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)
- 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)
- 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)
- 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)
- 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