| 摘要 |
<P>PROBLEM TO BE SOLVED: To irradiate with light having uniform intensity with respect to substantially an entire recordable region of a second information recording layer of an optical recording medium having a first and the second information recording layers from a light incident side. <P>SOLUTION: The optical recording medium is a disc-shaped medium including the first and second recording layers 10 and 8, which are laminated. Information can be recorded onto or reproduced from the recording layers 10 and 8 independently using incident light entering from one side of the medium. A recordable region of the first recording layer 10 on the light incident side has an extension region 62 at an innermost peripheral end portion or an outermost peripheral end portion in a radial direction. The length in the disc radial direction of the extension region 62 is set so that when light is focused to an innermost peripheral end portion or an outermost peripheral end portion of the second recording layer 8, the light transmits through the recordable region including the extension region of the first information recording layer. A region for test writing is allocated in the extension region 62 and the region is entirely included in the extension region 62. The light recording/reproduction apparatus performs test writing in the region for test writing. <P>COPYRIGHT: (C)2008,JPO&INPIT |
