Touch-Screen Buttons with No Touch Screen

Azoteq, a South African fabless chip company exhibiting in the Quinn Pacific booth, is showing a very clever application of capacitive proximity-sensing. In the photo below, the buttons across the bottom of the screen would normally be implemented via a touch-screen; actually they’re implemented by sensing pads in the opaque bezel below the screen. The sensitivity and signal-to-noise ratio of the Azoteq proximity-sensing chip are so high that touching the on-screen buttons is indistinguishable from touching real touch-screen buttons, even though the actual sensors are more than an inch away.



















(Photo by Author)

This allows virtual touch-screen functionality to be implemented in devices such as printers, copiers, ATMs, VoIP phones, and point-of-sale devices at extremely low cost – because there’s no touch screen! The exact shape of the proximity-sensing field can be controlled so that only the button shapes are active; touching above, below or between the buttons has no effect. The proximity-sensing chip can also be used to wake up the device, thereby reducing standby power consumption. This is only one specific application of Azoteq’s proximity-sensing and user-interface technology; contact Azoteq (or Quinn Pacific, which is offering Azoteq’s patent portfolio for sale) for more information. -- Geoff Walker, Walker Mobile