May 14 2009
With the Xenarc D3 and D4 high-pressure gas discharge lamps and matching D3-Xenaelectron control gear OSRAM is the first manufacturer to provide entirely mercury-free HID headlamp systems. As such, the lamps with the "Hg free" label are every bit as effective as mercury-containing solutions in terms of light output and colour temperature. As zinc iodide is used instead of mercury in OSRAM's Xenarc D3 and D4, a separate waste disposal is no longer necessary.
Mercury is a significant part of the filling in conventional xenon lamps. Its purpose is to raise the burning voltage and act as a chemical as well as thermal buffer to prevent oxidation processes and thermally isolate the light arc. By making chemical and geometric modifications to the Xenarc D3 and D4 lamps, Munich lighting manufacturer OSRAM has succeeded in replacing the mercury with non-hazardous zinc iodide. In doing so, the currents inside the lamps had to be increased, for example, and the electrodes and quartz glass reinforced in turn. As a result the Xenarc D3 and D4 achieve a light output and colour temperature comparable to xenon lamps containing mercury.
Efficient maximum performance on the road
The most important attributes of lamps with the "Hg free" label are a luminous flux of up to 3,200 lumens, a service life of 3,000 hours and a daylight-like colour temperature of 4,150 Kelvin. With performance figures like these the new mercury-free Xenarc lamps are far superior to conventional halogen lamps, which are widely used in automotive lighting. Plus, gas discharge lamps such as OSRAM's Xenarc HID lamps are far more efficient than halogen solutions. In contrast to the 18 lumens per watt from halogen lamps, they output around 80 lumens per watt. This reduces CO2 emissions - a 35W Xenarc Lampe produces 1.3 fewer grams of greenhouse gas per kilometre than a 55W halogen lamp. As Xenarc D3 and D4 lamps achieve these ratings without mercury, they are ideal when it comes to reducing both the vehicle's overall CO2 emissions and its environmental impact.
A sustainable system
Another advantage: as the mercury-free gas mixture is safe, OSRAM Xenarc D3 and D4 lamps do not have to be disposed of separately. However, as the mercury-free lamps cannot be combined with conventional HID lamps, each type of lamp has its own base code, mix-ups are avoided. To fit its "Hg free" D3 Xenon lamps OSRAM provides the appropriate, compact Xenaelectron control gear and connecting cables, which all add up to an environmentally friendly system.