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PubMed · 12885030

Fourier-domain low-coherence interferometry for light-scattering spectroscopy.

Adam Wax·Changhuei Yang·Joseph A Izatt
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Abstract

We present a novel method for obtaining depth-resolved spectra for determining scatterer size through elastic-scattering properties. Depth resolution is achieved with a white-light source in a Michelson interferometer with the mixed signal and reference fields dispersed by a spectrograph. The spectrum is Fourier transformed to yield the axial spatial cross correlation between the signal and reference fields with near 1-microm depth resolution. Spectral information is obtained by windowing to yield the scattering amplitude as a function of wave number. The technique is demonstrated by determination of the size of polystyrene microspheres in a subsurface layer with subwavelength accuracy. Application of the technique to probing the size of cell nuclei in living epithelial tissues is discussed.

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Fourier AnalysisInterferometryLightModels, TheoreticalScattering, RadiationSpectrum AnalysisJournal Article

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Adam Wax, Changhuei Yang, Joseph A Izatt. 2003-07-15. Fourier-domain low-coherence interferometry for light-scattering spectroscopy.. https://doi.org/10.1364/ol.28.001230

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