need time to cool down after at it has decomposed due to  its  thermal  iner-

re-heat and post-he-at³, and thermal accu-mulation
   Considering that now we are able to get a good media based on the right dye deposited on a disc with the right groove geometry and the right thickness(es), does it guar-antee good recording performance? This is an excellent question. As we had already noticed it, mark distortion is a major concern during recording. The reason is simple. With recordable DVD we have on one hand smaller marks, and on the other hand smaller intervals (land) between marks. The combination of

tia. In that case it may continue to de-compose as the laser has been already switched off. But it will tend also to propagate its heat in its neighbour-hood and depending of the size of the space that separates it from previous mark or following mark, it might affect it too. Let’s firstly have a look at the diagram temperature on the right part of figure 12 for a clear und-erstanding of what we call thermal interference. As we all know DVD is characterized by a set of pits and lands with the shortest one which is 3T and the longest one which is 14T. One period length is equal to 38.2 ns at  1x  with  a  CLV  of  3.49  m/s.   It

14T mark (and land) 1.866 µm long. Due to these thermal interfe-rences these specific lengths will be subject to variations. These variat-ions will occur in many different ways as the different marks and spaces will form and align along the track in many different combin-ations. Depending how longer or shorter than their specific length these marks/spaces are, this will create more or less jitter which is the statistical representation of these deviations with regard to these specific lengths. To decom-pose, dye has to reach a certain temperature. Then it  cools  down. 

these small size marks and spacing will be subject to thermal interfe-rence between marks and of course this effect becomes more acute as recording speed increases. This is where write strategies (WS) must be correctly tailored to minimise the consequences in terms of deviation and jitter. Dye materials have dif-ferent thermal characteristics and react differently during recording. But they all have more or less the same problem. The dye may need a little bit of time to react to the laser. More important is that  the  dye  will

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