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:
Jun. 15, 2010
Filed:
Nov. 23, 2004
Hideaki Hirai, Kanagawa, JP;
Tetsuya Ogata, Kanagawa, JP;
Hideaki Hirai, Kanagawa, JP;
Tetsuya Ogata, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
An optical system has an objective lens condensing a light beam from the light source on a recording layer selected from the plurality of recording layers of the optical disk, and leading a returning light beam reflected by the selected recording layer to a predetermined position; an aberration detecting part detecting a physical amount relative to spherical aberration based on an output signal of the photodetector; an aberration correcting part correcting the spherical aberration based on the physical amount; and a processing device carrying out at least the information reproduction o from among information recording, information reproduction and information deletion with the use of the output signal of the photodetector.