Research Progress on Absorption Properties of Oxide Optical Films

In this paper, the research progress of absorption properties of oxide optical films at home and abroad is reviewed, and the relevant absorption measurement techniques are introduced. Optical absorption loss is an important part of optical system, which can not be ignored. It seriously affects the transmission quality of the beam, the life of the device, etc. Therefore, the thin film with low absorption loss plays a very important role in large optical system and strong laser system. Oxide films have the advantages of wide band gap, high hardness, stable performance and corrosion resistance. Most optical systems use oxide materials to prepare films to improve their optical functions. The absorption of optical film is a process of interaction between light and electrons, excitons, vibration and impurity defects in the film. At present, the deposition process of optical film includes electron beam deposition technology, ion beam sputtering technology and sol-gel technology. The selection of process parameters is an important factor affecting the absorption of optical film, and other factors include temperature, heat treatment and other post-treatment technology. In addition, the measurement method of absorption coefficient is becoming more and more advanced, which also plays a key role in the control of absorption loss. With the appearance of more and more thin film materials, selecting suitable thin film materials and studying their structure and optical properties is an important link to control absorption loss.