OPTICAL STORAGE MEDIUM

摘要

An optical storage medium comprising a storage layer ( 4 ) and a first layer ( 5 ) covering the storage layer ( 4 ). The first layer ( 5 ) provides optical properties sufficient for data retrieval from the storage layer using a laser ( 8 ) with a first wavelength W₁. A second layer covers the first layer ( 5 ) and provides optical properties sufficient for data retrieval from the storage layer using a laser with a second wavelength W 2.