Touch Screens are a type of display screen that has a touch-sensitive transparent panel covering the
screen. Instead of using a pointing device such as a mouse or light pen, you can
use your finger to point directly to objects on the screen.
screens provide a natural interface for computer novices, they are unsatisfactory
for most applications because the finger is such a relatively large object. It
is impossible to point accurately to small areas of the screen. In addition, most
users find touch screens tiring to the arms after long use.
are typically found on larger displays, in phones with integrated PDA features.
Most are designed to work with either your finger or a special stylus. Tapping
a specific point on the display will activate the virtual button or feature displayed
at that location on the display.Some phones with this feature can also recognize
handwriting written on the screen using a stylus, as a way to quickly input lengthy
or complex information
touchscreen is an input device that allows users to operate a PC by simply touching
the display screen. Touch input is suitable for a wide variety of computing applications.
A touchscreen can be used with most PC systems as easily as other input devices
such as track balls or touch pads. Browse the links below to learn more about
touch input technology and how it can work for you.
A basic touchscreen has three main components: a touch sensor, a controller, and a software driver. The touchscreen is an input device, so it needs to be combined with a display and a PC or other device to make a complete touch input system.
1. Touch Sensor
A touch screen sensor is a clear glass panel with a touch responsive surface. The touch sensor/panel is placed over a display screen so that the responsive area of the panel covers the viewable area of the video screen. There are several different touch sensor technologies on the market today, each using a different method to detect touch input. The sensor generally has an electrical current or signal going through it and touching the screen causes a voltage or signal change. This voltage change is used to determine the location of the touch to the screen.
The controller is a small PC card that connects between the touch sensor and the PC. It takes information from the touch sensor and translates it into information that PC can understand. The controller is usually installed inside the monitor for integrated monitors or it is housed in a plastic case for external touch add-ons/overlays. The controller determines what type of interface/connection you will need on the PC. Integrated touch monitors will have an extra cable connection on the back for the touchscreen. Controllers are available that can connect to a Serial/COM port (PC) or to a USB port (PC or Macintosh). Specialized controllers are also available that work with DVD players and other devices.
3. Software Driver
The driver is a software update for the PC system that allows the touchscreen and computer to work together. It tells the computer's operating system how to interpret the touch event information that is sent from the controller. Most touch screen drivers today 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 allows the touchscreen to work with existing software and allows new applications to be developed without the need for touchscreen specific programming. Some equipment such as thin client terminals, DVD players, and specialized computer systems either do not use software drivers or they have their own built-in touch screen driver.
Touchscreens Add-ons and Integrated Touchscreen Monitors Touchscreen add-ons are touchscreen panels that hang over an existing computer monitor. Integrated touchscreen monitors are computer displays that have the touchscreen built-in. Both product types work in the same way, basically as an input device like a mouse or trackpad
Touch screens consist of a display component, typically a liquid crystal display (LCD) or CRT covered or surrounded with a transparent sensor device that allows the screen to detect the contact or proximity of an object. There is a wide variety of sensor devices. Some devices are not entirely transparent or create glare that makes the screen behind the device hard to see. The amount of pressure or types of contact needed to detect a touch varies from device to device. Devices also vary widely in accuracy (determining exactly where the touch occurred), durability (reliability with repeated use or in inclement circumstances), expected lifetime (time before failure of the device or parts of it), and response time (how long it takes the screen to detect a touch).