A touch screen or multi-touch display is the combination of an output and input device together with a mechanism for detecting touching. The touch screen is generally placed on top of an external data processing unit (IDM) or digital display. The screen is most often an LCD or an LED screen while the system is generally a smartphone, tablet, or laptop. While some modern touch screen technologies provide a wider color display, the most common use is for pointing devices such as a stylus or finger.

Touch screens operate through a number of physical processes including the detection of a finger or hand, movement of the finger to point at an item, signals from the device speaker and infrared light to the monitor and back to the touch screen itself. There are four basic layers in a touch screen. The first layer is the resistive surface acoustic wave. This wave is usually produced by the capacitance of the touch sensitive device or the conductive layer of the device, where it interacts with the surface. The second layer is the capacitance enhancement layer, which increases the electrical conductivity of the surface to make it a better conductor of electricity and to increase the signal strength so that the user may interact with the device using a stylus, finger or other types of touch-sensitive device.

The third layer is the semi-transmissive device media which allows some amount of transmission of the electric field from the finger or the other items that are used to manipulate the device. The fourth and final layer is the photoelectric layer that may include a thin layer of mercury trioxide, silver oxide or titanium dioxide that changes depending on the frequency of the transfer. The changes in the media allow the electric field to change the levels of charge for the different items that are used to manipulate the device. Since this change is only seen when the finger or whatever items are used activates them, it becomes impossible to conclude if the change is intentional or not. These changes in the resistivity and the media that are used also affect the power required to activate the electrically responsive device.

Another interesting phenomenon can be explained with respect to the power needed to reactivate the capacitive interface that is present on the touch screen of the device. On one hand, we can conclude that the power consumed by the finger that activates the device is the same as the power needed to deactivate the capacitive interface that is present on the device. Since the two processes involve the interaction of the finger with the screen, it is safe to conclude that the amount of power required to reactivate the device is equal to the amount of power required to deactivate the finger. What this means is that the total amount of energy required to power the device is less than the total energy required to power the device once the finger activates the device.

It is clear that the resistive layer does not play a major role in this process. What is still left is the part of the touch screen – the AMP layer – and the electric field that are induced between the two layers. What is observed is that the electrical field between the different layers appears to be changing depending on how the finger is placed on the input device. Thus, when the finger is placed on the home keypad, the induced electric field on the capacitance layer is different from the induced field on the resistive layer.

This difference in the electrical charge induced between the two layers can be explained with the idea that the capacitance is only significant for the time period when a finger is present on the touch screen. After some time, the absence of the finger on the input device can result in the absence of the capacitance. In such a situation, the amount of electrical charge required to stimulate the conductive layer changes. The change in the electrical charge is entirely dependent on the position of the finger on the touch screen. The higher the position of the finger, the higher the capacitance required to generate the desired response.

Touch screen protectors are also important in cases where the glass of the device or even the touchscreen is not touch sensitive. Touch screen protectors are specially designed to keep the finger safe from accidental touching. They help in preventing the damage caused by the frequent application of heat to the device. Heat causes the breakdown of the touch screen and also tends to change the colouration of the screen. Screen protectors reduce the effect of heat by preventing the device from damage.

Touch screen protectors for electronic devices are very important for the protection of the device as well as the efficiency of the device in terms of input. The devices are designed to be rugged and should be able to withstand a wide range of operating temperatures. They should also be resistant to chemicals that are used for cleaning the device and should be resistant to scratching. Since many of these devices are used at work places, they should be able to withstand pressure while in use.