Photodetector disposed on both sides of an objective lens for receiving +/- 1st order diffractive light

摘要

An optical pickup provided with a photodetector for detecting a tracking error signal includes a light source for radiating light; an objective lens disposed on an optical path between the light source and a disc which is an optical recording medium for focusing the light radiated from the light source on the optical disc; a diverter for diverting the optical path of reflected light disposed between the light source and the objective lens to prevent the light reflected from the disc from being reflected back to the light source; and a photodetector for receiving the light reflected from the disc and detecting a tracking error signal and a focusing error signal. The photodetector consists of a first photodetector having a plate divided into at least two pieces for detecting light passing through the optical-path diverter converter after being reflected from the disc; and a second photodetector disposed around the objective lens and moving together therewith, and having a plate divided into at least two pieces.