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:
Jul. 21, 1998
Filed:
Feb. 08, 1996
Harukazu Miyamoto, Kodaira, JP;
Takeshi Shimano, Tokorozawa, JP;
Hisataka Sugiyama, Kodaira, JP;
Mariko Umeda, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
An optical disk device having a light source for emitting light, focusing optics for radiating and focusing the light onto an optical recording medium, a photo-detection system for photoelectrically transforming reflected light from the optical recording medium, a reproduction circuit for reproducing information recorded on the optical recording medium by using an electric signal from the photo-detection system, phase control optics for changing the phase of the reflected light, a readout control circuit for controlling the quantity of the phase change of the phase control optics, and a learning control circuit for calculating the optimum value of the phase change quantity by monitoring the output signal of the reproduction circuit while changing the quantity of the phase change by the readout control circuit. Thus, information can be reproduced from a recording medium having high recording density without crosstalk.