Abstract: A method of automatically controlling bandwidth of a waveform equalizer in a DVD (Digital Video Disc) reproducing apparatus. The DVD reproducing apparatus includes an RF amplifier having the waveform equalizer of which a bandwidth is determined by a bandwidth control signal, and a digital signal processor for demodulating an EFM signal equalized by the RF amplifier. A system controller of the DVD apparatus checks an error cycle of an error signal received from the digital signal processor for a predetermined count cycle, while varying the bandwidth control signal step by step, so as to calculate an error rate according to the bandwidth control signal. Thereafter, the DVD apparatus outputs the bandwidth control signal having a minimum error rate out of the calculated error rates to the RF amplifier, thereby minimizing an error rate during data reproduction.

Abstract: A method, circuit and system for selectively and adaptively effecting conditioning of selected samples of a read signal in storage technologies. A circuit embodying the present invention includes sample logic, arithmetic logic and conditioning logic. The sample logic receives samples and provides a main sample and one or more selected neighbor samples. The arithmetic logic compares the main sample to the neighbor samples toward determining satisfaction of selected conditioning criteria. If the selected conditioning criteria are satisfied, the conditioning logic selectively and adaptively effects level conditioning as to the main sample. Further, the level conditioning is combined with a rule compliance system to insure the read data is following the protocol of the data coding format being used.

Abstract: Disclosed is an optical disk barcode forming method wherein, as information to be barcoded, position information for piracy prevention, which is a form of ID, is coded as a barcode and is recorded by laser trimming on a reflective film in a PCA area of an optical disk. When playing back the thus manufactured optical disk on a reproduction apparatus, the barcode data can be played back using the same optical pickup.

Abstract: The present invention provides an optical disc recording method and an optical disc recording apparatus for an optical disc of a high-density recording whose master can be subjected cutting with a high yield. The present invention also provides an optical disc access method and an optical disc apparatus capable of a high-density recording as well as an easy access. An address signal generating circuit 5 generates an address signal indicating an address data as a code having a minimum run length longer than a minimum run length of a modulated code based on a predetermined modulation rule of a user data recorded/reproduced via a recording/reproduction area. The address signal is recorded by an optical head 4 in a reproduction-dedicated area of a master disc 1.

Abstract: An information recording apparatus includes: a unit for applying a predetermined processing to record information divided into error correction units and generating processed record information including a plurality of record units; and a unit for recording the processed record information on an information record medium; a unit for recording, after the recording of the processed record information, predetermined dummy information of an information amount corresponding for the plurality of record units, on the information record medium, subsequent to the processed record information recorded.

Abstract: An information data recording/reproducing method correctly reproduces information data from a recording disc on which high density recording is performed through implementation of an increased linear density and a narrower track pitch. Each of recording data recorded at each of (m×n) recording points existing on n adjacent recording track (n is a natural number equal to or larger than two) including a target recording point and existing on m adjacent disc radial lines (m is a natural number equal to or larger than two) including the target recording point is subtracted from information data to derive a subtraction result. A residual operation is performed on the subtraction result to derive a residue value which is recorded at the target recording point. Recorded information is simultaneously read from (m×n) recording points existing on n adjacent recording tracks and existing on m adjacent disc radial lines to produce a read signal.

Abstract: A servo circuit performs tracking control such that the center of scanning is positioned at the center between the track from which data is reproduced and the track immediately before. Then, the beam spot scans the track from which data is to be reproduced and the immediately preceding track at the same time, and a reproduction signal made by inter-code interference between these two tracks is output. A precoding circuit performs a subtractive calculation on first data to be stored on a first track respective to second data stored on a precedent adjacent track to derive actual data to be stored on the first track and to compensate for the second data. In this way, pits or marks are formed such that inter-code interference is canceled during reproduction.

Abstract: An equalizer used for an optical reproducing apparatus performs an optimal equalizing operation in accordance with the spatial frequency without needing an electrical equalizer. The optical reproducing apparatus reproduces the reproducing data in the following manner. A detector is provided for receiving reflected light from a disc. The detector is divided into a plurality of light receiving areas by a line perpendicular to the light receiving direction corresponding to the disc track direction. Then, calculations are made on the outputs from the respective light receiving areas to specifically correct the spatial frequency characteristics. The calculated signal is then decoded.