| 摘要 |
PURPOSE:To improve the dependent properties of the optimum recording power onto the ambient temperatures and the recording frequencies, by driving a light source with a larger and/or smaller current than the normal recording and/or non-recording current for an optional fixed period from the rise and/or the fall of an input signal. CONSTITUTION:A laser is turned on at a writing level at a time point I. In this case, the rise of a medium temperature has the larger gradient than usual since the power is larger than usual at the point I. Then the laser is turned on by the normal recording power at a time point II since the medium temperature rises and exceeds a temperature T0 that is needed for recording. A writing task is through at a time point III and the level of power is lowered than the normal level in order to quicken the drop the medium temperature. In this section specific time is set so that the servo control of a recording device is not affected at all even though the recording power is substantially equal to zero. Therefore the maximum temperature has the large rise and fall gradients at each point of the recording layer of a medium which moves relatively to an illuminated laser spot. Thus it is possible to improve the dependent properties of the optimum power onto the ambient temperatures and the recording frequencies.
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