VS - Lighting Systems - Lighting - 998542

13. High and low beams optical systems

13.5.1. The reflector: a key component to elliptic headlamps! The reflector is not a basic ellipse. It is designed with several complex elliptical surfaces around the light source and parabolic surfaces on the edges. l The reflection of the rays in the elliptic zones gives the preferred range and coverage (length & max intensity). l The parabolic zones are designed to produce the light in close range (width & near light). 80 m 60 70 40 50 20 30 10 The elliptical reflector is key to beam patterns

The mirror effect of the reflector and its corrosion treatment are paramount to ensure longevity of the projector. If the quality of the reflector is poor, the luminous flux and light projection homogeneity will be seriously affected.

The lens

The lens is an optical device which transmits and refracts light, converging or diverging the beam.

The type of lens surface influences the cut-off projection on the road. The most used types of lenses are modulated and micro-structured ones. The lens material used was historically glass. This was due to temperature issues by using Halogen or Xenon sources close to the lens. The growing popularity of LED light sources is changing this and new generations are now using plastic lenses. They offer design flexibility, weight improvements and more reactive bending mechanisms.

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