Optical disk, recording method, recording medium, and optical disk unit, for recording information on multilayer optical disk

Abstract

A method of recording information using a laser on a multilayer optical disk having a plurality of recording layers is provided. The plurality of recording layers include a first recording layer and a second recording layer adjacent the first recording layer. The first recording layer is provided with a first test writing area to be used for calibration of write power, and the second recording layer is provided with a second test writing area to be used for calibration of write power. The disk is arranged so that a first region of the first test writing area is superposed with a second region of the second test writing area when considered in the direction in which the laser is arranged to irradiate. The method comprises, if the second region of the second test writing area is unrecorded, recording data in the second region of the second test writing area, thereby converting the second region of the second test writing area into a recorded state; and once the second region of the second test writing area has been converted into a recorded state, performing test writing in the first region of the first test writing area.