COMBINED FLUORESCENT-REFLECTIVE MEDIA AND MEDIA READING DEVICE

摘要

The invention relates to optical media of ROM, WORM or RW type that combine the ability to write and read data from one layer using fluorescent and reflective methods. Data is recorded as pits of different depth situated either in two alternating spiral tracks or in the same track. Data is read either sequentially, e.g. first fluorescent signal, than reflective signal, or simultaneously, by using two optical heads, one that is fluorescent and the other that is optical.