LIGHT RECEIVING MODULE

摘要

PURPOSE:To extend the dynamic range of a received optical signal by suppressing deterioration due to distortion caused at the time of photoelectric conversion of a photodetector and signal amplification after the photoelectric conversion when received optical signal power is increased in the light receiving module converting an optical signal into an electric signal. CONSTITUTION:An optical signal 102 made incident from an optical fiber 101 is converted into an electric signal by a photodetector in a light receiving section 103. A detection circuit 104 detects an average voltage drop caused in the photodetector at the time of photoelectric conversion. A control circuit 105 uses a difference between the average voltage drop detected by the detection circuit 104 and a reference voltage to provide an output of a control signal. Furthermore, a mount 106 receives an output signal from the control circuit 105 to change a relative position between the light made incident onto the light receiving section 103 and to control the light receiving power of the light receiving display section 103.