Dual-layer write-once media with Te-O-Pd recording films for lx-4x speed recording based on Blu-ray Disc format

摘要

We have developed dual-layer write-once media with Te-O-Pd based recording films on Blu-ray Disc (BD) format. Recording capacity was 50GB with dual layers on a disk of 120mm in diameter. We adopted high-transmittance structure to Front layer, and high-sensitive structure and O-rich compound of Te-O-Pd to Rear layer, which enables to obtain good jitter values enough to satisfy BD format. Characteristics at 4x speed recording were also examined, and it was revealed that carrier to noise ratio at high recording linear velocity of 19.7m/s, which corresponds to BD 4x (144Mbps), was almost as same as those of 1x and 2x. These technologies will enable high-speed and high-density write-once media on BD format.