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:
Feb. 13, 1990
Filed:
Jun. 24, 1988
Masao Kawachi, Mito, JP;
Norio Takato, Katsuta, JP;
Kaname Jinguji, Mito, JP;
Akio Sugita, Mito, JP;
Shin Sumida, Columbus, OH (US);
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
An integrated optical device includes a substrate; a single-mode optical waveguide having a cladding layer disposed on the substrate and a core portion embedded in the cladding layer for transmitting light therethrough; and a stress applying film disposed on a desired portion of the cladding layer for adjusting stress-induced birefringence of the single-mode optical waveguide by irreversibly changing the stress exerted on the core portion by a trimming technique. The integrated optical device can be manufactured by the steps of forming a cladding layer on a substrate; forming a single-mode optical waveguide having a core portion embedded in the cladding layer for transmitting light therethrough; and forming, on the cladding layer, a stress applying film for exerting a stress on the single-mode optical waveguide to irreversibly change the stress by trimming the film. The device exhibits a precisely adjusted birefringence and a desired polarization dependence or independence, and is effective for constructing an integrated optical device for optical communication, for optical sensing, or for optical signal processing, in which the polarization characteristics play an important role.