| 摘要 |
PURPOSE:To minimize fluctuation in reflectivity with respect to variance in the thickness of a dye film and to obtain an optical information recording medium at a good yield by providing the light absorptive and reflective dye film in a way as to have the film thickness at which the reflectively is maximized on a substrate. CONSTITUTION:Small recesses 6 are preliminarily provided on a transparent substrate 2 consisting of plastic, glass, etc. during irradiation of a recording or reproducing laser beam in order to form preliminarily pregrooves for tracking control, addresses or other necessary information in the stage of forming the dye film 3 on the substrate by coating a soln. of a cyanine dye, etc. thereon. If the film 3 is formed on such film 2, the recesses 6 have the tendency to be formed more thickly by 5-30% than the projecting parts and therefore the film 3 is formed at such a thickness at which the reflectivity is maximized to minimize the difference in the reflectivity between the recesses 6 and the projecting part. The stable tracking detection signal and preformat signal are thus obtd. |
