Aim\ To discuss the selecting principle and the processing of infrared optical materials. Methods\ The transmissivity of definite wavelength is the main selected condition

the processability should be taken care of too. The main researching method of the processing is the optimization of the auxiliary materials. Results\ Multi crystal Si is selected to transmit (1~14) μm and ZnSe is selected to transmit 10.6 μm. The researching results of the polishing abrasives

coating materials and processing technology are represented. Conclusion\ The procedure of selecting crystal material and processing technology will be universally available to infrared optical system.