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Mercury Reflector Spotlight HR50W/S |
The lamp illustrated here employs a standard 50W mercury arc tube sealed into an R64/R20 reflector envelope. The outer bulb has been shaped into a deeper ellipsoidal format than usual, enabling it to optically work more efficiently with the elongated source of the mercury discharge tube.
An aluminised coating inside the bulb provides the light reflective surface. Over the top of this and the front window of the reflector is a layer of finely divided alumina powder, which acts as a light diffusing coating to improve the beam uniformity slightly. It is not a phosphor and provides no colour correction to the light produced by the arc tube. Owing to the reduced thickness of the coating it only has a minimal diffusing effect, and thus a narrow spot beam of light is produced.
Because the arc tube is so small, it is enclosed in a vacuum atmosphere to accelerate run-up. Heat reflectors of platinum paint are applied behind the electrodes, again to conserve heat and shorten the otherwise very long warm-up.
The marking on the lamp is applied to the inside surface, as per the standard method used on lamps for the Japanese market. This ensures that the durability of the marking is unimpaired, it cannot be accidentally wiped off the glass, which frequently occurs on outside-marked lamps.
| Manufacturer: | Iwasaki Electric Co. Ltd. | |
| Lamp Power: | 50 Watts | |
| Lamp Current: | 0.53 Amps | |
| Lamp Voltage: | 90 Volts | |
| Cap: | E26s / 25 | Ni Plated + blue glass |
| Bulb Finish: | Diffuse, Aluminised | Borosilicate |
| Bulb Type: | ER-64 | |
| Overall Length: | 108 mm | |
| Light Centre Length: | N/A | |
| Electrodes: | Backwound thoriated | |
| Atmosphere: | Inner: Ar | Hg | Outer: Vacuum |
| Luminous Flux & Efficacy: | 1150 lm (at 100 hrs) | 23 lm/W (at 100 hrs) |
| Beam Lumens & Efficacy: | 1050 lm (at 100 hrs) | 21 lm/W (at 100 hrs) |
| Colour Temperature & CRI: | CCT: 5700K | CRI: Ra 25 |
| Chromaticity Co-ordinates: | CCx: 0.315 | CCy: 0.380 |
| Burning Position: | Universal | |
| Rated Life: | 6,000 hours (to 70% survival) | |
| Warm Up / Re-strike Time | 5 minutes | 15 minutes max. |
| Factory: | Saitama, Japan | |
| Date of Manufacture: | November 2001 | |
| Original / Present Value: | ||
