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:
Dec. 09, 2014
Filed:
May. 14, 2012
Kouji Takeguchi, Kanagawa, JP;
Shigehiro Takashima, Saitama, JP;
Taichi Kogure, Kanagawa, JP;
Hirofumi Nakagawa, Kouza-gun, JP;
Saki Narisawa, Yokohama, JP;
Kouji Takeguchi, Kanagawa, JP;
Shigehiro Takashima, Saitama, JP;
Taichi Kogure, Kanagawa, JP;
Hirofumi Nakagawa, Kouza-gun, JP;
Saki Narisawa, Yokohama, JP;
Oclaro Japan, Inc., Kanagawa, JP;
Abstract
The I phase modulator modulates a phase based on the bias voltage in which a first modulation signal and a first pilot signal are inherent and the Q phase modulator modulates a phase based on the bias voltage in which a second pilot signal different from the first pilot signal and a second modulation signal are inherent. A time-average power synchronous detection unit detects an optical power at a timing at which the positivity and negativity of the voltages of both pilot signals become the same, and an optical power when the positivity and negativity of the voltages of both pilot signals are opposite. The bias voltage control unit controls the bias voltage so that the difference between both the optical powers becomes small based on the detection result of the time-average power synchronous detection unit.