Philips Mastercolour CDM-R PAR30

In the Autumn of 1994 Philips unveiled a radically new kind of light source, and announced the first successful design of metal halide lamp employing a ceramic discharge tube in place of the usual quartz type.

Ceramics have several advantages over quartz as an arc tube material, most notably that they can better withstand the corrosive nature of the metal halide salts. Thus the arc tube wall temperature can be raised, bringing with it an increase in halide vapour pressures and a consequent gain in luminous efficacy. Colour rendering properties are also improved. Colour stability from lamp-to-lamp is enhanced in this high temperature state, and the greater consistency in shape of the ceramic tubes also minimises colour variations.

The CDM-R lamps are designed along different principles than the rest of the CDM family, a design change being necessary on account of the higher burning temperature of the standard arc tube when assembled into this reflector. Ordinarily this can be compensated for with a change in the mercury dose weight of the arc tube and other minor changes, but for the 70W version the situation is more severe and the arc tube still burns too hot. The 70W CDM-R lamp is unique in that its arc tube is enclosed within a gas filled outer jacket, whereas all other products in the CDM family have vacuum outer jackets. The nitrogen gas filling cools the arc tube significantly by increasing conducted and convected gas losses. No getter is necessary in the outer jackets of these lamps. Furthermore since it is gas filled, this lamp does not suffer the same troublesome end of life failure mechanisms as 70W CDM-TC, with in which arcing in the vacuum outer jacket occurrs.
Manufacturer: Philips Lighting
Lamp Power: 38 Watts
Lamp Current: 0.53 Amps
Lamp Voltage: 88 Volts 3.5 - 5 kV ignition pulse
Cap: E27s/27
Bulb Finish: Stippled hard glass
Bulb Type: PAR-30L (eighths/inch)
Overall Length: 120 mm
Light Centre Length: N/A
Electrodes: Tungsten single coil
Inner/Outer Atmosphere: Ar-Kr85|Dy-Ho-Tm-Tl-Na-Ix Outer: Hard Vacuum
Beam Lumens & Efficacy: 2,200 lm (@ 100 hrs) 57.9 lm/W (@ 100 hrs)
Peak Beam Intensity: 44,000 cd
Colour Temperature & CRI: CCT: 3000K CRI: 81
Chromaticity Co-ordinates: CCx: 0.431 CCy: 0.400
Burning Position: Universal
Rated Life: 9,000 hours to 50% survival
Warm Up / Re-strike Time 3 minutes 15 minutes
Factory: Turnhout Belgium
Date of Manufacture: July 1997
Original / Present Value: