Patent ID: 7773833
Filing Date: 2010-08-10
Classification: G02F

Abstract:
1. An optical modulation device comprising: an optical modulation unit in which first and second sub-Mach-Zehnder optical waveguides are formed in two arms of a main Mach-Zehnder optical waveguide supplied with a beam having a frequency f a division unit which divides the output beam of the optical modulation unit into two beams; a filter unit which extracts the component of frequency f a first optical detector which measures a beam reception power of the filtered beam having the component of frequency f a second optical detector which measures a beam reception power of the other divided beam having the components of frequencies f wherein in the optical modulation unit, the first and second phase difference adjusting members are controlled so that the beam reception power measured by the first optical detector becomes a minimum value and the beam reception power measured by the second optical detector becomes a maximum value.