Label-free hyperspectral dark-field microscopy towards quantitative scatter imaging
Philip Cheney, David McClatchy III, Stephen Kanick, Paul Lemaillet, David W. Allen, Daniel V. Samarov, Brian Pogue, Jeeseong Hwang
A hyperspectral dark-field microscopy technique has been developed for imaging spatially distributed diffuse reflectance spectra from light-scattering samples. In this report, quantitative scatter spectroscopy was demonstrated with a uniform scattering phantom, a solution of polystyrene microspheres. A Monte Carlo-based inverse model was used to calculate the reduced scattering coefficients of the samples of different microsphere concentrations from wavelength-dependent backscattered signal measured by the dark-field microscopy. The result was compared with the measurement result by a NISTs double integrating sphere system for validation. Ongoing efforts involve quantitative mapping of scattering and absorption coefficients in samples with spatially heterogeneous optical properties.