How do touchscreens work?

     Have you ever wondered how touch screens work? What's going on behind that glossy display? There are half a dozen types of technologies. I will be giving the two most commonly used systems. So let's get started.

1. Resistive

     Resistive touchscreens are the most basic and common touch screens. These touch screens are used in ATMs and supermarkets. These are designed for high durability. It resists your touch by bending slightly. This bending will make the touch screens to work.

     There are two yellow layers. One layer is resistive and the other is conductive. These two layers are separated by spacers. Electric current will be flowing through the layers. when we press the layer, it bends and makes a change in current flow in that particular coordinates. According to the coordinates where the current flow is changed the action is taken accordingly.

  Advantages:

• Durable.
• Lifetime is more.

  Disadvantages:

• Difficult to sense by the system.
• Multiple touches cannot be executed.

2. Capacitive

     Capacitive touchscreens work with anything which can hold an electric charge - including human skin. Capacitive touch screens are constructed from materials like copper or indium tin oxide that store electrical charges in an electrostatic grid of tiny wires.

     There are two types of capacitive touchscreens - surface and projective. Surface capacitive uses sensors at the corners and a thin evenly distributed film across the surface whereas projective capacitive uses a grid of rows and columns with a separate chip for sensing. In both cases, when finger hits the screen a tiny electrical charge is transferred to the finger to complete the circuit. So a voltage drop occurs and the particular location is sensed and required actions are taken.