HQI-TS Double Ended Compact Metal Halide

The lamp shown was the first light source which, during the mid 1980's, seriously began to make discharge lighting a viable alternative to other light sources in commercial interiors. Previously, the poor colour rendering properties of mercury and sodium lamps had confined them almost completely to industrial lighting. Although good quality white light could be generated by metal halide lamps, it was not possible to make neutral or warm white lamps in low powers with good enough colour consistency for indoor use.

Osram made a breakthrough with this series of lamp, for the first time creating a stable metal halide source in low wattages which made them suitable for accent and display lighting. The key to their success was the reliable method developed for consistently producing a small arc tube with very little variation in dimensions from lamp to lamp, and slowing the rate of sodium loss and therefore colour shift.

The new arc tube shown here is made from a central tube tapered into a conical profile at each end, the reduced diameter sections then being fused to narrow quartz tubes. The seal area is small, and thus the variation from lamp to lamp is also smaller than if the arc tube was made from a single larger piece of quartz. Adoption of the double-ended format realised a design with no metal wires running alongside the arc tube, which in a single ended lamp, become charged and accelerate sodium loss and colour shift. With this development Osram was able to offer a new range of low wattage lamps in warm and neutral white with remarkably uniform performance. A heat-reflective coating of zirconia behind each electrode further improves performance by making arc tube temperature more uniform.
Manufacturer: Osram GmbH
Lamp Power: 150 Watts
Lamp Current: 1.8 Amps
Lamp Voltage: 100 Volts
Cap: RX7s-24
Bulb Finish: Clear quartz
Bulb Type: T-23
Overall Length: 132 mm
Light Centre Length: 66 mm
Electrodes: Thoriated tungsten
Inner / Outer Atmosphere: Ar | Hg (Sn,Tl,In,Na,Li)I+Br Outer: Vacuum
Luminous Flux (100 hrs): 11,000lm @ 100 hours
Luminous Efficacy (100 hrs): 73 lm/W @ 100 hours
Colour Temperature & CRI: CCT: 4000K CRI: Ra 80
Chromaticity Co-ordinates: CCx: CCy:
Burning Position: Horizontal ± 45°
Rated Life: 6,000 hours (to 50% survival and 70% lumens)
Warm Up / Re-strike Time: 4 minutes 10 minutes max.
Factory: Spandau (Berlin), Germany
Date of Manufacture: April 1989
Original / Present Value:
References: 1) Osram Lichtprogramm 2002.