Solar energy collector is a device that converts solar energy into heat energy. It plays an important role in solar energy refrigerator system. Its efficiency and price will directly affect the efficiency and economy of the whole solar energy refrigerator. In order to improve the efficiency of solar collectors, most of the current researches are limited to the improvement of the structure of the absorber and the concentrator, while the research on the nature of heat absorption of the collector is less. The essence of heat absorption is reflected in the optical properties of materials, that is, the ability to absorb light in a certain band. , therefore, the author thinks that, the absorber and the surface absorption coating material development will be the key to improve the efficiency of solar collector fridge, there is a lot to improve on technology and development, such as solar radiation on heat absorber surface coating has the very high spectral absorption ratio of coating, to keep the maximum gathering solar radiant energy; Or select the heat absorbing surface material reasonably according to the radiation characteristics of the material so that its spectral absorption ratio in the wavelength range of 0.3~3 muon is close to 1.