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SPIE 9639-49 Creation and Validation of Spectralon BRDF Targets & Standards



Catherine C. Cooksey, Gael Obein, Georgi T. Georgiev, Christopher Durell, Dan Scharpf, Greg McKee, Michelle L'Heureux


Spectralon is an extremely stable, near-perfect lambertian reflecting diffuser and calibration standard material that has been used by national labs, space, aerospace and commercial sectors for over two decades. New uncertainty targets of 2% on-orbit absolute validation in the Earth Observing Systems community have challenged the industry to improve is characterization and knowledge of almost every aspect of radiometric performance (space and ground). Assuming “near perfect” reflectance and BRDF performance is no longer going to suffice for many program needs. To ensure lowest possible uncertainty, Spectralon has NVLAP accreditation for total hemispherical spectral reflectance measurements. The hemispherical reflectance provides a good mark of general performance, but without the angular characterization critical data is missing from many applications and uncertainty budgets. Therefore, traceable BRDF measurement capability is needed to characterize Spectralon’s “near perfect” angular response and provide a full uncertainty profile to many users. This paper presents an analysis of in-house instrument capability to determine a possible traceable (auditable) BRDF measurement capability for Spectralon materials. The analysis also includes the creation of potential BRDF standards that can be used for traceable inter-comparison or validation articles of BRDF measurements. Our internal capabilities and the new standards are tested against a round-robin cycle of traceable commercial, and national laboratory instruments in an effort to develop an expected error profile for services and products when used in traceable measurements situations.
Proceedings of SPIE


Bi-Directional Reflectance Distribution Function, Spectralon, BRDF, BRF, lambertian, absolute calibration, reflectance target, reflectance standard, ground truth, vicarious calibration


Cooksey, C. , Obein, G. , Georgiev, G. , Durell, C. , Scharpf, D. , McKee, G. and L'Heureux, M. (2015), SPIE 9639-49 Creation and Validation of Spectralon BRDF Targets & Standards, Proceedings of SPIE, [online], (Accessed April 22, 2024)
Created October 12, 2015, Updated November 10, 2018