Patent ID: 7936996
Filing Date: 2011-05-03
Classification: G02F,H04B

Abstract:
1. An optical modulator comprising: a first sub Mach-Zehnder waveguide (MZ a second sub Mach-Zehnder waveguide (MZ a main Mach-Zehnder waveguide (MZ a first electrode (electrode A) ( a second electrode (electrode B) ( a main Mach-Zehnder electrode (electrode C) ( a signal source ( a first bias adjusting means for adjusting bias voltage, the bias voltage being applied to the electrode A and the electrode B, the bias voltage being adjusted so as to maximize an intensity of the optical signal outputted from the main Mach-Zehnder waveguide; and a second bias adjusting means for adjusting bias voltage, the bias voltage being applied to the electrode C, the bias voltage being adjusted so that, when the intensity of the optical signal is represented by Max, an intensity of the optical signal is in between 40% to 60%, both inclusive, of the Max, while the bias voltage applied to the electrode A and the electrode B is kept to be the same level as the one obtained in the first bias adjusting means.