Hi
We have a flame detector designed for outdoor use, using pyro sensors that view through a sapphire window. The window is a 3mm thick rectangle, elastomer-bonded behind an (essentially) arch-shaped window and secured using a screwed steel back-plate - acoustically quite a complex shape. The operating environment has contaminants varying from rain, fog, sea-mist, frost/ice, with dust, oil, bird-sh*t etc. We would like to discuss our application further...!
Best regards
Dave Randall