TFT touch screen

TFT touch screen is in simple terms called the touch screen monitor. Its price has decreased in recent years causing them to become more popular in mobile technology. There are 3 basic systems that recognize touch as the commanding source. These systems are resistive, capacitive and surface acoustic wave.

A TFT touch screen with the resistive system consists of a normal glass panel. A conductive and resistive metallic layer lies above the glass panel. When the monitor is working, an electrical current moves in each of the 2 layers. The conductive and resistive layers are set apart by “spacers” and a scratch-resistant layer is placed on top of the entire setup.

Contact between the two layers happen when the user touches the screen. After contact, the electrical current facilitates coordination and the computer calculates the contact. The user’s touch is translated by a special driver into a language that the operating system can understand.

A TFT touch screen with the capacitive system consists of a ‘capacitive layer’. Electrical charge is stored on the glass panel of the monitor of the capacitive layer. The electrical charge is transferred to the user whenever a touch of a finger is done on the monitor. When this transfer happens, it results to a decrease in charge which is calculated by the computer and translated into information that can be digested by the touch-screen driver software.

The capacitive system is better than the resistive system when it comes to giving out better picture clarity. The capacitive system is able to transmit about 90 percent of the light from the monitor. On the other hand, the resistive system is only able to transmit 75 percent.

A TFT touch screen with the surface acoustic wave system consists of 2 transducers. One transducer sends and the other receives. The monitor glass plate is divided into x and y axes where transducers are located. Reflectors are placed on the glass for the purpose of reflecting electrical signals from one transducer to another. The use of receiver transducers is to determine if the wave has been disturbed by a touch and such touch is located accordingly.

The surface acoustic wave system setup does not have metallic layers on the screen. This results to 100 percent transmission of light providing the best image quality and clarity. Surface acoustic wave TFT touch screen systems are especially best in displaying detailed graphics and are better than the other two discussed earlier.

The cheapest TFT touch screen is the one with a resistive system while the surface acoustic wave setup touch screen is known to be the best TFT touch screen and the most expensive too.