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:
Nov. 10, 2009
Filed:
Jun. 17, 2005
Masahiro Saito, Kanagawa, JP;
Norio Fukasawa, Kanagawa, JP;
Kiyoshi Toyota, Tokyo, JP;
Junichi Suzuki, Kanagawa, JP;
Masahiro Saito, Kanagawa, JP;
Norio Fukasawa, Kanagawa, JP;
Kiyoshi Toyota, Tokyo, JP;
Junichi Suzuki, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
An optical pickup apparatus and an optical disc apparatus are adapted to raise the efficiency of utilization of the lasers of the apparatus for accurately detecting tracking errors by raising the intensity ratio of the beam of the 0-th order to the beams of the ±1st orders produced by splitting of the laser beam of the wavelength to be subjected to division by three. The optical pickup apparatus includes a light emitting section for emitting a first laser beam having wavelength λand a second laser beam having wavelength λdifferent from the wavelength λ