| 摘要 |
<p>An optical head device for use in a disc player comprises a movable optical assembly (23; 71; 71 min ) in which an objective lens (11), first and second mirrors (44; 44 min , 45) and a light beam generating and detecting unit (43) are supported in common by a supporting member (22; 81; 81 min ), and a driving mechanism (20,21a,21b,24; 72,74) for moving the movable optical assembly (23; 71; 71 min ) in both a first direction along an optical axis of the objective lens (11) and a second direction perpendicular to the first direction, wherein, in the movable optical assembly (23; 71; 71 min ), a light beam generated in the light beam generating and detecting unit (43) is reflected twice by the first and second mirrors (44; 44 min , 45) to be changed in its traveling direction, and focused by the objective lens (11) at a position on the optical axis of the objective lens (11), and a light beam coming from the outside of the movable optical assembly (23; 71; 71 min ) is received by the objective lens (11) to pass therethrough to the second mirror (45), reflected twice by the second and first mirrors (44; 44 min , 45) to be changed in its traveling direction, and guided to a photodetector (51,52) contained in the light beam generating and detecting unit (43).</p> |
