The existing CIE evaluation method, referred to as TC4-45, defines the range of the light distributions on low and high beam in defined zones, such as the right and left edge of the road, lateral illumination at different distances, etc.
In the newly proposed method, the same zone criteria from TC4-45 allow an absolute evaluation of the range gain from glare-free high beam (ADB). The criteria Zone A (range at right-hand edge of road), Zone B (range in curves) and Zone C (range at left-hand edge of road) are particularly suitable for this purpose.
This new method is based on the recognised evaluation principles from the CIE standard TC 4-45 and the legal requirements according to U.N. Regulation 123. The evaluation is based on an extensive database of a wide range of headlamp systems and test series, so that in conjunction with the extensive ADB database developed, reliable results are achieved for all systems.
The four takeaways of the proposed evaluation are:
• The proposed rating system makes possible, for the first time, qualitative evaluation of not only static low and high beam, but also the glare-free high beam.
• The objective result quantifies the safety performance achieved by the headlamp system.
• The method, based on laboratory measurements, thus leads to representative results that allow a direct and objective comparison of different headlamp systems.
• The classification into different classes (Standard … Premium+) allows to present the safety performance of a headlamp system in a manner accessible and understandable by non-experts.
Questions to Prof. Khanh about the rating system
With his Ph.D in optical spectroscopy, Prof. Khanh headed photometry and colourimetry laboratories at companies in Berlin and Munich. From 2000 to 2006, he was project leader at Arnold & Richter in Munich. Since 2006, he is Chair of the Laboratory of Lighting Technology at TU Darmstadt, and in charge of the renowned International Symposium on Automotive Lighting.
DVN: As one of the leading developers of the new rating system, what do you consider the most important from this assessment?
Prof. Khanh: First i have to say that the vehicle lighting industry has been dealing in the last 20 years with light sources, headlamp technologies (free-form optics, pixel light) and design of the light units. Now, the main substance of the research and technological development is (and should be) the automatic generation of new light distributions—not only low or high beam, we need the flexibility of ADB—changing dynamically in accord with the actual traffic situation in the traffic space in front of the vehicle, and evaluation of these dynamic light distributions. We go more to the light and less to the technology. For this primary aim, we need a new rating system with safety as the key parameter. The main point of this new rating system is to keep the principle of CIE 4-45 and to expand the evaluation to the ADB context based on weighting the use frequency of ADB. This new rating system has been validated with 17 different headlamp types.
DVN: Do you think it’s possible to make more progress before the ViSION congress in October?
Prof.Khanh: yes, a number of automakers and set makers will have a task force group meeting in September in Darmstadt. We have to optimise, improve, and numerically correct the evaluation by a collection of a number of headlamp luminous intensity curves (in IES-format) from different manufacturers and to evaluate them.
And we have to validate this evaluation by real test drives this August-September. With selected headlamps with well-known lighting distributions, we from this task force will start a series of night time driving tests and the test drivers and members of motor journals should evaluate subjectively the impression regarding contrast (visibility level and distance) and the brightness of the light distribution close to the car (3 to 32 m in front of the car) and beside the own lane.
DVN: The special session on rating systems you will chair will be an important part of the VISION congress. What do you expect from this session?
Prof. Khanh: with German manufacturers and with some automakers with research and production activities in Germany, the consensus has been achieved this past January-February by a first meeting with more than 25 experts in Darmstadt. More tests and evaluations are needed, and the test results should be reported in this VISION session to give attendees from over the world an understanding and basis for acceptance of the new rating system and to recognise the advantages of ADB-Technology.
DVN: Do you think it will be possible to convince the lighting community of this rating system’s merits? What should be next action?
Prof. Khanh: The problem with CIE 4-45 was that this topic stayed in the frame of CIE and within a small group of experts. In the last decades, the evaluation and rating of lighting distribution was not the focus of the community. This situation has been changed in a positive manner. Yes, rating of the light is important for car makers and car users and now an important marketing and technological argumentation. The mental condition in the vehicle lighting industry has achieved a new dimension. With the new rating system, we have to communicate with important countries like the USA, China, Japan and South Korea in the frame of GTB/GRE and also outside between experts. I do not see big content problems between this new rating system and the current activities in the similar direction in China or Korea.
Questions to Rainer Neumann about the rating system
Dr.Rainer Neumann started in 1984 at Bosch then moving to MM. He joined Visteon and became VP Global Technology. Rainer Neumann is Member of Scientific Committee in VISION, ISAL, ISOL, and IFAL. He was awarded as the Personality of the year in Automotive Lighting by DVN in Paris in 2014.
Rainer Neumann chairs the research WG SVP in GTB, is Co-chair of the WG Strategy and belongs to the international Automotive Lighting and light– Signalling Expert Group (GTB)
DVN: As one of the leaders of the new rating system, what are for you, the main data coming from this assessment?
Rainer Neumann: The new rating system is taking into account the safety relevant photometrical data to be able to detect objects and beeing able to react accordingly in time and avoiding accidents in night time driving. It is taking into account for the first time the important adpative driving beam system (ADB), which works automatically and results in an optimized illumination of the road ahead without glaring other road users.
DVN: Do you think possible to convince the lighting community at this rating system? What should be next action ?
Rainer Neumann: We have already a big support of the new headlamp safety Performance Rating system from the automotive lighting industry in Europe. First publication by the university in Darmstadt (lighting Technology group of Prof. Khanh) will be published in ATZ in the next month. Additionally, we also need to communicate and involve automotive journals in the public our new rating system to get suppoprt and to create awareness and acceptance.
DVN: The intention of GTB is to establish a working group to develop a globally acceptable NCAP assessment for Lighting. Where are you in this process ?
Rainer Neumann : We are at the very beginning ! Based on the scientific based continuation of TC 4.45 we need to explain in an easy understandable way, that the objective criteria which the rating system indicates are also reflecting the real impression of a driver when driving at night.
We plan to install a data base at a neutral, objective place (university), where all new approved headlamps with the new rating system can be stored and distributed and published.
DVN : What is your feedback about the IIHS and the Consumer Report rating systèms?
Rainer Neumann: IIHS has presented a simple model by taking just the vehicle from the dealer and checking glare and detection measurement points. It is simple and has been successfully introduced in the market. The fact, that the evaluation is arbitrary and influenced by a lot of parameters, which have nothing to do with the headlamp light quality is obviously not that important.
Same with the consumer report rating, which is very popular in US :
For our targets we can learn that good marketing and simple communication tools are necessary and important to be succesful in the future.