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:
Nov. 20, 2001
Filed:
Sep. 18, 1998
Takuya Tanaka, Tokyo, JP;
Hiroshi Takahashi, Tokyo, JP;
Akimasa Kaneko, Tokyo, JP;
Akira Himeno, Tokyo, JP;
Yasuyuki Inoue, Tokyo, JP;
Nippon Telegraph & Telephone Corporation, Tokyo, JP;
Abstract
A frequency stabilized laser using an integrated external cavity, comprising a semiconductor laser diode and an optical waveguide installed on the same substrate, and having an optically induced grating formed in the optical waveguide suppresses mode hopping due to a temperature change to stabilize the oscillation frequencies of the laser. A material having a refractive index temperature coefficient opposite in sign to the refractive index temperature coefficient of the semiconductor laser diode is installed on that portion of the optical waveguide between the semiconductor laser diode and the optically induced grating which has been formed by removing an upper cladding and a core, or removing the upper cladding, the core, and a lower cladding.