Spot Lights & Flood Lights

Stage lighting instruments are used in stage lighting to illuminate theatrical productions, rock concerts and other performances taking place in live performance venues. They are also used to light television studios and sound stages. more...

Terminology is different between the USA and UK for many stagecraft terms. In the USA, lighting fixtures are called "instruments." In the UK, they are called "lanterns" or "luminaires". This article mainly uses terms common to the USA.

Components of Lighting Instruments

See the picture at top right for physical location of most components

Although lighting instruments may look and operate differently, they all have the following components:

Box/Housing/Can/Case

A metal or plastic container to house the whole instrument and prevent light from spilling in unwanted directions. This comprises all of the exterior of the fixture except for the lens or opening. The housing may be designed with specific elements that help reduce heat and increase the efficiency of a lamp. Older instruments were made from rolled and machined steel or aluminum; however, with the advent of the Source Four, many lighting instruments are being made from die-cast metal. Die-casting allows for one single, light-weight piece that is more economical to produce and use. Some instruments are made from plastic, such as the Selecon Pacific.

Lens or opening

The gap in the housing where the light is intended to come out. Many fixtures use a lens to help control the beam of light, though some, such as Parcans and border/cyclorama lights, do not have any lenses, or optics other than the reflector. The lens and the reflector, along with other beam altering devices are part of the optics system.

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