Osram Power Beam Halogen AR58 - M/84
Osram-GEC of the UK was relatively late to enter the business of low voltage halogen display lighting. For many years its only offering was the 12V 50W type M/32 capsule, for which the company had built an automated production line and enjoyed a favourable cost position. However the range was not expanded to lower power capsules, and GEC never invested in its own production of dichroic reflector halogen lamps - not even for film projection applications.

It was not until the second half of the 1980s that Osram-GEC developed its first low voltage halogen lamp having an integral reflector, with the launch of the Power Beam AR58 family. The range comprised three lamps having beam angles of 8°, 16° and 32°, known as types M/83, M/84 and M/85. The design is based on the Philips AR56 lamps that had been introduced almost a decade earlier. It is not known why GEC increased the diameter by 2mm, which is due to the use of much thicker aluminium than the Philips lamps. The GEC lamps also differ in that each beam angle has its own shape reflector, the length of each lamp varying significantly. The M/83 8° has a shallow specular mirror, this M/84 16° having a deeper facetted pattern, and the M/85 32° having a very deep reflector with peened surface.

In addition to the standard range with toughened clear glass covers, a range of six coloured lamps was introduced around 1989. These employed natural coloured glass covers which produced considerably greater saturation than coloured dichroic reflector lamps available at the time. Shortly after the takeover of Osram-GEC by Osram GmbH of Germany in 1990, the Power Beam lamps were discontinued and the new owner instead promoted its AR70 lamps.
Manufacturer: Osram-GEC Type M/84
Lamp Power: 50 Watts  
Lamp Voltage: 12 Volts  
Lamp Current: 4.17 Amperes  
Cap Type: B15d Ni plated + Vitrite insulator
Bulb Type: AR-58 AR-18 in eighths/inch
Bulb Finish: Clear Glass Aluminium reflector
Filament Type: C-6 Transverse Single Coil
Atmosphere: Bromine, Krypton
Luminous Flux: N/A  
Luminous Efficacy: N/A  
Luminous Intensity: 5,000 cd  
Beam Distribution: 16° to 50% peak
Colour Temperature & CRI: CCT: 3000K CRI: Ra 100
Chromaticity Co-ordinates: CCx: 0.452 CCy: 0.409
Lifetime: 2000 hours to 50% survival
Burning Position: Universal  
Overall Length: 56 mm 2 3/8"
Light Centre Length: N/A  
Factory: Wembley United Kingdom
Date of Manufacture: 1990 March Date Code: XC
Original Value: GB £7.71 (1990)
References: 1) Osram-GEC Specifier Guide : Display Lighting, UK, December 1988, pp.16-18
2) Osram-GEC Specifier Guide : Lamps, UK, October 1989, pp.6-12
3) Osram-GEC Catalogue, UK, 1998, p.63
4) Osram Price List, UK, October 1990, p.3.06