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Application of polarization for optical motion-registered SPECT functional imaging of tumors in mice

Justin S. Baba, Shaun S. Gleason, James S. Goddard, Michael J. Paulus, Alexander V. Priezzhev, Gerard L. Cote
2005 Optical Diagnostics and Sensing V  
This paper focuses on the utilization of polarization filtering to minimize specular reflection from a glass tube used for holding live human-tumor-mice during functional imaging in a dedicated small animal  ...  The use of small animal models to investigate human diseases is an integral part of the development of new diagnostic and treatment regimens.  ...  of the elimination of input source specular reflections off of the walls of the glass tube mouse holder by application of polarization filtering.  ... 
doi:10.1117/12.597442 fatcat:uja5ssxk4rhrbnm6dg6xzobep4

Circular Polarizers Enhance Visibility of Endothelium in Specular Reflection Biomicroscopy

E. Peli
1985 Archives of Ophthalmology  
of specular reflection biomicroscopy of corneal endothelium. using circular polarizer to eliminate glare from epithelium.  ...  The dif fusely reflected light is unpolarized and less suppressed by the circular polarizer, rendering it even more visible.  ... 
doi:10.1001/archopht.1985.01050050062018 pmid:3994575 fatcat:kkc5snrfgbf7hp3z76gcf4eph4

Models of Polarized Light from Oceans and Atmospheres of Earth-like Extrasolar Planets [article]

P. R. McCullough
2006 arXiv   pre-print
Specularly reflected light, or glint, from an ocean surface may provide a useful observational tool for studying extrasolar terrestrial planets.  ...  We predict the spatially-integrated reflected light and its degree of polarization as functions of the diurnal cycle and orbital phase of Earth and Earth-like planets of various imagined types.  ...  Ruth DeFries and Dr. John Townshend (University of Maryland at College Park, Department of Geography), with revisions made by Dr. James Collatz (Code 923, NASA Goddard Space Flight Center).  ... 
arXiv:astro-ph/0610518v1 fatcat:kz4jl6peqbgahbfmyhoslr56da

Circularly polarized spherical illumination reflectometry

Abhijeet Ghosh, Tongbo Chen, Pieter Peers, Cyrus A. Wilson, Paul Debevec
2010 ACM SIGGRAPH Asia 2010 papers on - SIGGRAPH ASIA '10  
, and specular roughness of isotropic BRDFs.  ...  The method is based on a novel analysis of the Stokes reflectance field of circularly polarized spherical illumination and yields per-pixel estimates of diffuse albedo, specular albedo, index of refraction  ...  The content of the information does not necessarily reflect the position or the policy of the US Government, and no official endorsement should be inferred.  ... 
doi:10.1145/1866158.1866163 fatcat:22oonipklra35gavlavixdgxku

Circularly polarized spherical illumination reflectometry

Abhijeet Ghosh, Tongbo Chen, Pieter Peers, Cyrus A. Wilson, Paul Debevec
2010 ACM SIGGRAPH Asia 2010 papers on - SIGGRAPH ASIA '10  
, and specular roughness of isotropic BRDFs.  ...  The method is based on a novel analysis of the Stokes reflectance field of circularly polarized spherical illumination and yields per-pixel estimates of diffuse albedo, specular albedo, index of refraction  ...  The content of the information does not necessarily reflect the position or the policy of the US Government, and no official endorsement should be inferred.  ... 
doi:10.1145/1882262.1866163 fatcat:dlwffy33fvfblbnndklv3sq2yq

Circularly polarized spherical illumination reflectometry

Abhijeet Ghosh, Tongbo Chen, Pieter Peers, Cyrus A. Wilson, Paul Debevec
2010 ACM Transactions on Graphics  
, and specular roughness of isotropic BRDFs.  ...  The method is based on a novel analysis of the Stokes reflectance field of circularly polarized spherical illumination and yields per-pixel estimates of diffuse albedo, specular albedo, index of refraction  ...  The content of the information does not necessarily reflect the position or the policy of the US Government, and no official endorsement should be inferred.  ... 
doi:10.1145/1882261.1866163 fatcat:xhro4c2r7zcebhodlfxspxtnam

Incorporation of polarization into the DIRSIG synthetic image generation model

Jason P. Meyers, John R. Schott, Scott D. Brown, Sylvia S. Shen
2002 Imaging Spectrometry VIII  
The bi-directional reflectance distribution function (BRDF) module was rewritten and modularized to accommodate a variety of polarized and unpolarized BRDF models.  ...  This paper presents the methods used to add modeling of polarization phenomenology.  ...  Sparrow BRDF model Torrance and Sparrow developed a simple unpolarized BRDF model for predicting the off-specular reflections from roughened surfaces. 7 The model used a microfacet surface model and  ... 
doi:10.1117/12.451545 fatcat:jen52wcrpzfsbkgohb32dehuam

Scattering and polarization properties of the scarab beetle Cyphochilus insulanus cuticle

Christina Åkerlind, Hans Arwin, Tomas Hallberg, Jan Landin, Johan Gustafsson, Hans Kariis, Kenneth Järrendahl
2015 Applied Optics  
From the MMSE measurement it is found that the beetles appear as dielectric reflectors reflecting linearly polarized light at oblique incidence with low gloss and low degree of polarization.  ...  Here, reflectance, scattering and polarization properties of the cuticle of the scarab beetle Cyphochilus insulanus are studied with Spectral Directional Hemispherical Reflectance (SDHR), Bidirectional  ...  When using normalized Muller-matrix elements the degree of polarization of reflected light for incoming unpolarized, s-and p-polarized light are denoted , , and respectively, and are defined as = A polarization  ... 
doi:10.1364/ao.54.006037 pmid:26193149 fatcat:lv7fvqol6ndhnhot5mt2brpiuq

