Patent ID: 8145017

Claim:
An optical module comprising: a waveguide unit including an input waveguide, a circular waveguide, an output waveguide, and a branch waveguide branched from an input terminal of the input waveguide, the input waveguide, the circular waveguide, and the output waveguide forming a wavelength filter having a ring resonator structure; a semiconductor laser mounted on said waveguide unit and connected to the input terminal of the input waveguide; a semiconductor Mach-Zehnder modulator mounted on said waveguide unit and connected to an output terminal of the output waveguide; a first photodiode mounted on said waveguide unit and connected to an output terminal of the branch waveguide; a second photodiode mounted on said waveguide unit and connected to a through port of the input waveguide; a temperature adjustment unit which adjusts a temperature of said waveguide unit; a laser output controller which is connected to said first photodiode and said semiconductor laser to control an output from said semiconductor laser based on an output signal from said first photodiode; and a temperature adjustment controller which is connected to said second photodiode and said temperature adjustment unit to control a temperature adjustment operation of said temperature adjustment unit based on an output signal from said second photodiode.