BMW engineers are currently working on the introduction of laser light in car headlights, with the aim to improve safety as well as efficiency.
Laser lighting is radically different from sunlight, and also from the various types of artificial lighting in common use today.
For a start, laser lighting is monochromatic, which means the light waves all have the same length. It's also a “coherent” light source, which means that its waves have a constant phase difference. As a result, laser lighting can produce a near-parallel beam with intensity a thousand times greater than that of conventional LEDs.
Also, the high efficiency of laser lighting means that laser headlights have less than half the energy consumption of LED headlights, in the end helping to save fuel. Whereas LED lighting generates only around 100 lumens (a photometric unit of light output) per watt, laser lighting generates approximately 170 lumens.
Additionally, laser lighting diodes are very small. With a length of just ten microns (µm), laser diodes are one hundred times smaller than the square-shaped cells used in conventional LED lighting, which have a side length of one millimeter. This opens up all sorts of new possibilities when design cars.
And there’s no risk to humans, animals or wildlife when used in car lighting. This is mostly due to the light not being emitted directly, but initially converted into a form that is suitable for use in road traffic. The resulting light is very bright and white.
The technology is expected to debut in production form on the upcoming 2014 BMW i8, although it has already been previewed on the i8 Concept we saw recently. Note, laser lighting is already used in a variety of consumer products, namely CD and DVD players, however, in most cases it goes unnoticed by the user.