History of Computers - Touchscreen
By Ben Lee
The touchscreen is a pressure sensitive surface that can be used as an alternative to the mouse for interacting with the graphical user interface. Touchscreen technology is widely used in laptops, smartphones, and GPS systems.
Overview
The touch screen was first created in 1965 for use in air traffic control by E.A. Johnson.[1] but soon found its way into computers as a mouse substitute. Opaque touch pads like the one Johnson created are currently used mostly in laptops. One of the biggest advances in touch technology came in 1974 when Sam Hurst created the first transparent touch screen.[2] Hurst's see-through touchscreen opened a new realm of possibilities for applications of touchscreens on the actual display of a device. Examples of clear touch screens can be found on smartphones and GPS systems. One of the many ways that a touch screen works is by completing an electrical current with our own bodies. The surface of a touch screen is covered with capacitors. A capacitor, in this case, is composed of two conductive electrodes separated by an insulating gap. When our finger touches the screen, a capacitative contact is formed, and an ac current generated within the device also induces a similar current within humans, which spans the insulated gap and completes the current [3].
Significance
Touch technology has removed the need for a mouse, especially convenient with laptops. Also, touch screens have removed the need for almost all buttons on smartphones allowing for devices with larger screens while still remaining compact. Touch technology is easy to use and with new multi-touch technology recently emerging, more complex manipulations of the display such as zooming in or out and scrolling with only a swipe of a finger is becoming possible.
References
- ↑ Johnson, E.A. (1965). "Touch Display - A novel input/output device for computers". Electronics Letters 1 (8): 219–220.
- ↑ http://inventors.about.com/od/tstartinventions/a/Touch-Screen.htm
- ↑ http://engineering.mit.edu/ask/how-do-touch-sensitive-screens-work
