Development of Infrared Dual-band Antireflection Coating for Automotive Chalcogenide Glass Elements

Based on the chalcogenide glass IRG206 (As₄₀Se₆₀) substrate, 3.7−4.8 μm and 7.5−9.5 μm dual-band antireflection coatings were developed, which can be used in automotive infrared night-vision imaging systems. Using electron beam and resistance evaporation ion-assisted deposition technology, combined with chemical bond analysis, the connecting layer material was selected to improve the adhesion between the substrate and film layer. Ion-assisted stress control technology was used to optimize the stress of the film layer and realize the matching of the stress of the film layer, to solve the problem of chalcogenide glass stripping. In test results, the average transmittance of the film layer in the 3.7−4.8 μm and 7.5−9.5 μm bands was 98.31% and 97.43%, respectively, passing environmental tests such as firmness, salt spray, high and low temperature, and abrasion, thereby satisfying the requirements of the automotive infrared night-vision imaging system.