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Title: Laser light scattering in turbid media: Part I: Experimental and simulated results for the spatial intensity distribution.

Abstract

Abstract not provided.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1148163
Report Number(s):
SAND2007-2900J
523268
DOE Contract Number:
DE-AC04-94AL85000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Optics Express; Related Information: Proposed for publication in Optics Express.
Country of Publication:
United States
Language:
English

Citation Formats

Linne, Mark, Berrocal, Edouard, Sedarsky, David, Paciaroni, Megan, and Meglinski, Igor. Laser light scattering in turbid media: Part I: Experimental and simulated results for the spatial intensity distribution.. United States: N. p., 2007. Web.
Linne, Mark, Berrocal, Edouard, Sedarsky, David, Paciaroni, Megan, & Meglinski, Igor. Laser light scattering in turbid media: Part I: Experimental and simulated results for the spatial intensity distribution.. United States.
Linne, Mark, Berrocal, Edouard, Sedarsky, David, Paciaroni, Megan, and Meglinski, Igor. Tue . "Laser light scattering in turbid media: Part I: Experimental and simulated results for the spatial intensity distribution.". United States. doi:.
@article{osti_1148163,
title = {Laser light scattering in turbid media: Part I: Experimental and simulated results for the spatial intensity distribution.},
author = {Linne, Mark and Berrocal, Edouard and Sedarsky, David and Paciaroni, Megan and Meglinski, Igor},
abstractNote = {Abstract not provided.},
doi = {},
journal = {Optics Express},
number = ,
volume = ,
place = {United States},
year = {Tue May 01 00:00:00 EDT 2007},
month = {Tue May 01 00:00:00 EDT 2007}
}
  • The spatial distribution of laser radiation intensity in turbid condensed media is studied analytically, numerically, and experimentally by the optoacoustic method. Based on optoacoustic measurements and Monte Carlo numerical simulations, the relation is obtained between the optical characteristics of a scattering medium and the position of the maximum of the spatial distribution of radiation intensity in the medium. It is shown that, when the anisotropy factor exceeds 0.8, this dependence has a universal type in the ranges of absorption and scattering coefficients typical for biological tissues. The method is proposed for measuring the extinction and absorption coefficients in light scatteringmore » media from the temporal shape of an optoacoustic pulse detected in relative units. An approximate method for solving a radiation transfer equation is verified, and the regions of application of the P{sub 3} and P{sub 5} approximation are established.« less
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  • Continuous-wave ultrasonic modulation of scattered laser light has been used to image objects in tissue-simulating turbid media for what is to our knowledge the first time. The ultrasound wave focused into the turbid media modulates the laser light passing through the ultrasonic focal zone. The modulated laser light collected by a photomultiplier tube reflects the local mechanical and optical properties in the focal zone. Buried objects are located with millimeter resolution by scanning and detecting alterations of the modulated optical signal. This technique has the potential to provide a noninvasive, nonionizing, inexpensive diagnostic tool for diseases such as breast cancer.
  • Many methods of optical tissue diagnosis require that measurements be performed with small source{endash}detector separations in a backscatter geometry. Monte Carlo simulations are used to demonstrate that for these situations light transport depends on the exact form of the angular scattering probability distribution, {ital P}({theta}). Simulations performed with different forms of {ital P}({theta}) with the same value of {l_angle}cos{theta}{r_angle} result in the collection of significantly different fractions of the incident photons, particularly when small-numerical-aperture delivery and collection fibers are employed. More photons are collected for the distribution that has a higher probability of scattering events with {theta}{approx_gt}125{degree}. For the clinicallymore » relevant optical parameters employed here, the differences in light collection are {approx_gt}60{percent}. {copyright} {ital 1996 Optical Society of America.}« less