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Monte Carlo techniques for direct lighting calculations

Peter Shirley, Changyaw Wang, Kurt Zimmerman
1996 ACM Transactions on Graphics  
Monte Carlo integration with importance sampling is used to carry out this calculation.  ...  In a distribution ray tracer, the crucial part of the direct lighting calculation is the sampling strategy for shadow r a y testing.  ...  Acknowledgements The authors wish to thank Jim Arvo, Randy Bramley, Andrew Glassner, Holly Rushmeier, Ken Torrance, Bruce Walter and Greg Ward for their help on algorithms and terminology, Ken Chiu for  ... 
doi:10.1145/226150.226151 fatcat:y4vf46rrsrbpjgb6lnnxppdwdi

A Monte Carlo model of light propagation in tissue

S. A. Prahl, Gerhard J. Mueller, David H. Sliney, Roy F. Potter
1989 Dosimetry of Laser Radiation in Medicine and Biology  
The Monte Carlo method is rapidly becoming the model of choice for simulating light transport in tissue. This paper provides all the details necessary for implementation of a Monte Carlo program.  ...  Analytic expressions facilitating convolution calculations for finite flat and Gaussian beams are included. Useful validation benchmarks are presented.  ...  Variance reduction techniques are used to reduce the number of photons necessary to achieve the desired accuracy for a Monte Carlo calculation.  ... 
doi:10.1117/12.2283590 fatcat:s35swpneuvahtcxvmx7xyvgdaa

A stochastic model and a variance-reduction Monte-Carlo method for the calculation of light transport

A. V. Starkov, M. Noormohammadian, U. G. Oppel
1995 Applied physics B  
Combining these approaches and introducing splitting techniques, variance reduction Monte Carlo methods and codes are designed which are adapted to the configuration of the LIDAR.  ...  These codes allow the calculation of multiple scattering effects with high accuracy.  ...  Variations of the physical Monte Carlo techniques often lead to a bias. For the construction of unbiased and variance reduced Monte Carlo simulations weight methods are used.  ... 
doi:10.1007/bf01082268 fatcat:fqjolcr4yra7bcc2at45fvxyzi

Polarized light propagation in multiply scattering media exhibiting both linear birefringence and optical activity: Monte Carlo model and experimental methodology

Michael F. G. Wood, Xinxin Guo, I. Alex Vitkin
2007 Journal of Biomedical Optics  
A Monte Carlo model for polarized light propagation in birefringent, optically active, multiply scattering media is developed in an effort to accurately represent the propagation of polarized light in  ...  The results show close agreement between the experimental measurements and Monte Carlo calculations for phantoms exhibiting turbidity and birefringence, as well as for phantoms exhibiting turbidity, birefringence  ...  Daniel Côté for assistance with extending the polarization-senstive Monte Carlo code, and Mrs. Claire McCann for her assistance with the phantom fabrication.  ... 
doi:10.1117/1.2434980 pmid:17343504 fatcat:b7vtjquwirdg5hx5aeetyiyxcm

Rapid modeling of diffuse reflectance of light in turbid slabs

Lihong V. Wang
1998 Optical Society of America. Journal A: Optics, Image Science, and Vision  
An efficient and accurate hybrid model of the Monte Carlo technique and the diffusion theory was developed to simulate the diffuse reflectance of light in a turbid slab due to an infinitely narrow light  ...  the Monte Carlo computations.  ...  ACKNOWLEDGMENTS This project was sponsored in part by the National Institutes of Health grants R29 CA68562 and R01 CA71980, The Whitaker Foundation, and the Office of Vice President for Research at Texas  ... 
doi:10.1364/josaa.15.000936 pmid:9536515 fatcat:zsemx5wqyrfmdlzbgbq6iszufi

Page 335 of Applied Physics. A and B Vol. B60, Issue 4 [page]

1995 Applied Physics. A and B  
B 60, 335-340 (1995) Appiied PhySics B sna optics © Springer-Verlag 1995 A stochastic model and a variance-reduction Monte-Carlo method for the calculation of light transport A. V. Starkov':*, M.  ...  Combining these approaches and introducing splitting techniques, vari- ance reduction Monte Carlo methods and codes are designed which are adapted to the configuration of the LIDAR.  ... 

A macro-Monte Carlo method for the simulation of diffuse light transport in tissue

Jarod C. Finlay, Timothy C. Zhu, David Kessel
2006 Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XV  
In an effort to reduce the time needed for MC calculations, we have adapted a macro-Monte Carlo (MMC) method (Neuenschwander, et al. 1995, Phys. Med.  ...  The Monte Carlo (MC) method of calculating light distributions in turbid media such as tissue has become the gold standard, especially in complex geometries and heterogeneous tissue.  ...  INTRODUCTION Over the past several decades, Monte Carlo (MC) simulation has come to be accepted as the gold standard for modeling of light transport in turbid media such as tissue.  ... 
doi:10.1117/12.646048 pmid:26113756 pmcid:PMC4477699 fatcat:6qyjv4c5abck3cpnlw4qeidjxq

GPU-Based Monte-Carlo Volume Raycasting

Christof Rezk Salama
2007 15th Pacific Conference on Computer Graphics and Applications (PG'07)  
We demonstrate our technique being capable of producing convincing images, yet flexible enough for digital productions in practice.  ...  We examine the application of stochastic raytracing techniques for volume rendering and provide a fast GPU-based prototype implementation.  ...  Numerous publications exist on Monte-Carlo-based techniques.  ... 
doi:10.1109/pg.2007.27 dblp:conf/pg/Rezk-Salama07 fatcat:arn5we4hnrakbkedsi4jvp2sjy

