ultraviolet (UV) lamp, a lamp that emits electromagnetic radiation in a range between 4 and 400 nm, or beyond the violet spectrum of visible light. Equipped with a nickel oxide filter, an ultraviolet lamp radiating at wavelengths around 360 nm can be used to examine hairs infected with certain agents. The pathogens reflect the ultraviolet light with a greenish-yellow fluorescence. See also Wood’s light.
