For smartphones, computer screens and TVs it’s obvious that the more pixels there are, the better it is. There’s a similar trend for car lights. High resolution
is what’s wanted, with many thousands of pixels. Four technical approaches are currently being developed. It’s not clear which one will come out on top.
Pixel light is an upgrade of matrix light. Each area on the road and its surroundings has virtually its own light source. The more a headlight system has, th
e smaller the illuminated areas on the road can be. In matrix light, which is already in series production, a maximum of a few dozen light sources in the form of individual LEDs are used. Pixel light is expected to provide several thousand light sources – or even tens of thousands. Experts speak of high-resolution headlight systems. Both matrix light and pixel light is ideal
for glare-free high beam. Areas where other road users would be dazzled are simply not illuminated. The rest gets full light.
But how do you get so many pixels from car headlights? One approach comes from cinema and projector technology. It’s called Digital Light Processing (DLP). Many thousands of tiny mirrors are switched electronically and release light onto the screen – or in the case of a car headlight – onto the road. Because of the mirrors the technology is also called Digital Micromirror Device (DMD). The actual light source can be LEDs or laser diodes. Osram is a leading supplier of both. Numerous car and headlight manufacturers are working on DLP technology.
The second method for realizing pixel light relies entirely on semiconductor lasers. It’s based on a micro-electromechanical system (MEMS), in which t
he laser writes the individual pixels as lines on a type of screen in the headlight. You can roughly compare it to an old TV picture tube. The resulting “image” is then projected onto the road. Audi has already announced that its lighting developers are working on this technology.
The two processes described here have one major drawback. They need a lot of space, which means that they create big headlight housings. This is contrary to a trend in the automobile industry which calls for ever smaller headlights. Maybe the third approach will be just right. It’s called Liquid Crystal Display High Definition (LCD-HD) and is completely new. A liquid crystal display lets the light from light emitting diodes through or blocks it. According to engineers at headlight specialist Hella, 30,000 light points, in other words pixels, can be created with this technology. Porsche is involved in the development.
By the time DLP, MEMS or LCD-HD create the first pixels in a production car, at least one or two years will pass. The fourth solution, µAFS, may be quicker. It stands for Micro Advanced Frontlighting System. It’s been more than two years since Osram introduced it together with Daimler and headlight manufacturer Hella. It offers around 3000 pixels per headlight which can all be individually controlled, with each pixel corresponding to one LED from Osram. The first series headlights should be available soon ex works. And that’s why chances that µAFS will prevail in pixel lighting are good.
Ready to go: µAFS is the most advanced technology for pixel light.