Patents Assigned to Opto-Electronics & Systems Laboratories
  • Holographic optical element for optical disk pickup head
    Patent number: 5523993
    Abstract: A pickup head for use in optical disk systems such as compact disk players or CD-ROM computer memory includes a holographic optical element that has two decision regions that greatly simplify the design of the pickup head. The two decision regions diffract light that encounters the holographic optical element in two different directions, respectively. The amount of light power incident upon each decision region is utilized to determine a focus error signal and to interpret information stored on the compact or optical disk.
    Type: Grant
    Filed: May 17, 1995
    Date of Patent: June 4, 1996
    Assignee: Opto-Electronics & Systems Laboratories
    Inventor: Mark O. Freeman