Optical memory apparatus

An optical memory apparatus comprising:

• a recording medium on which predetermined information is optically recorded along tracks from which it is played back, wherein the tracks fluctuate due to at least the eccentricity thereof,
• projecting means for projecting a laser beam onto the recording medium as a light spot,
• light receiving means for receiving reflected light from the recording medium and providing an output indicative thereof,
• means for generating a tracking signal for causing the laser beam to move along the track in response to the output from the light receiving means,
• a first actuator for moving the projection means radially with respect to the recording medium,
• a second actuator having a rate of response higher than the first actuator for moving the light spot radially on the recording medium to follow the desired track in response to the tracking signal,
• detecting means for detecting the movement of the second actuator at least during movement of the second actuator to follow the desired track and for providing an output indicative thereof, and
• the first actuator being actuated in response to the output of the detecting means during the movement of the second actuator to follow the desired track so that the extent of displacement of the light spot actuated by the second actuator is smaller than the extent of fluctuation of the desired track and the light spot follows the desired track in accordance with the movement of the first actuator and the second actuator.