Disc device

Abstract

An optical disk apparatus can optimize recording power in a recording-capable optical disk. The recording power is optimized by an OPC. A controlling part diversifies the recording power to record test data and computes the modulation factor m of a reproducing RF signal. An inflection point where the inclination of variation of the modulation factor m to the recording power varies is extracted, and the optimum recording power is a value obtained by the multiplication by a prescribed parameter to the recording power corresponding to the inflection point as the target recording power. The target recording power is a recording power whose modulation factor m becomes zero from the inclination in variation to the recording power of the modulation factor m, and the optimum recording power is obtained by the multiplication by the prescribed parameter to the target recording power.

Description

technical field [0001] The present invention relates to an optical disc device, and more particularly to a technique for optimizing recording power when recording data on a recordable optical disc. Background technique [0002] In the public knowledge, the specified field of the optical disc is specifically in the power calibration area (Power Calibration Area, PCA) formed in the inner peripheral part of the optical disc, under the recording power divided into multiple segments, test and record the random EFM data of the change, and A well-known OPC technique for optimizing recording power. Specifically, from the reproduced RF signal of the test recording data, it can be calculated by the power function (γ). Recording power is used as a reference to determine the optimum recording power. Furthermore, the γ value is defined as follows based on the modulation degree m of the reproduced RF signal and the recording power Pw. [0003] [mathematical formula 1] [0004] γ=(dm / d...

AI Technical Summary

Problems solved by technology

And when it is difficult to determine the original optimal recording power, it will be difficult to maintain the recording quality (waveform fluctuation, error rate, etc.)

Specifically, when using recording power significantly lower than the original optimum recording power for recording, it will cause adverse effects on fluctuation or error rate; conversely, when using significantly higher than the original optimum recording power In the case of recording with recording power, it will have a bad influence on the durability of repeated recording.

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