In previous studies maximum acquisition range was achieved when Fλ/d approached 2. There was no constraint on magnification or field-of-view. This suggested that detector size approach λ/2 when F = 1. Night vision goggles typically have a fixed FOV of 40 deg with unity magnification. Digital night vision goggles (DNVG) acquisition range is limited by the human visual system resolution of 0.291 mrad (20/20 vision). This suggests the maximum number of horizontal detectors should be about 2500 with a minimum pixel size of about 8 μm when F = 1 and aperture = 1 inch. Values change somewhat depending upon f-number and noise level. Ranges are provided for GaAs and InGaAs detectors under starlight conditions. The different spectral responses create minimum resolvable contrast (MRC) test issues.

Date Published: 3 May 2016
PDF: 5 pages
Proc. SPIE 9820, Infrared Imaging Systems: Design, Analysis, Modeling, and Testing XXVII, 98200C (3 May 2016); doi: 10.1117/12.2228529

Published in SPIE Proceedings Vol. 9820:
Infrared Imaging Systems: Design, Analysis, Modeling, and Testing XXVII
Gerald C. Holst; Keith A. Krapels, Editor(s)