A touch screen or a capacitive touch screen is an assembly of an input and output unit. The touch screen is generally placed on top of a multi-touch information processing device with a substrate that is touched or brushed. While the device is typically a touch screen tablet, laptop, or smartphone, the display is most commonly LCD or LED screen. Touch screens can also be integrated with resistive, capacitive, infrared, or acoustic wave technology.
The capacitive type of touch screen is based on electrochemical interactions between the input device and the display screen. These types of screens work by having an electrical current applied to an area of the display. This current is produced by a piezoelectric device that measures the changes in capacitance as the user gently touches the display. As the finger is moved over the screen, the amount of current flowing through the device causes a change in capacitance.
A capacitive touch screen requires two components for operation. The first component is called the controller. This component receives analog input signals from the user’s fingers and modifies them before displaying the image on the display. The second component is called the sensor. This component is located between the controller and the display screen and it picks up signals from the finger and analyzes them to determine what actions the user wants to make.
Capacitive touch screens use a mechanical action to sense what the finger is touching. A resistive touch screen operates the same way but uses an electrical charge to change the capacitance level. A capacitive stylus is used with this type of touch screen. The stylus is a small touch screen computer that fits in the user’s hand and interacts with the computer. As the stylus makes contact with the screen, a change in capacitance occurs which causes an electric signal to be produced.
Capacitive touch screens are often used in smartphone devices, laptop computers, tablet PCs, gaming devices and other portable devices that run on touch screens. They are especially popular in devices that are used by children, such as toy phones and e-readers. It is also common for larger devices, such as televisions and monitors to include touch screens. This allows the television to scroll and flip through channels, and the monitor to react to touch or movement from your finger or other devices that are present in proximity to the television.
There are three basic technologies that make up this type of input device. First, there is the resistive touch screen. A thin sheet of plastic or metal is charged to provide a passive touch on the screen. When you brush your finger against the screen, a signal is emitted, causing the display to change. These devices must have active components in order to detect the finger’s motion. Some of these resistive touch screen technology is referred to as capacitive, because it works based on physical pressure, rather than relying on an invisible signals like touch-screens and fingerprints.
Second is the capacitive touch controller. The simplest capacitive controller is made up of a ring of conductors that sense the finger’s touch. This type of device is often used in phones and other mobile devices where there are only a few buttons or touchscreens, because it is not possible to include extra buttons or input devices. Capacitive technology may require the user to point their finger directly at the screen or to make an effort to move the finger in a certain way to get a response.
Thirdly, there is the surface acoustic wave controller. A wide array of devices that use this form of input device are televisions, DVD players, home stereos, game consoles, and computer keyboards. This type of controller has to use a collection of thin layers of transducers that catch the electronic signals emitted by the user’s finger. This type of controller can detect subtle changes in the frequency of the signal being produced, which then causes the displayed image to change. However, it has been found that the most accurate results are obtained when the output and input devices are set to work in correlation. In this case, the output and input are set to respond to the same waveform, which then enables the display to accurately capture the movement of the finger and form the image.