| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily control a bias voltage even in a band of >=10 GHz of a driving signal, and to prevent an optical output signal from being deteriorated in quality due to deterioration in waveform. SOLUTION: This optical transmitter is provided with a Mach-Zehnder type light modulator 2, a light source 1 for inputting an optical signal of continuous light to the Mach-Zehnder type light modulator 2, a branching filter 3 for taking out a part of the output optical signal, an optical spectrum monitor 4 for monitoring the optical spectrum of the taken-out output optical signal, an error signal generating circuit 11 for generating an error signal presenting a bias voltage error based on this monitoring result, and a bias voltage control circuit 5 for applying a bias voltage added with this error signal to the Mach-Zehnder type light modulator 2.</p> |
