| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technique capable of obtaining a stable and proper TE signal in an optical pickup in which a diffraction optical element is arranged in a light path through which return light passes. <P>SOLUTION: An optical pickup 1 comprises a diffraction optical element 21 and a light detection part 23 which are commonly used at the time of use of a first light source 11 and at the time of use of a second light source 17. The diffraction optical element 21 includes a nearly belt-like diffraction region 211 which has a direction substantially perpendicular to the aligning direction of two push-pull signal component areas W as a longitudinal direction through which the center part of catoptric light reflected by an optical disc. In the light detection part 23, a main light-receiving part 231 for receiving light permeating the diffraction optical element 21 without being diffracted and sub-light-receiving parts 232 to 235 receiving diffraction light diffracted by the nearly belt-like diffraction region 211 are formed. The optical pickup 1 is provided such that a tracking error signal is generated by using signals output from the main light-receiving part 231 and the sub-light-receiving parts 232 to 235. <P>COPYRIGHT: (C)2012,JPO&INPIT |
