OPTICAL RECORDING MEDIUM HAVING WRITE ONCE METAL REFLECTION FILM

摘要

A pirated optical recording medium may be determined which is produced by physically transferring a shape of pits and lands formed on a substrate of an optical recording medium. The optical recording medium is provided with excellent weatherability and long-term storage reliability. A reflective film formed of an Ag alloy film of Ag 100-x-y X x Cu y , where X is at least one element among Ti, W, Ta, V, Mo, Nb and Zr, is formed on a substrate on which main data is recorded with a combination of pits and lands. A mark may be formed so that a reproduction signal level in the recorded mark of auxiliary data write once recorded on the reflective film is increased, and a reproduction signal level is decreased in an optical recording medium prepared by physically transferring the surface shape of the pits and lands of the substrate. A pirated optical recording medium may be determined in this manner.