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The NIST Robotic Optical Scatter Instrument (ROSI) and its Application to BRDF Measurements of Diffuse Reflectance Standards for Remote Sensing



Heather J. Patrick, Clarence J. Zarobila, Thomas A. Germer


We describe the robotic optical scatter instrument (ROSI), a new robotic arm-based goniometer for in-plane and out-of-plane reflectance and bidirectional reflectance distribution function (BRDF) measurements of surfaces. The goniometer enables BRDF measurements to be made at nearly any combination of incident and scattering angles, without obstruction from frames or cradles that occur in traditional goniometers made of nested rotation stages. We present exploratory measurements of in-plane and hemispherically-scanned out-of-plane BRDF on a sintered white polytetrafluoroethylene (PTFE) sample using a supercontinuum fiber laser-based tunable light source operated at a wavelength of 550 nm, in order to demonstrate the capabilities of the system. An initial assessment of uncertainties is presented.
Proceedings Title
Earth Observing Systems XVIII
Conference Dates
August 25-29, 2013
Conference Location
San Diego, CA
Conference Title
SPIE Optics and Photonics


BRDF, reflectance, robotics, bidirectional, diffuse, STARR, STARR II, ROSI
Created September 23, 2013, Updated November 10, 2018