OLEDs—organic light emitting diodes—are light-emitting panels made from organic (carbon-based) materials which emit light when electricity is applied. It is the only technology able to create large lit areas, as opposed to LEDs which are more point-emitting.
Organic materials to emit light have been used with great success since 2004 with passive matrix and since 2007 with active matrix for TVs, and more recently since 2010 for smartphones.
But attaining the reliability and robustness needed for exterior vehicle lighting took a great deal of time and effort.
Many suppliers have worked to develop OLED lighting—GE, Philips, Osram, LG, Konica Minolta, Panasonic, NEC, and others. But almost all these companies stopped their OLED development, mainly because it would have required big investments with an uncertain market adoption due to stiff competition from less costly, more advanced LEDs.
Car OLEDs had a good start in 2016-2017 with the launch of the Audi TT RS and the BMW M3 CS, both with Osram OLEDs, and the Mercedes S-Class with LG OLEDs. But Osram stopped making OLEDs, BMW pivoted to laser light guide rear lamps, and Mercedes concentrates on microLED headlamps with projection. Audi alone continued with OLEDs, with LG panels until that company exited the OLED business, and then with OLEDWorks.
OLEDWorks was established in 2010 by former Kodak experts. Bolstered by buying Philips’ OLED department in 2015, they delivered their first car OLEDs in 2022 for the Audi A8.
Around the same time, Yeolight—established in 2001 in China to develop PMOLED and AMOLED displays—developed OLEDs for lighting, including for cars. Their first such application was on the Hongqi H9 in 2020, and they are now working on other new projects.
OLED panels are unanimously appreciated for their very nice homogeneity and the freedom they offer for the shapes of the illuminated panels. They are also very light and thin with less than 1mm thickness. They are power-efficient, particularly compared to ‘OLED-like’ LED setups which generally have very low efficiency of around 10 per cent. In parallel, from the initial orange-red colour, the trendy red-red colour is now available. From an initial brightness of 1,000 cd/m2, they are now able to deliver 2,000 cd/m2 as demonstrated by OLEDWorks on the Audi A8 in 2022, making them perfect for the likes of tail lights.
And OLEDs are perfectly adapted for digitalisation. They can produce displays with a good definition done by six, 60-segment panels as seen in the latest Audi Q6 e-tron. So, specific light signatures chosen from a smartphone, more attractive welcome scenarios, and safety messages for following drivers are now possible with OLEDs, giving them a complementary attractiveness.
With all these qualities, one could expect a rush for OLED adoption, but that was not the case till now. Of automakers selling vehicles around the world, only Audi equip massively their cars with OLEDs, with a take rate at 100 per cent for the A8 and between 10 and 25 per cent for the other cars.
Certainly, the main reason for the low adoption rate in the past is that OLEDs had historically high costs, with an estimation by DVN at around €1/cm2, and even that steep figure is down 60 per cent since the introduction in 2016. This means OLEDs were pretty much economically feasible only on premium cars, but as volumes have increased and continue to increase (for example from the TT to the A8 to the Q5), costs continue to decrease with very significant further cost decreases due to volume alone expected by 2027-2028. As with all new automotive technologies this will drive the adoption of OLED lighting from premium cars down to lower cost, higher volume cars during that time and beyond.
There are other limitations as well, but they are gradually being broken through:
- Available output: 10,000 cd/m2 is announced for red OLEDs and 20,000 cd/m2 for amber ones, opening the door for OLED stop lights and turn signals.
- Curved Panels: prototypes of flexible panels have been presented, that could be transparent in the future too, offering new styling possibilities.
- And for digital displays, OLEDs can reach a pitch of 10 μm, the limit of lithography to deliver high- definition displays, perhaps in the future with thin-film transistors (TFT) for the electronic controls to simplify the circuits and harnesses, which can be complex and expensive right now.
With all their technical qualities and with cost decreasing, with their new digital abilities to display information where they are there totally cost competitive, OLEDs could catch the trend to use more and more displays in and around cars. For the more traditional uses for tail, stop or turn indicator, it is possible to think realistically that the OLED cost penalty could ease off. Especially given the surge of interest for OLEDs now, particularly in China where several car makers are preparing new models with OLEDs.
So, there will be a future for OLEDs in exterior lighting. But what will that look like? How broadly will they proliferate, and how fast? Up to now, low volumes drove high prices, which put a brake on adoption, but now a virtuous circle is set in motion: price reduction will attract more applications, which will increase volumes and drive prices down. Most lighting suppliers expect OLEDs to increase their market share, but remain confined to high range cars for the foreseeable future. Today’s figure is less than 1 per cent in the global car market, and growth by 2030 to 3 per cent of worldwide market share, mainly in Europe and China, could be expected. But if important cost reductions occur with the current evaporation process, as current OLED manufacturers anticipate by 2027-2028, or if a breakthrough like inkjet printing processes (as used in other OLED applications) could be adapted to the severe specifications of the vehicle lighting realm, most likely after 2030, that could greatly accelerate adoption.