Patent ID: 7697385
Filing Date: 2010-04-13
Classification: G11B

Abstract:
1. A method of controlling a recording laser power for a disc-shaped recording medium on which an address signal is previously recorded for every prescribed recording unit related to a track in the disc-shaped recording medium, wherein an information signal is recorded on the disc-shaped recording medium in cases where a laser beam containing the information signal is applied to the disc-shaped recording medium while the disc-shaped recording medium is driven and is scanned by the laser beam on a constant-linear-velocity basis, the method comprising the steps of: sequentially generating test signals; applying a laser beam inclusive of the generated test signals to a preset test recording area in the disc-shaped recording medium while driving the disc-shaped recording medium at a predetermined constant linear velocity relative to the applied laser beam to record the generated test signals on the preset test recording area in the disc-shaped recording medium; changing stepwise a recording power of the applied laser beam from a lowest level to a highest level through different intermediate levels, wherein the lowest level, the highest level, and the intermediate levels the recording power of the applied laser beam takes are assigned to the generated test signals respectively; reproducing the recorded test signals from the preset test recording area in the disc-shaped recording medium; and deciding an optimum value of a laser-beam recording power on the basis of the reproduced test signals and at least one of the lowest level, the highest level, and the intermediate levels; wherein the changing step comprises: changing stepwise the recording power of the applied laser beam from the lowest level to a reference level selected from the intermediate levels through ones of the intermediate levels which are lower than the reference level; changing stepwise the recording power of the applied laser beam from the reference level to the highest level through ones of the intermediate levels which are higher than the reference level; and during the stepwise change of the recording power from the reference level to the highest level, setting the recording power of the applied laser beam to a prescribed level for each of spaced time intervals corresponding to portions of the disc-shaped recording medium on which address signals are previously recorded respectively; wherein the prescribed level is equal or close to the reference level.