OPTICAL DISK AND OPTICAL DISK DEVICE

摘要

When recording on/reproducing from an optical disk with many recording layers, the tilt margin of each recording layer is reduced with the distance of the recording layer from the laser beam incident surface. For example, when the respective recording layers have a fixed recording density, a sufficient recording/reproducing performance becomes difficult to ensure for a recording layer positioned away from the laser beam incident surface. The present invention provides an optical disk and an optical disk device capable of ensuring a sufficient recording/reproducing performance by appropriately changing the recording density of each recording layer even when multiple recording layers are laminated for an optical disk having a guide layer and recording layers, for example.