The inner wall of the integrating sphere is coated with a layer of white coating, the white coating is used for diffuse reflection of light to ensure that the inner wall of the integrating sphere is not polluted or not polluted, so that it always maintain high diffuse reflectance is very important, because the light emitted by the lamp component of the instrument first passes through the diffuse reflection of the inner wall of the integrating sphere, so that the inner wall of the integrating sphere is not polluted or not polluted. Therefore, it is very important to always maintain a high diffuse reflectance, because the energy of the light emitted by the instrument's beam component through the inner wall of the integrating sphere will be greatly reduced, such as the correction pass or the data is inaccurate. Therefore, the maintenance of the integrating ball is very important, and it is also the key to ensure the long-term stable operation of the integrating ball structure