Every gadget worth its salt seems to be employing the use of a touchscreen interface at the moment, so we thought we’d take a look at the technology behind it, the devices that are using it and also what the future might hold.
A BRIEF HISTORY
Touchscreens have exploded into the public arena in the last couple of years, becoming the interface of choice for a variety of applications but, they have actually been around for a little more than you might think, albeit in a slightly different form.
Samuel Hurst is largely credited with the first “touch tablet” device (named the Elograph) in 1971 and then the first touch screen in 1974, however, forms of touch technology were being used much before then – music technology innovator Hugh LeCaine was developing instruments with touch sensitive technology way back in the ’50’s, for example, pre-dating PCs by some distance, and companies such as IBM were also developing touchscreens in the late 60’s.
Early touch sensitive devices were, and still are, used in a wide variety of roles as diverse as point-of-sale terminals in shops, self-service kiosks and PDA devices, amongst other things.
In terms of computing, it is widely regarded that the first system to implement touch screen technology was the PLATO IV computer assisted education system, which was launched in 1972 and also was the first flat panel plasma display. Interestingly, the PLATO IV was also used as a terminal for connecting musical synthesizers to provide up to 4 different synthesized voices – once again, music was right at the forefront of technology.
PLATO IV is undoubtedly the fore-runner in computer-based touchscreen technology which has led us to today’s manufacturers offering the mainstream such wonders as touch screen desktop PCs, such as the Asus Eee Top, HP’s TouchSmart PC range to the new craze of the moment, tablet PCs, such as the Apple iPad.
Modern, multi-touch screens have also been in development for a surprising amount of time – Apple certainly took notice way back in 1982, when the University of Toronto came up with the first pressure-sensitive, multi-touch inputting device that would eventually lead to Apple trade-marking the term “multi-touch” and bringing the iPhone and iPod Touch to the mainstream market.
However, the direct descendant of the iPhone was actually the world’s first smartphone. Developed by IBM, “Simon” was born in 1992 and was the first mobile handset to offer customers a completely button-free, touchscreen based experience in which you could use either your fingers or a stylus to input data and featured a full QWERTY display, e-mail facilities, a calendar, games, fax capabilities and a notepad function.
Far ahead of its time, Simon failed to capture the imagination of the general public, but really paved the way for things to come.
TYPES OF TOUCHSCREEN
There a huge range of different touchscreen technologies – and many more being developed, as we’ll go into later – but for the purpose of this article we’ll concentrate on the 3 main types of touchscreen currently being used for the kind of devices you will see on the mainstream market.
Resistive touchscreens are made up of 2 electrically conductive layers and respond to pressure being exerted by an object by those layers coming into contact with each other, which produces the electrical current that is recognised by the operating system and translated by the processor as executable data. Resistive touchscreens were popular in the first smartphones – which were often accompanied with some form of stylus for pressing down hard – and offer a cheaper alternative to other touchscreen technologies, although are generally less colourful or sharp and can be damaged by sharp objects.
Resistive touchscreens can be found on a multitude of devices, including mobile phones such as the HTC Tattoo ,the LG KC910 Renoir or the Samsung Omnia and PCs such as the Asus Eee PC 901 or the Archos 9 PC Tablet. It’s worth pointing out that the majority of tablet-based devices released up to now currently use resistive touchscreens.
Capacitive screens are designed with an insulating material (glass, for example) which is coated in a transparent conductor which, when touched, combines with the human body’s own conductive qualities to produce a charge. This resultant change in “capacitance” (or electrical charge) is then processed in various ways, dependent on the technology used, which varies from device to device. Capacitive touchscreens are generally regarded as “better” than resistive, as they are more adaptable and far brighter.
Capacitive touchscreens are dominating the current gadget market, with devices including the iPhone, iPod Touch, Nexus One and the latest Blackberry range all featuring, as well as laptops such as the HP tx2.
SURFACE ACOUSTIC WAVE (SAW):
SAW touchscreens use ultrasonic waves that pass over the panel surface and are interrupted by touch, with a portion of the wave being absorbed. This is then interpreted by the internal system and translated into an executable action. SAW touchscreens are regarded by many as “the future” of touchscreens, but are currently hampered by being extremely sensitive – the panels themselves are easily damaged and contaminated by external elements, such as the weather.
Because of these present limitations, it’s fairly obvious that SAW touchscreens are not suitable for mobile or portable devices, however companies such as Planar and NEC have released SAW touchscreen monitors for home use.
It’s not just mobile phones, computers and mp3 players that use touchscreens. Nintendo introduced a touchscreen to their handheld console, the Nintendo DS, way ahead of the game, whilst the current craze for e-Book readers has led to most of the big players installing touchscreen functionality – check out the Sony PRS-600 or the BeBook Neo for examples.
Touchscreens are also highly visible in cars – with GPS systems‘ booming popularity being a major factor. There’s also a growing demand for all-in-one systems, with the JVC KW-NX7000 and the Alpine IVA W200 good examples of in-dash multi-media touchscreen devices.
Nobody can predict what will happen in the future with any certainty and there are different technologies emerging daily, but there have been 2 recent developments that have caught the eye could point the way with regards to touchscreens.
Firstly, there’s Peratech; a British company who have designed and developed a touchscreen using quantum physics that recognises how hard you are pressing, which could lead to a type of “3-D interface”, allowing you to access menus arranged in stacks – the harder you press down, the deeper you go into the stack – as well as scrolling and swiping.
Secondly, perhaps there is no future for touchscreens at all? Maybe we won’t need to touch anything. If you’ve seen Minority Report, you may will recognize some of the following, quite mind-blowing footage from tech company geniuses Oblong Industries, which blew away the crowd at this years TED event…………………and there’s not much more that we can add…