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:
Jan. 12, 2016
Filed:
Jan. 25, 2012
Takashi Saida, Atsugi, JP;
Yusuke Nasu, Atsugi, JP;
Takayuki Mizuno, Atsugi, JP;
Ryoichi Kasahara, Atsugi, JP;
Takashi Saida, Atsugi, JP;
Yusuke Nasu, Atsugi, JP;
Takayuki Mizuno, Atsugi, JP;
Ryoichi Kasahara, Atsugi, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
Provided is a waveguide-type polarization beam splitter in which deterioration of a polarization extinction ratio due to temperature change and wavelength change is suppressed. A groove is formed to extend across a pair of optical waveguide arms and two quarter wave plates are provided in the groove to extend respectively across the arms. Polarization axes of the quarter wave plates are orthogonal to each other. A first optical coupler which gives a phase difference of 0° or 180° between coupled or split light beams and a second optical coupler which gives a phase difference of 90° or −90° between coupled or split light beams are used in combination.