Using new optical materials and DOE in low-cost lenses for uncooled IR cameras

Angenieux recently developed a low cost 100 mm F/1.25 lens for uncooled IR cameras. It is made of only 2 elements, thanks to the use of GASIR glass (Umicore product) and a diffractive surface. With regard to its equivalent in germanium, it offers similar performances, for a much lower cost due to the price of the optical material, molding, and no need for athermalisation. This lens can be used with new light-weighted night vision goggle ELVIR developed by Thales-Angenieux. We plan to also use GASIR in low cost zoom lenses for uncooled cameras. Starting with these examples, we will compare different available optical materials for IR, their characteristics, and respective advantages and drawbacks. We will deduct from it from rules of use for these materials, depending upon the envisaged use, spectral bandwidth and number of items manufactured.