| 摘要 |
PURPOSE:To reduce the number of manufacturing processes and to perform the recording, reproduction and erasure of data by a reduced quantity of laser power at the time of writing and erasure, by utilizing the reflected beam from a recording film itself in reading and providing no reflecting layer close to the recording film. CONSTITUTION:A recording layer 2 being a single layer film is formed on a substrate as a recording film. This recording layer 2 is a mixed film formed so as to have the max. absorption values of three beams different in a wavelength. In this recording medium, when the recording layer 2 changes by the irradiation of recording laser beams, beam absorption is newly generated in a separate wavelength. Since wavelength of this beam absorption is different corresponding to the wavelength of the recording laser beam, by detecting the presence of said beam absorption, reading can be performed. Three recording layers 4, 6, 8 and intermediate layers 5, 7 are successively formed on a substrate 3. Herein, the recording layers 4, 6, 8 respectively have different absorption max. values of beam and each of them is composed of each dye generating the absorption max. value of beam at each wavelength. By this arrangement order of the recording layers, the generation of beam attenuation or noise due to beam absorption of the layer 4 at the time of the reading of the layer 6 or 8 and that of the layer 4 and the layer 6 at the time of the reading of the layer 8 can be avoided. |
