Abstract

Laser-based optical diagnostics, such as planar laser-induced fluorescence and, especially, Raman imaging, often require selective spectral filtering. We advocate the use of an imaging spectrograph with a broad entrance slit as a spectral filter for two-dimensional imaging. A spectrograph in this mode of operation produces output that is a convolution of the spatial and spectral information that is present in the incident light. We describe an analytical deconvolution procedure, based on Bayesian statistics, that retrieves the spatial information while it avoids excessive noise blowup. The method permits direct imaging through a spectrograph, even under broadband illumination. We introduce the formalism and discuss the underlying assumptions. The performance of the procedure is demonstrated on an artificial but pathological example. In a companion paper [Appl. Opt. 43, 5682–5690 (2004)] the method is applied to the practical case of fuel equivalence ratio Raman imaging in a combustible methane–air mixture.

© 2004 Optical Society of America

Quantitative imaging through a spectrograph. 2. Stoichiometry mapping by Raman scattering

René A. L. Tolboom, Nico J. Dam, and Hans ter Meulen
Appl. Opt. 43(30) 5682-5690 (2004)

Quantitative spectrally resolved imaging through a spectrograph

René A. L. Tolboom, NicoJ. Dam, Nanna M. Sijtsema, and J. J. ter Meulen
Opt. Lett. 28(21) 2046-2048 (2003)

Proposal for aberration-corrected imaging spectrograph

Tetsuo Iwata and Hideho Hisada
Appl. Opt. 36(28) 7114-7118 (1997)

Imaging spectrograph for interstellar shocks: a narrowband imaging payload for the far ultraviolet

Matthew Beasley, Catherine Boone, Nathaniel Cunningham, James Green, and Erik Wilkinson
Appl. Opt. 43(24) 4633-4642 (2004)

Panchromatic spectrograph with supporting monochromatic imagers

A. L. Broadfoot, B. R. Sandel, D. Knecht, R. Viereck, and E. Murad
Appl. Opt. 31(16) 3083-3096 (1992)