In the future, not only LEDs, but also textile fibers are to create the right atmosphere in the car's interior.
In the future, not only LEDs, but also textile fibers are to create the right atmosphere in the car's interior.
( Source: Salewski/Munda)

Automotive suppliers

Light transmitted through fibers promotes individuality in the interior

| Author/ Editor: Gerald Scheffels / Jochen Schwab

A supplier of interior textiles and a specialist for interior lighting have combined their know-how by establishing a joint venture that introduces new design freedom to automotive interiors in the form of textile light guides.

Development, manufacture and supply of textile lighting systems: This is the business objective of the newly founded Munda Textile Lichtsysteme GmbH. Aunde and Mentor are equal partners in the joint venture, and the German Federal Cartel Office has already given its approval.

Aunde contributes its know-how in the field of technical textiles to the new company - in addition to its network in the process chain of interior components. The company, which was founded in 1899 and has concentrated for decades on yarns, technical textiles and seat covers, has enjoyed strong growth through acquisitions. Aunde has gained a strong market position as a manufacturer of complete seats and interior modules, especially through the integration of the Isringhausen and Fehrer brands. 115 plants in 29 countries and more than 24,000 employees ensure a worldwide presence close to the car manufacturers.

The other partner, Mentor, is known in the automotive industry as a specialist for interior lighting solutions. Storage compartments, armrests, door sills, consoles or instrument panels: LED-based color light from Mentor is used as surface, line or point light and is controlled via the corresponding RGB base modules.

Demand for individual lighting

Originally, interior lighting served exclusively for orientation purposes. Nowadays, it is not only about function, but also about emotional aspects such as well-being and quality. The demand for individual lighting, which can be adapted to the driver’s preferences, for instance, is also gaining in importance. Moreover, dynamically adaptive color light scenarios are demanded that cover as large a range as possible in the RGB color spectrum (color mixtures of red, green and blue). Mentor has developed an automotive RGB LED solution for these applications that is based on an intelligent RGB base module with integrated micro-controller.

However, there are also some restrictions caused by the light guide. Benjamin Mohr, Development Manager of Munda: “The current standard are guides made of plastic injection molding, which are only flexible to a limited extent. This requires expensive tools, which are only profitable for large quantities. The distance between the light source and the light outlet is also a limiting factor.”

Light guides in fibers

These disadvantages do not apply to the textile light guides Munda will use. Benjamin Mohr: “They have a very similar structure to the optical fibers used for data transmission. A fiber core made of PMMA is wrapped in a cladding. The fiber directs the light according to the principle of total reflection. Wherever the cladding is removed, light is emitted.”

These types of light guides can be connected to several sources. In this way running lights and color scenarios are created. Because they are flexible, they can be integrated into soft materials and incorporated into almost any contour: “We can backlight textile surfaces and illuminate every edge of a surface lighting,” says Benjamin Mohr. The light-guiding fibers provide designers with new design options and developers with flexible handling of the limited installation space in the interior - without component-specific tooling costs. Another possibility is the coupling of the lighting control with sound systems or vehicle data - to name just a few examples. Functional signals such as those from the Lane Change Assistant can also be easily transferred from the exterior mirror to the vehicle interior.

The division of labor of both companies will look like this: Aunde supplies the light-conducting fiber mats in rolls, Mentor the RGB modules. At Munda in Erkrath, the fibers are bundled, connected to the light injection module and completed to form a functional system. The lighting systems can then be integrated into the component either by a supplier of the Aunde Group such as Fehrer or by an external customer in the interior industry.

Considerable changes in the interior

With the founding of the joint venture, Aunde and Mentor are also targeting the autonomous driving market. Rolf Königs, CEO of the Aunde Group: "This megatrend and other developments will change the vehicle interior considerably. With textile lighting systems we meet these new requirements and help to create completely new customer experiences." The two companies are aiming for growth. Wido Weyer, Managing Partner of Mentor: “The technology developed at Munda opens up new fields of applications for us - not only in the automotive industry.”

This article was first published in German by Automobil Industrie.

* Original by Sven Prawitz, Translation by Alexander Stark

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