| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup in which a diffraction optical element is disposed in an optical path through which return light passes, with a technique capable of obtaining a proper TE signal stably. <P>SOLUTION: An optical pickup includes a diffraction optical element 17 for guiding reflection light (return light) from an optical disk to a light detection unit 19 in an optical path. The diffraction optical element 17 includes a substantially band-like diffraction region 171 with a direction substantially orthogonal to an arrangement direction of two push-pull signal component areas W as a longitudinal direction and through which a center part of the return light is transmitted. In the light detection unit 19, a main light receiving unit 191 for receiving light transmitted through the diffraction optical element 17 without being diffracted by the diffraction optical element 17, and sub light receiving units 192, 193 for receiving diffraction light diffracted by the substantially band-like diffraction region 171 are formed. A TE signal is generated by using signals output from the main light receiving unit 191 and the sub light receiving units 192, 193. <P>COPYRIGHT: (C)2012,JPO&INPIT |
