The first tungsten-halogen lamps were developed in 1956 by Zubler and Moseby of General Electric.
Tungsten-halogen lamps were first used in theatrical applications in 1960.
Tungsten-halogen lamps have solved a number of problems which were inherent in conventional incandescent lamps. The bulbs of incandescent lamps tended to blacken as the
lamp
aged due to tungsten particles adhering to the glass envelope . The filaments were large. The
color temperature
of incandescent lamps was low (2,700°K). The filaments were large, and consequently not very efficient optically. This caused the light to be yellowish, which is very different from the hue of natural light, and is perceived by the eye as being less bright than blue. The
color temperature
also tended to decrease as the
lamp
got older, resulting in inconsistencies between different luminaires.
The tungsten-halogen
lamp
maintains its initial light output and high
color temperature
(3,200°K) throughout
lamp
life. The small size of the lamps and filaments make the
light source
closer to a point source, enhancing the optics of the luminaires.
Although the halogen cycle can be used to extend
lamp life
considerably, manufacturers preferred to exploit the advantages of the
tungsten-halogen cycle
to produce a more compact
light source
whose filament burns at a higher temperature.
Tungsten-halogen lamps were originally called Iodine-Quartz lamps: iodine referring to the gas element, and quartz referring to the quartz glass envelope. Iodine is a member of the halogen element family, which also includes bromine, chlorine, fluorine and astatine. Since the invention of these lamps, bromine has for the most part replaced iodine. As a result, the name of these lamps has been changed: tungsten standing for the filament and halogen standing for the gas element.
Today the tungsten-halogen
lamp
has become standard in the theatre, in television studios, and in the film industry.
HPL High Performance
Halogen
Lamps
HPL lamps are an innovative breakthrough in compact tungsten halogen
lamp
technology, designed and engineered for brilliant efficiency and extraordinary output. Four compact tungsten coil segments, arranged in a symmetric pattern, enable maximum light collection efficiency with far less energy consumption than conventional tungsten halogen lamps. The unique filament design, coupled with a special
heat sink
base, ensures high lumen output with lower heat
load
to the socket.
