Dearborn, MI, - The first day of the 13th Annual Symposium on Vehicle Displays, being held at the University of Michigan Fairlane Center, concluded yesterday with a panel titled "Are OLEDs Suitable for Automotive Applications?"

Ken Werner
Senior Analyst and Editor
of HDTV Retailer and
Mobile Display Report

In answer to several audience questions, panelists Steve Bower (Delphi Electronics), Ben DiCicco (DaimlerChrysler), Joe Gasiewicz (Yazaki North America), and Hiroshi Araki (Nippon Seki) made clear that for the automotive industry today, "OLED displays" means monochrome alpha numeric displays.

Monochrome passive matrix is what has been used by Astin Martin in the DB9, DaimlerChrysler in the Jeep Cherokee and by GM in the Corvette, said Gasiewicz. "Active matrix OLEDs are out of site [as far as price is concerned] and color is not automotive-ready," added Bower.

So, are monochrome passive matrix OLEDs suitable for automotive use? "Potentially yes," said Bower. "It’s an easy sale to customers. The only issue is cost." Unfortunately, cheaper passive-matrix OLEDs don’t have adequate reliability. "We need an inexpensive automotive-grade version."

Gasiewicz added "that OLED system costs for these displays is 2.5 times that of a vacuum fluorescent display" (VFD). Bower said, "the simpler the display, the harder it is to justify the higher OLED cost."

Lifetime was discussed extensively, and the consensus was that for the current monochrome displays, lifetime is adequate. To illustrate the lifetime issue, Araki and his colleague Yutaka Shimotori, showed a display that had characters intentionally burned in. The burned-in area had 30% less luminance than the remainder of the display and was obvious when all the display pixels were lit. But when the display was used in its normal mode - characters formed by lit pixels against a dark background - the fatigued areas were not visible, even to the expert audience clustered around the demonstration. This demonstration provides a cushion on lifetime requirements.

Audience members and panelists, including Universal Display Corporation’s Mike Weaver, agreed that the currently used specifications for OLED lifetime - which is the time it takes for the display’s luminance to drop to ½ half the original value - is not in accord with the automotive industry’s needs. For the automotive industry, it was generally agreed that "lifetime" should be specified to 90% of original luminance, a more stringent definition.

The price issue was not accepted as being an overwhelming issue by some of the panelists. DiCicco said in particular situations, the pricing is manageable, and DaimlerChrysler is considering OLEDs for vehicles other than the Grand Cherokee, and they are investigating the applicability of monochrome graphic OLED displays now.

And Araki said he doesn’t think cost is necessarily a problem. "Just send us your RFQ (request for quote)," he said, to good-natured laughter from the audience.

Despite the interest for OLEDS for automotive use exhibited in Dearborn, it was clear that Passive LCDs and VFDs will be the dominant alpha numeric displays in automobiles for years to come. -KW