Rugged displays and touchscreens provide interaction with users in environments ranging from tanks and fighter jets to kiosks and industrial control systems. No one system fits all needs, and designers have a wide range of choices that includes wireless solutions.
Very rugged environments might utilize a system’s approach like the Parvus DuraVIS 4310 (Fig. 1). This system has a 6.5-in. thin-film transistor (TFT) LCD with LED backlighting, an acrylic protective window, and MIL-C-14806-compliant anti-reflective coating. It’s ITO-coated (indium tin oxide) for glare and electromagnetic interference (EMI) control. Also, it boasts a 1.5-GHz Intel Core2 Duo Processor and associated hardware. It tends to be at the extreme end of rugged solutions.
Stealth Computer’s line of panel-mount LCDs (Fig. 2) represents displays that need to be more durable than conventional monitors and are often mounted in racks or other fixed locations. Like the DuraVIS line, variations on panel-mount displays include all-in-one solutions as well.
E Ink Is not Just For E-Readers
LCDs and plasma displays are the most common these days, often combined with touchscreen interfaces of varying flavors. Yet these screens often fall short in bright sunlight. E Ink’s greyscale displays perform exceptionally well in bright light because they are reflective. They are also low-power and popular in e-reader applications such as Amazon’s Kindle.
E Ink’s color display (Fig. 3) removes another advantage of LCDs and plasma displays. The color display is implemented using a filter over a standard greyscale display, so it is also limited in the same fashion when it comes to screen refresh time. The E Ink displays aren’t suitable for video streaming, but slow animation such as a flashing error announcement is possible. Wristwatches are available using this technology too.
The low-power aspect has other advantages. A small capacitor often has enough power to run a micro and the display during a power-down sequence, allowing the display to be changed. The E Ink displays are bistable, so this last change would be retained.
The E Ink displays are also flexible. Flexible LCD displays were unveiled last year but they are not readily available yet. Another alternative would be small projection systems like those based on Texas Instruments’ DLP technology. These pico projectors also could be used in novel ways.
Mobile Devices As Displays
Moving from a fixed to a portable display is sometimes an option that is becoming less expensive with the host of tablets on the market. The compact Archos 43 Internet Tablet (Fig. 4) is the same size (4.3-in. screen) as a smart phone but priced significantly less. Its wireless support would allow it to control any number of applications remotely. Likewise, the application running on the Archos tablet could also run on an Android smart phone.
For example, a tablet could be used to replace a conventional display in a printing environment, such as Hewlett-Packard’s Photosmart eStation C510a (Fig. 5). This printer features a wireless Android tablet like the Archos 43 but with a 7-in. screen.
Rugged tablets are also available, but this just shows how embedded display options are changing. So don’t order that plain LCD just yet.