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:
Mar. 27, 2012
Filed:
Oct. 01, 2009
Hiromasa Tanaka, Tokyo, JP;
Hiromasa Tanaka, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In an optical module, a waveguide unit has a wavelength filter having a ring resonator structure. A semiconductor laser is connected to the input terminal of an input waveguide. A semiconductor Mach-Zehnder modulator is connected to the output terminal of an output waveguide. A first photodiode is connected to the output terminal of a branch waveguide. A second photodiode is connected to the through port of the input waveguide. A temperature adjustment unit adjusts the temperature of the waveguide unit. A laser output controller is connected to the first photodiode and the semiconductor laser to control an output from the semiconductor laser based on an output signal from the first photodiode. A temperature adjustment controller is connected to the second photodiode and the temperature adjustment unit to control the temperature adjustment operation of the temperature adjustment unit based on an output signal from the second photodiode.