HgCdTe-based FPAs that can be used in high neutron radiation environments were designed and fabricated by EPIR, and tests using Fermi National Accelerator Laboratory’s neutron beam confirmed that these FPAs can maintain imaging functionality while exposed to fluxes up to low-1E13 neutron per squared centimeter accumulated neutron exposure. Monte Carlo N-Particle (MCNP) simulations were used to find that the energy deposited into the HgCdTe FPA can come from not only directly impinging neutrons but also scattered neutrons and subsequently generated protons, electrons and photons, confirming that our neutron-hardened designs are also hardened against other high energy particles. To mitigate radiation damage, we redesigned the optical system of the camera using modeling and simulation by utilizing MCNP code during our camera design. By properly choosing mirror substrate material and coating as well as the corresponding optical system and the camera design, we can filter out harmful radiation flux while still collecting the MWIR signal with high efficiency, thereby significantly reducing camera and image system performance degeneration under high-energy high-flux neutron beams.
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