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Greater calculation capacities and new production technologies have made the production of projection type headlamps with FF reflectors possible for a number of years.
Like DE headlamps, super DE headlamps are a projection system with the same basic operating principle. In this case the reflector surfaces are designed with the aid of FF technology. The strategy is as follows:
  • The reflector reflects as much light as possible from the bulb.
  • The light is reflected so that a maximum passes above the shield to the lens.
  • The light is reflected by the reflector so that light distribution results at the height of the shield, which is then projected onto the road by the lens.

FF technology allows greater spread and better illumination of the sides of the road. Light can be concentrated near the cut off, achieving greater range and allowing more relaxed driving at night. This is particularly notable on long trips. Today, nearly all new projection systems for dipped beams are equipped with FF reflectors. Different size lenses are used with diameters varying from 40mm to 80mm. Larger lenses mean greater light efficiency, but increase the weight.
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Effective reflector area and shape of shield, front view.
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Creation of cut off and slight shading with shield (side view).
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Beam path and light concentration at focal point, top view.
Useable light approx 52%

1. Reflection 2. Light source 3. Shield 4. Lens 5. Cover lens
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Typical dipped beam distribution from Super DE headlamp at cover lens.
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Typical dipped beam distribution from Super DE headlamp as Isolux road diagram.

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