The limited-edition R8 LMX will be the first production car in the world to come equipped with laser high beams when it debuts this summer, says its maker Audi. The VW brand has been a leader in automotive lighting, with the R8 being the first production car to boast all-LED headlights. This was followed in 2012 by dynamic turn signals and matrix LED headlights in the updated A8 in 2013.
For the R8 LMX, lasers are used for the high beams to increase lighting range substantially. The laser spot light, which is active at speeds of 60 km/h (37 mph) and above, supplements the LED high beam in the R8 LMX. The production application was developed from technology that will be used for the first time on the new Audi R18 e-tron quattro at the 24 Hours of Le Mans race in June.
With the new laser high beams, one laser module per headlight generates a cone of light with twice the range of the all-LED headlight. Each module comprises four high-power laser diodes. With a diameter of just 300 µm, these generate a blue laser beam with a wavelength of 450 nm. A phosphor converter transforms this into roadworthy white light with a 5500 K color temperature, which is said to be ideal for the human eye, enables drivers to recognize contrast more easily, and helps prevent fatigue. An intelligent camera-based sensor system detects other road users and actively adjusts the light pattern to exclude them.
Dr. Ulrich Hackenburg, Member of the Board of Management for Technical Development, has said that headlamps featuring laser-diode high-beam elements throw a white beam with superior luminosity, optical direction, overall efficiency, and vastly longer life compared to light-emitting diode (LED)-based units now entering the market.
To read more about Audi's pioneering work on laser lights, see http://articles.sae.org/12910/.