Patent ID: 7894315
Filing Date: 2011-02-22
Classification: G11B

Abstract:
1. A method of recording information using a laser on a multilayer optical disk having a plurality of recording layers, the plurality of recording layers including a first recording layer and a second recording layer, the second recording layer being a recording layer adjacent the first recording layer, the first recording layer having a first test writing area to be used for calibration of write power and the second recording layer having a second test writing area to be used for calibration of write power, wherein the first test writing area is completely superposed with the second test writing area when considered in the direction in which the laser is arranged to irradiate, the method comprising: if a 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; once the second region of the second test writing area has been converted into a recorded state, performing test writing in a first region of the first test writing area; and wherein before performing the test writing in the first region of the first test writing area, if the first region of the first test writing area is unrecorded, the method comprises: recording data in the first region of the first test writing area, thereby converting the first region of the first test writing area into a recorded state, and then clearing the first region of the first test writing area; and wherein the clearing of the first region of the first test writing area comprises performing an erasure operation to make the first region unrecorded; and wherein the method further includes the step of recording dummy data in the first recording layer, and wherein the step of recording dummy data in the first recording layer occurs subsequent to the step of performing the test writing in the first region of the first test writing area.