Patent ID: 7065114
Filing Date: 2006-06-20
Classification: G11B

Abstract:
1. An apparatus for controlling power to be supplied to a laser diode for writing on an optical disc, wherein one pulse of the power is composed of an overdrive power level and a base power level that follows the overdrive power level, the overdrive power level being higher in level and narrower in width than the base power level, the base power level corresponding to a base power current, the overdrive power level corresponding to a sum of the base power current and an overdrive power current, said apparatus comprising: a base power control signal monitor that monitors the base power control signal; an LD (Laser Diode) output level monitor that monitors a power level output by said laser diode; a base power controller that controls the base power current so that a power level monitored by said LD output level monitor matches a preset target value; an overdrive power generator that generates the overdrive power current; and a main controller that, at a correction time of the power level, allows said overdrive power generator to set the overdrive power current to zero, that allows said base power controller to increase the base power current with a target value of the base power level set to the overdrive power level that is desired, and that, when the base power level has reached the target value, allows said overdrive power generator to increase the overdrive power current until the base power control signal monitored by said base power control signal monitor reaches a value corresponding to a desired base power level.