Lamps are light sources that emit incoherent light for illumination.

Spectral lamps radiate line spectra of various gases and metal vapors with high brightness and spectral purity

Lighting fixtures and lamp sockets produce artificial light in industrial areas or workspaces, and mechanically hold and electrically connect lamp bulbs to wiring

High intensity discharge lamps (HID) contain compact arc tubes, which enclose various gases and metal salts, operating at relatively high pressures and temperatures.

Fluorescent lamps are high-efficiency lamps that use electrical discharge through low-pressure mercury vapor to produce ultraviolet (UV) energy, which is then transformed into visible light

Incandescent lamps generate light by passing an electric current through a thin filament wire (usually of tungsten) until the wire is extremely hot

Time and frequency standards can include cesium or rubidium atomic clocks, quartz oscillators, hydrogen masers and other master clocks.