Page 55 - Chapter 3 - Laser/IPL Hair Removal

Chapter 3 – Fundamentals of Laser/IPL Hair Removal 2nd Edition
Figure 19 - Raising the temperature of the cells/tissues increases the denaturation rate significantly – thereby requiring less time to kill all the cells
This means that the pulsewidth does not directly relate to the denaturation process! In fact, figures 17, 18 and 19 all show that most of the denaturation process will occur in the cooling
phase – not during the pulsewidth (heating) phase. This is where most of the denaturation zone lies. The TRT lies within the denaturation zone, but only the first part of it. The denaturation process may continue long after the end of the TRT – but again, it is not directly linked to the cooking process or time.
This analysis shows that the pulsewidth, TRT and denaturation times are not directly linked. There is a relation of sorts, but it is quite tricky to figure out!
In summary, the three important times are:
Pulsewidth – the light energy ‘delivery’ time Relaxation time – the ‘cooling’ time Denaturation time – the ‘cooking’ time of the cells
________________________________________________________________________ 55 Chapter 3, Ed. 2.0 Laser/IPL Hair Removal
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