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:
Aug. 27, 2002
Filed:
Oct. 22, 1999
Hideki Nishimoto, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical information storage device for directing an incident light beam onto a recording medium having a recording surface composed of lands and grooves as tracks and detecting a reproduced signal from a reflected light beam from the recording medium. The optical information storage device includes a phase plate provided in an optical path of the reflected light beam so as to be tiltable between a first position where the phase plate gives to the reflected light beam a first phase compensation amount required for detection of signals from the lands and a second position where the phase plate gives to the reflected light beam a second phase compensation amount required for detection of signals from the grooves; and a drive mechanism for tilting the phase plate. Examples of the drive mechanism include a solenoid, DC motor, and voice coil motor.