As light is measured in nanometres; the depth at which the L.E.D. (Light Emitting Diodes) penetrates is governed by the attraction to the moisture within the skin, by way of blood, melanin and moisture. This is why there are different light colours for different treatment results, as the moisture attracts the colours to different depths of the skin.
For example:
Red light – penetrates the deepest to assist with anti-ageing as it stimulates collagen and elastin firming and toning the skin.
Blue light – works on acne bacteria, killing off the culprit for pimples, pustules and infection, speeding up the healing time and minimising scarring.
Green light – works on melanin as it assists in cell turnover and inhibits the excess production of melanin which we see on the skin as pigmentation.