| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent occurrence of a noise component and to reduce a light quantity loss by reducing incidence of stray light which interfere with light returned to light receiving parts from a recording layer performing recording and reproduction of an optical disk. <P>SOLUTION: The optical pickup 7 for recording and/or reproducing information to/from the optical disk having one or a plurality of recording layers in an optical beam incident direction is provided with: a light source 31 emitting the optical beam having a prescribed wavelength; a diffraction element 32 diffracting and dividing the optical beam emitted from the light source 31 into at least two optical beams; an objective lens 33 condensing at least the two optical beams divided by the diffraction element 32 on recording layers of the optical disk; and an optical detector 34 having the light receiving parts 34a, 34b and 34c receiving returning light from the optical disk. The diffraction element 32 has a diffraction part having different diffraction structures and performing diffraction in different directions or a transmission part preventing diffraction provided in a center region of a region on the diffraction element corresponding to an incident pupil of the objective lens 33. <P>COPYRIGHT: (C)2008,JPO&INPIT |
