The hair is mainly composed of keratinocytes that synthesize keratin, and melanocytes which are responsible for the production of melanin. In photo-depilation, intense pulsed light is absorbed by the melanin (coloured pigment) contained in the hair. This is then channeled to the “root” (hair shaft, hair follicle, epithelium and matrix). When the light meets a chromophore, it is converted into heat; the thermal effect destroys the germ cells responsible for hair growth. These are located approximately 4-6mm under the skin.  Hair acts as a conductor of energy to these cells, therefore, the hair must be in the “anagen” phase (phase at which the bulb and the hair shaft are attached to the root). Dark skin contains a higher concentration of melanin. From the cornea layer, the skin can act as a competitive chromophore when targeting the melanin in the hair. The specific filtration for dark skin (phototype IV, V and the begining of VI) promotes the absorption of the pulsed light by melanin contained in a hair anchored in tissue, and thus leads to a high level of effiency of the treatments. A specific filtration is necessary up to 690 nanometres, and is limited in exposure using a range of wavelengths from 420 to 690nm which allows the destruction of the bulb, while preserving the skin.

The multipulsed mode is an important parameter that reflects the TRT (Thermal Relaxation Time) of the skin which is relative to the target chromophore which avoids the risk of burns caused by single flashes that are too long. To completely preserve dark skin during hair removal treatments it is necessary to increase the number of pulses, reduce the pulse duration and increase the interval between pulses

The accumulation of exposure to the sun, smoking, general pollution and aging are accompanied by age related distortion of the structural components of the skin. Fibroblasts, which are one of the main types of cells found in the connective tissue of the dermis, are responsible for the renewal of collagen and elastin. The natural production of collagen starts to decrease from the age of 25 and it further declines from the age of 40. It is important to stimulate cell renewal to prevent the skin from aging in order to take anti-aging action. Intense pulsed light emits the flash of pulsed light at a wavelength of 535nm allowing the stimulation of fibroblast cells. This thermal denaturation of collagen induces neo-collagenesis ; the inflammatory response that results from heating the skin creates a cascade of reactions leading to the synthesis of collagen.

Using IPL for skin rejuvenation stimulates the production of collagen and elastin. There is also an improvement in skin elasticity, reduced pore size and a reduction in fine lines. The skin is radiant and toned, the face is reshaped and the skin texture is improved. The results are visible from the first session.