ultraviolet lamp

A mercury-vapor lamp designed to produce ultraviolet radiation. Also, some fluorescent lamps and mercury-vapor lamps that produce light are used for ultraviolet effects. See also Fluorescent lamp; Mercury-vapor lamp.

Fluorescent and mercury lamps can be filtered so that visible energy is absorbed and emission is primarily in the near-ultraviolet or black-light spectrum (320–400 nanometers). The ultraviolet energy emitted is used to excite fluorescent pigments in paints, dyes, or natural materials.

Mercury-vapor lamps are sometimes designed with pressures that produce maximum radiation in the middle ultraviolet region (280–320 nm), using special glass bulbs that freely transmit this energy. One such lamp type is the sunlamp. Other lamps designed for middle-ultraviolet radiation are known as photochemical lamps. See also Sunlamp.

Some radiation in the 220–280-nm wavelength band has the capacity to destroy certain kinds of bacteria. Mercury lamps designed to produce energy in this region (the 253.7-nm mercury line) are electrically identical with fluorescent lamps; they differ from fluorescent lamps in the absence of a phosphor coating and in the use of glass tubes that transmit far ultraviolet. See also Ultraviolet radiation (biology).

A lamp, especially a mercury-vapor lamp, that produces ultraviolet rays.

The noun has one meaning:

Meaning #1: any source of illumination that emits ultraviolet radiation
  Synonym: ultraviolet source