COVER LAYER STRUCTURE FOR OPTICAL DATA STORAGE MEDIA

摘要

The invention is directed to a cover layer structure for an optical data storage disk. The cover layer structure includes an optically transmissive layer, a first material distributed over a top surface of the optically transmissive layer, and a second material distributed over a bottom surface of the optically transmissive layer. The first and second materials may comprise curable materials optically matched to the optically transmissive layer. The optically transmissive layer defines substantial thickness variations larger than approximately ± 2 µm. The first and second materials are distributed over the optically transmissive layer such that a thickness variation tolerance of the cover layer structure is less than approximately ± 2 µm. In some cases, the first material may comprise a hardcoat material and a single structure comprising both the hardcoat material and the optically transmissive layer may bond to a substrate of the optical data storage disk.