| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress a deviation of an optical axis small with a simple mechanism, the deviation being caused by a light beam transmission-adjusting means for adjusting the optical power of a light beam which a light source emits. <P>SOLUTION: The light beam transmission-adjusting means is provided with; a holder which holds a first transmission element and a second transmission element which are orthogonal each other and on which a permanent magnet is mounted; and a base which holds a rotational shaft and on which an iron core for switching a position of the holder between first and second switching positions or holding it at the first or second position and a coil are mounted. In the first switching position at which a light beam passes through the first transmission element, the permanent magnet and the iron core are attracted and held in a state, in which the small projections of the holder contact the regulating surface of the base, and positioned, and in the second switching position at which a light beam passes through the second transmission element, the permanent magnet and the iron core are attracted and held in a state, in which the small projections of the holder contact the regulating surface of the base, and positioned. The position of holder is switched to the first and second switching positions by applying pulses to the coil. <P>COPYRIGHT: (C)2007,JPO&INPIT |
