Bidirectional Reflectance Distribution Function
Bi-directional Reflectance Distribution Function
The Bi-directional reflectance distribution function (BRDF) describes how
a surface would send light when illuminated from different directions.
The BRDF is one of the crucial parameters needed in radiative transfer
modeling and remote sensing. In recent years, we have made extensive BRDF
measurements on various types of particles from perfect spheres to natural
sediments. Below is a brief summary of the goals of our previous and current
ONR supported BRDF research programs:
Development
of an underwater instrument for in-situ BRDF measurement and take
in-situ
BRDF data
Find an
analytical model to parameterize the in-situ BRDF data to supply
radiative transfer models
Dependence
of the reflectance on the sample thickness
Measurement
of a surface composed of spherical particles (controlled laboratory measurements)
Effect
of pore liquid index of refraction
Effect
of pore liquid absorption coefficient
Polarized
BRDF/transmission measurements and polarization opposition effects in sediment
layers
Ray-tracing
approach to predict sediment BRDF
Equifinality
study on BRDF
Work Completed and Refereed Publications
Developed
a BRDF-meter capable of doing both
in-situ
underwater
and laboratory BRDF measurements
Paper title:
"An instrument to measure the Bi-directional reflectance distribution function
(BRDF) of surfaces"
Journal:
Applied
Optics 39, 6197-6206 (2000)
Abstract
Full
Article
More
Made in-situ
benthic BRDF measurements during CoBOP field experiments and parameterized
data
Paper title:
"Bi-directional reflectance measurements of sediments in the vicinity of
Lee Stocking Island, Bahamas"
Journal:
Limnology
and Oceanography 48, 380-389 (2003)
Abstract
Full
Article
More
Determined
the influential depth of BRDF measurements on sediment particle layers
Paper title:
"Determining the influential depth for surface reflectance of sediment
by BRDF measurements"
Journal:
Optics
Express 11, 2654-2665 (2003)
Abstract
Full
Article
More
Performed
BRDF measurements on prepared particulate surfaces and compared with radiative
transfer models
Paper title:
"Comparisons of BRDF Measurements on prepared particulate surfaces and
radiative transfer models"
Journal:
Applied
Optics 44, 597-610 (2005)
Abstract
Full
Article
More
Additional
work completed with collaborators
Paper title: "Effects
of optically shallow bottoms on upwelling radiances: bidirectional reflectance
distribution function effects"
Journal:
Limnology
and Oceanography 48, 337-345 (2003)
Full
Article
Work in Progress
Extensive
laboratory BRDF measurements on various dry and wet sediment
grain layers
Interstitial
absorbing gel effects on sediment BRDF
Polarization
properties of various sediment particles, especially the "hot-spot" effect
Geometrical
optics algorithms to predict closely packed sediment layer BRDF
Equifinality
of BRDF data
Questions?
Please Contact Dr. Ken Voss
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