Patent ID: 6876621
Filing Date: 2005-04-05
Classification: G11B

Abstract:
1. An optical pickup apparatus for reading/reproducing data on an optical recording medium, comprising: light sources configured to emit light beams of different wavelengths; a diffracting device configured to transmit the light beams emitted from the light sources and to diffract light beams reflected from the optical recording medium; an optical device having a reflecting portion and a transmitting portion, configured to reflect one part of the light beams emitted from the light sources to the diffracting device by the reflecting portion and to transmit other parts of the light beams emitted from the light sources to the optical recording medium by the transmitting portion, and to transmit the light beams reflected from the optical recording medium to the diffracting device by the transmitting portion; a photodetecting device configured to detect the light beams reflected from the optical recording medium through the optical device with reflecting portion and the diffracting device, for signal light detection; wherein the diffracting device includes plural diffracting portions, in which each of the diffracting portions corresponds to one of the different wavelengths, to diffract the respective parts of the light beams reflected by the reflecting portion of the optical device to the photodetecting device, so as to be detected on the photodetecting device for monitor light d of each of the light sources; and wherein the reflecting portion of the optical device includes plural reflecting portions arranged at positions corresponding to the light beams of the plural wavelengths, and the plural diffracting portions of the diffracting device are arranged at positions corresponding to the plural reflecting portions of the optical device respectively, and the light beams of different wavelengths reflected from the plural reflecting portions of the optical device are diffracted by the plural diffracting portions of the diffracting device to the photodetecting device for monitor light detection of each of the light sources.