| 摘要 |
PURPOSE:To reduce the influence of the noise of a photodetector and to attain a highly sensitive optical reception by setting an identification reference voltage in an identification circuit in accordance with an optical input level. CONSTITUTION:An optical receiver which amplifies the output signal of the photodetector 1 having an amplifying function through an amplifier 2 and which identifies it in the identification circuit so as to reproduce data is provided with an identification reference voltage control operator 6. It is inputted with a signal showing the size of the amplification factor of the photodetector 1 and a signal showing the size of the gain of the amplifier 2, and it generates the identification reference voltage of the identification circuit 4 which is optimum for reducing the influence of the noise of the photodetector 1 predicted from said signals. Even if the photodetecting level falls, the identification reference voltage is optimized, whereby identification errors can be reduced and therefore light signals can be received with high sensitivity. |
