The standard light source illumination range of Guangzhou Shounuo Scientific Instrument Co., Ltd. is 750 to 3200 Luxes; the background color of the light source is medium gray, and its reflected light rate must be less than one-third of the incident light; Ultraviolet light source Ultra- Violet Illuminant (UV) is used to detect items using fluorescent and whitening dyes; it provides store light sources and can provide other light sources for color contrast. It can be used all-weather in printing, paint, ink, plastic, printing and dyeing and other industries involving color observation and color matching comparison.