Globally, design engineers need displays that can perform consistently in extreme applications as diverse as aircraft auxiliary power units, commercial freezers, retail and industrial gas pumps, fuel and water meters, portable emergency respiratory care and non-climate-controlled facilities.

This growth in demand for "extreme" user interface technology is due in large part to recent technical advancements that have dramatically enhanced the reliability, visual performance and cost-effectiveness of LCD technologies that operate in extreme heat and extreme cold. To maximize the benefits of these technology developments, engineers should consider five key points when designing user interfaces for use in extreme conditions.

Tip 1: Select technology best fitted to your environment
In order to create a successful product design, a vital first step is to have a clear understanding of the environment your technology will need to perform in. It is important to know what type of temperature range the user interface technology will experience in both storage and operation as well as to anticipate any additional environmental impact from elements like wind and product vibration.

A comprehensive understanding of environmental challenges will help in the selection of user interface technology best suited to each application. Currently, several off-the-shelf LCD technologies are available that perform in the -20°C to +70°C temperature range. Recently introduced products allow for the production of cost-effective custom LCDs that provide reliable performance from -40°C to +85°C.

Extremely cold temperatures can cause a slowing LCD response time " resulting in the "ghosting" affect visible on this fuel pump. User interfaces designed for use in extreme cold can make sure this problem is avoided.

The ability to produce user interface technology that can provide reliable performance in from -20°C to -40°C and from +70° to +85°C is new and comes as a direct result of a technological breakthrough. Previously LCDs that operated in extreme cold or extreme heat required bulky built-in heaters and coolers in order to ensure performance.

The latest generation of extreme condition LCDs utilize a special liquid-crystal formulation that eliminates the need for coolers and allows for the use of low-power, ultra thin heaters This has allowed for the creation of cost-effective custom LCD technologies that rival or beat off-the-shelf technologies costs while providing compatibility with a wider range of temperatures and enhanced visual performance.

Tip 2: Understand your visual display needs
Pin-pointing your exact visual display needs will also prove essential in designing a user-interface that can perform in extreme conditions. Be sure to address questions such as: Is it important that your display be available in color or monochromatic? Do you need full graphic or only a simple alphanumeric capability? What resolution image is needed for your application? How important is full daylight visibility?

The answers to these questions will help you select the best user interface technology for your application. There are many more visual display options available today than in the recent past. For example, it used to be the case that monochromatic LCDs were only available in alphanumeric with relatively poor contrast. The latest generation of displays provides full graphic capability with almost limitless customization including daylight visibility.

When combined with LED backlighting technology, a wide range of color options are available. Users can either opt for a monochromatic screen with any color of LED backlight, or select a negative image option with mono-colored pixels and a dark background.

Tip 3: Compare systems cost
Once you have a clear understanding of environmental considerations and visual display needs, you will be ready to compare the technology costs of various user interface technologies.

As the latest generation of extreme temperature LCD interfaces no longer require built-in coolers and can use low-power heaters, the cost of this technology has decreased. Custom LCD displays can now provide a 50 percent savings in technology costs compared to vacuum fluorescents.

Custom LCD solutions are growing in popularity as latest-generation technology allows design engineers to create technology that addresses the exact needs of their particular application at a lower price than was previously available for off-the-shelf technologies. If you opt for a custom solution, be sure to identify a supplier who can provide expert advice on how to integrate the interface technology into your larger system.

Tip 4: Dont overlook energy savings
When calculating costs, be sure to factor in all possible expenses beyond simple technologies expenses. For example, energy efficiency is an area where significant costs savings are possible. LCD technology can provide a 70- to 80-percent reduction in power requirements compared to alternative technologies such as vacuum fluorescent user interfaces.

Tip 5: Identify a supplier with broad experience
Extreme conditions bring with them a unique set of engineering challenges. It can be hugely helpful to find a technology supplier who can not only provide the user interface component but also professional insights as to how to integrate this component into larger systems. For example, an LCD supplier who can also provide LED backlight technology in a system designed for optimal performance in extreme heat or extreme cold.

With these five tips in mind, and thanks to recent technological advancements, design engineers can reach new heights in developing user interface solutions that provide cost-savings, superior reliability, and enhanced visual performance in even the most challenging of environments.

Author Bios:
Yasoob Ahmed is display technology manager and Brian Coates is market development manager at Lumex, a provider of LED and LCD technology. Both can be reached at engineering@lumex.com.