| 摘要 |
A thruhole 23 is provided with a movable member so that a light beam irradiated from an LED passes through the thruhole and is received by a photo detector for positional detection whereby the position of an objective lens relative to the light receiving groove of an information recording medium is detected. At the same time, a light beam passing through the thruhole 46 and reflected by the information recording medium is received by a photo detector for inclination detection whereby the inclination angle of the objective lens against the information recording medium is detected.
|
