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Measuring the Luminance of a Retroreflective Sign



Carl C. Miller, T Heimer, Tim Donahue, M Schwartz, David Kuniega


The area of retroreflective signage for traffic control is moving from fixed retroreflective requirements to a traffic scenario/performance based system. CIE Technical Report 54.2, Retroreflection: Definition and Measurement , published in 2001, offers several methods for measuring the coefficient of retroreflected luminance. In this experiment, two CIE 54.2 methods, The Ratio Method and The Direct Luminance Method, along with a new method, Total Luminous Flux Method, are compared in the laboratory and through uncertainty analysis. The results show the Total Luminous Flux method has the potential for the lowest measurement uncertainty and implementation of the Direct Luminance method is not trivial showing errors as large as 20 % are easily possible.
Proceedings Title
Conference Proceeding of the International Commission on Illumination | 26th | 2007 | CIE |
Conference Dates
July 4-11, 2007
Conference Location
Beijing, CH
Conference Title
CIE International Commission on Illumination


luminance, retroreflection, uncertainty


Miller, C. , Heimer, T. , Donahue, T. , Schwartz, M. and Kuniega, D. (2007), Measuring the Luminance of a Retroreflective Sign, Conference Proceeding of the International Commission on Illumination | 26th | 2007 | CIE |, Beijing, CH (Accessed July 24, 2024)


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Created July 11, 2007, Updated June 14, 2017