... waves 3) 2 BIO waves 4) LCD screen led light therapy IntroductionPhototherapy has long history, the ancient Greek, ancient ... showing luster. It provides a safety and non-intrusive method for different status of skin.Light classification1. The sunlight includes a ... lot of lights of different wave-lengths, there are infrared light, visible light (imply red, orange, yellow, green, black, orchid, purple ...