| 摘要 |
The writing and reading of optical data is made using an optical data writing medium (5) and a single light spot, and the verification is made simultaneously with the writing of data. A phase transition optical disk is used as the optical data writing medium. The verification is made by checking magnitude of Iw x (Pr/PW) and that of Ir, wherein Iw is a return light dose from the optical data writing medium during writing, Ir is a return light dose from the optical data writing medium in a crystal state of the writing film, Pw is laser power during writing, and Pr is laser power during reading. The device for writing and reading optical data includes a divider (7) for dividing a return light dose Iw from the optical data writing medium during writing by Pw,/Pr, and a comparator (8) for judging magnitude of Iw x (Pr/Pw) and that of a return light dose from the optical data writing medium. The verification by a single beam spot while data is being written enables the reduction of writing time. <IMAGE> |
