Your interior displays reflect the character of your vehicle. A car that might look good from the outside can lose a lot of its appeal when the prospective buyer gets in and is confronted with an antiquated, hard-to-read instrument cluster. And if they are in the high-end market, they're going to expect more than a speedometer and a gas gauge. If a customer is being asked to shell out $30,000 or more, they're going to expect displays that provide safety indicators, outside temperature, directions, advanced audio system information, notifications of incoming phone calls or e-mails, video and more — all easy to read, integrated, configurable and legible in any ambient lighting environment, even bright sunlight, and from any angle.
Having just the right look, while providing the functionality needed or desired by the driver, is critical to your design. Today's vehicles include a wide array of technologies.
The predominant technology being used in these configurable interior displays is a liquid crystal display (LCD). Today, an average of two or three are installed in a car when it leaves the factory. All of those displays must be subjected to environmental tests under actual driving conditions to confirm their suitability for onboard automotive use. Different display manufacturers have their own evaluation criteria, and the automotive design engineer needs to know that these criteria are strict and exacting, drawn from research and development. If the early estimates from the display manufacturer's various acceleration tests have consistently proven to be correct, it saves the automotive engineer a lot of time and trouble down the line.
Typically, the arrangement of automotive displays is concentrated in the instrument panel in front of the driver and in the center portion of the console, where there is ample installation space. Some heads-up displays integrate into the windshield, and other displays are embedded into the rear-view mirror. Each display may have to meet different requirements, depending on its purpose. Engineers must consider the best locations for in-vehicle displays, the best kinds of information for those displays to present, and what type of LCDs to use.
Reconfigurable automotive super-twisted nematic (ASTN) LCDs allow one cluster to be used for various locations. Instead of having dedicated appliqué indications for regional requirements, reconfigurable displays can be software programmable at the instrument cluster factory. ASTN LCDs also give the cluster maker the option to use the same display across many vehicle platforms. For example, the same ASTN display could be used in a cluster with a red-colored backlight and in a cluster with amber or white-colored backlight. High-performance color LCDs can bring out that vivid color accentuation or audio system displays while remaining black in the off state. For infotainment displays used in center consoles and rear-seat entertainment displays, a variety of standard and semi-custom thin-film transistor LCDs are available.
A technology called Mechatronics enables unique, reconfigurable instrument panel designs that provide high-information digital content while keeping the classic design of instrument cluster panels using pointers. Mechatronics can provide holes in any kind of LCD, which offers instrument design advantages, including the ability to change language, county or engine version information by changing the software. Mechatronics also provides flexibility in the location of analog and digital information areas. The area behind the pointer sweep can be used for multiple information displays such as text messages, status icons and navigation information.
Optrex is pioneering the next generation of emissive technology — organic light-emitting diode (OLED). OLEDs are composed of self-luminous pixels and require no backlights. They provide clear, bright, full-motion image display viewable from a wide angle, with fast response times, high brightness levels in a variety of lighting conditions, and low power consumption. OLEDs that provide up to 128 multiplex ratio, meet automotive environmental requirements, and provide up to 30,000 hours to 80% of original luminance are being used in production vehicles such as the Jeep Grand Cherokee and Corvette.
ABOUT THE AUTHOR
Dale Maunu is director, marketing, procurement, MIS & contracts for Optrex America Inc., Plymouth, MI. He is the author of published articles on displays, and has extensive experience in the flat panel display industry.