| 摘要 |
<p>An optical pickup for reading information recorded on a recording surface (S2) of an optical information storage medium (DK) has a light beam source (1) for emitting a linear light beam, and an optical system (2,3) including an objective lens (4) for converging the linear light beam as a linear image on the recording surface and collecting and emitting a light beam reflected from the recording surface. A tilt control device (100) includes a parallel flat glass plate (11, 12,15,16,18) for refracting the reflected light beam from the optical system, a plurality of photodetector units each having a plurality of photosensitive surfaces (a) for photoelectrically converting the light beam applied thereto from the parallel flat glass plate into a plurality of respective detected signals (I), an error generator (6) for processing the detected signals from the photodetector units into a tilt error signal indicative of whether the linear light beam is applied perpendicularly to the recording surface, and an actuator (7) responsive to the tilt error signal for controlling the objective lens positionally with respect to the optical information storage medium to apply the linear light beam perpendicularly to the recording surface. <IMAGE></p> |
