Patent ID: 8259552
Filing Date: 2012-09-04
Classification: G11B

Abstract:
1. An optical pickup apparatus comprising: a first laser unit including a first laser light source configured to emit a laser light of a first wavelength; and a second laser unit including second and third laser light sources configured to respectively emit laser lights of second and third wavelengths different from the first wavelength and different from each other, the first laser unit and the second laser unit being respectively disposed on a reflection surface side and a transmitting surface side of a first beam splitter, or, in reverse, on the transmitting surface side and the reflection surface side of the beam splitter, laser lights of the first, second, and third wavelengths, which are selectively emitted from the respective laser light sources of the first laser unit and the second laser unit, being guided onto a common optical path through the first beam splitter and guided to the respective sorts of optical recording mediums compatible with the laser lights, a diffraction grating being disposed on the common optical path, each of the laser lights of the first, second, and third wavelengths being divided by the diffraction grating into a main beam as well as preceding and subsequent sub-beams at the front and the back of the main beam, a second beam splitter being disposed on the upstream side of the diffraction grating, which is disposed on the common optical path, on a return path of each of the laser lights reflected and returned by the optical recording medium, each of the laser lights of the first, second, and third wavelengths returned from the optical recording medium through the second beam splitter being branched from the optical path on which the diffraction grating disposed and being received by a photodetector, wherein