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arXiv · 2006.08565

Spectral DiffuserCam: lensless snapshot hyperspectral imaging with a spectral filter array

Kristina Monakhova·Kyrollos Yanny·Neerja Aggarwal·Laura Waller
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Abstract

Hyperspectral imaging is useful for applications ranging from medical diagnostics to agricultural crop monitoring; however, traditional scanning hyperspectral imagers are prohibitively slow and expensive for widespread adoption. Snapshot techniques exist but are often confined to bulky benchtop setups or have low spatio-spectral resolution. In this paper, we propose a novel, compact, and inexpensive computational camera for snapshot hyperspectral imaging. Our system consists of a tiled spectral filter array placed directly on the image sensor and a diffuser placed close to the sensor. Each point in the world maps to a unique pseudorandom pattern on the spectral filter array, which encodes multiplexed spatio-spectral information. By solving a sparsity-constrained inverse problem, we recover the hyperspectral volume with sub-super-pixel resolution. Our hyperspectral imaging framework is flexible and can be designed with contiguous or non-contiguous spectral filters that can be chosen for a given application. We provide theory for system design, demonstrate a prototype device, and present experimental results with high spatio-spectral resolution.

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Kristina Monakhova, Kyrollos Yanny, Neerja Aggarwal, Laura Waller. 2020-09-29. Spectral DiffuserCam: lensless snapshot hyperspectral imaging with a spectral filter array. https://doi.org/10.1364/optica.397214

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