The Q-Switch ND: YAG laser delivers light of specific wavelengths with high energy which are absorbed by the pigment and results in a shockwave. The Shockwave shatters the pigment particles, releasing them from their encapsulation and breaking them into tiny fragments and then eliminated out of the body. Since this specific wavelength can only be absorbed by pigment particles, no injury to skin and normal tissues will occur. The machine utilizing the explosive effect of the ND: YAG LASER, the laser permeates the epidermis into the dermis and takes effect on pigment mass and is absorbed by pigment. Since the laser pulses are extremely short in nanosecond and come with super high energy, the pigment mass would swell quickly and break into small pieces, which will be eliminated through metabolism. In this case, the pigments become lighter gradually and finally disappear.