Display tech to watch this year: Multitouch catches fire

Computerworld - Touch-screen panels have been around for more than a decade, but it was the 2007 introduction of a multitouch screen in Apple's iPhone that galvanized the market. Now the business is going gangbusters -- as are the innovations that touch-screen manufacturers hope will build on Apple's success.

Multitouch technology has exploded into a $6 billion business for display manufacturers this year, with more than 200 vendors vying for a piece of the action -- and it's expected to grow to more than $13 billion by 2016, according to market research firm DisplaySearch. "It's already a huge market, and growing fast," says analyst Jennifer Colegrove.

Multitouch now dominates in smartphones, and with the introduction of the iPad in 2010, multitouch helped launch the market for tablet computers. The technology is now moving into everything from larger desktop PC displays to the in-flight entertainment systems found in the seatbacks of commercial airliners -- and beyond.

Editor's note: This is the first of a four-part series on red-hot display technologies to watch in 2011. Check back next week for another sizzling display technology.

A touch, not a press

Before the iPhone, most touch screens used pressure-sensitive, resistive touch panels, which required that the user physically press down on the screen. Resistive screens could track the position of just one finger at a time.

Apple chose a competing technology, projected capacitance, which responds to a light touch and can also sense a finger as it enters the electronic field above the touch surface -- a technique called proximity sensing. The touch panel sits on top of the display media (most commonly a liquid crystal display). Capacitive touch-sensing technology requires a person's finger (or a specially designed capacitive stylus) to disturb the electrical field; unlike resistive designs, it doesn't work with an ordinary stylus or other inanimate objects.

Projected capacitive screens use a glass touch surface that offers a higher level of transparency than the plastic layer used in resistive technology, resulting in brighter colors. The glass touch surface is also more durable, and capacitive technology is more forgiving of surface scratches.

Apple's major innovation with the original iPhone was figuring out how to track the actions of two simultaneous touches, which enabled the development of the iPhone's now-familiar gestures: swipe, rotate and pinch/expand. "It's really how the software is used that makes touch screens usable," says Bruce Gaunt, a mechanical engineer at Product Development Technologies, a product development firm that designs and integrates touch-screen technologies for manufacturers of cell phones and laptops. "That's what Apple does really, really well."

More recently, Samsung has had success integrating multitouch technology into active-matrix organic light-emitting diode (AMOLED) screens in devices such as its Galaxy S smartphone. Branded Super AMOLED, the technology places touch sensors directly on the screen itself rather than requiring a separate layer, which makes for a thinner display.

"Samsung is a pioneer in implementing touch in active-matrix OLED displays, and more are going to follow," says Vinita Jakhanwal, an analyst at market research firm iSuppli.

Proliferation -- and limitations

This year the smartphone market will reach a crossover point, with more than 50% of units including multitouch displays on projected capacitive or OLED touch screens, says Jakhanwal. Tablet computers are another fast-growing market for multitouch, as demonstrated by the iPad's success, not to mention the slew of new tablets announced at this year's Consumer Electronics Show.