| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical transmitter controlling an amplitude of a modulator driver without enlargement of a circuit scale. <P>SOLUTION: The optical transmitter is equipped with: an optical modulator containing a phase modulator (20) and a delay interferometer (30) for delay interference of a part of output light of the phase modulator; and a controller (60) for monitoring an output level of the delay interferometer and controlling an amplitude of the modulator driver based on the result of monitoring. The amplitude of a drive signal supplied to the phase modulator may be controlled so that the sum of a positive phase signal optical intensity and an opposite phase signal optical intensity of the delay interferometer becomes largest. A voltage supplied to the delay interferometer may be controlled so that a difference between a positive phase signal optical intensity and an opposite phase signal optical intensity of the delay interferometer becomes largest. <P>COPYRIGHT: (C)2011,JPO&INPIT |
