Pulse Forming By Adjusting Binary Signal Phase Or Shifting Binary Signal Pulse Patents (Class 369/59.12)
  • Publication number: 20020001275
    Abstract: An information recording method and an apparatus therefor, wherein a recording compensation controlling unit 1 receives data to be recorded and determines whether a pulse timing adjustment is to be performed or not, and instructs an APC 3 to adjust the timing thereby to advance the pulse start timing of laser light and/or to delay the pulse termination timing when the pulse timing adjustment is to be performed. The recording compensation controlling unit 1 determines the pulse timing adjustment corresponding to the presence or absence of a predetermined “space, record mark”, whereby the positional shift quantity of leading and trailing edges is reduced even for the marks having a fine dimension, and the jitter is reduced.
    Type: Application
    Filed: January 30, 2001
    Publication date: January 3, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Tsutomu Tanaka, Masakazu Taguchi, Takuya Kamimura
  • Publication number: 20010055258
    Abstract: An apparatus and method are disclosed for optimizing the writing of data to an optical disc to improve readback characteristics and minimize the effects of errors. An optimization circuit generates an optimized modulation signal which is used to modulate a writing beam of a laser beam recorder, the optimized modulation signal comprising a series of data symbols that correspond to resulting pits and lands on the optical disc. The optimization circuit optimizes the locations of pit and land transitions on the optical disc by individually adjusting leading and trailing edges of the data symbols, as well as amplitudes of the data symbols. In this manner, the particular length of each pit and land on the disc can be individually selected based on nominal symbol length, as well as other factors including radial and angular locations of the pits and lands on the disc.
    Type: Application
    Filed: August 21, 2001
    Publication date: December 27, 2001
    Applicant: DOUG CARSON & ASSOCIATES, INC.
    Inventors: Douglass Marshall Carson, James Maurice Colpitts
  • Publication number: 20010053115
    Abstract: An optical recording method for recording mark length-modulated information on a recording medium by using a plurality of recording mark lengths.
    Type: Application
    Filed: June 20, 2001
    Publication date: December 20, 2001
    Applicant: MITSUBISHI CHEMICAL CORPORATION
    Inventors: Natsuko Nobukuni, Michikazu Horie
  • Publication number: 20010046197
    Abstract: A system and method are disclosed for generating a transition in a laser control signal at a precise point in time. A write strategy processor is configured to input a sequence of data and to determine a transition in a laser control signal from the sequence of data. The transition is specified by a number of pulse clock units and a delay. A write pulse generator is configured to input the number of pulse clock units and the delay and to generate a transition by creating a signal having a transition at the time specified by the number of pulse clock units and delaying the transition by the specified delay.
    Type: Application
    Filed: June 7, 2001
    Publication date: November 29, 2001
    Inventors: Ian E. Harvey, Nugroho Suwito
  • Publication number: 20010038583
    Abstract: A method of recording data on a recording medium includes mapping the data to a set of write symbols wherein each write symbol represents more than one bit of the data. The set of write symbols is defined by defining a set of variable write parameters; generating a plurality of candidate write symbols that specify different values for the variable write parameters; generating a plurality of readout waveforms produced by the plurality of candidate write symbols; analyzing the readout waveforms to determine desired set of readout waveforms; and selecting selected ones of the plurality of candidate write symbols that correspond to the desired readout waveforms to be included in the set of write symbols. The data is written to the medium using the write symbols.
    Type: Application
    Filed: March 29, 2001
    Publication date: November 8, 2001
    Inventors: Naoyasu Miyagawa, Masud Mansuripur
  • Patent number: 6307823
    Abstract: Provided are an optical information medium, an optical information recording method and an optical information recording apparatus in which an accurate cross talk can be predicted with a simple structure in a recording mode such as CLV so that a disk having a cross talk reduced can be created.
    Type: Grant
    Filed: May 28, 1999
    Date of Patent: October 23, 2001
    Assignee: Sony Corporation
    Inventor: Seiji Kobayashi
  • Publication number: 20010028618
    Abstract: In a writing device for writing data at 1-time or higher recording rates, a first delay circuit capable of variably controlling a delay time in units of a relatively long time and a second delay circuit capable of variably controlling a delay time in units of a relatively short time are employed in a combined manner. A laser drive pulse can be controlled in the direction of the time base with high accuracy corresponding to any recording rates ranging from 1-time to higher, e.g., 8- or 12-time, speeds without using very large number stages of delay gates.
    Type: Application
    Filed: January 17, 2001
    Publication date: October 11, 2001
    Inventors: Munetoshi Moriichi, Mitsuyuki Bamba, Takashi Sasaki
  • Publication number: 20010026530
    Abstract: The present invention relates to an optical disk, an optical disk device, and an optical disk recording method. When it is applied to, for example, a compact disk. It attempts to reduce a jitter at the time of reproduction, and reproduce surely the recorded data. A change pattern of a modulation signal (S2) is detected, and the timing of a modulation signal (S1) is corrected according to this change pattern, to irradiate a laser beam L.
    Type: Application
    Filed: February 4, 1999
    Publication date: October 4, 2001
    Inventors: SEIJI KOBAYASHI, KOJI FUJIMIYA
  • Patent number: 6295259
    Abstract: To more precisely digitize a signal read from a data storage medium into a binary value to reduce the rate of occurrence of bit error in reproduction. A phase difference of the intersecttion between a signal read from a data storage medium and a slice signal is evaluated to select a probable time cell in which the intersection should be contained for more precisely digitizing the read signal into a binary value.
    Type: Grant
    Filed: May 20, 1999
    Date of Patent: September 25, 2001
    Assignee: International Business Machines Corporation
    Inventor: Toshio Kanai
  • Publication number: 20010008508
    Abstract: The present invention provides an exposure apparatus of an optical disc master plate for exposing a photoresist master plate and writing-in a DVD-R format, and a method of exposing an optical disc master plate. The exposure apparatus of the optical disc master plate can cause both the wobble signal and the land pre-pit signal to precisely synchronize with each other and to output the synchronized signals by use of a formatter. The formatter can facilitate the design of a separation element for electrically separating an analog circuit and a digital circuit from each other and a circumferential circuit thereof. The formatter of the optical disc exposing apparatus operates on the basis of the predetermined basic clock signal Fclk. The formatter is provided with a wobble signal generating circuit which generates a wobble signal and a land pre-pit signal generating circuit which operates on the basis of the same basic clock signal Fclk and generates a land pre-pit signal.
    Type: Application
    Filed: February 16, 2001
    Publication date: July 19, 2001
    Applicant: RICOH COMPANY, LTD.
    Inventor: Hisao Watanabe