How Do Touch Screen Monitors Senses User Touch
How Do Touch Screen Monitors Senses User Touch - Today touch screen system are embedded on most of the electronic devices like Smartphone, touch screen monitors, PDA, Laptops and others. The reason behind such extensive use is due to decrease in the price of touch materials. The touch system works on three basic systems – Resistive, Capacitive and Surface acoustic wave.
Touch Screen Resistive System functionality
A Normal glass panel covered with two layers i.e. Conductive and resistive metallic, separated by spacers are the key concept behind resistive touch system. A scratch resistance layer is placed at the top of the whole setup. An electrical current passes through the two layers when monitor is on running condition. When a user touches the screen, the two layers make contact in the exact spot. As a result a change in the electrical pulses is noted and the exact coordinate contact point is calculated by computer system. A special driver translates the touch contact into data understood by operating system.
Touch Screen Capacitive System functionality
In capacitive system, a layer which has the capability of storing electrical charge is attached with the glass panel of the touch screen. When a user touches the monitor few amount of charge is transferred to the user, as a result charge of capacitive layer is decreased. The circuit located at the corner experience the decrease in charge. Now due to the relative difference in charge, computer can calculate the exact position where touch event takes place. The touch screen driver will decode the actual task done by the user to the operating system.
Surface Acoustic Wave System
In Surface acoustic wave system, two transducers are placed along the x and y axis of the monitor glass panel. A reflector is placed on the glass plate which reflects an electrical signal sent from one transducer to the other. The receiving transducer will not only experience the disturbance on the touch panel but also accurately locate the place of disturbance. No metallic layer on the screen plate allows 100 % light throughput and perfect image clarity.
When we talk about register response at the time of touch event, the resistive system register a touch event as long as the two layers make contact. This is the very reason of touch event takes place by finger or with a rubber ball. But in case of capacitive system, the touch event takes place only by finger.