Touchscreen technology can be explained basically very easy: you touch the surface of the screen and the device registeres your input and acts accordingly, but for this to happen there are a lot of technologies running in the background. First let’s see what are the types of touchscreen technologies currently available to end users:

    • capacitive
    • rezistive
    • surface acoustic wave

    1 – Rezistive touch screen

    A capacitive touch screen consists of three layers: screen, a conductive and rezistive metallic layer and a scratch protection layer. The first two layers are spaced together and current runs through them. When you touch and press the surface of the screen, the two layers make contact and the point of contact generates a current that’s then being registered and transformed in coordinates.

    2 – Capacitive touch screen

    This technology places a capacitive (electronically charged) layer over the screen. When you touch the surface of this layer, some of the capacity is transferred to your finger (more is transferred where the contact is more powerful). Sensors on four corners register the decreased capacity and calculate where you touched the screen. Capacitive is better than resistive as it transmits 90% light from the screen, compared to 75%.

    3 – Surface acoustic wave touch screen

    Consists of two transducers, one for sending, one for receiving, mounted across the X and Y axis of the screen and a layer of reflectors that capture what the transducers are receiving. The receiving transducer can ‘see’ if the wave transmitted by the other transducer was perturbed and can translate the change in coordinates. As no metallic layer is user this technology permits the best image clarity but this comes as the cost of price, which is higher than the other two technologies.

    Currently the Resistive touchscreen technology is the cheapest but also the worst when it comes to performance. Capacitive screens are gaining ground but Surface wave acoustic touchscreen is considered to be the future.