The reduced Rayleigh scattering of SWIR radiation, when compared to the visible and NIR band, can be exploited to obtain higher contrast images even under challenging atmospheric conditions. Additionally the SWIR band neatly covers the most popular wavelengths used for laser designation and ranging, and hence SWIR imagers can be used to target and detect these sources. A SWIR sensor can also be used in night vision applications by taking advantage of an atmospheric phenomenon called night sky radiance (or night glow) that emits five to seven times more illumination than starlight, nearly all of it in the SWIR wavelengths. This paper presents a radiometry model intended for the design and analysis of a SWIR imaging sensor that is expanded to included night-time scenarios and laser “see-spot” range performance. The model is also adapted for input variable compliance with the industry standard NV-IPM range performance model, thereby enabling cross-correlation between the range performance predictions of the two models’ results. Some SWIR sensor design examples that trade off the imaging range performance and the “see-spot” range performance are presented, and the results are discussed.

Date Published: 14 May 2019
PDF: 19 pages
Proc. SPIE 11001, Infrared Imaging Systems: Design, Analysis, Modeling, and Testing XXX, 1100105 (14 May 2019); doi: 10.1117/12.2518923

Published in SPIE Proceedings Vol. 11001:
Infrared Imaging Systems: Design, Analysis, Modeling, and Testing XXX
Gerald C. Holst; Keith A. Krapels, Editor(s)