Patent ID: 7912380

Claim:
An optical receiver comprising: a photodiode for generating a photocurrent by receiving an optical input signal with a level corresponding to the photocurrent; a current mirror circuit for generating a mirrored current by receiving the photocurrent; a current-to-voltage converter to convert the mirrored current into a voltage signal; a first switch arranged between the current mirror circuit and the current-to-voltage converter; a resistor; a second switch inserted between the resistor and an output terminal of the current mirror circuit for outputting the mirrored current; a current source for generating an offset current for the current-to-voltage converter, the offset current being converted by the current-to-voltage converter independent of a state of the first switch; and a correction unit for subtracting a first voltage signal from a second voltage signal, wherein the first voltage signal is generated by the current-to-voltage converter when the first switch cuts the current-to-voltage converter from the current mirror circuit, and the second voltage signal is generated by the current-to-voltage converter when the first switch connects the current-to-voltage converter with the current-mirror circuit, wherein the first switch and the second switch complementary operate with each other.