Study of Triple Band Antireflection Coating Simultaneously Effective in Visible, Nd-YAG and Eye Safe Laser Wavelength

摘要

Triple band high efficiency antireflection coating effective in visible region for sighting system, Nd-YAG laser wavelength for designating system and eye safe laser wavelength for ranging purpose can use common objective/receiver optics highly useful for state of art laser instrumentation. In this paper, design and fabrication of antireflection coating simultaneously effective in visible region (500 to 600nm), Nd-YAG laser at 1064±25nm, and erbium-glass laser wavelength at 1535±25nm has been reported. Comprehensive search method of design was used without a starting design. The fourteen-layer stack designed for the antireflection coating has been fabricated by using electron beam gun evaporation system in Blazers BAK-600 vacuum coating unit. The result achieved were 98% average transmission from 500 to 600nm, 99.5% average transmission at 1064±25nm and 99.5% average transmission at 1535±25nm. The coated samples successfully passed the specifications of MIL-C-13508 tests.