| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup in which offset is not caused in a TE signal even during tracking with an objective lens when a two-layered disk is used. <P>SOLUTION: The optical pickup head includes a light source 1, a diffracting means 58 for creating a plurality of diffracted beams, z converging means for focusing the diffracted beams onto an optical storage medium, a beam branching means 52 for branching the plurality of beams 70a, 70b, 70c reflected by the optical storage medium 41, and an optical detecting means 32 for outputting a signal corresponding to the amount of light of the received beams, and when η<SB>m</SB>denotes diffraction efficiency of the 0 order diffracted light out of the diffracted light generated by the diffracting means 58 and η<SB>s</SB>denotes diffraction efficiency of the first or higher order diffracted light, the optical pickup head has relation of 10×η<SB>s</SB>≥η<SB>m</SB>. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
