What is the difference between Peninsula 308 and 311 developed by Peninsula Medical Group

Peninsula home 308 light therapy instrument is excimer light, 311 is narrow-spectrum UVB, the difference between the two kinds of light is: excimer light is a single wavelength, does not contain stray light; 311 contains other ineffective stray light, lower energy, so the Peninsula home 308 light therapy instrument is higher in energy, shorter irradiation time, the effect will be a little bit better