Antireflective and protective films consisted of GexC1-x films were prepared by reactive radio frequency magnetron sputtering (RRFS) on ZnS dome. A computer was used to simulate the thickness distribution of the film of ZnS dome for different movement tracks, and the best one was got by using the best dome movement track. The thickness uniformity of films could meet the application requirement when films were deposited by RRFS on the dome. The computer control system was built according to the simulation results, and antireflective and protective films consisted of GexC1-x films were deposited on the ZnS dummy dome. The results show that 1) the variation of thickness is lower than 10%, 2) the average transmittance, in the 8～11.5μm waveband, is raised from 69.6% to above 87.2% after the films are coated on double sides, 3) the average transmittance variation is less than 1.2%. Thus the requirements of ZnS dome in infrared application are met.