GB/T 20151-2026 Photometry—The CIE system of physical photometry
GB/T 20151-2026 Photometry—The CIE system of physical photometry
Basic Information
Scope
This document specifies the characteristics of the physical photometry system established by the International Commission on Illumination (CIE) and recognized as the basis for light measurement. It also defines the photometric quantities, units, and standards that make up the CIE physical photometry system and have been officially adopted by the International Committee for Weights and Measures (CIPM), including:
—— Definitions of photometric quantities, symbols, and units;
—— Definitions of the CIE standard spectral luminous efficiency functions for bright vision, dark vision, intermediate vision, and 10° bright vision;
—— Definitions of CIE standard photometric observers that conform to these functions;
—— Definitions of the maximum luminous efficiency for bright vision, dark vision, intermediate vision, and 10° bright vision.
This document is applicable to fields related to photometry calculations, light measurement, and evaluation.