Optical pickup system

Abstract

An optical pickup system capable of recording/reading out information on/from a mini disc or magneto-optical disc includes a polarized beam splitter (PBS) for fully reflecting beams of S-wave component from a laser diode or reflected from the disc while partially reflecting and partially transmitting beams of P-wave component, a reflection mirror placed between the PBS and disc for reflecting the beams transmitted through the PBS toward the disc while reflecting the beams reflected from the disc toward the PBS, a first photodetector having plural split areas for detecting a focus error and a tracking error according to the beams focusing on respective split areas, a hologram element for allowing three beams from a grating to be incident to the PBS or diffracting the beams of P-wave component transmitted through the PBS to focus the diffracted beams on the first photodetector, a second photodetector having six split areas for detecting the information recorded on the disc according to the beams focusing on respective split areas thereof, and a Wollaston prism placed between the PBS and second photodetector for separating mixed beams of P-wave and S-wave components from the PBS to allow the separated beams to be incident to the second photodetector, thereby decreasing the number of optical elements to improve readout speed of the information on the disc and simplifying the structure of the optical pickup system to reduce manufacturing cost.