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. 07, 2021
Filed:
Mar. 19, 2019
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
NIPPON TELEGRAPH AND TELEPHONE CORPORATION, Tokyo, JP;
Abstract
An optical modulator according to embodiments includes a first MZI and a second MZI each including a first optical coupler that splits CW light into two, a second optical coupler that couples the CW light split by the first optical coupler and outputs the CW light, and a bias electrode that adjusts a phase of the CW light split by the first optical coupler, a third optical coupler that couples outputs of the first MZI and the second MZI with at a predetermined ratio and outputs the light, and a bias adjustment circuit that adjusts an output voltage of a bias power supply applied to a bias electrode so that an optical path length difference between the CW light beams split by the first optical coupler is a predetermined times a carrier wavelength under a condition that an output of a differential output amplifier is a zero level, in accordance with an operating mode of the own apparatus.