A touch screen or capacitive touch screen is a combination of an input and output interface device. The touch screen consists of a display screen, a finger pad, and a haptic feedback device such as a capacitive sensing unit. The touch screen is usually layered over an image of a data processing system. While the system is typically a mobile phone, tablet, or laptop the display is most often LCD LED or AMOLED display. Capacitive touch screens provide the user with a tactile feedback that is often more accurate than a resistive touch screen.

Capacitive touch screens use the physical action of your fingers to detect the touch in an interactive virtual environment. Your finger provides the electric charge to the capacitive unit which then converts the electrical charge to mechanical force to transfer from the finger to the screen. Resistive touch screen use pressure to detect the touch. The mechanical force is from the touch itself and is transferred to the screen via an electric charge from the touching finger. If you are trying to press a particular key on a computer keyboard, it may be necessary to move your finger in a circular motion in order to register a touch on the keypad.

One of the advantages of using touch screen technology is the image clarity. When you use a capacitive touch screen, the image clarity is comparable or better than what you get from a resistive or organic based screen. With a resistive screen the image is blurred at the edges and corners of the touch sensitive area. This makes the user’s finger difficult to see and is the main disadvantage to using this type of screen. Some resistive screens also have a red tint to them when the touch reaches the edges.

Capacitive touch screens also have disadvantages and they include the slow response time when the user presses the button, the low power consumption, the increased finger noise, and the possibility of losing the data if the finger gets stuck between the screen and the surface of the computer monitor. This type of screen has a short response time, which means the time taken to register a finger touch is very fast. Because of the slow response time it can take up to 7 seconds for the computer to register a finger touch. This can result in a slow response time and reduced image clarity of moving images on the screen.

The other two types are the polar opposite of each other. The first one is a resistive touch screen where the energy is used to push a charge from a thin wafer of indium tin oxide (ITO) on to the surface of the sensor. The second one is a capacitive one where the electrical current is used to push a charge from the surface of the sensor. The polar opposite of the resistive touch screen sensor is the acoustic wave sensor. This uses an acoustic wave of light which passes across the sensor. When this pressure wave reaches the surface of the touch screen then it registers that touch.

Although the touch screen technology is very convenient and easy to use, it has certain disadvantages too. One of the biggest disadvantages of using touch screen technology is that if a finger accidentally slips into the gap between the touch-sensitive layer and the display then the display will not function properly. It will either go off or perform erratically. And because of the rapid changes in the temperature of the surrounding air the finger may also get stuck between the sensitive display layer and the touch screen itself.

Some other disadvantages of using touch screens include eye strain and fatigue, and reduced accuracy as far as inputting numbers. And because finger movement is required the accuracy of the input is also reduced. This type of input device was used in calculators, pointing devices, and electronic maps but was later replaced with touch screens in many electronic devices like smartphones, tablets, cameras and monitors. Another disadvantage of this type of input device is that fingers are more likely to slip out of the holes on tablet computers. This makes them hard to use for some people.

However, although touch screen mobile phones have made it a lot easier to operate these devices, their disadvantages outweigh their advantages. The stylus is one way of overcoming their drawbacks. Most touchscreen mobile phones have no stylus slots because manufacturers do not make them as standard, and most other manufacturers require users to use stylus pens.