THE CHARACTERISTICS OF A DUAL-LAYER OPTICAL DISK WITH READ-ONLY AND ERASABLE FUNCTIONS

A dual-layer optical disk comprised of a read-only layer and a phase-c hange layer was designed to perform the read-only and erasable dual-fu nctionality in an optical disk. With the properly designed dual-layer disk structure, 23 mW of write power was adequate to write data marks on the erasable phase-change layer; simultaneously, equal magnitude of sufficient radiofrequency readout signals could be obtained on both i ts data layers. The analyzes of its recording characteristics demonstr ated the feasibility of the dual-functional optical disk.