Exciting new design possibilities
Translucent surfaces now also available for large-format plastic components in series production
Light design is becoming a key tool for brand differentiation in the automotive industry. A new laser technology now makes translucent surfaces possible even for large-format plastic components and geometric deviations - in fully automated series production.
Car manufacturers are working intensively on redesigning their vehicle range visually and emotionally. The aim is to rekindle the love of the car. In doing so, they are focusing on new drive and future technologies as well as design. This combination opens up the large market of surface backlighting, especially for electric vehicles. To summarize: The automotive future is shining.
"You can already see illuminated components on the road in many Asian countries," says Nicolas Kroth, Area Sales Manager of JENOPTIK's Laser Processing business unit. "European and US OEMs want and need to keep up in order to remain competitive." Dominik Friese, Head of Development at RESRG Automotive (formerly Rehau Automotive), also confirms the demand: "The market for backlit design elements on and in cars is there. And it is growing. At the moment, however, we are being overtaken on the right by Asia. The German concept cars are already on sale there as series vehicles. We have to find the gas pedal."
True to its claim "More Light", Jenoptik AG is supporting the global trends in lighting design in the automotive industry with its JENscan Style translucent technology. The laser system produces translucent surfaces by removing layers of paint from large-format three-dimensional plastic components - for example from bumpers, tailgates, spoilers, front panels or headliners.
Lighting design as a vehicle for emotion
"A car has to look futuristic these days. It has to flash and sparkle," says Nicolas Kroth. "The brand identity can be conveyed via an illuminated brand logo, for example." In addition to the logo, shapes and colors also convey the characteristics, values and messages of a company or product. Lighting design is therefore a powerful tool for this creative transfer of information and feelings into visuals.
"We succeeded in using light as communicative decoration for the first time with the Cupra "DarkRebel" show car," says Christian Döring, Technology Developer for Lasers and Optics in the Application Center of Jenoptik's Laser Processing BU. "We have transferred the luminous optics of the Dark Rebel concept into reality with the help of translucent technology." In the future, light will play a decisive role in differentiating automotive brands. The reason for this is that equipment and technical standards are becoming increasingly similar.
"Electric cars can only have a low level of drag, so it is not possible to individualize the car through its exterior design," says Nicolas Kroth. "This is where design with light creates new possibilities." Light is therefore one of the few remaining distinguishing features of electric vehicle brands. It is becoming the central instrument for recognizably differentiating and designing brands and models.
RESRG Automotive confirms suitability for series production
The buyer of the first JENscan style system was Rehau Automotive, one of the five largest automotive suppliers of plastic exterior components. Following a merger in the second quarter of 2025, Rehau now operates under the name RESRG Automotive. The company connected the JENscan Style to the paint line of its own R&D production line back in 2024. The purchase was prompted by the specific interest of a major German car manufacturer in backlit bumpers. "We wanted to demonstrate the machine in the process chain and show that everything works," says Dominik Friese. "We have already proven that the system is suitable for series production. Customers can also visit our factory to see how the paint is precisely removed from the plastic components at the points where light is later to shine through."
The demand for translucent surfaces from OEMs is high, and all painted plastic components are suitable for implementation. "The JENscan Style laser removes paint from predefined areas and I can backlight the recessed shapes with various colors. This gives me a completely new visual appearance on a large surface - with significantly fewer components, joints or edges."
Products currently in high demand include radiator grilles for electric cars. The panels, including bumpers, are finished with paint and backlit as a central component. "A major benefit here is the 3D processing of the geometrically demanding large components," says Dominik Friese. "Jenoptik's translucent technology provides an extremely high degree of freedom to incorporate fine, intricate symbols and patterns, which are then backlit."
The challenge: processing deviating components
Laser machining of plastics is a challenge, as the components involved are susceptible to variations. The aim here is to deliver a precise result despite the given component tolerances. "Processing the surfaces manually would be very time-consuming and, not least, harmful to health," says Torsten Reichl, Product Manager for the JENscan Style. "In addition, the deviations in thickness, shape, paint and position can hardly be compensated for by hand." The laser beam, on the other hand, processes the component surfaces precisely and highly efficiently.
The next component for backlighting are polypropylene bumpers. They are large, three-dimensionally shaped and flexible due to their material properties. A serially produced bumper is rarely identical to its original CAD model because it warps, shrinks or otherwise changes during the manufacturing process and further processing due to deformation or thermal influences. All of these properties pose a challenge for the machining of such components. "In Jenoptik's Laser Processing business unit, we have created an optical-digital solution for providing these differently delivered components with a uniform laser ablation," says Torsten Reichl. "The 'Active 3D Alignment' function ensures precise laser ablation through optical measurement and thus leads to reliable precision.
