laser Selective photothermolysis

What’s selective photothermolysis?

Selective photothermolysis (Part 2) Melanin absorbs across a wide spectrum of wave-lengths. Eumelanin, the primary chromophore in the epi-dermis and darkly pigmented hair follicles, has a broad absorption spectrum spanning from ultraviolet light to the near-infrared region. Eumelanin is the chromophore targeted in lentigo simplex. It is also the target in laser hair removal with…

laser Selective photothermolysis

What’s selective photothermolysis?

Selective photothermolysis (part 1) SP relies on fundamental choices being made correctly – wavelength, pulse duration, fluence, exposure spot size, and use of skin cooling. First, a wavelength (or, with IPLs, a range of wavelengths) must be used that is preferentially absorbed by the intended ‘target’ structures such as hair follicles, microvessels, tattoo inks, or…

Light interactions with skin

Light interactions with skin Photons can be absorbed (giving up their energy to matter) or scattered (changing their direction of travel). Light that is scattered back from skin is called reflectance. For a given skin layer, light that passes through it is called transmittance. Scattering is inversely wavelength depen-dent, such that shorter wavelengths are scattered…