Study On High Temperature Resistantance Of Optial Window For Anti-reflection Applications

At present, the quartz is one of the most commonly used optical window materials and there is a wide range of applications in the display window, solar, camera lens and photoelectric detector etc. The surface has a greater reflection due to the existence of refractive index mismatch between air and base material. Single layer and multi- layer optical thin film is a commonly used method to reduce surface reflection. However, this method has the problems of thermal mismatch, choice of ma terials and instability. With the development of optical thin films using the environment more and more complex, the stability of the surface structure of optical windows in different thermal loads has become a very important problem.Sub-wavelength structure originates in the "moth eye" micro lens structure. At present, there are a variety of methods used to build the antireflective subwavelength structure. But these methods exist some disadvantages, such as expensive equipment, low efficiency and it is difficult to realize large area preparation etc..Considering, whether or not the actual structure is ordered, it has little effect on the surface anti-reflection property. Therefore, it can simplify the operation process, and effectively reduce the cost and time, if the disordered mask replaces an ordered mask. Subsequently, self-assembled nanopatterns that can be used as etching masks were patterned by etching method.The main content of the paper is divided into two parts.On the one hand, the high and low refractive index material, such as Ti O2, Ta2O5, Al2O3 and Si O2 films were prepared by ion sputtering method. The evolutions of micro-structure, stress and optical performance is investigated by the heat treatment method. Research shows that Ta2O5 and Si O2 thin film structure is relatively stable. There are no obvious surface damage morphologies after heat treatment. The factors that affect the structure stability of Ti O2 thin film is very complex, and it is closely related to the micro structural defects, film crystallization and so on. When the temperature exceeds 800 degrees, the optical performance of multi- layer Ta2O5/Si O2 film will cause serious degradation due to the effect of structural transition, crystal.On the other hand, the paper theoretically has analyzed the effects of the basic parameters and the stochastic distribution on the zero order diffraction efficiency. Through the method of self-assembled nano- metal masks, we optimize the Au, Ag nanopatterns and the antireflective microstructures are obtained in quartz window using the reactive ion beam etching technique. Further, we test and analysis the performance of high temperature resistant. Related research results can provide a better guidance for the design of antireflective subwavelength structure, processing technology and performance study.