Touch screens have been with us since the early 1970's but it has only been in the last few years that the technology has expanded into personal applications as well as business.
Traditionally touchscreen displays were expensive and only to be found in industrial applications but recent advances and falling cost of technology has meant that the touch screen display is now in everything from the mobile phone and pocket computer to ATM machines and information points.
Touchscreens work in one of a number of ways from using infrared to detect the heat of a finger to the more accurate resistive and capacitive touch screens that use an electrical field.
Touchscreens have an obvious advantage over conventional monitors in that using a graphical user interface (GUI) and touch screen means that the display can act as both an input and output device so there is no need for a separate keyboard and mouse and their associated wires.
In selecting a touch screen display several questions need to be asked – what tasks will the display be used for, how clear the monitor need to be, what environment will it be placed in and how responsive does it need to be?
In an industrial environment where the display may have to end contaminants such as grease, dirt and dust or suffer the risk of getting wet then a sealed capacitive touchscreen would be the best option. These are very durable and rugged and many of are manufactured for water and dust resistance (IP56 and IP65).
When more clarity is required from the screen (most touch screens have less lighting than conventional monitors) such as for surgical or medical use then surface wave panel-based touch screen is the better option. These use ultrasound to identify when they are touched and can easily be damaged but they offer better clarity and optical accuracy than other systems.
If a touchscreen display is to be left in a public area, unattended or outside then the simplest form of touch screen, the strain gauge, where the screen is spring mounted on the four corners and the movement is measured when the screen is touched, is by far the most durable touch screen display. While they are not as responsive as other types of touch screen they are often used when there is a risk of vandalism.