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:
Aug. 24, 2004
Filed:
Sep. 20, 2001
Takehiro Motegi, Saitama, JP;
Shinichi Takahashi, Saitama, JP;
Mitsutoshi Sugano, Saitama, JP;
Ko Ishii, Saitama, JP;
Yoshihiro Seita, Saitama, JP;
Makoto Kawamura, Saitama, JP;
Pioneer Corporation, Tokyo, JP;
Abstract
Laser beams h , h with different wavelengths emitted from semiconductor lasers are incident to an optical path joint prism and each of optical intensities of the laser beams h , h is detected by a photoelectric conversion element provided in an optical path integrated by the optical path joint prism on which a semi-transmission film HM is provided and APC control of each of light emission intensities of the semiconductor lasers is performed on a basis of each of detection results. As a result of this, the beam intensity of the laser beam h passing through the optical path joint prism to be applied to an information recording medium and the laser beam h reflecting the optical path joint prism to be applied to the information recording medium are controlled properly.