NIST has been providing physical measurement standards in photometry and colorimetry for many years. However, the definitions of photometric and colorimetric units and standards are often questioned or found to be insufficient for modern lighting technologies. Large discrepancies between measurements and visual perception are reported in some applications in lighting and signaling, often using light emitting diodes (LEDs). Since photometric units and color scales are established based on vision science, new vision research is required to improve existing standards and metrics.
The goal of NIST's Vision science program is to develop new photometric and colorimetric standards based on vision science to facilitate development of emerging technologies, such as solid-state lighting. We are currently focusing on the development a new metric for the color rendering of light sources (a proposal to replace or supplement Color Rendering Index) and the establishment of an international standard for the effective intensity of flashing lights, both of which are urgently desired by industry.
We work closely with the lighting industry and international standardizing bodies, such as the International Commission on Illumination (CIE), ASTM International, and International Committee of Weights and Measures, and national standardizing bodies including American National Standards Institute (ANSI) and Illuminating Engineering Society of North America (IESNA).
On various measurement issues, we maintain close contacts with other groups and agencies, such as the National Electrical Manufacturers Association (NEMA), the Department of Energy (DOE), the Federal Highway Administration (FHWA), the Federal Aviation Administration (FAA), as well as the Council for Optical Radiation Measurements (CORM).