Photoreceptor twist: a solution to the false-color problem

R. Wehner, G. D. Bernard
1993 Proceedings of the National Academy of Sciences of the United States of America  
Light reflected from waxy plant surfaces is partially linearly polarized.  ...  spectral but also by the polarization properties of the reflecting surface.  ...  Measurement of the State of Polarization of Light Reflected from Plant Surfaces.  ... 
doi:10.1073/pnas.90.9.4132 pmid:11607379 pmcid:PMC46460 fatcat:fhluqwgjsjbozl6clqchnkrxue

Physically based reflectance model utilizing polarization measurement

Takayuki Nakano, Yasuhisa Tamagawa
2005 Applied Optics  
A surface bidirectional reflectance distribution function (BRDF) depends on both the optical properties of the material and the microstructure of the surface and appears as combination of these factors  ...  Our BRDF model treats the surface as an aggregation of microfacets, and the diffractive effect is negligible because of randomness. An example model of a painted aluminum plate is presented.  ...  specular reflection on surfaces.  ... 
doi:10.1364/ao.44.002957 pmid:15929283 fatcat:mrvuxqed2rfmtnzdognu2yaadq

Multiview face capture using polarized spherical gradient illumination

Abhijeet Ghosh, Graham Fyffe, Borom Tunwattanapong, Jay Busch, Xueming Yu, Paul Debevec
2011 ACM Transactions on Graphics  
The patterns -one following lines of latitude and one following lines of longitude -allow the use of fixed linear polarizers in front of the cameras, enabling more efficient acquisition of diffuse and  ...  Key to our method is a new pair of linearly polarized lighting patterns which enables multiview diffuse-specular separation under a given spherical illumination condition from just two photographs.  ...  The content of the information does not necessarily reflect the position or the policy of the US Government, and no official endorsement should be inferred.  ... 
doi:10.1145/2070781.2024163 fatcat:j65xdt3vbrfkznsel47qr6bp3m

Multiview face capture using polarized spherical gradient illumination

Abhijeet Ghosh, Graham Fyffe, Borom Tunwattanapong, Jay Busch, Xueming Yu, Paul Debevec
2011 Proceedings of the 2011 SIGGRAPH Asia Conference on - SA '11  
The patterns -one following lines of latitude and one following lines of longitude -allow the use of fixed linear polarizers in front of the cameras, enabling more efficient acquisition of diffuse and  ...  Key to our method is a new pair of linearly polarized lighting patterns which enables multiview diffuse-specular separation under a given spherical illumination condition from just two photographs.  ...  The content of the information does not necessarily reflect the position or the policy of the US Government, and no official endorsement should be inferred.  ... 
doi:10.1145/2070752.2024163 fatcat:yc5tr6ypvzh75h5wway5bn25c4

Multiview face capture using polarized spherical gradient illumination

Abhijeet Ghosh, Graham Fyffe, Borom Tunwattanapong, Jay Busch, Xueming Yu, Paul Debevec
2011 Proceedings of the 2011 SIGGRAPH Asia Conference on - SA '11  
The patterns -one following lines of latitude and one following lines of longitude -allow the use of fixed linear polarizers in front of the cameras, enabling more efficient acquisition of diffuse and  ...  Key to our method is a new pair of linearly polarized lighting patterns which enables multiview diffuse-specular separation under a given spherical illumination condition from just two photographs.  ...  The content of the information does not necessarily reflect the position or the policy of the US Government, and no official endorsement should be inferred.  ... 
doi:10.1145/2024156.2024163 fatcat:2ikaai3evned3aetjrcrtuo6hq

Polarization of light on reflection by some natural surfaces

Hsi-Shu Chen, C R Nagaraja Rao
1968 Journal of Physics D: Applied Physics  
The polarization features of light reflected by soil, desert sand, white sand and water under different conditions of illumination with natural (unpolarized) and linearly polarized light have been investigated  ...  The polarization of light reflected by soil, desert sand and white sand exhibits pronounced wavelength dependence. There is over-all similarity in the behaviour of soil and desert sand.  ...  Sekera of the Department of Meteorology, University of California, Los Angeles, for his interest and encouragement while the work was in progress.  ... 
doi:10.1088/0022-3727/1/9/312 fatcat:si5ft7smpffw5lz6vcymwewhqu

Estimation of Multiple Illuminants Based on Specular Highlight Detection [chapter]

Yoshie Imai, Yu Kato, Hideki Kadoi, Takahiko Horiuchi, Shoji Tominaga
2011 Lecture Notes in Computer Science  
We note that specular highlights on inhomogeneous dielectric object surfaces includes much information about scene illumination according to the dichromatic reflection model.  ...  First, we describe several methods for detecting specular highlight areas. We assume a curved object surface illuminated by multiple light sources from different directions.  ...  Detection Using a Polarization Filter The polarization property of light reflected from an object surface is available for highlight detection.  ... 
doi:10.1007/978-3-642-20404-3_7 fatcat:xrhxxgr4r5dhxftpdhpcbmfhja
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