A new approach for optical assessment of directional anisotropy in turbid media

Pejhman Ghassemi, Lauren T. Moffatt, Jeffrey W. Shupp, Jessica C. Ramella-Roman
2015 Journal of Biophotonics  
A polarized Monte Carlo model and a polarimetric imaging system were devised to predict and measure the impact of birefringence on an impinging linearly polarized light beam.  ...  A study of polarized light transport in scattering media exhibiting directional anisotropy or linear birefringence is presented in this paper.  ...  Vitkin for information about the experiment of Ref. [26] .  ... 
doi:10.1002/jbio.201400124 pmid:25601476 pmcid:PMC4506888 fatcat:di5uda3pmjfahbu36lgohceika

Improved importance sampling for Monte Carlo simulation of time-domain optical coherence tomography

Ivan T. Lima, Anshul Kalra, Sherif S. Sherif
2011 Biomedical Optics Express  
Our method does not produce a systematic bias in the statistical result that is typically observed in existing methods to speed up Monte Carlo simulations of light transport in tissue.  ...  This fast Monte Carlo calculation of the Class I diffusive reflectance can be used as a tool to further study the physical process governing OCT signals, e.g., obtain the statistics of the depth-scan,  ...  The calculation of the apparent position of the collecting fiber accounts for the change in the direction of light propagating through dielectric interfaces due to refraction.  ... 
doi:10.1364/boe.2.001069 pmid:21559120 pmcid:PMC3087565 fatcat:3kmcv4e5jfhhlkbdaf2criwta4

Monte Carlo modeling of optical coherence tomography imaging through turbid media

Qiang Lu, Xiaosong Gan, Min Gu, Qingming Luo
2004 Applied Optics  
In our model the propagating light is represented by a plane wavelet; its line propagation direction and path length in the turbid medium are determined by the Monte Carlo technique, and the process of  ...  We combine a Monte Carlo technique with Mie theory to develop a method for simulating optical coherence tomography ͑OCT͒ imaging through homogeneous turbid media.  ...  Coherent Monte Carlo Techniques A.  ... 
doi:10.1364/ao.43.001628 pmid:15046164 fatcat:yhu5czyqerflnkri2t5iwdytly

Monte Carlo techniques in EXPO

A. Altomare, M. C. Burla, C. Giacovazzo, A. Guagliardi, A. G. G. Moliterni, G. Polidori, R. Rizzi
2000 Acta Crystallographica Section A Foundations of Crystallography  
ECM Nancy s133 conference abstracts s10.m1.o5 Monte Carlo techniques in EXPO.  ...  We will show that a combination of Direct Methods and of Monte Carlo Techniques can routinary and completely solve crystal structures for which a smaller amount of information is available.  ...  In spite of this success, Direct Methods seem not able to definitively solve the phase problem for powder data 3 .  ... 
doi:10.1107/s0108767300023254 fatcat:xargadvtubhoff3xg6s4uo6sxa

Monte Carlo Methods for Simulation of Optical Coherence Tomography of Turbid Media [chapter]

Ivan T. Lima Jr, Sherif S. Sherif
2019 Theory, Application, and Implementation of Monte Carlo Method in Science and Technology  
We describe two importance sampling techniques for a standard Monte Carlo (MC) method that could enable fast simulation of signals from optical coherence tomography (OCT) imaging systems.  ...  Therefore, these importance sampling techniques enable practical simulation of OCT B-scans of turbid media, for example, tissue, using commonly available workstations.  ...  Since it is not practical to simulate light transport in turbid media, for example, tissue, using electromagnetic waves, especially due to diffusive scattering, a Monte Carlo (MC) method of simulating  ... 
doi:10.5772/intechopen.89555 fatcat:e4xwn3r4t5egtc5qzyebkwnbye

Polarization spectral synthesis for Type Ia supernova explosion models

M. Bulla, S. A. Sim, M. Kromer
2015 Monthly notices of the Royal Astronomical Society  
We present a Monte Carlo radiative transfer technique for calculating synthetic spectropolarimetry for multi-dimensional supernova explosion models.  ...  Compared to extracting synthetic observables by direct binning of emergent Monte Carlo quanta, this virtual-packet approach leads to a substantial reduction in the Monte Carlo noise.  ...  AC K N OW L E D G E M E N T S The authors are thankful to the reviewer, Jennifer Hoffman, for her valuable suggestions which helped to improve the quality of the paper.  ... 
doi:10.1093/mnras/stv657 fatcat:u6vte7644vdhhakkwubpiseboy

Fast calculation of multipath diffusive reflectance in optical coherence tomography

Ivan T. Lima, Anshul Kalra, Hugo E. Hernández-Figueroa, Sherif S. Sherif
2012 Biomedical Optics Express  
scattering using Monte Carlo simulations with importance sampling.  ...  This method enables the calculation of these three components of the OCT signal with less than one hundredth of the computational time required by the conventional Monte Carlo method.  ...  We implemented our importance sampling method for Monte Carlo modeling of light transport in multi-layered tissues (MCML) by modifying a C-language software package that is available for download from  ... 
doi:10.1364/boe.3.000692 pmid:22574258 pmcid:PMC3345799 fatcat:ovnhfdxw4zastnc54flkgsbpvm
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