What is one of the most commonly used technologies we see and yet fail to admire in this modern age of Digitalisation? In my opinion its the Touch Screen.
Touch Screens have replaced buttons from our day to day life, say from smartphones to even sophisticated industrial pieces of machinery. Its so much fun and easy to access kinds of stuff just within a few touches. This technology has brought out an entire revolution in its own. The appreciating fact is that it was accepted, modified and developed to current form in just a couple of decades which is very rare in the field of technological development.
So, its time to take a dive into the history of the technology that you are most probably using right now to view this article, i.e. Touch Screen
Credits – ARS Technica
1960’s – Capacitive Touch Screen Technology
The foundation of the touch screens we know today starts in 1965. That’s when E.A. Johnson discovered the benefits of touchscreen technology and invented the first finger-driven touchscreen.
He published his creation in an article called ‘Touch display – a novel input/output device for computers‘. The article featured a diagram as well, describing a technology that we still use today in ATM and kiosk applications. Capacitive touchscreen technology.
1970’s – Resistive Touch Screen Technology
The resistive touchscreen was realized 5 years later in 1970, by Dr. G. Samuel Hurst. Resistive touchscreen technology quickly outshone its predecessor. Dr. Hurst actually invented this type of touchscreen technology by accident during a scientific experiment.
He later spent some time perfecting the touch screen and realized the benefits of touch screens when he placed it over a computer monitor. Today resistive touchscreens are the cheapest of its kind and widely used in restaurants and factories around the world. Taking advantage of its durability.
1980’s – First Commercial Use
In the early 1980’s touch screens were used more frequently and in more diverse applications. Hewlett-Packard commercialized touch screens by launching the HP-150. The first touch computer.
The University of Toronto then took a great step in the development of touchscreen technology. They discovered multi-touch. In 1982 they invented the first human-controlled multi-touch device. A touchscreen that could detect multiple touch points.
The advantages and benefits of multi-touch screens were endless. Multi-touch screens allowed users to manipulate objects with their fingers with excellent response times.The discovery of multi-touch screen technology turned out to be of great importance to the smartphones and tablets we use today.
1990’s – First Touch Phone
In 1993 IBM and BellSouth came up with the first phone with a touchscreen interface – the Simon Personal Computer. Apple followed suit with their own version of touchscreen telephony with the Newton touch sensitive PDA. Basically, the first smartphones ever are known.
2000’s – Other Touch Screen Technologies
In the 2000’s multiple companies started to really appreciate touchscreen technology. Using E.A. Johnsons original capacitive touchscreen technology, other touch technologies like Surface Acoustic Wave, Infra Red, and Projected Capacitive touch screens were invented. All carrying their own benefits and limitations.
How does a TouchScreen Works?
There are three basic systems that are used to recognize a person’s touch:
- Surface acoustic wave
The resistive system consists of a normal glass panel that is covered with a conductive and a resistive metallic layer. These two layers are held apart by spacers, and a scratch-resistant layer is placed on top of the whole setup. An electrical current runs through the two layers while the monitor is operational. When a user touches the screen, the two layers make contact in that exact spot. The change in the electrical field is noted and the coordinates of the point of contact are calculated by the device. Once the coordinates are known, a special driver translates the touch into something that the operating system can understand, much as a computer mouse driver translates a mouse’s movements into a click or a drag.
In the capacitive system, a layer that stores electrical charge is placed on the glass panel of the monitor. When a user touches the monitor with his or her finger, some of the charges are transferred to the user, so the charge on the capacitive layer decreases. This decrease is measured in circuits located at each corner of the monitor. The device calculates, from the relative differences in charge at each corner, exactly where the touch event took place and then relays that information to the touch-screen driver software. One advantage that the capacitive system has over the resistive system is that it transmits almost 90 percent of the light from the monitor, whereas the resistive system only transmits about 75 percent. This gives the capacitive system a much clearer picture than the resistive system.
On the monitor of a surface acoustic wave system, two transducers (one receiving and one sending) are placed along the x- and y-axes of the touchscreen’s glass plate. Also placed on the glass are reflectors — they reflect an electrical signal sent from one transducer to the other. The receiving transducer is able to tell if the wave has been disturbed by a touch event at any instant, and can locate it accordingly. The wave setup has no metallic layers on the screen, allowing for 100-percent light throughput and perfect image clarity. This makes the surface acoustic wave system best for displaying detailed graphics (both other systems have significant degradation in clarity).
Video Courtesy – ” BBC Earth labs “