| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical modulator adopting a control circuit of bias voltage of an optical modulator, which is inexpensive, applicable in a wide range and hardly influenced by change of optical modulation waveform. <P>SOLUTION: In the optical modulator 100 which applies CSRZ optical modulation to emitted light from a light source 101, the controlled light input from a controlled light input path 105 is input in an LN-MZ optical modulator 102 having progress wave type modulation electrode from the direction opposite to that of a signal light and average light intensity is detected by a photodetector 108. The bias voltage Vb is generated so that the optical intensity is minimized, and impressed to a bias input terminal 111 to perform automatic bias stabilization control. <P>COPYRIGHT: (C)2007,JPO&INPIT |
