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. 17, 1989
Filed:
Jun. 23, 1988
Applicant:
Inventors:
Katsuyuki Utaka, Musashino, JP;
Kazuo Sakai, Tokyo, JP;
Yuichi Matsushima, Tanashi, JP;
Shigeyuki Akiba, Tokyo, JP;
Assignee:
Kokusai Denshin Denwa Kabushiki Kaisha, Tokyo, JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
350 9619 ; 350 9613 ; 350 9614 ;
Abstract
A variable-waveguide optical branching filter is disclosed, in which a diffraction grating is formed in the cross region of two crossing waveguides, only light of a particular wavelength which is determined by the period of the diffraction grating is branched to a desired one of the waveguides, and the refractive index of the cross region is changed by control of a voltage or a current, or by way of irradiation with light, thereby changing the wavelength of light to be branched.