Blue light is actually a kind of red and blue light treatment, in the specific operation of the clinic, generally red light and blue light in a time of irradiation, at the same time alternating treatment, sometimes you can once purely with red light irradiation, and another time with blue light irradiation. The specific cost, according to each region, unit level is not the same, the cost is different, generally about tens of dollars for treatment once. The principle is mainly through the red light or blue light irradiation to the skin, play a different therapeutic effect, for example, the blue light is mainly through the 420 nanometer band light, kill Propionibacterium acnes, play an antibacterial and anti-inflammatory effect.