Patents Assigned to Dsutsche Thomson-Brandt GmbH
  • Patent number: 5923626
    Abstract: The present invention to provides for information carriers of different storage densities, a recording and/or playback device which is compatible or can be used for different optical information carriers despite a functional relationship which to be satisfied between the size of the information memory location or pit size and the size of the light spot, without changing the wavelength of the laser used or changing the numerical aperture of the objective lens. In order to operate optical information carriers of different storage densities, use is made of an optical system which has a wavelength and numerical aperture matched to the highest storage density, provides a plurality of secondary beams matched to the respective track width, and has a number of secondary beam detector pairs which corresponds to the number of different information carriers.
    Type: Grant
    Filed: March 27, 1996
    Date of Patent: July 13, 1999
    Assignee: Dsutsche Thomson-Brandt GmbH
    Inventor: Hartmut Richter