PDT beauty machine offer a natural, non-ablative method for skin rejuvenation. The light from the PDT interacts with cells and stimulates them to produce new collagen and elastin bio light therapy.Studies confirm that the same PDT energy can be used to inhibit collagen formation, which can be helpful in the treatment of scars. By manipulating the wavelengths, cells can be turned on and off. Yellow light are used for photo-rejuvenation. Blue light are used in the treatment of acne. Red light are used for photo dynamic therapy, green Light effective reduce melanin cell,decreased pigment formation.