Patent ID: 8238393

Claim:
A multi-beam laser light-intensity control circuit, comprising: a plurality of laser diodes; a single light-receiving element configured to receive a laser beam emitted from each of the laser diodes and to output a current corresponding to a light intensity of the received laser beam; and an automatic power control circuit configured to automatically control output power of each of the laser diodes based on the current output from the light-receiving element, wherein the automatic power control circuit includes a current/voltage conversion unit configured to convert the current output from the light-receiving element into a voltage; a single error amplifying circuit provided for the laser diodes and configured to amplify a difference voltage between the voltage output from the current/voltage conversion unit and a predetermined reference voltage and to output the amplified difference voltage; storing circuits each configured to store the difference voltage output from the error amplifying circuit in association with a corresponding one of the laser diodes; and drive current generating units each configured to generate a drive current for driving the corresponding one of the laser diodes based on the difference voltage stored in a corresponding one of the storing circuits.