recent advances in touch screen technology

Touchscreens have been available since the days of cathode-ray tubes, but the technology didn’t really catch on with consumers until mobile phone makers adopted it to solve the tiny-button problem. Now touchscreen smartphones and tablets collectively constitute the fastest-growing electronics market segment.
According to DisplaySearch , shipments of touchscreen tablets are forecast to reach 60 million units in 2011 and could top 260 million units by 2016. Add to that the more than 400 million mobile phone touchscreens predicted by IHS iSuppli Corp. (El Segundo, Calif.), and the total market could top $10 billion this year (see sidebar, last page).
“Touchscreens have been around for a long time, but they were only popular in business and industrial settings, such as food service, airport kiosks and industrial keypads,” said Rhoda Alexander, director of monitor research at IHS iSuppli. “The real transition for consumers … was when Apple moved into smartphones and then tablets. Before then, consumer touchscreens didn’t work very well, because they had to operate a standard OS. But with the move to smartphones and tablets, operating systems like iOS have enabled a very touch-friendly user interface.”
Google’s Android OS—the first major competitor to Apple’s iOS—-did not support multitouch at introduction, but the latest incarnation accommodates a wide array of multitouch gestures. Some of them—including spin, thrust and slice—are unique to Android; all will work identically on any Android smartphone or touchscreen tablet. The BlackBerry Tablet OS and Windows Phone OS have similarly become touch-enabled.
“Handset makers used to give us a long list of obstacles to adopting touchscreens, but when Apple introduced the iPhone all those obstacles suddenly seemed surmountable,” said Andrew Hsu, technology strategist at Synaptics Inc.
Synaptics began as an evangelist for the benefits of touchpads as a substitute for a PC mouse but has since reinvented itself as a touchscreen controller supplier for mobile handsets. It claims a number of major design wins, including one in Google’s Nexus One smartphone.
Just a handful of contrary trends threaten the touchscreen industry. Foremost are competing technologies that deliver a similar user experience without the expensive touchscreen hardware, such as the 3-D gesture recognition made possible by Microsoft’s Kinect gaming interface, which uses cameras and pattern recognition to sidestep the need for the sensors required by handheld controllers. Kinect-like 3-D gesture recognition, using infrared rangefinder technology Microsoft acquired from Canesta, is being downsized for Windows phones and tablets. Armed with a touch-enabled version of Windows that works across all device sizes—from its own 40-inch Surface to its licensed touchscreen tablets and smartphones—Microsoft could redefine the touchscreen landscape.
Meanwhile, all the LCD makers are retooling their manufacturing lines to incorporate touchscreen sensors directly into their displays, a move that would eliminate the need for today’s OEM add-ons. Samsung and Nokia, for instance, have already integrated touchscreens into organic LED displays for their respective Galaxy S and N8 smartphones.
Alternative materials for integrated touchscreen sensors are also on the horizon, including Cambrios Technologies’ ClearOhm transparent conductors, using silver nanowires; C3Nano’s carbon nanotube films; 3M’s copper-mesh films; repurposed polyethylenedioxythiophene conductive polymers; and epitaxial graphene films from a variety of vendors. All aim to slash the cost of touch sensors over the increasingly rare indium tin oxide (ITO) used for touch sensors today.