13-11-2012, 03:51 PM
Luxim’s LIFI plasma lamps
Luxim’s LIFI plasma lamps.pdf (Size: 680.4 KB / Downloads: 74)
LOOK MUM, NO WIRES
If you could create the plasma without needing electrodes, then you immediately increase both the operational life and the efficiency of the process. The idea of electrode-less plasma production has been around since demonstrations of the principle by Nikolai Tesla in the late nineteenth century.
A modern, high output electrode-less lamp was developed in the early 1990s by Fusion Lighting in the US. This now-abandoned technology used a cavity magnetron, similar to those found in domestic microwave ovens, to create plasma from powdered sulphur contained in a golf ball-sized quartz glass envelope. While being very energy efficient – 100 lm/W (lumens per Watt) – the sulphur lamp had serious drawbacks. It was only available in very high output versions starting at about 150,000 lumens, which, while great for searchlights, doesn’t have a lot of applications for general commercial, industrial or domestic lighting. The sulphur lamp’s other big problem was that it operated at 2.45GHz – bang in the middle of the wireless spectrum used by everything from cordless phones and AV extenders to WiFi Ethernet – and it took a lot of work to stop all that Radio Frequency (RF) energy from leaking out into the environment .
LIVE LONG & PROSPER
While Luxim is of the opinion that the LIFI’s 10,000 hour life means the lamp will last for the practical lifetime of the fixture, it clearly hasn’t been told of all the 30, 40 and even 50-year-old luminaires still in daily use in production. Lamp replacement for a LIFI system requires changing out the complete ceramic puck, quartz envelope and heatsink package every 10,000 hours, a process no more difficult than changing a conventional lamp. The electronics package, which can also be replaced, has a designed life expectancy of 60,000 hours, which corresponds to nearly six and a half years of continuous operation.
Being on a much smaller scale than the sulphur lamp, the LIFI lamps produce light in quantities that are useful for commercial, street lighting and architectural purposes, including some lower-end projection and entertainment applications. Luxim’s first commercial products a couple of years ago were in the 170W region, but its current offerings are in the vicinity of 266W, with outputs set to increase in future products to an impressive 1kW. All current LIFI lamps are designed to operate from a 28V DC power supply, with future designs moving to the more widely used 24V and 48V DC. The lamp used in the Robin 3 Plasma spot has a light output equivalent to a 400W metal halide lamp – this should make it noticeably brighter the Robin 300E version, which is equipped with a 300W Philips MSD Gold 300/2 lamp.