Matches 351 - 400 out of 540 < 1 2 3 4 5 6 7 8 9 10 11 >
Match Document Document Title
5280466 Optical disc and apparatus for reproducing signals recorded on the same  
An optical disc is provided with: a signal track formed on a signal recording surface of the optical disc; and a plurality of cross-talk detection areas each formed on a portion of the signal track...
5278816 Recording/reproducing system using wavelength/depth selective optical storage medium  
Apparatus and method for encoding information and recording same as sets of variably spaced related marks stored in wavelength (color) and/or depth selective layers on the optical record wherein...
5278814 Apparatus for recording and reproducing information on and from an optical disk  
An apparatus for recording and reproducing information on and from an optical disk is disclosed in which at least one optical beam and a reference clock signal are used. The optical disk comprises...
5272686 Servo signal generator for optical disk driving apparatus  
An optical disk driving apparatus for driving an optical disk which comprises annular tracks having a data area and a servo area. Center servo data pits are disposed on and along a track center....
5270991 Track format for use with an optical record carrier having a varying track pitch  
The present invention provides a track format for an optical record carrier that is useful in producing a tracking signal with a substantially constant slope at its zero-crossing point for a range...
5268803 Disc memory apparatus utilizing detection of high-accuracy address data in short servo sectors for high speed accessing  
A disc memory apparatus allows its magnetic head to reach a target track in a short period of time, wherein address data is recorded on each two-track width corresponding to each of the...
5268887 Optical recording medium having offset-compensating areas  
A optical recording medium having guide grooves which are parallel or substantially parallel, tracks formed among the guide grooves, offset-compensating areas spaced apart in lengthwise direction...
5262907 Hard disc drive with improved servo system  
A hard disc drive having a digital servo system for controlling the position of a servo head on a dedicated servo surface. The servo surface is formatted in a series of consecutive frames along...
5257250 Tracking-control target-position adjustment method  
A tracking control target position adjusting track is provided on a recording carrier, where the track contains a preliminarily recorded first position-adjusting signal adjoining one side of track...
5253131 Servo pattern for location and positioning of information on a disk drive  
A servo pattern which provides for reference clock synchronization, track following and track crossing, and radial and angular head position information, is described. On each servo track, no two...
5253241 Optical recording apparatus for recording auxillary signals used for focus control  
An optical recording apparatus for automatically compensating for focus offset which cannot be compensated for with a conventional focus servo circuit. A plurality of auxiliary signals differing...
5251194 Techniques for controlling beam position and focus in optical disk drives  
An optical disk drive for recording and reproducing information on an optical disk medium includes a servo circuit for controlling tracking of a light beam on a predetermined track and a servo...
5249169 Apparatus for reproducing information  
An apparatus for reproducing information converts read signals for servo fields and read signals for data fields recorded on an optical disk to digital data. The input range of the A/D converter at...
5247507 Optical scanning system for a sinusoidal data track  
An optical scanning system for a compact disc having a sinusoidal data track radially meandering, at a selected frequency, about the axis of rotation of the disc includes a first laser beam for...
5235582 Photochromic optical disk read/write apparatus which prevents deterioration of the stored information during tracking and reading  
A photochromic optical disk read/write apparatus is provided having, in addition to the beams of light for reading and writing, a tracking light beam which is used for tracking during the reading,...
5235583 Optical scanning for record carriers adapted for reading with differing wavelengths  
A device in which a radiation source generates a radiation beam of a first wavelength. The scanning spot 7 generated by this radiation beam follows the centerline 13 of a track 8 to be scanned on a...
5235576 Optical disc apparatus  
An optical disc apparatus for use with an optical disc including on its tracks pairs of servo pattern areas to be recorded with an address pit pattern by using data patterns, each of which...
5233583 Tracking and reading system for an optical medium and medium for use therewith  
An optical disk includes a spiraling guide track embedded in a surface of the disk on either side of which is positioned a different information track. Apparatus for both tracking and reading the...
5231617 Optical information recording and reproducing apparatus and method of recording and reproducing information in an optical disk unit  
The present invention provides a large-capacity stack type optical disk unit capable of information recording and reproducing operation at a high speed and an optical information recording and...
5231618 Optical disc system  
An optical disc system is provided with a focusing error signal generator for detecting any focusing error from light reflected by an optical disc and outputting a focusing error signal; a driver...
5222057 Tracking servo method used in an optical disk drive unit  
A tracking servo method in an optical disk drive unit has the steps of providing a signal in accordance with a different in voltage level between two signals respectively reproduced from a pair of...
5218589 Defect detecting method  
In a method for detecting a defect in a prepit as a sampling object formed on a recording face of an information recording medium in an optical or magnetooptic disk drive unit, an optical or...
5218590 Optical disk apparatus having improved recording capacity  
An optical disk apparatus comprises an information generating circuit for inserting a predetermined number of resync codes in information to be recorded to generate record information, an optical...
5216646 Tracking system in recording/reproducing apparatus  
The present invention generally relates to optical recording/reproducing apparatus, and relates particularly to a tracking system therefor. Tracking pit rows are provided on opposite sides of an...
5214629 Optical disc having a high-speed access capability and reading apparatus therefor  
An optical disc for a sample servo type optical disc system. Servo areas disposed periodically on each of tracks of the optical disc are sequentially offset relative to those on the adjacent tracks...
