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. 28, 2001
Filed:
Jul. 31, 1998
Kimihiro Kikuchi, Miyagi-ken, JP;
Yoshihiro Someno, Miyagi-ken, JP;
Atsunori Hattori, Miyagi-ken, JP;
Shoichi Kyoya, Miyagi-ken, JP;
Alps Electric Co., Ltd., Tokyo, JP;
Abstract
In an optical transmitting and receiving module, a transmitting light beam having a wavelength &lgr;,emitted from an light-emitting device passes through an optical demultiplexing filter and enters an optical fiber, and a receiving light beam emitted from an end face of the optical fiber is reflected from the optical demultiplexing filter and is incident on a light-receiving device. A cover for covering the front space of the optical demultiplexing filter is placed on a casing block, and a tongue piece serving as a returning-light preventing unit is formed on the cover. When a transmitting light beam emitted from the light-emitting device is reflected from the optical demultiplexing filter, the direction in which the reflected light advances is changed by the tongue piece so that the reflected light is not incident on the light-receiving device.