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:
Sep. 15, 1992
Filed:
Jul. 08, 1991
Yasuhisa Tanisawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In an optical waveguide device, a plurality of optical directional coupler switches are provided on a substrate, and light input and output terminals are also provided to be coupled to the optical directional coupler switches. Each of the optical directional coupler switches is provided with a pair of parallel waveguides. One of the optical directional coupler switches operates independently of the polarization of light having a first predetermined wavelength by defining a width of the parallel waveguides and a distance therebetween to be first predetermined values, and one of the optical directional coupler switches operates independently of the polarization of light having a second predetermined wavelength by defining a width of the parallel waveguides and a distance therebetween to be second predetermined values. The parallel waveguides of the first and second ones of the optical directional coupler switches are provided by diffusing films of the same thickness deposited in a predetermined pattern on the substrate thereinto by a predetermined diffusing condition.