It may be as ubiquitous today as lanyards at ISE, but for what is a relatively new innovation, interactive display technology actually took a while to become fully established: over 50 years. And, interestingly enough, although capacitance was first out of the blocks, optical camera systems soon followed.
In articles published in 1965 (Touch display — a novel input/output device for computers) and 1967, Eric Johnson of Britain’s Royal Radar Establishment, described his work on capacitive touchscreens.
In the early 1970s, Frank Beck and Bent Stumpe, engineers from CERN, the European Organization for Nuclear Research, developed a transparent touchscreen (the first capacitance display), said to be based on Stumpe's work at a television factory in the early 1960s. Around the same time (1972), a group at the University of Illinois filed for a patent for a single-touch optical touchscreen – a standard part of the Magnavox Plato IV Student Terminal. Frank Beck further developed his ’72 work for the control room of CERN’s accelerator SPS (Super Proton Synchrotron) Particle Accelerator in 1977.
In 1982, the University of Toronto's Input Research Group developed the first human-input multi-touch system, using a frosted-glass panel with a camera placed behind the glass. Then, in ‘85, the same group developed a multi-touch tablet using capacitance rather than the (at the time) bulky camera-based optical sensing systems.
Jump forward six years to 1991, and Pierre Wellner at the University of Cambridge wrote about his multi-touch Digital Desk supporting multi-finger and pinching motions in a published white paper. Sound familiar? Apple certainly liked the sound of it!
In 2001 Microsoft got involved, continuing the development of surface capacitance, and the company eventually created what was to be initially called its SUR 40 Surface table-top platform, subsequently renamed PixelSense in 2012 and more recently Surface Hub.
Just like other types of touch technology, capacitive uses a form of disruption to create a change of state when a display is touched. The control system acknowledges the touch, identifies its exact location and then translates it into a precise instruction to the computer software.
But regular capacitance was soon superseded by projected capacitance, and this itself has now been taken further with its latest advancement, true-bonded capacitive touch. Used both by Microsoft for Surface Hub and on CleverTouch’s large format displays, true-bonded capacitive touch virtually eliminates the air gap between screen layers. This allows large format screens to become exceptionally responsive to touch, in line with what people are accustomed to on their smartphones and tablets.
But despite this advancement, 3M (among others) continues to favour projected capacitance for now, and there are other non-capacitance technologies that remain popular – including optical systems.
Flatfrog’s InGlass Touch system injects light into any transparent medium, extracting it at the opposite side. An object touching the surface causes a disturbance and is detected at the receiver end. Another optical positioning system is Baanto’s ShadowSense. It uses high performance sensors to provide increased stability and accuracy.
Other less popular touch display technologies include resistive, acoustic pulse recognition, surface acoustic wave, force sensing, embedded touch, dispersive signal technology and infrared grid.
The burgeoning adoption of touchscreens across a variety of sectors is set to push the global display market past $20 billion by 2024, according to Global Market Insights Inc. And it’s perhaps no great surprise that much of this growth is in the retail sector where high street retailers are using touchscreens to enhance customer interaction.
From touch-enabled kiosks to interactive windows and walls, bricks and mortar retailers are relying on touch displays to encourage consumers in, even making purchases on in-store displays where appropriate.
The fast-moving pace of retail dictates that interactive tech won’t stand still, even if it wanted to. Today’s consumers expect fast response times and glitch-free touch, even if they are yet to encounter touch on the high street. Their smartphones and tablets initially set the bar, and anyone who has experienced today’s multi-touch marvels in action at museums and product launches won’t be undersold on the high street when it comes to interactive touch!