別人寫的,看看吧

Quoted from http://www.mscience.com/faq53.html

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Longevity is no longer limited by the stability of the dye, but instead depends on two other issues. The first issue is the original quality of the recorded disc.Each dye and recording speed requires a different optimum recording power and write strategy. CD-R writers vary in their capability to provide optimum recording conditions. Inconsistent recorded quality is the result, even though initial quality must be high if the disc is to degrade gracefully over its lifetime.
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