Enhancing Cabin Ambiance &
Functionality with Ultra-thin & Flexible LED Lighting

A Project between Webasto and designLED


LEDs have become more popular in automotive interior lighting as they can create an immersive illumination experience that enhances mood, wellbeing, and comfort. Besides offering an effective brand differentiation, they can also improve driver and passenger awareness of external obstacles through visual cues. Whether for luxury, infotainment, or safety use cases, interior lighting is becoming a must-have feature in automotive design.

Since LED technology is more configurable and lasts longer than incandescent lights, it enables automotive players to create various ambient lighting designs in the car. A world market leader in vehicle roof systems, Webasto was also looking for new lighting features and applications in the car roof area, such as ambient lighting. Having been introduced to designLED, a startup specialized in LED applications, via STARTUP AUTOBAHN, Webasto’s Advanced Engineering Department in the roof business unit soon decided to conduct a pilot project for a convertible application. The goal was to create a dynamic lighting concept and prototype for interior lighting for use with translucent surfaces in a convertible headliner.

Through this collaboration, they wanted to introduce RGB dynamic light on the interior trim materials of an automotive headliner. The challenge was in the creation of uniformly illuminated surfaces using semi-transparent and textile materials. While Webasto’s prototypes had demonstrated the concept, designLED had to improve uniformity and high-quality appearance, without increasing the system thickness.

The Project

The agreed scope of the project was in the creation of conceptual demonstrators. Following evaluation of materials provided by Webasto, designLED would design custom LED light-guides, which employed designLED patented optics to remove the visible artefacts, enabling the demonstration of uniform luminance with the Webasto materials. Key criteria were thinness, uniformity, and perceived quality. Thus, the project was executed as follows:
▶ Webasto’s team provided design intent and key objectives, as well as the Class A surface materials and the main convertible headliner component.
▶ designLED’s approach was to explore the design feasibility of illuminating these materials by

a) testing various optical designs and mechanical concepts to explore system design boundary conditions, and

b) creating a top-level design concept and agreeing on a technical specification.

▶Subsequently, designLED developed light tiles with a custom optical design, a mechanical integration route, and custom animation sequences.
▶ To explore the potential for light integration with these materials, and simplify the construction of the POC, the design team chose to illuminate multiple, smaller areas rather than whole headliner. For the serial production, the idea would be to cover the whole area of the trim part with the Class A surface and integrate designLEDs dynamic RGB light tiles behind it.


As of May 2021, the joint team effort has resulted in the successful development of a prototype. Specifically, they developed dynamic RGB illuminated convertible headliner components with integrated light tiles. These pieces were integrated with Webasto’s decorative wood-plastic hybrid Class A surface materials. In the end, design-LED achieved a daylight visible luminance of > 500 cd/m2 , a high level of homogeneity of > 90%, and a light tile thickness of < 3mm. Moreover, this project also allowed them to explore illumination through composite wood-plastic materials that offer a high level of transparency to reduce power consumption.

Future Outlook

The next steps will be to design and build further POCs, explore HMI by using transparent touch sensors, and extend the concept to cover the whole headliner. Apart from discussions about additional applications, Webasto also intends to seek validation from their customers to see whether the technology could be further developed into a serial product. After all, creating beautiful visual effects with dynamic lighting in the convertible roof could engage and inspire vehicle occupants.


We would like to express our sincere thanks to Franz Haberl (Webasto), Thomas Hemauer (Webasto), Dr. James Gourlay (designLED) and Tony Allison (designLED).


STARTUP AUTOBAHN powered by Plug and Play is an innovation platform moderating an in-depth and curated collaboration between core partners from industry and young tech companies.The program is stage agnostic and designed to accelerate startups by connecting them to the right business units of our Corporate Partners in order to lay the groundwork of a successful cooperation and eventually outstanding pilot projects, implementations or investments.

Plug and Play Tech Center, Mercedes-Benz AG, ARENA2036, University of Stuttgart, ZF, DXC Technology, Porsche, BASF, Webasto, Motherson, DPDHL, Bosch, Schaeffler, STMicroelectronics, Murata, AGC, Hyundai, Linde, BP, Wieland, Faurecia, Eberspächer, ADAC, Sekisui, Plastic Omnium, Zenzic, Maxion, Novelis, ITT, Grupo Antolin, Huf Group, CEAT



Contact for this project

Theodora Alexe
Ventures Associate,
STARTUP AUTOBAHN powered by Plug and Play

Thomas Hemauer
Corporate Strategy Manager,
Webasto Group



STARTUP AUTOBAHN powered by Plug and Play

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