Lighting technologies

From the incandescent lamp to the digital high-tech application: light-years of progress with Audi

Halogen incandescent lamps enabled initial technical improvements that also affected the look of automobiles. With free-form headlights in the nineteen-eighties and clear lens covers in the late nineteen-nineties, designers were increasingly able to use light as a styling element to define the face of Audi models. The second-generation xenon headlights in the 1994 Audi A8 and the tiltable modules from 2003 onward marked development leaps that elevated the quality of light and the customer’s experience to a new level. The technology of LED light introduced in 2008 was used by Audi to make a veritable quantum leap. It replaced the previously unsegmented and indivisible lighting units, significantly surpassing the efficiency, range and illumination performance of the previous headlights. In addition to this technical progress, light-emitting diodes permitted much higher degrees of freedom in designing the light source, so light as a styling element acquired much greater significance. Segmentation as a Matrix and digitization expanded the potential even further: The lights of an Audi no longer serve the mere purpose of providing illumination. They create a new customer experience by pioneering external communication including social interaction as well as enabling a wide variety of lighting design choices.

Headlight technology: looking ahead

In 2004, Audi used light-emitting diodes for the first time in LED headlights, in the daytime running light of the Audi A8.Light-emitting diodes are semiconductors that can directly convert electrical energy into light. They operate with particularly high efficiency: their energy consumption is low and their light output high. In 2008, the first full LED headlights followed in the Audi R8. Today, headlights with LED technology are standard equipment in all model ranges – except for the Audi A1 as an entry-level model. In 2013, Audi was the first automobile manufacturer to be awarded the eco-innovation certificate of the European Union for using LED technology.

Light-emitting diodes still provide the foundation for headlight technology today. Whereas the high-beam assist system, by detecting oncoming traffic, automatically switches the high beam on or off, Matrix LED headlights paved the way for new applications in the Audi A8 in 2013. The high-beam light’s 25 individual light-emitting diodes could be discretely activated or deactivated and, alternatively, even be dimmed. Back then as today, the lighting system by means of a camera detects other road users with high precision, avoids headlight dazzle by deactivating individual diodes while still brightly illuminating the road. Navigation-based, it responds to the respective driving situation and predictively distributes the light according to the route data. In the case of the smart cornering light, the focal point of the light shifts in the direction of the corner as soon as the driver turns the wheel.

The laser as an additional high-beam light, which debuted in the Audi R8 LMX limited edition in 2014, doubled the headlight range. In 2017, the A8 combined the latest ideas: Rear lights with OLED technology and HD Matrix LED headlights featuring the Audi laser as an addition high-beam light represented the benchmark among the competition. This is achieved by each headlight integrating two times 16 small, discretely controllable light-emitting diodes to generate a multi-row Matrix LED high beam. The system delivers cornering, urban and freeway lighting with maximum precision and complements the high-beam light by masking out other road users with enhanced accuracy. The laser is activated at a minimum speed of 70 km/h (43.5 mph) and as a spotlight illuminates a distance of roughly 600 meters (1,970 ft).

In the Audi e-tron, the brand’s first fully electric model, the digital Matrix LED headlight with a digital micromirror device (DMD) debuted in 2019. It marked another Audi success in launching a world innovation in the area of low-beam and high-beam lighting in large-scale production, because it was the first to feature the installation of DMD technology that had its origins in video projectors in an automobile. At its core is a small chip that integrates 1.3 million micromirrors, each with an edge length of just a few hundredths of a millimeter. Using electrostatic fields, every single one of them can be tilted at a rate of up to 5,000 times per second. Depending on the position, the light from three high-performance LEDs reaches the DMD chip in concentrated form via specifically calculated lenses and a free-form reflector. From there, the light hits the road either via lenses or an absorber that masks it out. This goes hand in hand with as many as three innovations delivering high customer value. Above and beyond the previously known, albeit more precisely achievable functions, the technology is able to project a kind of “light carpet” in front of the vehicle when traveling on expressways such as the autobahns in Germany.This so-called lane light brightly illuminates the vehicle’s own lane, dynamically spreads when changing lanes, and thus enhances traffic safety. Innovation number two: The orientation light facilitates lane-keeping especially in narrow sections by indicating the vehicle’s position in its own lane as a strip-like boundary. Innovation number three: Used in combination with the optional Night Vision Assist feature is the marking light. It detects pedestrians close to the roadway and alerts the driver to them by means of a precision light cone.

Rear light technology: A signaling function evolves into a display

Similar to the headlights, the rear lights have seen a rapid evolution at Audi as well. In 2011, LEDs provided the rear lights of the Audi A6 with a new visual homogeneity and enhanced the efficiency of lighting technology, which also benefits other road users: The LED brake light responds instantaneously and thus two tenths of a second faster than an incandescent lamp. As a result, the driver of a following vehicle can react faster. Accordingly, at 100 km/h (62 mph), the distance on which a following vehicle is able to brake is extended by nearly 6 meters (20 ft). In 2012, the turn signal with dynamic indication was introduced in the Audi R8. This pioneering achievement, in which Audi worked closely together with approval authorities, has since become standard equipment. Due to the movements of the turn signal, directional changes are more clearly perceptible by the drivers of following vehicles, especially from a distance and at night.

