| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical reception circuit wherein the optical signal is accurately received even if there exists a high bias light, with no additional electrostatic capacity at an input terminal of a preamplifier. SOLUTION: The optical reception circuit comprises a first adder 23 which adds a reverse phase signal ND to an output signal PKP of a first peak hold circuit 41, a second adder 24 which adds a normal phase signal D of a preamplifier 2 to an output signal PKN of a second peak hold circuit 42, and a differential amplifier 25 into which addition results Q and NQ are inputted. There are provided a data detection circuit 31 which detects that an optical input signal is inputted based on the change in the value of the reverse phase signal ND or normal phase signal D outputted from the preamplifier 2, and a reset circuit 32 which uses the signal at a rising part in an output signal DDET of the data detection circuit 31 to output a reset signal RES to at least the second peak hold circuit 42. |
