【国外标准】 Information technology - Case for 120 mm DVD-RAM disks

Specifies the characteristics of a case for use with 120 mm DVD-RAM disks as specified in Standard ECMA-ppp. The present International Standard specifies three related, but different implementations of such cased, viz. Type 1 Provides a case for a one-sided (Type 1S) or a two-sided (Type 2S) DVD-RAM disk such that the disk can not be removed from the case. This case is reversible. Type 2 Provides a case for a one-sided DVD-RAM disk (Type 1S) such that the disk may be removed from the case. This case is not reversible. Type 3 Provides a case into which a one-sided DVD-RAM disk (Type 1S) may be inserted, then used as a cartridge. This case in not reversible.