The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 2007
Filed:
Jan. 31, 2005
Satoshi Yamashita, Kawasaki, JP;
Satoshi Yamashita, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A signal detection sections detect the light intensity modulated by the phase pits as ROM signals from the return lights of an optical storage medium that has phase pits and a recording layer to simultaneously regenerate data in the ROM and RAM, and detect the RAM signals where the return lights were modulated by the recording film. A feedback circuit reduces the cross-talk of the phase pits of the RAM signals of the recording film by feeding back the ROM signals to the laser drive current of the laser element, and a circuit for adjusting the feedback circuit so as to present a constant cross-talk suppression effect regardless the temperature change of the laser element. Since the feedback gain is changed by changing the laser temperature, an RF feedback gain, with which MO signals are not deteriorated by the change of the laser temperature, can be set.