Patent ID: 8165006
Filing Date: 2012-04-24
Classification: G11B

Abstract:
1. An optical disc device for at least reproducing data recorded in a multilayered optical disc configured of a plurality of multilayered recording layers, the optical disc device comprising: a light source for outputting a light beam with light intensity according to a driving current; a light intensity controller for supplying the driving current, on which a high frequency signal is superimposed, to the light source and controlling the light intensity of the light beam output from the light source; an objective lens for collecting the light beam on any one of the recording layers of the multilayered optical disc; a photodetector for receiving reflected light of the light beam from the multilayered optical disc; an error signal generator for generating an error signal based on the reflected light received by the photodetector; an actuator for moving the objective lens relative to the multilayered optical disc; and a controller for controlling the actuator based on the error signal, locating a focal point of the light beam on a recording layer of the multilayered optical disc, and controlling reproduction of data recorded in the recording layer; and wherein the light intensity controller includes: an automatic power control unit for controlling the driving current supplied to the light source based on the error signal; and a superimposed amount adjustor for adjusting a superimposed amount of the high frequency signal so as to suit to a specific recording layer with the lowest reproduction tolerance in the multilayered optical disc as triggered by detection of servo deviation based on the error signal while the controller controls data reproduction.