The biological light source used in the elf phototherapy instrument has been protected by relevant patents, which further proves its uniqueness and innovation. Adopt high-performance LED light source, and realize the accurate and rapid adjustment and improvement of shape perception, light perception and color perception through secondary optical treatment like lumen. In addition, the customized spectrum of this product can supplement the peripheral light nutrition of retina through diffuse reflection, improve the oxygen carrying capacity around eyes, promote the secretion of tears, supplement enough eye light nutrition for children, and have a very positive impact on the prevention and control of myopia.