Fourier Transform Light Scattering (FTLS)

Posted on March 2, 2012 by admin

Fourier transform light scattering (FTLS) is a novel experimental approach that combines optical microscopy, holography, and light scattering for studying inhomogeneous and dynamic media. In FTLS the optical phase and amplitude of a coherent image field are quantified and propagated numerically to the scattering plane. Because it detects all the scattered angles (spatial frequencies) simultaneously in each point of the image, FTLS can be regarded as the spatial equivalent of Fourier transform infrared spectroscopy (FTIR), where all the temporal frequencies are detected at each moment in time. So far FTLS has been used to study various cell types and tissues.

 

 

 

 

 

 

 

 

 

Following from FTLS. We have also derived two mathematical relations between quantitative phase images of thin slices of inhomogeneous media and the scattering parameters of the bulk, i.e., scattering mean free path, ls, and anisotropy factor, g. The ls turns out to be inversely proportional to the spatial variance of the phase shift, and g is related to the variance of the phase gradient. These formulas, referred collectively to as the scattering-phase theorem, allow for extracting ls and g in a spatially resolved manner and across an entire tissue section, that is, mapping large cross sections of tissues in terms of ls and g.

 

 

 

Relevant Publications

  1. J. Lim, H. Ding, M. Mir, R. Zhu, K. Tangella and G. Popescu, Born Approximation Model for Light Scattering by Red Blood Cells, Biomed. Opt. Exp., 2 (10), 2011.
  2. Z. Wang, H. Ding, and G.Popescu,Scattering-phase theorem, Opt. Lett., 36(7) (2011).
  3. H. F. Ding, E. Berl, Z. Wang, L. J. Millet, M. U. Gillette, J. M. Liu, M. Boppart and G. Popescu , Fourier Transform Light Scattering of Biological Structure and Dynamics, IEEE Journal of Selected Topics in Quantum Electronics.
  4. H.Ding, L.J Millet, M.U. Gillette and G. Popescu, Actin-driven cell dynamics probed by Fourier transform light scattering, Biomed. Opt. Exp., 1 (1), (2010).
  5. H. Ding, F. Nguyen, S. A. Boppart and G. Popescu, Optical properties of tissues quantified by Fourier transform light scattering, Opt. Let., 34, 1372 (2009).
  6. H. Ding, Z. Wang, F. Nguyen, S. A. Boppart, and G. Popescu, Fourier transform light scattering of inhomogeneous and dynamic structures, Phys. Rev. Lett., 101, 238102 (2008).