High-resolution LED headlamps: Let there be light
The future E-Class with enhanced MULTIBEAM LED headlamps opens up new dimensions in headlamp technology. Each headlamp is now equipped with 84 individually activated high-performance LEDs rather than 24, meaning that they are exceptionally bright and precise, and automatically illuminate the road surface with a previously unsurpassed, precision-controlled distribution of light – without dazzling other road users.
Advances in lighting technology are a tradition at Mercedes-Benz: around 500 LEDs attended to all the lighting functions on a car for the first time on the S-Class in 2013. In 2014 Mercedes-Benz unveiled new MULTIBEAM LED headlamps with precision LED grid modules in the CLS, to make night-time traffic safer for all road users. The statistics show just how important such precision lights are: at night-time, the risk of accidents increases drastically. At night on rural roads there are basically around five times as many accidents with serious consequences as during the day. Although night-time driving on this category of road only accounts for 20 percent of total mileage, this is when and where 40 percent all of all fatal accidents occur (source: BASt, German Federal Office for Roads and Traffic).
Unlike the MULTIBEAM LED headlamps on the CLS, which each feature 24 individual high-performance LEDs, the next generation on the new E-Class uses a newly developed, high-resolution precision LED module as a grid light source, fitted with 84 high-performance LED chips. This is able to react even more dynamically, and the light illuminating the road is high-resolution and even more precise.
Each one of these LEDs can be individually electronically controlled. "Gridding" the light in this way allows the light distribution from the right and left headlamps to be controlled entirely separately and adapted to the traffic conditions with a high level of dynamism. This enables the individual areas of the road surface to be illuminated in a very specific manner.
When it comes to the number of pixels, the same is true of LED headlamps as of a monitor: the higher the number of individually controllable pixels, the higher the resolution and the finer the displayed image. A high number of pixels also allows greater dynamism in the display. In terms of perception, this leads to a clear increase in precision and brilliance.
With 84 LEDs per precision module, the headlamps on the new E-Class allow the resolution of the light pattern to be increased by a factor of around 3.5. As a result, other road users can be protected more precisely against dazzling, and back-glare can be more effectively avoided. This new dimension of precision when it comes to light distribution allows longer use to be made of the partial main-beam lights, increasing safety.
The driver also benefits from improved illumination of the road. Compared with the systems prevalent on the market today, the MULTIBEAM LED headlamps have up to 2.5 times the partial high-beam light output.
The 2nd generation MULTIBEAM headlamps are instantly recognisable.They provide new and surprising visual highlights with passively illuminated, blue light surfaces. These outline the hallmark E-Class "torch effect" daytime running lamps and side lights and, even when low beam or high beam is switched on, create a pleasant blue setting for a fascinating look. This design does not irritate other road users in the slightest thanks to the clever arrangement of the lighting elements. It gives the light design of the E-Class an unmistakable character.
New safety-enhancing functions
As a result of the completely freely configurable high-resolution light distribution, it is possible for the first time to implement all high and low-beam functions of the Intelligent Light System in entirely digital mode and without any mechanical actuators in the new E-Class. As a world first, the dynamic cornering light function is purely electronic. In addition a wealth of new, adaptive light functions are possible which will render night-time driving even safer for both the driver and other road users.
The newly developed adverse weather light function reduces reflections on the oncoming lane when it is raining by specifically dimming individual LEDs and actively helps prevent indirect dazzling of oncoming traffic.
The city light function provides the driver with particularly wide light distribution when driving at low speeds and on lit roads in built-up areas, brightly illuminating difficult-to-see pavements and danger zones.
Data from the navigation system is not only used for the roundabout light function, familiar from the CLS, but can also now be used to detect junctions and motorways and to adapt the light distribution automatically to suit these.
Adaptive Highbeam Assist Plus has also been further optimised: thanks to a larger number of pixels, the dark areas in the light distribution are more precise and dynamic than ever before in partial main-beam mode, and the main beam can be used for longer than before.
A camera on the windscreen supplies the system with the information it needs about the constantly changing traffic situation and is also used by other assistance functions. Four control units per vehicle calculate the ideal light pattern 100 times per second and activate all 84 high-performance LEDs in each precision grid module individually.
The added safety provided by the MULTIBEAM LED technology becomes apparent above all in real traffic situations: in contrast to static high-beam systems, some of which have long ranges, MULTIBEAM LED also supports the driver when there are other vehicles in the field illuminated by the headlamps. Because it masks these out of its light distribution specifically within a fraction of a second, it is possible to drive with main beam switched on at all times. This assures the driver of the best possible light performance at all times, without dazzling other road users.
The LED technology used for the MULTIBEAM headlamps offers further advantages: by way of example, the light from the bright LED headlamps is almost the same colour as daylight and therefore in line with normal human perception patterns. Studies have shown that the closer the colour of artificial light is to daylight, the less the strain on the eyes. With a colour temperature of 5500 kelvin, LED light is closer to daylight (6500 K) than xenon headlamps (4200 K). The 84 high-performance LEDs in the MULTIBEAM LED headlamps also help to increase efficiency thanks to their high lumen output/wattage and are designed to last for the entire vehicle lifetime.
Safety benefits of LEDs in tail lights too: brightness rather than glare
The new E-Class will again feature tail lights with the familiar Mercedes-Benz multi-level functionality - functionality that remains unique in the car industry. The brake lights and indicators are operated with varying light intensity, depending on the driving situation and ambient lighting (day/night).
If the Mercedes driver presses the brake pedal while stopped at traffic lights at night, for instance, the brightness of the brake lights will be automatically dimmed to avoid dazzling anyone behind. It goes without saying that the lights still comply with all statutory requirements.
During the development phase, light experts at Mercedes-Benz carried out experiments at a testing ground, simulating real traffic situations. The tail lights of the test vehicle were operated with varying intensity at different times of the day and under different light conditions, and the brightness and density of the light were measured. With the aid of these values, glare at a specified minimum light intensity was reduced to the desired level.