Introduction
ND YAG laser emits a laser beam of a specific wavelength that can accurately penetrate the skin layer and reach the location of pigment particles in the dermis. Pigment particles have the characteristic of selectively absorbing lasers of specific wavelengths. After absorbing laser energy, the temperature of the location of the pigment particles will rise sharply in an instant, generating extremely high temperatures, causing the pigment particles to expand and break. The broken pigment particles will be killed by macrophages in the body, and then eliminated from the body as the body smears them, thereby achieving the pigment effect
