Patents by Inventor John D. Leigthon

John D. Leigthon 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).

  • Look ahead write precompensation
    Patent number: 6621648
    Abstract: A plurality of data bits are magnetically recorded on a medium (such as a magnetic disk in a disk drive system) by creating a write bubble region encroaching on the medium. The write bubble region has a magnetic polarity that is reversed in a pattern that corresponds to the values of the data bits being recorded on the medium. The timing of the reversing of the magnetic polarity of the write bubble region is adjusted by a precompensation system to ensure that the recorded data bits are evenly spaced on the medium. The timing adjustment is made by the precompensation system based on a state of at least one data bit previously recorded on the medium and on a state of at least one data bit to be subsequently recorded on the medium.
    Type: Grant
    Filed: April 30, 2001
    Date of Patent: September 16, 2003
    Assignee: Agere Systems Inc.
    Inventors: Carl F. Elliott, John D. Leigthon, Daniel J. Galaba, Thomas K. Adams, Sally A. Doherty