Patent ID: 7558179
Filing Date: 2009-07-07
Classification: G11B

Abstract:
1. An optical pickup in an optical device compatible with first and second recording media having different formats, the optical pickup comprising: a light device module to selectively emit first and second light beams corresponding to the respective first and second recording media, said light device module to selectively emit the first and second light beams according to which one of the first and second recording media is received in the optical device; an objective lens disposed on a common optical path of the first and second light beams to focus the selectively emitted first and second light beams on the respective first and second recording media, the objective lens having a surface with at least one region having a different aspheric curvature from an aspheric curvature of another section of the surface such that the first and second light beams are focused on the respective first and second recording media; a photodetector to receive the first and second light beams reflected from the respective first and second recording media, and to detect a signal from the received first and second light beams; an optical path changing unit to selectively direct the first and second light beams reflected from the respective first and second recording media; and a light coupler to receive the first and second light beams from the light device module incident at different angles on a surface, and to transmit and/or diffract portions of the received first and second light beams along the common optical path, the light coupler being disposed between the light device module and the optical path changing unit.