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. 24, 2007
Filed:
Mar. 21, 2006
Shinichi Hamaguchi, Hyogo, JP;
Naoki Nakanishi, Shiga, JP;
Tatsuya Nakamori, Kyoto, JP;
Naoto Shimada, Osaka, JP;
Shinichi Hamaguchi, Hyogo, JP;
Naoki Nakanishi, Shiga, JP;
Tatsuya Nakamori, Kyoto, JP;
Naoto Shimada, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An optical path coupling member aligns an optical axis directed to a light condensing member of the first wavelength light having a shortest wavelength with that of the third wavelength light having a longest wavelength. A diffraction element condenses +2nd order diffracted light of the first wavelength light and +1st order diffracted light of the second wavelength light and third wavelength light into a first photodetector, the −2nd order diffracted light of the first wavelength light and −1st order diffracted light of the third wavelength light into a second photodetector, and −1st order diffracted light of the remaining second wavelength light into a photodetector, using ±2nd order diffracted light of the first wavelength light and ±1st order diffracted light of the second wavelength light and third wavelength light as signal light from an optical information recording medium. Consequently, the overall size of the optical pickup apparatus is reduced.