| 摘要 |
PURPOSE:To provide an optical reception circuit, which can accurately monitor an optical input level with a more simplified circuit, concerning the optical reception circuit using an avalanche photodiode. CONSTITUTION:An optical reception circuit provided with an avalanche photodiode 100 for converting input light to an electric current and outputting it is equipped with a PIN photodiode 300 for branching one part of input light to the avalanche photodiode 100, inputting the light, converting it to the current and outputting it, and the level of input light to the avalanche photodiode 100 is monitored by an output of the PIN photodiode 300. |
