OPTICAL PICKUP AND OPTICAL PICKUP FOR PHASE TRANSITION TYPE OPTICAL DISK

摘要

PROBLEM TO BE SOLVED: To practically prevent the deterioration of optical characteristic of an optical pickup due to the generation of aberration in a cover member by non-rotatably providing the cover member to a housing member at the time of the volume change of a joining member. SOLUTION: A joining member 18 is mounted inside a cap 15. It is preferable to machine the joining member 18 in a shape lining along the aperture 15a of the cap 15 in order to facilitate the positioning of a cover member 16 to the cap 15. The cover member 16 is arranged on the upper surface of the joining member 18. By this constitution, since the positioning of the cover member 16 to the cap 15 and the joining member 18 is easily and exactly performed only by dropping it on the cap 15, the inclination of the cover member 16 is prevented.