Buttons that pop out over touch displays
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Tactus Technology
Touch keyboards are almost impossible to navigate blind, but not our physical keyboards. The reason is the tactile feedback our fingers get from the raised qwerty keys. Tactus Technology, a California-based company, has been working on buttons that physically morph out and then flatten back from a thin panel that can be placed over touchscreens. The company traces back to research work on drug delivery systems through the skin, using microfluidics, a technology applied in inkjet printers and LCD screens.
Backstory
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How It Works
Let's back out a bit. Microfluidics is fluid physics at extremely small scales - below a millionth of a litre. Just as the integrated circuit put discrete components onto a chip, automation of fluid micro-channel networks could allow a biology or chemistry lab on a chip. This is like plumbing - with pumps and valves that allow an assembly line for fluid manipulation - at a miniaturised scale.
But fluid physics changes dramatically as the scale changes, unlike microelectronics where transistors have become smaller and smaller, to the point of single-electron transistors with the same physics, as one review article from Caltech researchers in 2005 points out. Still, as a system, what's important is that the flow of the fluid be controlled like it's important to control the flow of electrons and the current in logic circuits.
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In the Tactus system, an actuator on the side controls the microfluidic flow through a voltage differential. Once the fluid is flowing, you can have pressure being applied at specific points on a deformable surface. That surface can be manipulated to deform into buttons and revert back to the flat surface once the fluid pressure is off. Tactus seems to have eventually got this down pat - it takes a second or so for the buttons to pop out and to merge into the surface.
Breaking Out
Tactus received $6 million in funding from Thomvest Ventures in late 2011. It has been a regular at the consumer electronics show to mostly positive reviews, and has reportedly showcased a prototype overlay for the iPad mini. Last year, the company reportedly worked on prototypes with Synaptics, the ubiquitous touchpad company. This year, it has announced a manufacturing partnership with Taiwan-based manufacturer Wistron, and Japan-based electronics supplier Ryoyo.
Platform Pitch
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Once you have a morphable surface, it is possible to have modes where different buttons pop out, say, for gaming and on-the-go-music. Tactus seems to have filed a patent for the programming logic of such a system.
Still, making the buttons grippy enough and having a clear surface panel at the same time may not be so easy.
To show why tactile is better, the company refers to a 2002 study done by Sony researchers on its website that shows speeds of scrolling for tactile feedback. The small but widely cited study found that users preferred the tactile response not so much for functional reasons, but because of better user experience. That might be key for Tactus.