OLED rear lights on the Audi TT RS rang in a new era in 2016. The light of the light-emitting diodes, which consist of organic material, is extremely homogeneous and precise. OLED light sources are ultra-thin area light sources and do not require reflectors. This technology is efficient, lightweight and visually impressive. In 2020, Audi was the first manufacturer to digitize the rear lights that turns them into a display and opens up new potential in terms of styling, personalization and safety. Due to the increased segmentation of the digital OLEDs to currently 18 segments, diverse rear light designs can be achieved for the first time. Customers purchasing a Q5 can choose between three rear light signatures. Irrespective of these choices, a particularly sporty signature can be set in “dynamic” mode in Audi drive select. In addition, the proximity indication feature enhances traffic safety: When the Q5 is standing still and another road user approaches from behind at a distance of less than two meters (6.5 ft), all OLED segments are activated. As a result, the visible area is enlarged and perceptibility enhanced. A total of five different visual lighting patterns can be achieved here with just a single set of hardware.

An experience for the senses: Design, signature and dynamics

On or off: Those were the lighting options for the parking light, low and high beam in the analogue age. Functions above and beyond purely seeing and to be seen hardly existed. Styling potential was rather limited up until the nineteen-eighties. Smaller light sources paved the way for increasingly individual and distinctive designs. Halogen incandescent lamps enabled free-form headlights. The clear cover lenses appearing in the late nineteen-nineties and the small xenon lamps gave Audi’s headlights a look resembling the pupil of a human eye. They permitted more compact headlight shapes and component arrangements. This marked the advent of a new business segment of offering options in the area of lighting and a resulting opportunity for differentiation underscoring the brand’s premium character in line with technical progress.

Segmentation and modularization allow for styling freedoms in vehicle design and foster new creativity in the design and animation of light. In combination with digitization, new functionalities emerged such as lighting signatures and dynamic lighting scenarios. As is typical for Audi, all lighting signatures are designed for absolute precision and homogeneity. They emphasize the width of the vehicle by means of distinctive horizontal lines and accentuating details on the car’s exterior. In their interaction, these segments form a body, ensuring that the vehicle sports a visually wider look and sits squarely on the road.

Styling innovations and customer experience always go hand in hand with maximum functionality and high customer value. In 2004, LED daytime running lights defined Audi’s face for the first time while enhancing visibility. Today, on the A3 as the first model range, Matrix LED headlights can feature model- and line-specific signatures in the daytime running lights using just one set of hardware.

The dynamic lighting scenario of the leaving and coming home function in the Audi A7 Sportback and A8 created a new customer experience. This function is activated when unlocking and leaving the car. The digital Matrix LED headlights with DMD technology for the Audi e-tron are now offering five different welcoming versions within the range of extended dynamic lighting scenarios. They can appear as projections on a wall or on the ground. With such diversity and innovative prowess, Audi has been and will remain not just the globally leading brand in automotive lighting technology, but also makes this type of “Vorsprung durch Technik” visible in the design of lighting signatures and their dynamic enactment.

Versatile and forward-thinking: Safety, communication and interaction

Light at Audi stands for a symbiosis of technology, design, safety and customer experience. Connectivity ensures smart functionality. Lamps turn into displays and a one-dimensional signaling and warning function of the past will evolve into a versatile means of communication with the external world, going forward.

Be it at the front or rear, thanks to freely selectable signatures with identical hardware, a wealth of variety has found its way into the brand’s model ranges. Going forward, it is conceivable that, via the MMI, owners will be able to switch between a wide range of signatures or achieve custom designs. Via the myAudi app, Audi e-tron customers already have the opportunity of booking additional lighting functions even after having purchased their car – anytime and with great flexibility. Other models will follow.

Today, the digital Matrix LED headlight with DMD technology already offers projections for specific lane guidance and orientation, which serve to make driving easier and avoid accidents.As a forward-thinking prospect, this technology, combined with other ideas, may enhance the driver’s attention as well as mutual consideration and respect among road users.

Since 2020, the proximity indication feature in the Audi Q5 has made car-to-x communication of the rear lights a reality as well. Hence Audi is pursuing an anthropocentric path and, with the digital OLED rear lights, paving the way into a new age. The rear lights are evolving into a display medium, which can be extended by versatile functions in the next evolution. In the medium run, the digital OLED will have more than 60 segments, each of which can be individually controlled and systematically activated. Looking forward, besides enabling the versatile styling and personalization of lighting designs, the digital OLED, for instance, will be able to issue early warnings of local hazards such as slippery roads and the end of traffic jams to other road users.

Looking forward even further, Audi is working on the flexible digital OLED. Instead of the roughly 0.7 millimeter (0.03 in) thin yet rigid supporting material, flexible substrates such as thin glass, plastic films or metal foils may be used, which can be bent in one or several directions. This new potential provides greater styling freedoms for rear light designs. The technology’s key characteristics are retained as well as the low weight of the existing two-dimensional OLED displays. For the first time, the light emitted will be able to shine in a three-dimensional way. Flexible digital OLEDs facilitate the integration of the “display area” all the way into the vehicle’s flanks, thereby visibly enlarging the usable area for lighting design and communication with the surroundings once again.