120 mm DVD- Read-Only Disk

ECMA Technical Committee TC31 was established in 1984 for the standardization of Optical Disks and Optical Disk Cartridges (ODC). Since its establishment, the Committee has made major contributions to ISO/IEC SC23 toward the development of International Standards for 90 mm, 120 mm, 130 mm, 300 mm, and 356 mm media. Numerous standards have been developed by TC31 and published by ECMA, almost all of which have also been adopted by ISO/IEC under the fast-track procedure as International Standards. In February 1997 a group of ten Companies, known as the DVD Consortium, proposed to TC31 to develop an ECMA Standard for the first member of a family of 120 mm optical disks. TC31 adopted this project and started work on a first ECMA Standard for DVD- Read-Only disks. This ECMA Standard specifies the physical characteristics of such a disks which can be used for video, audio or data applications. A standard for volume and file structure common to these three types of application has been developed in ECMA Technical Committee TC15. Further work has been undertaken for a rewritable disk known as DVD-RAM, for a case for such disks, and for a writable disk DVD-R. This work is supported by nine members of the DVD Forum. This Standard ECMA-267 specifies four Types of DVD- Read-Only disks with a nominal capacity from 4,7 Gbytes to 17,0 Gbytes. Standard ECMA-268 specifies a 80 mm DVD- Read-Only disk which differs from that of this Standard ECMA-267 only where the relevant parameters depend on the dimension of the diameter. Four Types of such DVD disks wit