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Spectral structure of laser light scattering revisited: bandwidths of nonresonant scattering lidars

Chiao-Yao She
2001 Applied Optics  
Revisiting the correct name by distinguishing Cabannes scattering from Rayleigh scattering, and sharpening the definition of each scattering component in the Rayleigh scattering spectrum, the review allows  ...  ., Mie, aerosol-wind, Rayleigh, high-spectral-resolution, molecular-wind, rotational Raman, and vibrational Raman lidars, are workhorses for probing atmospheric properties, including the backscatter ratio  ...  polarizability tensor elements ␣ and ␥ can be calculated from quantum theory 16 and scattering cross sections can then be estimated.  ... 
doi:10.1364/ao.40.004875 pmid:18360530 fatcat:7xczdnricrfgnisj6zrk7xroma

Robust concentration determination of optically active molecules in turbid media with validated three-dimensional polarization sensitive Monte Carlo calculations

Daniel C�t�, I. Alex Vitkin
2005 Optics Express  
It is shown that the orientation of the polarization of the scattered light exhibits a strong dependence on exit position in the side or backscattered directions, but not in the forward direction.  ...  In addition, it is shown that the increased path length of photons due to multiple scattering in a 1 cm cuvette filled with forward-peaked scatterers (anisotropy around 0.93) increases the optical rotation  ...  (essentially the Q coefficient of the Stokes vector).  ... 
doi:10.1364/opex.13.000148 pmid:19488339 fatcat:aapiumpfnnfivn5cwo2g76endu

Submicron scale tissue multifractal anisotropy in polarized laser light scattering

Nandan Kumar Das, Rajib Dey, Semanti Chakraborty, Prasanta K Panigrahi, Igor Meglinski, Nirmalya Ghosh
2018 Laser Physics Letters  
We have thus developed an inverse analysis method for the quantification of the multifractal anisotropy from the scattering Mueller matrix.  ...  Sensing structural anisotropy in the sub-micron length scale via the multifractal anisotropy parameters may prove valuable for non-invasive characterization of a wide class of complex materials and disordered  ...  Acknowledgements This work was supported by IISER-Kolkata, an autonomous institute funded by MHRD, Govt. of  ... 
doi:10.1088/1612-202x/aa86f2 fatcat:rnl7w5wigrfbdnlwoeaexvqqqq

Depolarization of light in turbid media: a scattering event resolved Monte Carlo study

Xinxin Guo, Michael F. G. Wood, Nirmalya Ghosh, I. Alex Vitkin
2010 Applied Optics  
The Monte Carlo simulations also confirm that depolarization is not only controlled by the number of scattering events and detection geometry, but is also strongly influenced by other factors such as anisotropy  ...  Larger detection angles, close to backscattering direction, show lower full depolarization threshold number for a given set of sample's optical properties.  ...  The authors thank the Natural Sciences and Engineering Research Council of Canada (NSERC) for financial support of this research.  ... 
doi:10.1364/ao.49.000153 pmid:20062501 fatcat:wlaruiddxfemtonhecxk5evxwe

Tissue polarimetry: concepts, challenges, applications, and outlook

Nirmalya Ghosh
2011 Journal of Biomedical Optics  
Specifically, we discuss polarized light basics, Stokes-Muller formalism, methods of polarization measurements, polarized light modeling in turbid media, applications to tissue imaging, inverse analysis  ...  in terms of accurate measurements and in terms of analysis of the tissue polarimetry signal.  ...  [18] [19] [20] [21] ( I R − I L ⎤ ⎥ ⎥ ⎥ ⎥ ⎦ , (1) where I, Q, U, and V are Stokes vector elements.  ... 
doi:10.1117/1.3652896 pmid:22112102 fatcat:i7cmk3ub7fb4zercxybjj3qfza

Spin-flip and acoustic-phonon Raman scattering in CdS nanocrystals

A. A. Sirenko, V. I. Belitsky, T. Ruf, M. Cardona, A. I. Ekimov, C. Trallero-Giner
1998 Physical Review B (Condensed Matter)  
The effective electron g factor has been measured as a function of the quantum dot size.  ...  We discuss both the spin-flip and the acoustic-phonon Raman spectra on the basis of the interaction of size-quantized electronic excitations with nonconfined acoustic vibrations.  ...  , while the matrix element R(q,a*) is almost independent of q.  ... 
doi:10.1103/physrevb.58.2077 fatcat:gjefb73rw5bxdp4ydx4hrweev4

Polarisation optics for biomedical and clinical applications: a review

Chao He, Honghui He, Jintao Chang, Binguo Chen, Hui Ma, Martin J. Booth
2021 Light: Science & Applications  
In this review, we focus mainly on summarising methodologies and applications related to tissue polarimetry, with an emphasis on the adoption of the Stokes–Mueller formalism.  ...  Various advanced vector measurement/sensing techniques, physical interpretation methods, and approaches to analyse biomedically relevant information have been developed and harnessed.  ...  Despite containing four elements, a Stokes vector contains fewer than four degrees of freedom due to physical constraints.  ... 
doi:10.1038/s41377-021-00639-x pmid:34552045 fatcat:ihgale2iqvdxth32pdt6xz4kdu

Polarized light interaction with tissues

Valery V. Tuchin
2016 Journal of Biomedical Optics  
This theory employs the modified transfer equation for Stokes parameters to predict the polarization properties of single-and multiple-scattered optical fields.  ...  Examples of biomedical applications of these techniques for early diagnostics of cataracts, detection of precancer, and prediction of skin disease are presented.  ...  This study was supported in parts by grants 14.Z50.31.0004 of the Government of the Russian Federation, 14-15-00186 of the Russian Science Foundation, and the Tomsk State University Academic D. I.  ... 
doi:10.1117/1.jbo.21.7.071114 pmid:27121763 fatcat:qg6wjiirgbdefc7tcoxbyej2na

