Patent ID: 8107342
Filing Date: 2012-01-31
Classification: G11B

Abstract:
1. A laser driving device comprising: a first pulse generating section configured to generate a reference pulse indicating timing of changing between a space and a mark by detecting an edge of a first transmission signal indicating, by said edge, information defining timing of obtaining said reference pulse; a second pulse generating section configured to generate a changing pulse indicating changing timing of divided power levels of respective light emission waveforms of said space and said mark by detecting an edge of a second transmission signal indicating, by said edge, information defining timing of obtaining said changing pulse; a light emission waveform generating section configured to output reference level information as level information on a level at a position of said reference pulse, said level information being included in power level information on each power level of said light emission waveforms, for each reference pulse, and output other level information following said reference level information in order for each changing pulse; a light emission level pattern storing section configured to store a recording waveform control signal pattern indicating the level information for said light emission waveforms; a second storing section including a plurality of auxiliary storing sections configured to store a plurality of respective different pieces of setting information, a main storing section configured to selectively store one of the pieces of setting information stored in the plurality of auxiliary storing sections, and a stored information controlling section configured to select one of the pieces of setting information stored in the plurality of auxiliary storing sections and make said main storing section store the setting information; a sample-hold section configured to sample and hold an electric signal based on laser light emitted from a laser element; and a sampling pulse generating section configured to generate a sampling pulse for sampling and holding said electric signal with an edge of light emission waveforms based on said reference pulse and said changing pulse as a reference, and supply the sampling pulse to said sample-hold section, wherein said light emission waveform generating section reads the reference level information as level information on the level at the position of said reference pulse, said level information being included in the power level information for each of said light emission waveforms stored in said light emission level pattern storing section, for each reference pulse, and reads the other level information following said reference level information in order for each changing pulse, said second storing section is used also as a sampling pulse pattern storing section storing setting information defining a pulse pattern of said sampling pulse, said plurality of auxiliary storing sections store a plurality of respective different pieces of setting information defining a pulse pattern of said sampling pulse, and said sampling pulse generating section generates said sampling pulse on a basis of said setting information stored in said main storing section.