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Improved Ultraviolet Measurement Capabilities of NIST's Reference Transmittance Spectrophotometer

Published

Author(s)

Catherine Cooksey, Thomas Larason, Heather Patrick, Clarence Zarobila

Abstract

The National Institute of Standards and Technology (NIST) has maintained and operated custom-built reference instruments to establish the national scale for regular spectral transmittance for more than 50 years. In this paper, we report on improvements to the performance of NIST's current iteration of the reference instrument, the Reference Transmittance Spectrophotometer (RTS), in the ultraviolet (UV) and visible spectral range. The improvements include the installation of a new UV source for increased spectral radiance and a monitor line for reduced signal-to-noise. A new uncertainty budget and validation measurements are presented.
Citation
Applied Optics
Volume
65
Issue
3

Citation

Cooksey, C. , Larason, T. , Patrick, H. and Zarobila, C. (2026), Improved Ultraviolet Measurement Capabilities of NIST's Reference Transmittance Spectrophotometer, Applied Optics, [online], https://doi.org/10.1364/AO.587552, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=936567 (Accessed January 23, 2026)

Issues

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Created January 20, 2026, Updated January 22, 2026
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