Diffractive optical systems in the Infrared (IR) wavelength regime are being re-examined for remote sensing applications. A pupil-plane adaptive coded aperture can enable a fine resolution, wide field of view sensor system without mechanical scanning. Due to the relatively long wavelengths, coded aperture systems in the IR have unique issues in regards to e.g. X-ray coded apertures. These include diffraction effects, wavelength dependence of optical elements, off axis aberrations due to thick screens, etc. In this paper, we provide a general system model framework based on partial coherence theory that enables us to explore many of the technical challenges in IR diffractive imaging. This paper develops the general theory and shows examples of issues that impact the optical transfer function (OTF) and impulse response of these types of architectures.

Date Published: 26 September 2007
PDF: 12 pages
Proc. SPIE 6714, Adaptive Coded Aperture Imaging and Non-Imaging Sensors, 67140F (26 September 2007);

Published in SPIE Proceedings Vol. 6714:
Adaptive Coded Aperture Imaging and Non-Imaging Sensors
David P. Casasent; Timothy Clark, Editor(s)