracks and, if desired, while the sensor array and the recording medium are relatively moved in such a manner as to compensate for deviation of an information reading area of an information track from a proper position caused by the skew in the course of the relative movement, based on the result of the detection.

Abstract: Disclosed is a method of recording information on a magnetooptical recording medium, which medium includes a first magnetic layer and a second magnetic layer having a lower Curie temperature and a higher coercive force at room temperature than those of the first magnetic layer. The second magnetic layer is exchange-coupled to the first magnetic layer. The first magnetic layer has a higher compensation temperature than the Curie temperature of the second magnetic layer. The method of recording information includes applying a magnetic field, which is modified in accordance with information from a magnetic head, to the medium to record information on the first magnetic layer and scanning the medium with a light beam to heat the medium to a temperature at least near the Curie temperature of the second magnetic layer so as to transfer the information recorded on the first magnetic layer to the second magnetic layer.

Abstract: An optical information recording medium includes a recording surface formed by a recording layer provided on a substrate, the recording surface being provided with parallel information tracks each divided into plural blocks, each of which is formed by a data area for information recording and a servo area for forming prepits for tracking signal detection, wherein the data area has a separating part the height of which is different from that of the information track and which is provided between information tracks adjacent to each other, and the difference in height is equal to or larger than the thickness of the recording layer, and wherein the servo area is not provided within the separating part.

Abstract: An optical head device comprises a light source, a light splitter for reflecting a light emitted from the light source by a first plane thereof to direct the light to an information carrier and transmitting the light from the information carrier through the first plane, a photo-detector for detecting the light from the information carrier, and a diffraction grating structure arranged on a second plane of the light splitter for diffracting the light transmitted through the first plane and directing it to the photo-detector.

Abstract: An information recording medium comprising a plurality of information tracks on which information is recorded, and separating regions for separating each of said information tracks from the other information tracks, each of said separating regions including a record section consisting of code of a shape or magnitude different from code in said information tracks.

Abstract: In an information reproducing apparatus and method for reproducing information from an information recording medium containing plural digital information data units and a parity bit attached to each data unit, the plural data units and parity bits of the recording medium are read plural times, the parity of each of plural data units thus read is counted, the parity value thus counted is compared with the parity bit value read as above, and the read information with least number of parity errors is selected to be output, based on the result of the above comparison.