| 摘要 |
PURPOSE:To enable the erasure of information every bit by arranging layers of light-absorbing materials which selectively indicate the significant absorption of different various wavelengths from those of optical pulses used for the recording and retrieval of information, adjoining an optical recording layer. CONSTITUTION:If the pulses of a laser beam (L) passing through an objective lens 5 are transmitted into an optical recording medium from a substrate side, a light-absorbing substance layer 2 is formed on a substrate 1. This light- absorbing substance can indicate the significant absorption of a wavelength lambda2 as shown by an absorption spectrum curve II. An optical recording layer 3 is formed on the light-absorbing substance layer 2. The material of this opeical recording layer 3 indicates properly significant light absorption and is transformed from a high crystallinity state to a low crystallinity state through heating and quenching. Conversely said material is transformed from a low crystallinity state to a high crystallinity state through heating and slow cooling. In addition, a protection coat 4 of metal oxides such as SiO2, Al2 and O3 is applied to the optical recording layer 3. |
