| 摘要 |
<p>A dual-stack optical data storage medium (10) for write-once recording using a focused radiation beam (9) having a wavelength lambda of approximately 655 nm is described. The radiation beam enters through an entrance face (8) of the medium (10) during recording. The medium comprises at least one substrate (1, 7) with present on a side thereof: - a first recording stack (6), named L0, comprising a write-once type L0 recording layer, said first recording stack L0 having an optical reflection value RL0 and an optical transmission value TL0, a second recording stack (3), named L1, comprising a write-once type L1 recording layer, said second recording stack L1 having an effective optical reflection value RLleff. The first recording stack (6) is present at a position closer to the entrance face (8) than the second recording stack. (3). A transparent spacer layer (4) is sandwiched between the recording stacks (3, 6). The reflection values RL0 and RL1 eff are within the following ranges: 0.12 <= RL0 <= 0.18 and 0.12<= RL1eff <= 0.18 by which an improved sensitivity of the dual stack medium is achieved.</p> |
