Patent ID: 6731586
Filing Date: 2004-05-04
Classification: G11B,H01S

Abstract:
An auto laser diode power controlling apparatus for controlling the output of a laser diode (LD) the apparatus comprising:a photo detector (PD) which monitors a current power level of an optical signal output by the LD to output a current power level signal; a sampler and holder which samples and holds the current power level signal to output a sampled and held current power level signal; a sample and hold control signal generator which generates a sample and hold control signal to control the sampling operation of the sampler and holder on the basis of a non return to zero inverted (NRZI) signal, wherein: the sample and hold control signal generator comprises: a delay which receives a power level control signal corresponding to a recording pulse and generates a plurality of delayed power level control signals having different delay amounts, and a multiplexer and gate which combines the plurality of delayed power level control signals to generate the sample and hold control signal; and an operator which compares the sampled and held current power level signal with a reference power level and controls the output of the LD according to a difference between the sampled and held current power level signal and the reference power level.