What is it like to ‘sit’ on a photon and be fired into the skin?

Let’s take a ride on a photon. Imagine we can sit on a photon. What would a trip into the skin be like? Well, it might be something like this…. As we leave the laser we will be travelling at nearly the speed of light – that is 30 million kilometres per second! However, as… Continue reading What is it like to ‘sit’ on a photon and be fired into the skin?

Laser-IPL Penetration Depth – a more useful definition

The ‘standard’ definition of penetration depth in skin only considers the incident wavelength and optical properties of the skin. While this may be useful from a physics perspective, it is not particularly useful when considering clinical treatments. A more useful definition must include wavelength, anisotropy, spot diameter and incident fluence. All of these have an… Continue reading Laser-IPL Penetration Depth – a more useful definition

Tattoo removed in just 4 sessions using a QS Nd:YAG at 1064nm

The following is an experiment I carried out to test a theory. A number of experiences had made me think that the time between laser sessions is more important than first thought. My clinical group first developed scar-free laser tattoo removal back in the 1980s in Canniesburn Hospital, Glasgow, Scotland. Back then, we were using… Continue reading Tattoo removed in just 4 sessions using a QS Nd:YAG at 1064nm

Laser spot size – how it changes with distance from the target…

Most laser systems have a lens to focus the laser energy down to a sale spot diameter (see figure 1 below). However, in many systems, the focal point (where the spot diameter is the smallest) is outside the handpiece assembly. This has a potentially hazardous effect if not properly understood! The problem with this design… Continue reading Laser spot size – how it changes with distance from the target…

Carbon Facial treatment with a QS Nd:YAG laser

Recently I tried the new ‘carbon facial’ treatment using the 1064nm wavelength of the Q-switched Nd:YAG laser. My wife was keen to try it! I painted a little black carbon ink solution (which I made myself) onto my wife’s face. After about 20 minutes, or so, to allow it to dry, I applied the laser… Continue reading Carbon Facial treatment with a QS Nd:YAG laser

Experiments with India ink and a Q-switched Nd:YAG laser

What happens when India ink absorbs laser energy? I irradiated some dry India ink trapped between two glass slides here (the ink was allowed to dry overnight). I used 5 J/cm^2 with a 1064 nm wavelength. As you can see, the laser energy ‘vapourises’ the ink and leaves voids behind. But, very little ink leaves… Continue reading Experiments with India ink and a Q-switched Nd:YAG laser