Anti-Reflective Surface Structures for Third Generation Infrared Sensors

Third-generation focal plane arrays allow US Army soldiers to view high-resolution, high frame rate imagery across multiple infrared bands. To properly utilize the capabilities of these new sensors, including their high sensitivity across the SWIR, MWIR, and LWIR bands, third-generation imaging systems employ advanced optical systems with multiple refractive and reflective components. The number of surfaces, the large refractive indices of some of the infrared materials, and the large range of angular incidence associated with fast optics make it difficult to obtain multi-element infrared optical systems with high optical transmittance across a broad, multi-band spectral range. There is a need for new techniques and processes that can increase the spectral transmittance of the optical system components (infrared lenses, windows, and beamsplitters), and allow third-generation imaging systems to achieve their full potential. Nanohmics, Inc. and the Optical Structured Surfaces Laboratory at the University of North CarolinaCharlotte are working together to apply optimized random anti-reflective surface structure (rARSS) technology to address the spectral transmittance requirements associated with the optical components of third-generation imaging systems.