We all know (I hope!!) about fluence, or energy density. This is the stuff which heats up tissues. But what is ‘power desnity’ and why is it important?
Well, power density (or ‘irradiance’ to give it its proper name) is the concentration of power in a spot size area. This is very important in all skin treatments because it directly determines what will happen in the tissues. The power density considers not only the energy and the spot size area, but also the time over which this is delivered. Hence, it combines the energy, spot size and pulsewidth of your device’s output to the skin.
I have also included the number of photons in a pulse of light – just for a bit of fun!
I hope you enjoy this,
Mike.
Mike Murphy's Blog 