Improved performance photometers have been developed at the National Institute of Standards and Technology (NIST) to utilize the low spectral responsivity uncertainty of spectral irradiance responsivity measurements performed on the facility of Spectral Irradiance and Radiance Responsivity Calibrations using Uniform Sources (SIRCUS). Based on the improved design of the transfer standard photometers, a lower uncertainty detector-based photometric scale is being realized with an uncertainty goal of 0.1 % (k=2). The existing photometer standards that maintain the present NIST illuminance unit can be calibrated against the new transfer standards. In addition, new generation working standard photometers have been developed to utilize the extended group policy to better monitor and correct responsivity changes. The working standards propagate the new reference scales from the transfer standards with a minimal increase in measurement uncertainty. Design issues of the new photometers and the improved scale realization and transfer are discussed.
Proceedings Title: Proceedings 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
Pub Type: Conferences
detector-based calibration, illuminance, photometry, spectral responsivity, standard