To provide an output waveform control circuit capable of increasing the number of respectively consecutive '1' or '0' bits in an ALL '1' signal and an ALL '0' signal so as to confirm whether or not a waveform of '1' and '0' of a CMI (Coded Mark Inversion) signal satisfies a pulse mask with high reliability. ALL“1”信号及びALL“0”信号の、それぞれ“1”又は“0”の連続するビット数を大きくでき、CMI信号の“1”及び“0”の波形がパルスマスクを満足するか否かの確認を高い信頼度で得ることが容易にできる。 - 特許庁