| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable the measurement of a reproduction jitter of a reproduction signal in case of the occurrence of intersymbol interference in the reproduction signal and to optimally set a recording laser pulse with the reproduction jitter as an index. <P>SOLUTION: The amplification value data of the reproduction signal at a prescribed sampling timing is acquired in an A/D conversion section 8. Viterbi decoding is performed relating to the amplification value data of the reproduction signal in a maximum likelihood decoding section 10. The binary data of the reproduction signal is decoded to form the amplification value data of the equalization signals having ideal PR (1, 2, 2, 2, and 1) characteristics in a partial response equalization section 13. A prescribed pattern is detected in a pattern detector 14. A reproduction jitter calculation section 1501 calculates the reproduction jitter from the expected value error of the amplification value data of the reproduction signal of the edge with respect to the amplification value data of the equalization signals of the edge of the mark included in the prescribed pattern. A laser pulse controller 1502 sets the waveform of the recording laser pulse based on the reproduction jitter. <P>COPYRIGHT: (C)2008,JPO&INPIT |
