Recent developments in rugged, resistive touch panels improve instrument performance and the user experience.
In the industrial environment, touch panels, or touchscreens, facilitate operator input in a very simple, yet reliable, way. As touch input-based handheld and mobile devices enter more industrial applications – such as portable flow controls and handheld terminals for field testing – companies need to protect and extend their investment. A number of developments exist that optimize the life of the touch interface while improving instrument performance and the user experience.
The simple structure, durability and low cost of resistive touch panels typically make this technology the leading choice for industrial instrumentation. Recent technological advances, however, have made these touch panels even more durable for the industrial environment.
One new development is the Film-Film-Plastic resistive touch panel, which uses a polycarbonate, rather than a glass, plate. These all-plastic touch panels are 30-40% lighter than Film-Glass panels, making them ideal for mobile industrial terminals and computers. Because there is no glass layer, they are unbreakable from repeated stylus input and are much less likely to shatter or break if dropped or struck against another object. The plastic panels can also endure a wider operating temperature range than glass-based panels. Users can access the efficiency of touch-based instrumentation in applications that weren’t possible before.
For applications that must endure heavy or repeated stylus input, a “hard-tap” surface can be added to the Film-Film-Plastic touch panel to further increase durability and prevent damage. This 3H hard-coat cover film is layered over the panel’s top plastic film. This simple addition increases the panel’s input load by 50 percent and doubles its operational life. With a hard-tap surface, the device is better able to withstand a wide variety of pressure and point impact loads from different operators.
In the design phase, Film-Film-Plastic touch panels can be easily formed into custom shapes or to make the device’s structure more ergonomic. It’s also easy to print directly onto the plastic plate, so custom icon sheets or numeric key indicators can be developed to increase user friendliness and input accuracy, or to create shortcuts.
Another way to extend the life of a touch panel is by using Self-Wetting Adhesive Protector Sheets. These are inexpensive, polymer sheets with a 3H surface hardness. They are scratch and chemical resistant, yet they retain consistent, excellent, stylus registration while preserving the panel’s optical quality. Users can easily apply them in the field, reposition them if necessary, and remove them by hand, even after an extended time, without leaving any residue or creating static electricity.
These new methods, when used alone or together, optimize the performance of the device and the user’s experience with touch panel instruments in rugged industrial applications. They add elements of safety and durability, are reliable and cost effective to implement, and ultimately lower replacement costs of expensive equipment.
Bruce DeVisser is product marketing manager for Touch Input Devices at Fujitsu Components America in Sunnyvale, CA, USA. His career experience includes over 20 years in HMI analysis, design and implementation. He can be reached by mail at Fujitsu Components America, Inc., 250 E. Caribbean Dr., Sunnyvale, CA 94089; telephone 408-745-4928, or email at bdevisser@fcai.fujitsu.com. For more information on Fujitsu touch panels, go to http://us.fujitsu.com/touchpanels/.
