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. 13, 2009
Filed:
Sep. 10, 2004
Hiroshi Akiyama, Kanagawa, JP;
Hiroshi Akiyama, Kanagawa, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A method for adjusting an aberration is disclosed that adjusts the aberration existing in a light spot by using a control signal generated from a wobbling signal and a reproduction signal, and thereby maintaining an appropriate S/N ratio for both the wobbling signal and the reproduction signal even when astigmatism, spherical aberration, or other aberrations are present. In an optical pickup, by moving a collimator lens along a light path, a spherical aberration is generated on the light emitted from a light source, a reproduction signal (RF signal) is obtained from the light reflected from an optical disk, a wobbling signal is obtained from the light reflected from grooves on the optical disk, and the correction aberration is adjusted based on the RF signal and the wobbling signal.