Design And Manufacture Of The Infrared Double Wave Band Laser Filter Film

To meet the special requirements of infrared military equipment, the article developed a laser filter which made laser energy decay to 1% at 1064nm, and also an high antireflection at 3～5μm band. According to the theory of thin film coating design,use the TFC and the public coating design software, consider the special requirements of dual-band and the characteristics of coating materials to optimize the film thickness.the infrared dual-band filter membrane is coated at the multi-spectral ZnS substrate by adjusting process parameters, using electron beam vacuum deposition. With the ion source,use ion bombardment of low energy and vacuum annealing to improve the film's anti-damage threshold of thin film, the measured stress is reduced to 51MPa from 122MPa, measured by the BGS 6341 stress tester with gradient method, as well as that low energy ion bombardment used. So the stress between the substrate has been reduced significantly. This film meets the requirements of infrared military equipment.