In the past decade, LEDs have become increasingly popular for use on cars, mainly for use as turn signals, brake and park lights, and daytime running lamps, but more recently, also for use in headlights. Now BMW has revealed it is taking the next step in the development of vehicle headlight technology by working on the introduction of laser light headlights. The company says that laser light not only offers energy - and therefore fuel - savings, but could also enable entirely new design possibilities and light functions on vehicles to improve safety. It aims to have the technology ready for series production "within a few years."
While the prospect of cruising down the highway, arming the lasers and blasting obstacles to oblivion might sound appealing to some drivers, BMW says the originally bluish laser light beam isn't emitted directly, but is first converted by means of a fluorescent phosphor material inside the headlight into a pure white light that is suitable for use in road traffic. Therefore, the intensity of the laser light wouldn't pose any risk to humans, animals or wildlife and the emitted light would also be very bright and white, making it more comfortable to the eye.
Because it is a "coherent" light source, meaning its waves have a constant phase difference, BMW says that laser lighting can produce a near-parallel beam with an intensity that is a thousand times greater than LEDs. Additionally, laser lighting boasts less than half the energy consumption of LED headlights, which BMW points out would lead to fuel savings. Whereas LED lighting generates around 100 lumens per watt, laser lighting generates around 170 lumens.
The size of the individual laser diodes, which are just 10 microns in length, are also one hundredth the size of the one-millimeter-long, square-shaped cells used in LED lighting. BMW says this opens up all sorts of new design possibilities for integrating the light source into the vehicle. Although it's theoretically possible to radically reduce the size of the headlights, BMW says it has no plans to do so. Rather, the laser headlights would retain the conventional headlight surface area dimensions, with the reduced depth opening up new possibilities in the positioning of the headlights and the body styling of vehicles.
BMW says the laser lighting technology would be compatible with its current range of lighting technologies, such as Adaptive Headlights, the "Dynamic Lighting Spot" spotlighting system and the "Anti-Dazzle High-Beam Assist." Although it doesn't elaborate, BMW says the laser lighting would also enable the implementation of completely new functions, which will have minimal power consumption.