| 摘要 |
PURPOSE:To decrease the generation amount of the crosstalk from an adjacent track, even in case an optical disk is bent due to deformation, dead weight, etc., by dividing a photodetector into plural photodetecting areas, and detecting an information signal from only the photodetecting area of a spot center part. CONSTITUTION:A reflected light from an optical disk 6 is converted to a parallel luminous flux again by an objective lens 5, and thereafter, reflected by a beam splitter 4, passes through a convex lens 7, and a cylindrical lens 8 and irradiated onto a photodetctor 9. Among luminous fluxes which are divided into three by a diffraction grating 3, + primary light and - primary light are irradiated to photodetecting areas of both sides of the photodetector 9, and '0' -order light is irradiated to the center of an 8-divided area of the center of the photodetector 9. An output signal of the photodetector 9 is recorded in the optical disk 6, and an information signal and a focusing error signal, and a tracking error signal are obtained. In such a way, even if a relative inclination is generated in the optical disk 6 and an optical pickup, the crosstalk contained in the information signal can be reduced. |
