Photodetector-amplifier circuit and optical pickup device

摘要

The present invention provides a photodetector-amplifier circuit capable of eliminating an influence of noise due to stray light entering a non-selected photodetector to stably select and switch a photodetector. The photodetector-amplifier circuit of the present invention comprises photodetectors 12 and 13. The photodetector 12 is connected via a switch 16 between an inverting input terminal of an operational amplifier 11 and GND, and is also connected via a switch 18 to a voltage source Vcc. The photodetector 13 is connected via a switch 17 to the inverting input terminal of the operational amplifier 11 and GND, and is also connected via a switch 19 to the voltage source Vcc.