Study on the anti-reflection technology of color separate gratings

Because of the reflection on the surface of the gratings, the diffractive efficiency of the components cannot meet the requirement of the ICF system. To solve the problem this paper introduces a kind of scheme adopted coating to reduce the reflection of the gratings' surface. The coating anti-reflection technology of the CSG is discussed. Using the scalar theory the design parameters wwere decided and the structure parameters of the gratings were optimized. The optimized value of the trough depth of the CSG is 2.84 μm, and the optimized value of the film depth is 71.2 nm. The numerical results show that the reflection of the gratings' surface was eliminated drastically. The validity of the anti-reflection technology is distinctly in the application of the high power laser propagation.