VS - Lighting Systems - Lighting - 998542

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What about lasers in automotive lighting? 17.1. Laser white source benefit from LED experience Whatever the light source, researchers always continue to improve: efficiency, colour stability and reliability. White LEDs have now improved over the last few years and manufacturers are now benefitting from this experience for Laser-based light sources. Management of heat dissipation and phosphor implementation in the LED package are known to be crucial to lifespan and colour stability. Extreme temperatures cause LEDs chip and phosphor efficiencies to drop, leading to a shift in the peak emission wavelength and considerably reducing its life span.

Lasers are able to reach high levels of luminance due to their very concentrated beam. The intrinsic laser characteristics make them good candidates for first application as high- intensity hot-spots and possibly for larger beams in future times. Lasers are monochromatic light sources, so prior to be usable in headlamps a conversion must operate to obtain a white light. Similarly to white LEDs, current developments use a blue laser source that excites a yellow phosphor and emits a very bright white light. Laser-based light sources use laser diode emitting in the near ultraviolet and blue range between 405 nm and 450 nm.

Laser based projector scheme

White light distribution

Laser module

Laser beam remote phosphor

The blue laser light is converted to white light on the phosphor surface

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