Patent ID: 6424609
Filing Date: 2002-07-23
Classification: G11B

Abstract:
An output control device for an optical pick-up used in an optical disc drive for reproducing and recording an optical disc, the optical pick-up being adapted to project light having a quantity of light of either high level for forming pits or low level for forming lands or reproducing the optical disk to the optical disc, the output control device comprising:light receiving means having a plurality of light receiving regions for receiving reflected light from the optical disc and then outputting electrical currents responsive to the quantity of light received at the respective light receiving regions; current-voltage converting means having a first current-voltage converting section for converting the currents supplied from the light receiving means into voltages through a predetermined amplification factor and a second current-voltage converting section for converting at least a part of the currents supplied from the light receiving means into voltages through a predetermined amplification factor which is lower than that of the first current-voltage converting section; and current supply changeover means having functions that supplies the current from the light receiving means to the first current-voltage converting section when the quantity of the reflected light from the optical disc is in the low level wherein the light has a quantity of light of the low level being projected, and that supplies at least a part of the currents from the light receiving means to the second current-voltage converting section without supplying the currents to the first current-voltage converting section when the quantity of the reflected light from the optical disc is in the high level wherein the light has a quantity of light of the high level being projected.