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Updated: Mar 26, 2026

Differential Imaging of Biological Structures with Doubly-resonant Coherent Anti-stokes Raman Scattering CARS
Published on: October 17, 2010
Pure electrical, highly-efficient and sidelobe free coherent Raman spectroscopy using acousto-optics tunable filter
Zhaokai Meng1, Georgi I Petrov1, Vladislav V Yakovlev1
1Texas A&M University, College Station, TX, 77843, United States.
Abstract:
Fast and sensitive Raman spectroscopy measurements are imperative for a large number of applications in biomedical imaging, remote sensing and material characterization. Stimulated Raman spectroscopy offers a substantial improvement in the signal-to-noise ratio but is often limited to a discrete number of wavelengths. In this report, by introducing an electronically-tunable acousto-optical filter as a wavelength selector, a novel approach to a broadband stimulated Raman spectroscopy is demonstrated. The corresponding Raman shift covers the spectral range from 600 cm(-1) to 4500 cm(-1), sufficient for probing most vibrational Raman transitions. We validated the use of the new instrumentation to both coherent anti-Stokes scattering (CARS) and stimulated Raman scattering (SRS) spectroscopies.
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