High density write-once optical disk for HDTV

We have developed a high density write-once optical disk by utilizing the reflection plane shift recording method and a 670nm short-wavelength laser diode. A high CNR of 60dB at 12.5MHz has been obtained, which is enough to record and play back MUSE encoded HDTV signals on a disk. A 42 dB SNR of the HDTV signal recorded has been obtained. Recording and playing back a digital ATV signal was also carried out on the write-once disk. It was demonstrated that a 32QAM-FM modulated ATV signal could be recorded on the disk.