Patents by Inventor Johannes Hendrik Spruit

Johannes Hendrik Spruit 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 and device for recording an optical information carrier
    Patent number: 6751513
    Abstract: A method is described for recording an optical information carrier, in which a mark representing recorded data is written in the information carrier at different writing speeds by a sequence of radiation pulses The last pulse of a sequence is followed by a period of reduced radiation power, the duration of which is inversely proportional to the writing speed.
    Type: Grant
    Filed: October 16, 2000
    Date of Patent: June 15, 2004
    Assignee: Koninklijke Philips Electronics N.V
    Inventor: Johannes Hendrik Spruit
  • Method and device for recording an optical information carrier
    Patent number: 6205102
    Abstract: A recording layer of rewritable phase-change material is directly overwritten by a pulsing laser spot irradiating at a writing power level, then irradiating at a lower cool-down power level during a cool-down period, and then irradiating at an erasing level with a higher power than the cool-down level. The duration of the cool-down period depends on the spot size and/or on the linear velocity of the spot with respect to the recording layer.
    Type: Grant
    Filed: October 8, 1997
    Date of Patent: March 20, 2001
    Assignee: U.S. Philips Corporation
    Inventor: Johannes Hendrik Spruit