Patents by Inventor Sherlock Chu

Sherlock Chu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method for detecting data defect in optical recording medium
    Patent number: 7787337
    Abstract: A data signal includes a master signal generated by a master part of an optical pickup head in response to a light beam reflected from the optical recording medium and a side signal generated by a side part of the optical pickup head in response to the light beam reflected from the optical recording medium. A discriminating signal is obtained by subtracting the master signal from the side signal. Then, whether a data defect is existent in a data storage region of the optical recording medium can be determined according to the discriminating signal and optionally the side signal. When the data defect is determined existent, a servo tracking operation in the reading procedure is suspended.
    Type: Grant
    Filed: August 16, 2005
    Date of Patent: August 31, 2010
    Inventor: Sherlock Chu
  • Method and apparatus for retry calculation in an optical disk device
    Patent number: 7266069
    Abstract: A method for determining a maximum number of attempted retry operations when a read error occurs in an optical disk device. The method includes the steps of receiving an RF signal from a pickup of the optical disk device, detecting an envelope of the RF signal, asserting a defect signal when a level of the envelope is lower than a predetermined threshold, generating interrupt pulses during the assertion of the defect signal, and determining the maximum number of attempted retry operations using the interrupt pulses.
    Type: Grant
    Filed: February 6, 2004
    Date of Patent: September 4, 2007
    Assignee: Via Technologies, Inc.,
    Inventor: Sherlock Chu
  • Method for detecting data defect in optical recording medium
    Publication number: 20060039252
    Abstract: A data signal includes a master signal generated by a master part of an optical pickup head in response to a light beam reflected from the optical recording medium and a side signal generated by a side part of the optical pickup head in response to the light beam reflected from the optical recording medium. A discriminating signal is obtained by subtracting the master signal from the side signal. Then, whether a data defect is existent in a data storage region of the optical recording medium can be determined according to the discriminating signal and optionally the side signal. When the data defect is determined existent, a servo tracking operation in the reading procedure is suspended.
    Type: Application
    Filed: August 16, 2005
    Publication date: February 23, 2006
    Inventor: Sherlock Chu
  • Method and apparatus for retry calculation in an optical disk device
    Publication number: 20050188244
    Abstract: A method for determining a maximum number of attempted retry operations when a read error occurs in an optical disk device. The method includes the steps of receiving an RF signal from a pickup of the optical disk device, detecting an envelope of the RF signal, asserting a defect signal when a level of the envelope is lower than a predetermined threshold, generating interrupt pulses during the assertion of the defect signal, and determining the maximum number of attempted retry operations using the interrupt pulses.
    Type: Application
    Filed: February 6, 2004
    Publication date: August 25, 2005
    Inventor: Sherlock Chu