| 摘要 |
Provided is a light-spot-position control apparatus including: a first-light-source; a second-light-source; a beam-splitter splitting a beam of the second-light-source into m beams; an optical-system allowing a first-beam of the first-light-source and the m beams to irradiate a disk-shaped recording-medium, where grooves and lands are alternately formed with an equal radial width to form the grooves in spiral/concentric shape through common-objective-lens, the optical-system allowing the three beams to irradiate the recording-medium so that an interval of m beam-spots is 1/m of track pitch; a tracking-control-mechanism tracking-controlling the beam by changing a relationship between the optical-axis and the recording-medium; a light-receiving unit individually receiving the m beams; an error-signal generator generating error-signals representing radial-position-errors of the spot-positions of the m beams with respect to the tracks based on received signals; an error-signal selector selecting at least one error-signal; and a servo-controller controlling the tracking-control-mechanism to tracking-servo the beam based on the error-signal.
|
