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PUBLICATIONS

Optical Characterization of Diffuser-Input Standard Irradiance Meters

Published

Author(s)

George P. Eppeldauer, M Racz, Thomas C. Larason

Abstract

Standard quality irradiance meters have been developed at the National Institute of Standards and Technology (NIST) to realize detector based spectral irradiance scale. The design criteria and the optical and radiometric characterization of diffuser-input irradiance meters are discussed. The input geometry optimization is described for a broad-band InGaAs irradiance meter when measuring a 2856 K incandescent light source. The directional responsivity of the fabricated InGaAs and Si irradiance meters matches the cosine function with a maximum deviation of 0.15% within a 12 degree field-of-view (FOV). Irradiance from sources of different sizes (incident beams with different f/numbers) can be measured over a wavelength range of 350 nm to 1800 nm.
Proceedings Title
Proceedings of Optika '98 5th Congress on Modern Optics, Society of Photo-Optical Instrumentation Engineers (SPIE)
Conference Dates
September 14-17, 1998
Conference Location
Budapest, HU
Conference Title
Congress on Modern Optics
Pub Type
Conferences

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Keywords

aperture, cosine function, detector, diffuser, directional responsivity, irradiance, photodiode, radiometer, spectral responsivity

Citation

Eppeldauer, G. , Racz, M. and Larason, T. (1998), Optical Characterization of Diffuser-Input Standard Irradiance Meters, Proceedings of Optika '98 5th Congress on Modern Optics, Society of Photo-Optical Instrumentation Engineers (SPIE), Budapest, HU, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=841289 (Accessed October 18, 2025)

Issues

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Created September 1, 1998, Updated February 17, 2017
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