| 摘要 |
<P>PROBLEM TO BE SOLVED: To perform reliable recording/playback without depending on the number of a recording layers. <P>SOLUTION: A beam is reflected by a high reflectance metal layer R formed on a further deeper side of an L0 recording layer which is the deepest in the incident direction of the beam to initially perform spherical aberration correction corresponding to the optically deepest S0 recording surface. Thereby, recording/playback to respective recording surfaces (S0 to S5) after that can be reliably performed. At this time, an optical recording medium satisfying a relational formula T0≤(MT-CL)/2 is used when a distance from the L0 recording layer located on the deepest side to the incident beam to the high reflectance layer R, a distance from the surface of the optical recording medium to the S0 recording surface located on the deepest side and a distance from the surface of the optical recording medium to the nearest L0 recording layer are defined as T0, MT and CL, respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT |
