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Absolute Alignment of the Reference Retroreflectometer at NIST
Published
Author(s)
Carl C. Miller
Abstract
The National Cooperative Highway Research Program (NCHRP Project 05-16) awarded The National Institute of Standards and Technology (NIST) a contract to develop a dedicated reference instrument for measuring retroreflective materials, and a calibration program that provides traceability to the relevant national scales maintained by NIST. The most critical aspect of the NIST Reference Retroreflectometer is the absolute alignment of the three components: thesource, the goniometer, and the detector. Presented are the methods for aligning the components and the uncertainty of the four angles defined as the CIE goniometer system. The expanded uncertainty (k=2) for the observation angle, alpha, is 0,00057 ; for the entrance angle components, beta 1 and beta 2, is 0,0090 ; and for the rotation angle, epsilon, is 0,061 .
Proceedings Title
Commission Internationale de L'eclairage | 25th | | CIE
Volume
152
Conference Dates
June 25-July 2, 2003
Conference Title
Publications Commission Internationale De L'Eclairage CIE
Miller, C.
(2003),
Absolute Alignment of the Reference Retroreflectometer at NIST, Commission Internationale de L'eclairage | 25th | | CIE
(Accessed August 31, 2024)