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A touchscreen or touch screen is a computer screen that can be used by touching it with a finger or a stylus pen, instead of using a mouse and keyboard. Touchscreens are used in personal digital assistants (PDAs), tablet computers, smartphones and other devices.

Some touchscreens are capable of pressure-sensitive input, in which thicker lines are made on the screen when the user pushes harder down on the digital pen.

Interactive whiteboards, which can be found in many schools, use a simple form of touch technology.

JazzMutant Lemur

History[change | change source]

In 1965, E.A Johnson of England’s Royal Radar Establishment, invented[1] the first touchscreen that was used in the U.K for air traffic control up until around 1995. The first resistive touch screen was invented by G. Samuel Hurst in 1975, and produced in 1982. Back in 1970, Hurst and nine friends discovered that a touchscreen on a computer monitor made for an excellent method of interaction. Pressure on the cover sheet allowed voltage to flow between the X wires and the Y wires, which could be measured to indicate coordinates. This discovery helped found what we today refer to as resistive touch technology (because it responds purely to pressure rather than electrical conductivity, working with both a stylus and a finger).

Much later in 2005, three friends from France created a multi touch screen capable of tracking any numbers of fingers. By 2005, their company named JazzMutant released the Lemur, a music controller with a multi touch screen interface. This new technology helped influenced the TactaPad also made in 2005. Two years later, the iPhone, which is the first successful smartphone, was released. [2][3]

Usage[change | change source]

Touch screen is widely used on Automatic Teller Machines, retail point-of-sale terminals, car navigation systems, medical monitors and industrial control panels, the touch screen became wildly popular on handhelds after Apple introduced the iPhone in 2007[4]. The touchscreen is built into kiosks that are used for informations systems in cities and museums. Kiosks use simple point and click interaction. Phones, computers, tablets, smart boards, computer printers, television and most recently, watches, also include touch screen systems.

How It’s Built[change | change source]

Different kinds of touchscreen work in different ways. Some can sense only one finger at a time and get extremely confused if you try to press in two places at once. Others can easily detect and distinguish more than one key press at once. These are some of the main technologies:

  • Resistive touch screen has a layer of conducting polyester plastic where when you press on it, you force the polyester to touch the glass and complete a circuit. A chip inside the screen identifies the coordinates of the place you touched.
  • Capacitive touch screens are made of multiple layers of glass. The inner and outer layers of glass conduct electricity. The screen behaves like two electrical conductors separated by an insulator—in other words, a capacitor. Capacitive screens can be touched in more than one place at once. However, it won’t work if you touch them with a plastic stylus because the plastic acts as an insulator.
Capacitive touchscreen diagram

References[change | change source]