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. 29, 2002
Filed:
Jan. 07, 2000
Hirataka Ukai, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
An optical information storage device including a first photodetector for detecting a regenerative signal from reflected light from an optical recording medium, a second photodetector for detecting a tracking error signal and a focusing error signal from the reflected light, and a beam splitter for separating the reflected light into a first beam directed toward the first photodetector and a second beam directed toward the second photodetector. The optical information storage device further includes a phase compensating mechanism provided between the beam splitter and the first photodetector for compensating for a phase difference of the first beam, a Wollaston prism provided between the phase compensating mechanism and the first photodetector for separating the first beam into two beams having orthogonal polarization planes, and a polarization plane rotating mechanism for rotating the polarization plane of the first beam incident on the Wollaston prism.