蓝宝石头罩增透保护膜系的制备

Infrared anti-reflective films have been designed on sapphire and their film thickness uniformity was optimized by simulation calculations. Rain erosion tests of sapphire witness pieces were carried out on a whirling arm rig. Simulation results show that the thickness non-uniformity of SiO2 films was less than 8.5% over the convex surface of a dummy dome. After rain erosion test, the average transmission loss on all the coated pieces was less than 1%. After the coating passed the rain erosion test, SiO2 coatings have been prepared on sapphire domes by radio frequency magnetron sputtering. The average transmission of sapphire domes coated on convex surfaces can be increased to more than 91.0% at wavelengths from 3 to 5 μm. The transmission non-uniformity over the convex surface of the coated sapphire dome was less than 2.0%. The transmission results of the coated domes are satisfied and it could meet the requirement in application.