Information recording and reproducing apparatus having semiconductor laser drive circuitry in its pickup

Abstract

A laser waveform generation function is provided in a laser driving waveform generator near a laser A recording clock generator is included in the laser driving waveform generator to generate a clock with a frequency higher than that of a synchronizing clock This allows a recording laser current (waveform) to be generated without transmission of a high frequency signal from the modulator Further, because the synchronizing clock is stopped upon a reproduction operation including reproduction operation in an ID unit, undesired effects on a reproduction operation such as ID reproduction can be reduced. Because the response speed of the recording clock generator can be changed, a high precision clock can be generated. Thus, a high-precision recording laser current (waveform) can be generated.