GB/T 24370-2021 Focusing on the field of nanotechnology, it stipulates that the UV-visible absorption Light spectrum method is used to characterize the colloidal quantum point of cadmium chalide. The standard details the sample preparation method to ensure the uniformity and stability of the quantum point solution. The operation process of the Light spectrum instrument is described, including Wavelength range setting, scanning speed and other parameters. By analyzing the characteristics of the absorption Light spectrum, such as the position and intensity of the absorption peak, key information such as quantum point size and concentration can be accurately obtained, which provides an important basis for the quality control and performance evaluation of cadmium chalide colloidal quantum points in the research and production of nanomaterials.