Enhancement of CASSI by a zero-order image employing a single detector

TL;DR

This paper introduces a novel CASSI system capturing both spectrally sheared and integrated images with a single detector, significantly enhancing reconstruction quality and speed while simplifying the system.

Contribution

It presents a new CASSI approach using a zero-order image, reducing system complexity and improving hyperspectral data reconstruction from a single camera.

Findings

Use of non-diffracted image improves data reconstruction.

Spectrally integrated image enhances reconstruction quality.

Reconstruction time reduced by approximately five times.

Abstract

Coded aperture snapshot spectral imaging (CASSI) makes it possible to recover 3D hyperspectral data from a single 2D image. However, the reconstruction problem is severely underdetermined and efforts to improve the compression ratio typically make the imaging system more complex and cause a significant loss of incoming light intensity. In this paper, we propose a novel approach to CASSI which enables capturing both spectrally sheared and integrated image of a scene with a single camera. We performed hyperspectral imaging of three different testing scenes in the spectral range of 500-900 nm. We demonstrate the prominent effect of using the non-diffracted image on the reconstruction of data from our camera. The use of the spectrally integrated image improves the reconstruction quality and we observed an approx. fivefold reduction in reconstruction time.