| 摘要 |
<P>PROBLEM TO BE SOLVED: To precisely and smoothly perform focusing of a lens holder. <P>SOLUTION: A lower part of a guide shaft 3 is press fitted into a shaft hole 2 penetrating a base main part 1a of an act base 1 and erection plates 1b, 1c are erected from both edges at the front and rear of the base main part 1a. The upper surfaces of the respective erection plates 1b, 1c are formed as cover placing surfaces 4, and the upper surfaces 3a of the guide shaft 3 are formed flush with a horizontal level S with respect to each placing surface 4. A lens holder 10 with the objective lens OL is movably fitted to the guide shaft 3, and an act cover 15 made of a synthetic resin placed on each cover placing surface 4 is locked to the act base 1. A stopper 21 having a diameter h2 larger than that of the guide shaft 3, and a prescribed height t so as to face the upper surface 3a of the guide shaft 3 is integrally projected on the lower surface of the act cover 15. The stopper 21 is brought into contact with the upper surface 3a of the guide shaft 3, thereby elastically deforming the act cover 15 into a circular arc shape. <P>COPYRIGHT: (C)2009,JPO&INPIT |
