| http://www.w3.org/ns/prov#value | - These metals may be used alone or at least two types of them may be used in combination at an optional ratio.The film thickness of the reflective layer is usually at least 3 nm, and usually at most 400 nm, preferably from 50 to 300 nm.The cover layer is made of a material transparent and low birefringence for laser beam used for recording and reproduction.
|
