How Touchscreens Work
A touchscreen has 3 main components: a touch sensor, a controller, and a software driver. To make a complete touch input system, a touchscreen is combined with a display and a PC or other device.
1. Touchscreen Sensor
This is a glass plate having a touch responsive surface. The sensor is positioned over a display screen, so that the responsive area of the plate covers the maximum viewable area of the video screen. There are a number of touch sensor technologies available in the market today, each using a different approach to detect touch input. The sensor has an electric current or signal passing through it and touching the screen causes a change in the voltage or signal. This voltage or signal change is used to find out the location of the touch to the screen.
The controller used in a touchscreen is a small PC card that interconnects between the touch sensor and the PC. The controller takes data from the touch sensor and converts it into information that PC can understand. For integrated monitors, the controller is usually installed inside the monitor, or is placed in a plastic case for external touch add-ons/overlays. The controller is useful to determine what type of interface/connection you will need on the PC. Integrated touch monitors are provided with an extra cable connection on the back for the touchscreen. Controllers are available by connecting to a Serial/COM port (PC) or to a USB port (PC or Macintosh).
3. Software Driver
The driver is software for the PC system that permits the touchscreen and computer to work together. It tells the operating system of the computer how to interpret the touch event information that is sent from the controller. Today’s touchscreen drivers are a mouse-emulation type driver. This makes touching the screen the same as clicking your mouse at the same location on the screen. This permits the touchscreen to work with existing software and provide new applications to be developed without the need for touchscreen-specific programming. Some devices such as thin client terminals, DVD players, and specialized computer systems either do not use software drivers, or they have their own in-built drivers.
Uses of Touchscreens
Touchscreens are one of the simplest PC interfaces to use, making it the interface of choice for a large number of applications. The following are some of the uses of a touchscreen.
1. Public Information Displays
Tourism displays, trade show displays, information kiosks, and other electronic displays are used by large number of people who have little or no computing experience. The touchscreen interface is easier to use than other input devices, especially for novice users. It is useful to make your information more easily accessible by allowing users to navigate your presentation by simply touching the display screen.
2. Retail and Restaurant Systems
In the retail or restaurant environment, touchscreen systems are easy to use so employees can get work done faster, and also training time can be reduced for new employees. As input is present right on the screen, valuable counter space can be saved. Touchscreens can be used in order entry stations, cash registers, seating, reservation systems, and more.
3. Control and Automation Systems
Touchscreens are useful in systems ranging from industrial process control to home automation. Valuable workspace can be saved by integrating the input device with the display. In real-time, by simply touching the screen and with a graphical interface, operators can monitor and control complex operations.
4. Computer-based Training
The touchscreen interface is more user-friendly than other input devices, so overall training time for computer novices, and therefore training expense, can be reduced. It can also more useful to make learning more fun and interactive, which can lead to a more beneficial training experience for both students and educators.
5. Assistive Technology
The touchscreen interface is very useful for those having difficulty using other input devices such as a mouse or keyboard. When used with software such as on-screen keyboards or other assistive technology, they can help make computing resources more available to people who have difficulty using computers.