| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical information recording medium having a protrusion part protecting a transparent protective layer and reducing a load to a motor at the time of rotation and capable of obtaining larger disk holding force. <P>SOLUTION: In the optical data recording medium having a signal substrate, a signal recording layer and the transparent protective layer provided on the signal recording layer and having 10 to 200 μm thickness and further having a center hole, recording or reproduction of data is performed by irradiating the signal recording layer with light through the transparent protective layer, a holding region is formed in a region between a signal region corresponding to a region where the signal recording layer is formed and the center hole, the protrusion part protruding from the surface of the transparent protective layer is provided on a light incident surface side in a region interposed between the center hole and the holding region and the protrusion part is formed by using a material different from the material of the transparent protective layer. <P>COPYRIGHT: (C)2007,JPO&INPIT |
