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:
Jun. 29, 2004
Filed:
Jan. 29, 2002
Yasuyuki Inoue, Tokyo, JP;
Yasuaki Hashizume, Tokyo, JP;
Yoshinori Hibino, Tokyo, JP;
Akio Sugita, Tokyo, JP;
Yasuhiro Hida, Tokyo, JP;
Hiroshi Takahashi, Tokyo, JP;
Other;
Abstract
A low-cost, high-reliability polarization-independent optical waveguide interferometer is proposed which does not bring about any additional job involved in the insertion of a half-wave plate or excess loss of light. In an optical multi/demultiplexer utilizing optical interference of light waves passing through a plurality of optical waveguides with different lengths, such as an AWG and a Mach-Zehnder interferometer, longitudinal integral values of birefringence values of the individual waveguides, which values are variable or invariable along the waveguides, are made equal for all waveguides 201 and 202. Thus, simply varying the waveguide width can implement polarization-independent operation, or on the contrary implement a polarization beam splitter. For example, the polarization-independent can be implemented by making the core widths, which are averaged in a longitudinal direction of a plurality of optical waveguides with different lengths, wider in a shorter optical waveguide, and narrower in a longer optical waveguide.