| 摘要 |
PROBLEM TO BE SOLVED: To record/reproduce a precise signal without disturbing thinning and increasing a cost by providing a projection part for suppressing stray light in an optical system in the inside of a slide base. SOLUTION: The projection part 18 projecting to an inner surface side, that is, to an optical path side of a prescribed position of a dust cover 17 covering an optical system housing part is provided. This projection part 18 is formed by embossing with a press in the manufacturing process of the dust cover 17, and is placed on the central part of the optical system, that is, on a middle point between a semiconductor laser 8 and a prism mirror 12. Further, the projection part 19 is provided on the position of the slide base 2 corresponding to the projection part 18. This projection part 19 is formed integrally with the slide base 2 not to increase a cost. When a laser beam passes through between these projection parts 18 and 19, the useless diffusive light of the maser beam is cut by the projection parts, and the stray light is suppressed effectively, and the precise signal is recorded/reproduced. |