Solution: digital adaptation follows optical measurement
The JENscan-Style technology takes into account individual deviations in series-produced components. The process is as follows: In the paint line, light-blocking primer is applied to the components from a transparent substrate and painted in the desired color. This is followed by the JENscan style process, in which the system vaporizes the pre-programmed pattern from the paint, i.e. partially removes it. To do this, the component is fixed in the system on a fixture so that it can be reached by the robot's processing head from any angle. It is automatically measured in this fixture. The special challenge lies in the fact that each component has to be processed individually due to its deviations from the original model. A multi-stage sensor system, consisting of an optical sensor and cameras, records the component deviations and adjustment algorithms digitally compensate for them in comparison to the CAD reference. The desired pattern is then re-projected onto the individual component. Theory and reality are virtually superimposed and adapted to each other.
During laser ablation, the robot adopts different poses. "In each processing pose, a fast 3D scanner moves the laser beam over the component to remove the paint in the desired pattern," says Torsten Reichl.
Active Stitch technology, the laser can always restart in exactly the right place between two poses so that the patterns merge seamlessly." This enables precise processing of the large three-dimensional components. As a result, the system creates the precisely reproduced pattern on each of the differently shaped components. The component is then coated with a clear lacquer in the coating line, which evens out the height differences within the surface and seals it. Once installed, the deviations in production are no longer visible
Consistent lighting design on bumper surface
Bumpers are the largest and most sophisticated components of a car that are currently backlit. The JENOPTIK Laser Processing BU team is already showing a processing example at the Shanghai Auto Show. "We have provided the entire bumper with a homogeneous pattern throughout," says Nicolas Kroth. "Unlike other laser technologies, the JENscan Style motion system reaches the surfaces of the three-dimensional wings. The pattern therefore actually extends from the far left to the far right." In addition, a continuous light strip adorns the bumper. "Light bands are an absolute design trend," says Torsten Reichl. "We integrate them directly into the component. This eliminates the need for the light guide as a separate injection-molded element. This saves several process steps and therefore costs in production. The laser-cut solution also supports aerodynamics, as there are fewer slits and joints. This also results in a very clean front with a seamless design."
The machined bumper is the near-series prototype component of a major German OEM and is characterized by a particularly thin middle zone. "The torsional inclination of this format posed a challenge for the bearing of the component within the system," says Torsten Reichl. "But we were able to fully stabilize and machine the bumper." A special feature of the design of the exposed bumper is the point removal. Similar to a classic print grid or the pixels of digital images, the paint on the bumper was only removed in spots and not over the entire surface. In this way, the bumper appears classic, black and inconspicuous when unlit. Only when the lighting is switched on does the contrast effect make the lighting design the center of attention. The Jenoptik Automatisierungstechnik laser processing team will be exhibiting the bumper again at the K trade fair in Düsseldorf in October 2025.
Outlook: Car-to-pedestrian communication
There is still a lot to be done in the automotive industry in terms of emotionalization through lighting design, be it through color or animation - after all, the majority of applications in the industry serve to evoke emotions. "Ultimately, a car sells itself through its design," says Dominik Friese. And in the course of the electrification of road traffic, more components that are still made of metal will be made of plastic in the future. This reduces weight, which is relevant for the electric drive. At the same time, they enable backlighting.
The current vision of the automotive industry shows a single illuminated front, consisting of a bumper and inconspicuously integrated headlights. Jenoptik's translucent technology also offers the opportunity to implement another trend - mass customization, i.e. the combination of a mass product with customer-specific individualization. With the help of JENscan Style, components in series production can be processed with different design patterns so that they are individually designed. Light design could also be used to adapt vehicle models without the need for new injection molds or tools for production. The mass product can be adapted or individualized in one and the same system.
In addition, translucent technology enables safety-relevant communication between autonomous vehicles and their environment. "By the fifth stage of autonomous driving at the latest, lighting design will play a decisive role in car-to-pedestrian communication," says Nicolas Kroth. Light will then become a functional information carrier. Clear and unambiguous communication between the self-driving cars and the people around them is necessary in order for pedestrians, cyclists and autonomous vehicle drivers to move safely and confidently in autonomously dominated road traffic.
RESRG Automotive is already planning a specific new surface application for the JENscan style technology. Instead of paint, foil will be used to decorate the component surfaces. "In contrast to paint, I can use films to display multi-colors. The wilder the pattern, the more advantages the films offer." The films are printed with a motif and inserted into the injection mold to be applied directly to the component. Lacquers, on the other hand, are still suitable for large or single-colored surfaces. "With our laser system, we can remove the films just as well as paint and offer our customers both options." In the future, such a laser ablation system could also be integrated into a painting line and process components directly in the painting skid so that they no longer have to be ejected. This integration would be the final step towards fully automating the production process for painted components with a light design.
The technology is suitable for all coated three-dimensional surfaces in various areas of application, be it aircraft parts or bathtubs. "Wherever translucent surfaces contribute serially to a personalized feel-good ambience, individual therapy or brand communication with light," says Nicolas Kroth. "There will be some new impulses here that we haven't even thought of yet."