| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head device capable of preventing the generation of stray light transmitted or reflected through/on a transparent cylindrical part and appearing on an optical path even in the case of using an optical element provided with an element body in the transparent cylindrical part. <P>SOLUTION: In the optical head device, a diffraction element 6 is provided with a diffraction grating forming surface 69 formed in a transparent cylindrical holder part 60. Since an incident side end face 63 in the diffraction grating 6 is a rough surface on which fine ruggedness 630 is formed, laser light passed through the diffraction grating forming surface 69 at a large angle from an optical axis L is not reflected on an inner peripheral surface 62. Thereby stray light does not appear on the optical path to an optical recording disk. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
