OPTICAL INFORMATION RECORDING AND REPRODUCING DEVICE

摘要

PURPOSE:To reduce both the required accuracy and the cost of optical parts by using a waveform equalizer having the frequency characteristics accordant with the residual aberration of an optical system to perform the waveform equalization of the output signal of a photodetector. CONSTITUTION:The 2nd waveform equalizer 10 is set between a photodetector 8 and the 1st waveform equalizer 9. The equalizer 10 has the frequency characteristics corresponding to the residual aberration of an optical system and corrects the output signal of the detector 8 so that it is equivalent to the signal read out through a non-aberration optical system. Then the equalizer 9 amplifies the high band of the output signal of the equalizer 10 to increase the opening amount of a reproduction signal. Thus the jitter due to the aberration is corrected electrically. This can reduce the required accuracy of optical parts.