Intermediate image free computed tomography imaging spectrometer

Abstract

The Computed Tomography Imaging Spectrometer (CTIS) is a snapshot hyperspectral camera based on computational imaging. Typical designs use a Keplerian beam expander to limit the imaged scene and decrease the incident ray angles. We have found that the use of a Galilean beam expander instead can be beneficial. Often a smaller system with a better optical quality is achievable with the disadvantage of a vignetted image. Results of a comparison between both designs based on a prototype will be shown. Furthermore, we present our miniaturized CTIS system, which uses the Galilean design.

Parallelized computed tomography imaging spectrometer

“…It can be built with less optical elements and a possible smaller form factor. 14 However, since the system has no intermediate image plane, the captured field must be limited by a field stop in front of the system. The field stop is out of focus, resulting in a vignetted hyperspectral image.…”