Mueller coherency matrix method for contrast image in tissue polarimetry

J. L. Arce-Diego, F. Fanjul-Vélez, D. Samperio-García, D. Pereda-Cubián, Peter E. Andersen, Zhongping Chen
2007 Optical Coherence Tomography and Coherence Techniques III  
In this work, we propose the use of the Mueller Coherency matrix of biological tissues in order to increase the information from tissue images and so their contrast.  ...  The application of this analysis to concrete diseases can lead to tissue burn depth estimation or cancer early detection.  ...  ACKNOWLEDGMENTS This work was partially supported by the Spanish Ministry of Education and Science by means of the project TEC2006-06548/TCM.  ... 
doi:10.1117/12.728425 fatcat:drhdi7nk7rbwfbt5yhuy5t5ola

Errors induced by the neglect of polarization in radiance calculations for three-dimensional cloudy atmospheres

Claudia Emde, Bernhard Mayer
2018 Journal of Quantitative Spectroscopy and Radiative Transfer  
At a phase angle of 90 and 400nm wavelength we find the maximum overestimation error of about 8 in clear-sky regions surrounded by clouds due to scattering from clouds into the clear regions.  ...  In backscattering direction the radiance is underestimated by about 5 sun-observer geometries, the error ranges between the two extremes.  ...  The phase angle is 0 • (backscattering direction). Bottom: Stokes vector components Q, U, and V.  ... 
doi:10.1016/j.jqsrt.2018.07.001 fatcat:b3tua4otwbe45je4ytntw2mrfq

Inelastic light-scattering from spin-density excitations in the regime of the persistent spin helix in a GaAs-AlGaAs quantum well

C. Schönhuber, M. P. Walser, G. Salis, C. Reichl, W. Wegscheider, T. Korn, C. Schüller
2014 Physical Review B  
In backscattering geometry, the SDE is formed by spin-flip intrasubband transitions of the spin-split subband.  ...  As expected, the splitting is nonzero if a wave vector is transferred perpendicular to the direction of the spin-orbit field and close to zero for a parallel wave-vector transfer.  ...  (11) and (12) α < 3.5 meVÅ and β > 2.0 meVÅ as the limiting cases from our experiments. From Eq. (5), we can estimate the wave vector k of the PSH, which gives k = (1.14 ± 0.33) × 10 6 m −1 .  ... 
doi:10.1103/physrevb.89.085406 fatcat:zselav37overzo5pd4mzzmmzyy

Turbid medium polarimetry in biomedical imaging and diagnosis

N. Ghosh, A. Banerjee, J. Soni
2011 European Physical Journal : Applied physics  
Studies on polarization properties of scattered light  ...  vector [3, [23] [24] [25] [26] where I, Q, U and V are Stokes vector elements.  ...  The two descriptors are linked in the so-called Stokes-Mueller calculus -given a beam with a Stokes vector S i impinging on an optical element with a Mueller matrix M, the light output from that element  ... 
doi:10.1051/epjap/2011110017 fatcat:i327dvownnccvjlzxb5o5u2h5a

Reflectance and polarization characteristics of various vegetation types [chapter]

Jouni I. Peltoniemi, Maria Gritsevich, Eetu Puttonen
2014 Light Scattering Reviews 9  
An important factor for reducing the amount of data acquired by Earth Observation projects and for collecting more accurate knowledge on the Earth, universe, and environment is to provide a set of reliable  ...  Ongoing research concentrates on getting more quantitative measurements of different forest types, tree species, understory types, biomass, diseases, phases of growth, and crop estimates.  ...  Grant No. 320773 (SAEMPL), the COST Action MP1104 'Polarization as a tool to study the Solar System and beyond', and the Finnish Ministry of Agriculture and Forestry.  ... 
doi:10.1007/978-3-642-37985-7_7 fatcat:d4uxq6pi75epbkqcqjb4plajea

Consistency of rocket and radar electron density observations : implication about the anisotropy of mesospheric turbulence

B. Inhester, J.C. Ulwick, J. Cho, M.C. Kelley, G. Schmidt
1990 Journal of Atmospheric and Terrestrial Physics  
The variation of the anisotropy with height and time shows an anticorrclatioll with the turbulence ievcl of the mesosphere as deduced from the spectral width of the radar echoes.  ...  For a large part of the data from these rocket flights it is found that the radar reflectivity is about IO dB, enhanced over what would be expected from the rocket observations in the case of isotropic  ...  With the help of (lo), the anisotropy parameter c( can be determined independently from (9), provided that again the spcctral index q is known from rocket observations.  ... 
doi:10.1016/0021-9169(90)90021-e fatcat:fn2b465ri5d7fmbv4gwjsrykyy

Polarimetric imaging in backscattering for the structural characterization of strongly scattering birefringent fibrous media

Martin Frenz, Arushi Jain, ANJANI K. MAURYA, Leonie Ulrich, Michael Jaeger, René Rossi, ANTONIA NEELS, PHILIPPE SCHUCHT, ALEX DOMMANN, Hidayet Günhan Akarçay
2020 Optics Express  
To better understand the manifestation of membranes' degree of alignment in polarimetry, we analyzed the spatial variations of the backscattered light's Stokes vectors as a function of the orientation  ...  Interpreting the polarimetric data from fiber-like macromolecules constitutive of tissue can be difficult due to strong scattering.  ...  Disclosures The authors declare no conflicts of interest. Data availability All data is available on request from the corresponding author.  ... 
doi:10.1364/oe.390303 pmid:32549485 fatcat:seqkrpri7zcl3hzfr2now4trsm
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