5214635 Erasable optical disk and optical information recording/reproduction apparatus  
This invention provides an erasable optical disk, on which information is recorded and reproduced repeatedly through the irradiation of laser beams, and an optical information...
5212674 Optical high density data reproducing apparatus using interference techniques  
A laser beam emitted from a laser diode 12 is converted to parallel beams through a collimator lens 14. The beams pass through a stop 15, a polarizing beam splitter 16 and a λ/4 plate 18. The...
5210731 Information processing apparatus with missing pulse detection and correction  
An apparatus is provided for a disc-shaped information recording medium having a plurality of information recording tracks formed thereon with substantially equal distances therebetween in the...
5206847 Information recording disk, and information recording/reproducing method and apparatus utilizing the same  
There is disclosed an information recording disk, and a method and apparatus for information recording and reproduction, enabling secure tracking and full utilization of the recording capacity. For...
5202878 Optical recording and reproducing method and apparatus for the same  
According to the present invention, recording laser beam is shot from a semiconductor laser to form a mark set which comprises a pair of marks on the track of an optical recording medium in the...
5193081 Track-accessing controller for optical disks  
Disclosed is an optical disk apparatus applied to a data writing/reproducing operation of a sample-servo formatted optical disk having a clock pit and two wobbled pits in each of servo regions. A...
5191568 Disc drive apparatus with tracking control based on multiple reference tracks and with automatic seek time adjustment  
The present invention provides a disc drive apparatus having an improved tracking control and seek time adjustment. The head tracking error distribution along the disc radius is determined with...
5185730 Method for reading data from optical disk  
A method for writing data to and reading data from an optical disk that has address information written on its land between grooves or in its pregrooves. Because data is written to and read from...
5179268 Apparatus for detecting inclination of an optical card  
The present invention relates to an optical card reader that detects any relative inclination of the card by measuring the relative motion of the optical tracks themselves. The optical card reader...
5175725 Optical disk arrangement with closed contours whose entire extent represents information  
The present invention concerns an arrangement for reading an optically readable light reflective carrier on which data is stored in the form of diffractive elements which are deviations from a...
5166914 Data recording/reproducing apparatus with two-dimensional equalizer for crosstalk cancellation  
An equalizer apparatus is applied to a DBF disk recording medium in which a sampling clock is reproduced from clock pits recorded on the disk recording medium. A fixed coefficient equalizer...
5166915 Process for track jumping  
An arrangement for track skipping in a track control circuit with an optical scanner, in which two light beams reflected from an information medium, strike each onto a separate photodetector. The...
5166921 Optical disk carrying tracking information in multiple formats and apparatus for analyzing same  
An optical disk for information interchange having two distinct areas, one of which is comparatively wider than the other, each of the areas having a different tracking information format, so that...
5161136 Servo error detecting method of an optical disc system  
An optical disc system includes an optical disc which is formatted to store data in sectors. A tracking error signal is monitored and if the tracking error signal exceeds a predetermined threshold...
5155715 Reproducing apparatus  
A reproducing apparatus for reproducing information from recording elements formed with very small pits on a planar surface. The reproducing apparatus includes a probing unit positioned at a very...
5153863 Apparatus for optically recording and reproducing information  
An apparatus for optically recording and reproducing information in and from an optical information recording medium having a guide track. The apparatus uses an optical head having a diffraction...
5148422 Optical recording medium having a data recording track with offset data storing regions  
An optical recording medium for storing optically readable data includes at least one preformed recording track of predetermined width and extending in a predetermined recording direction, the...
5144608 Apparatus for recording and reproducing information on and from a recording medium having a reference position mark  
Disclosed is an information recording-reproducing apparatus including a light source for emitting a light beam, a lens device for imaging the light beam from the light source on an optical...
5140571 Disk drive apparatus with intermittently operated servo signal processor for low power consumption  
A disk drive apparatus which consumes less power to control the movement of a head on the basis of servo signals which are intermittently reproduced from a disk-like recording medium has a servo...
5138594 Reducing amplitude variations of optical disk readback signals and increasing reliability of track-crossing counts  
An optical disk recorder includes disk reflectance calibration means for measuring variations in disk reflectance over the recording area of the disk. Correction factors based on measured...
5136564 Pit pattern detecting apparatus and method  
A recording and/or reproducing apparatus includes a detection unit for detecting the presence of a tracking error detection pit pattern or a sector mark in a signal reproduced by an optical head...
5134601 Optical disk sector servo patterns  
Easily-fabricated, high track density, size-tolerant and efficient sector servo patterns are provided for optical disks. Easily-fabricated and efficient codes are provided for use with sector...
5132952 System for reproducing pulse time modulated wave forms stored along a diffractive track  
The present invention concerns an arrangement for reading an optically readable light reflective carrier on which data is stored in the form of diffractive elements which are deviations from a...
5132953 Multi-beam optical recording/reproducing apparatus for recording/reproducing on a medium having a recording flat part with a guide groove on each side  
An optical recording/reproducing apparatus wherein a main beam is converged and projected onto a flat part between tracking guide groove parts adjacent to each other in an optical recording medium...
5128916 Optical disc with alternating servo patterns and driving apparatus therefor  
An optical disc having a plurality of information tracks, each information track having a servo field including a pair of wobbled pits and a clock pit. The distance between one of the wobbled pits...
Matches 351 - 400 out of 540 < 1 2 3 4 5 6 7 8 9 10 11 >