The actual fact is that there are a lot of people who are not able to get a good deal on this kind of things. The study found that the starting wavelength of light that causes cancer in human skin is short wavelength light below 299nm, the cause of cancer is the damage caused by short wavelength light below 299nm to DNA after causing mutation of cells. The 308nm excimer light therapy machine we are currently using is loaded with harmful light precision filter, which enables us to obtain high radiation dose at the level of the smallest red spot, and at the same time, avoid the damage of harmful light to DNA to the maximum extent, so as to obtain the highest treatment effect and the lowest side effect. We traditionally use narrow-wave ultraviolet light to treat vitiligo very many times, even hundreds of treatments, and with limited efficacy, while most patients treated with 308 light can generally achieve more than 75% complete clearance in 2-4 sessions.