Thermal Relaxation Time – what is wrong with it?

  The theory which has underpinned many skin-laser treatments since 1981 is called ‘Selective Photothermolysis’. It is based on matching the laser wavelength to the absorbing chromophore. It also matches the pulse duration of the laser to the thermal relaxation times of those targets. However, there is a problem with this approach. The thermal relaxation… Continue reading Thermal Relaxation Time – what is wrong with it?

Tissue denaturation – the process

  And here it is, in black and white…. This wonderful little equation describes how hair, blood, collagen or any other protein denatures as a function of time and temperature. It is important to understand how this works if you want to treat these proteins properly. Most people have never even heard of it, yet… Continue reading Tissue denaturation – the process

Advanced Laser-Tissue Interactions Course

New Advanced Laser-Tissue Interactions Course Finally, a course designed to outline a deeper understanding of the processes involved when applying laser/IPL energy to the skin.  Topics include: Light transport in tissues; Thermodynamic effects; Selective Photothermolysis; Tissue denaturation; Arrhenius damage integral…..   And more! Using recently developed computer models this course describes the more important processes… Continue reading Advanced Laser-Tissue Interactions Course

LSO (Laser Safety Officer) Training

I’ll open with the fact that I am a Certified Laser Protection Adviser (LPA) and a committee member of the Association of Laser Safety Professionals. I am also a member of ASLMS, the BMLA and the ELA. As such, I can go into a laser/IPL centre and carry out a safety assessment to ensure that… Continue reading LSO (Laser Safety Officer) Training

“No Pain, No Gain” – hair removal using light energy!

OK! PDF version This is really quite simple! Human thermal/pain receptors (nociceptors) are triggered at around 45 C. Below that temperature you feel heat – above it, and you feel pain. NASA has proved this beyond doubt! So, to achieve permanent, or even ‘semi-permanent’ hair removal you need to apply sufficient heat energy, for a… Continue reading “No Pain, No Gain” – hair removal using light energy!