How a Chinese company’s pressure sensors spell end of physical smartphone buttons

Physical buttons could be replaced by highly sensitive pressure sensors made by Shenzhen tech company NDT

The sensors can detect 1,000 levels of pressure and sit under the phone’s screen or body

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Haptic pressure sensors embedded in smartphones could do away with the need for physical buttons. A Chinese company founded by a former Motorola engineer is a leading developer of the technology. Photo: Ben Sin

Published: 8:00pm, 19 Nov 2019Updated: 8:28pm, 19 Nov 2019

A consistent trend in personal computing is the removal of moving hardware parts.

The computer mouse used to rely on an internal rubber ball to track movement; now it’s all done via lasers. Video game consoles and desktop computers once were turned on by a physical moving power switch; now it’s usually a capacitive touch panel. And it’s been more than a decade since Steve Jobs ushered in the modern era of smartphones that replaced a physical keyboard with a touch screen one.

For smartphones – the industry that now leads the way in computing innovation – next to go will be physical buttons.

The change began around 2016, when many Android phones moved to digital on-screen navigation buttons and Apple replaced the iPhone’s clickable circular home button with a tactile one on the iPhone 7. But those were relatively simple solutions that left user interaction the same – press an area to trigger an action.

The small black rectangles on the chip are the “resistors” that detect “deformations” from the surface they’re attached to. Photo: Ben Sin

A more advanced solution is beginning to roll out in newer handsets: any part of a phone can be pressed, and instead of just offering on/off functionality, these parts are pressure sensitive, essentially serving as analogue force sensors.