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. 21, 1998
Filed:
May. 01, 1996
Seiji Manabe, Yamaga, JP;
Mikio Tomisaki, Chikushino, JP;
Shigeki Takeuchi, Yamaga, JP;
Tatsuya Hiwatashi, Kumamoto-ken, JP;
Kazuhisa Ide, Tamana, JP;
Toshihiro Koga, Kumamoto-ken, JP;
Makoto Okazaki, Kumamoto-ken, JP;
Kazuyuki Nakashima, Fukuoka, JP;
Sumio Tate, Kasuga, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In an optical pickup, an optical guide member is provided in an optical path of light from a light source, and has a plurality of inclined surfaces inclined with respect to a light beam emitted from the light source. A light-receiving element is provided for receiving light and for converting the received light into an electrical signal. The optical guide member and the light-receiving element are contained in a packaging member. The light beam from the light source is reflected by the plurality of inclined surfaces of the optical guide member, and then are directed to a recording medium. The reflected light from the recording medium is directed to the light-receiving element. At least one of dry air and inert gas such as nitrogen gas is charged in the interior of the packaging member at a pressure of 0.5 atm to 1.5 atm, thereby preventing the optical characteristics from being degraded.