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. 20, 1998
Filed:
Apr. 30, 1996
Taro Takekoshi, Suwa, JP;
Masatoshi Yonekubo, Suwa, JP;
Takashi Takeda, Suwa, JP;
Toshio Arimura, Suwa, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
A plurality of inclined planes (1419) are formed in the same substrate (1406) and a polarizing optical thin film is provided on these inclined planes. These inclined planes are filled with a transparent material so as to form a small sized and complexed polarizer. This polarizer is excellent in transmission ratio and in extinction ratio. With this polarizer, it is possible to detect a magneto-optical signal with a high signal-to-noise ratio. This polarizer is used as a cover of a package (1408) of an optical head in which a light receiving device (1410, 1411) and a light emitting device (1409) are contained in the form of a single piece. There is also provided an optical element capable of adjusting optical paths so that the optical length of a returning optical beam may be different from the optical length of a forward optical beam. With this optical element, it becomes possible to delete the initial offset in a focusing error signal, and thus adjustment process becomes unnecessary. With these arrangements, it is possible to achieve the size reduction, simplification, and improvement of performance associated with an optical head for use in a magneto-optical recording/reproducing device.