Patent ID: 6868055
Filing Date: 2005-03-15
Classification: G11B

Abstract:
1. An optical pickup, comprising: a first light source for generating a light beam having a first wavelength; a second light source for generating a light beam having a second wavelength different from the first wavelength; a lens system for focusing the two light beams on an optical disk; a photosensor for sensing reflection light beams from the optical disk; an optical path splitting element for splitting optical paths of the two reflection light beams having different wavelengths; and first and second hologram elements for respectively diffracting at least one of the two light beams of the different wavelengths which were split by the optical path splitting element, and guiding the thus diffracted light to the shared photosensor, wherein one of the first and second hologram elements is disposed in an optical path being an outward travel path between the light sources and the lens system, and the other is disposed in an optical path being a return travel path between the optical path splitting element and the photosensor through which only returning light travels.