Laser hair removal theory of selective photothermolysis

1) thermal relaxation time refers to the laser the target tissue after irradiation, temperature, tissue temperature decreased by 50% of the time required, both for the target tissue thermal relaxation relaxation time.
2) selective photothermal effect because the different colors of tissue has its characteristic absorption wavelength of light, therefore, according to the color of the target tissue, select the appropriate wavelength of laser energy in the right conditions, both the destruction of the target tissue, but also less than the surrounding tissue so that the thermal relaxation time, and do not cause irreversible non-therapeutic tissue damage. If hair removal , the hair shaft and hair bulb melanocytes at the laser absorption of sufficient energy, the generated heat to the surrounding hair follicles and hair bulb proliferation, when spread to the hair follicle stem cells and hair bulb of hair matrix cells, the hair regeneration of hair cells or stem cells are completely destroyed, which reached a permanent hair removal effect.