Patent ID: 7821903
Filing Date: 2010-10-26
Classification: G11B

Abstract:
1. An optical pickup device comprising: a light source for outputting a laser beam of a predetermined wavelength; a photodetector for detecting an intensity of the laser beam outputted from the light source to control a power of the laser beam to be outputted from the light source; a polarization beam converter for converting the laser beam outputted from the light source into a circularly polarized laser beam; and a mirror for guiding part of the laser beam converted by the polarization beam converter to the photodetector, and guiding the remainder of the laser beam to an optical recording medium; wherein the mirror includes a partly transmitting mirror for transmitting the laser beam that has been converted into a circularly polarized laser beam by the polarization beam converter toward the photodetector, and reflecting the laser beam toward the optical recording medium, and the partly transmitting mirror has a characteristic that a transmittance of a P-polarized component in the laser beam is larger than a transmittance of an S-polarized component in the laser beam.