The ISLE project was financed by the 6PM a European organization. It belongs to the program called Design and manufacturing technologies to improve vehicle/vessel interfaces.
Developement of an innovative manufacturing technology to produce a new generation of headlamps for vehicles, which will be the basis for a future car-to-car or car-to-infrastructure communication system
The state of the art in lighting is an electric bulb. But these bulbs cannot be modulated, so they are of no use for communication. White LEDs are in existence today and could serve for both purposes. A standard incandescent bulb achieves 20 lumens per watt (lm/W) while automotive xenon lamp technology provides 90 lm/W. Solid-state technology currently achieves up to 40 lm/W in laboratory quantities and about 20 lm/W in series production. New records are established every three months. The theoretical limit of 200 lm/W means the solid-state source achieves greater efficiency than the best existing light source. More efficient lighting systems would mean an enhanced brightness on the road while reducing fossil fuel emissions through lower power consumption.
The main objective is to define the ability of an LED system to provide communication modes for other vehicles or traffic safety devices – measured by the new ability to communicate during different driving conditions. This will be achieved by:
- validating the chip-on-board LED array with a primary optic moulded over the LED array, measured by an automotive qualification schedule
- researching the best methods for converting multiple blue chip array into white chip array, measured by meeting colour temperature and rendering requirements
- defining the best colour temperature and rendering for automotive driving
- creating the most efficient optical system while understanding system trade-offs, measured by optical simulations and photometric measurements
- defining the best method to electrically drive an LED system and integrate electronics in a vehicle format with respect to the modulation of the LED-array for communication
- developing over-moulding technology for chip-on-board modules to produce a complete lamp within one injection-moulding shot
- creating a system integration for the ISLE project in an automotive environment, measured by cost studies and automotive qualification schedule.
Description of work
In the first phase, the consortium concentrated on finding convertible concepts, which meet both the individual excellence of each partner and the overall project goal. The central elements were:
- the LED architecture with respect to the requirements of the beam pattern forming optical elements
- finding a suitable possibility to perform communication without any losses in light
- definition of the required components
- efforts in making LED headlamps legal.
The work was organised and the interfaces defined, the best suitable concepts were selected and implemented accordingly. From the first results optimisation loops have begun.
Results achieved so far:
- first samples of white LED have been manufactured performing with a correlated colour temperature below 4 500°K
- the communication concept has been implemented and its feasibility was approved in the laboratory
- the integrated optical concept, which is based on the coupling between refractive and reflective optical components, was turned into a first sample for a high beam module and the low beam is on the way
- a novel concept of laminating high-reflective coating on plastic optics was developed to substitute Al-coating
- an electronic driver circuit on a lower scale integration with all the necessary functionality was developed
- a liquid cooling system for the thermal management inside the headlamp was developed.
Expected end results
At the end, the consortium will present a fully functional headlamp device using LED as a light source, performing a high and low beam. The out coming light will be able to be modulated in order to communicate information to the infrastructure. The device will provide outline dimensions in accordance with the space generally available in today’s cars. It will be capable of being mounted on a test rack in front of a vehicle.
It is expected that the additional knowledge built up during the project will enable each partner to have further commercial benefits or, in case of public bodies, reputation and contacts with industry.