Multispectral Short Wave Infrared Plenoptic Imaging System Free of Fixed Pattern Noise

Abstract

We propose a single-camera multispectral Short Wave Infrared (SWIR) plenoptic imaging system free of fixed pattern noise (FPN). The developed system can form, for each scene's object of interest, an in-focus noiseless 24 channels SWIR multispectral data cube. The Fourier Slice Photography Theorem is employed in the integrated multispectral light field to achieve images at a specific scene depth of focus. And, a reference-free image quality index is used for selecting the in-focus image for each scene object focal plane. Results are then compared to SWIR multispectral data cubes obtained from light fields achieved after applying to the SWIR camera a blackbody two-point calibration method. The scientific potential of the imaging system is proved by imaging thermal stressed plants at different scene depths of focus. The FPN SWIR spectral dependence is evaluated on the images digitally refocused at the farthest scene focal plane, resulting in concordance with the InGaAs FPA quantum efficiency. The lightfield (LF) system performance to naturally filter out the FPN was evaluated with a Black body (BB) reference base index, resulting in an SSIM index close to 98 % at the object image focus plane.