Excimer Laser – Excimer UV-light is a single-rate excimer light by using XeCl as illumination, to induce T cells apoptosis and improve pigment synthesis. Short treatment time can be more accurate for the skin treatment. Its single 308nm wave length is considered as the best one to treat Vitiligo and Psoriasis. It is also regarded as the most effective way to treat Vitiligo, Psoriasis and other skin diseases because of the high energy, single wave length, excellent efficacy, short treatment course and less adverse reactions.