This standard specifies the mechanical characteristics that enable compatibility of 120 mm [4.7 GB/side] and 80 mm (1.46 GB/side) DVD-rewritable discs (hereinafter referred to as discs). It specifies physical and optical properties, as well as the quality of recorded signals, data formats, and recording methods that enable information exchange. Data can be written, read and overwritten multiple times using phase change techniques. Two types of capacity are specified depending on the diameter: 120mm and 80mm.
JIS X 6246:2005 history
2005JIS X 6246:2005 120 mm (4.7 Gbyte per side) and 80 mm (1.46 Gbyte per side) DVD rewritable disk (DVD-RAM)