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Title: Kilohertz frame rate snapshot hyperspectral imaging of metal reactive materials

We demonstrate a kilohertz frame rate snapshot hyperspectral imaging system suitable for high-speed imaging, which we name snapshot hyperspectral imager for emission and reactions (SHEAR). This system splits the sensor of a single high-speed camera to simultaneously capture a conventional image and a spectrally sheared response of the scene under study. Given the small, point-source-like nature of burning metal micro-particles, the spectral response of the species is captured without the need for a slit, as is needed in conventional imaging spectrometers. We pair robust image registration techniques with sparse reconstruction algorithms to computationally disentangle overlapping spectra associated with many burning particles over the course of a combustion experiment. As a proof-of-concept experiment, representative physical vapor deposited Al:Zr composite particles are ignited, and their burn evolution is recorded at a frame rate of 2 kHz using this method. We demonstrate operation over two distinct wavelength ranges spanning hundreds of nanometers in wavelength and with sub-nanometer resolution. We are able to track hundreds of individual Al:Zr particles in a single high-speed video, providing ample statistics of burn time, temperature, and AlO emission timing in a high-throughput method. The demonstrated technology is high-throughput, flexible in wavelength, inexpensive, and relatively easy to implement, and provides a much needed tool forin situcomposite metal fuel diagnostics.

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Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Applied Optics
1559-128X; APOPAI
Page Range / eLocation ID:
Article No. 10406
Medium: X
Sponsoring Org:
National Science Foundation
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