Ternary parallel beam splitter combined of iceland and glass

In order to save the rare iceland and increase the shear difference,a new type of parallel beam splitter combined of iceland and glass is designed.The prism is made of ZBaF3 glass,between which is iceland.The glue is C10H7Br with high refractive index.It can be approved by the theory and experiment that the extinction ratio of the parallel beam splitter is better than 10-3,and the shear difference is improved too.