Sylvania 24V 120W Halogen lamp for operations theatres

halogen lamps for operation theatres are very similar to halogen lamps found for for low voltage projectors lamps.

These lamps feature a low voltage high current filament in a compact quartz envelope. The low voltage high current filament is chosen in order to allow a small area light sources then can easily bundled with a reflector. The Halogen lamps are overdriven similar to projector/display optic lamps to give higher colour temperature reducing their lifespan expectancy.
To ensure maximal optical performance it is necessary for the lamp to be precisely oriented in the luminairs optics, which is the reason these lamps feature rather unusual bases intended to allow simple and precise installing in the fixture. These lamps often resemble the bases found on car headlight may however be scaled up, as with car headlights a similarly precise installation is necessary.

Modern Operations theatre fittings operate at low voltage and have an emergency power supply to allow operation even when there is a power cut. This makes the dual filament construction (one mains voltage and one low voltage battery operated) found on old lamps obsolete.
This lamp is rated at 500hours of life, however similar to traffic signal lamps these lamps are generally not run until the filament breaks but preamptivly changed when the rated life is arrived in order to prevent failure during an operation.