| 摘要 |
<p>An optical semiconductor amplifier of the present invention comprises an input optical waveguide medium for feeding input light. A first optical branching circuit which is included a first optical coupler splits the input light into two. An optical semiconductor amplifier amplifies one of two light split by the first optical branching circuit. A first photodetector receives the other of the two light and generates a corresponding first electric signal. A second optical branching circuit which is included a second optical coupler splits the light amplified from the optical semiconductor amplifier into two. A second photodetector receives one of two light split by the second optical branching circuit, and generates a corresponding second electric signal. An output optical waveguide receives the other of the two light split by the second optical branching circuit. A feedback control circuit controls an injection current to the optical semiconductor amplifier in response to the first and second electric signals. <IMAGE></p> |
