Journal ArticleDOI
Determining the optical properties of turbid media by using the adding–doubling method
TLDR
A method is described for finding the optical properties of a slab of turbid material by using total reflection, unscattered transmission, and total transmission measurements and the intrinsic error in the method is < 3% when four quadrature points are used.Abstract:
A method is described for finding the optical properties (scattering, absorption, and scattering anisotropy) of a slab of turbid material by using total reflection, unscattered transmission, and total transmission measurements. This method is applicable to homogeneous turbid slabs with any optical thickness, albedo, or phase function. The slab may have a different index of refraction from its surroundings and may or may not be bounded by glass. The optical properties are obtained by iterating an adding–doubling solution of the radiative transport equation until the calculated values of the reflection and transmission match the measured ones. Exhaustive numerical tests show that the intrinsic error in the method is <3% when four quadrature points are used.read more
Citations
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Journal ArticleDOI
Measurements of the optical properties of tissue in conjunction with photodynamic therapy.
TL;DR: Adistinct increase in the absorption coefficient was seen immediately after treatment, in agreement with the decreasing light intensity observed during the treatment, as measured with the optical dosimeter.
Journal ArticleDOI
Changes in the optical properties (at 632.8 nm) of slowly heated myocardium
John W. Pickering,Saskia Bosman,Paul Posthumus,Peter Blokland,Johan F. Beek,Martin J. C. van Gemert +5 more
TL;DR: The three transport equation optical properties, the absorption coefficient, the scattering coefficient, and the average cosine of the scattering angle, or anisotropy factor have been measured for canine myocardium after it is heated in a water bath at room temperature and at 37-75 degrees C for 1000 s.
Journal ArticleDOI
Optical characterization of melanin
TL;DR: The inverse adding doubling method based on the diffusion approximation and radiative transport theory have been employed to determine the absorption, scattering, and scattering anisotropy coefficients of melanin from the measurements of diffuse transmission, diffuse reflection and collimated transmission using double integrating spheres.
Journal ArticleDOI
Reflectance-based determination of optical properties in highly attenuating tissue.
T. Joshua Pfefer,L. Stephanie Matchette,Carrie L. Bennett,Jessica A. Gall,Joy A. Wilke,Anthony J. Durkin,M. N. Ediger +6 more
TL;DR: This preliminary study toward the development of a diffuse reflectance system with maximum fiber separation distance of less than 2.5 mm appears feasible and moderately accurate, and enhanced accuracy may be achieved through modification of the experimental system and processing algorithms.
Journal ArticleDOI
Changes in tissue optical properties due to radio-frequency ablation of myocardium
TL;DR: The optical properties of pig heart tissue were measured after in vivo ablation therapy had been performed during open-heart surgery to extract the absorption and scattering coefficients and the scattering anisotropy factor g, using an inverse Monte Carlo model.
References
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Journal ArticleDOI
A simplex method for function minimization
John A. Nelder,R. Mead +1 more
TL;DR: A method is described for the minimization of a function of n variables, which depends on the comparison of function values at the (n 41) vertices of a general simplex, followed by the replacement of the vertex with the highest value by another point.
Book
Introduction to Numerical Analysis
Josef Stoer,Roland Bulirsch +1 more
TL;DR: This well written book is enlarged by the following topics: B-splines and their computation, elimination methods for large sparse systems of linear equations, Lanczos algorithm for eigenvalue problems, implicit shift techniques for theLR and QR algorithm, implicit differential equations, differential algebraic systems, new methods for stiff differential equations and preconditioning techniques.
Journal ArticleDOI
A review of the optical properties of biological tissues
TL;DR: The known optical properties (absorption, scattering, total attenuation, effective attenuation and/or anisotropy coefficients) of various biological tissues at a variety of wavelengths are reviewed in this article.
Journal ArticleDOI
New contributions to the optics of intensely light-scattering materials.
TL;DR: In this paper, the Gurevic and Judd formulas were derived from the Kubelka-Munk differential equations, and they are exact under the same conditions as in this paper, that is, when the material is perfectly dull and when the light, is perfectly diffused or if it is parallel and hits the specimen under an angle of 60° from normal.