ANSI/IES LM-58-20

Approved Method: Spectroradiometric Measurement Methods for Light Sources

This document describes the requirements and recommendations of the instruments and procedures for spectroradiometric measurements, including those of color performance, spectral irradiance, spectral radiance, and spectral total radiant flux, either in relative or absolute units. The spectral range is from approximately 200 nm to 1,700 nm, where the characterization of light from light sources, visual displays, and light emitting diodes is most commonly done. This document does not provide in-depth detail on every subject but directs the user to references that completely describe the concepts. The light source or device under test shall be operated in accordance with the appropriate IES Light Measurement (LM) or American National Standards Institute (ANSI) document pertaining to the device; such operation is not described in this document.