Crystal Polarizing Devices Antireflection Coating Research

As the polarization technology development, the application range of the crystal polarizing device become more and more larger. The crystal polarizing device is based on the birefringence of crystal. Its merit is high extinction ratio, high transmission and wide wavelength. But normally the transmissivity of the crystal polarizing device is less than 90%. The 1/4 glimmer retardation plate have the interference vibration phenomenon of its transniissivity and phase retardation for the reflection on its surface. All these shortcoming will decrease the performance of the crystal polarization device.The antireflection(AR) thin film can reduce the reflection of the surface and increase the transmission. So we can improve the performance of the crystal polarization device by evaporating the AR thin film on its surface. The main two aspects in this thesis have been detailed researched as follows:1. The design,evaporate and measurement of the AR thin film on the Glan— Taylor prism, Wollaston prism.2. How do the reflective interferce on the surface effect the transmission and retardation of the 1/4 glimmer retardation plate. The Jonse matrix is deduced which contains the multireflection on the surface. The design, evaporate and measurement of AR thin film are researched.The design and evaporate of the on the crystal polarizing device have two characters as follows:1. For the low degree of hardness and the aeolotropism of the crystal, the adhensive power of the film is bad.2. We must increase the transmission of the o light and the e light at the same time when we design the AR thin film of the Wollaston prism, which is different with the normal AR thin film.The adhesive power problem between the film and the iceland crystal substrate is solved through several adhesive power testing. For the original structure of the AR film on the Wollaston prism, we find a analytic designmethod by analyzing the acting of the inner layer.All details are as following:The purpose and the significance of this thesis are given in charter one.In Charter Two, we introduced the history of the development of the optical thin film; the basic theory of the optical thin film;In Charter Three, we give the design of the Glan—Taylor prism AR thin film which include side surface and skew surface. The incident angle and the index of film which how to effect the performance of the AR thin film on the skew surface of the Glan—Taylor prism are discussed. We research the design method of the Wollaston prism's side surface and give some film structures. As to the glimmer 1/4 retardar plate,we deduce the Jones matrix which contain the multireflection on the side surface and calculate the change of the retardation and the transmissivity with the wavelength. At last, the 633nm AR thin film of retardar plate are designed.In Charter Three, firstly, we research the adhensive power of some coating materials and find the best controlling condition for evaporating. Next, we prepare several samples by using ZZS630 vacuum coating machine and measure the reflective spectrum of the AR thin film by ITV3101 spectral photometer, which include the Glan—Taylor prism, the Wollaston prism side surface and the 1/4 glimmer retardar plate. For the AR thin film on the skew surface of the Glan —Taylor prism, we establish a system to test the reflection. At last, the error of manufacture and test are qualitatively analysised.In conclusion, this paper mainly study the design method, evaporating technology and measurement of the AR thin film on the crystal polarizing. The chief innovation is as following:1.We find a analytic design method for the beam splitter polarizer and design a original structure of the film.Using the computer optimize the original structure and get the final structure of the film. Finally, the step of this kind of film is generalized.