Capacitive Touchscreens: Which Type Should You Choose?

Think all capacitive touchscreens are the same? Think again. Capacitive has become the world's leading touchscreen technology. It's used in more smartphones, tablets and human machine interfaces (HMIs) than all other touchscreen technologies. While all capacitive touchscreens use a similar method to detect touch commands, though, they are available in different types.

Surface Capacitive

The most basic type of capacitive touchscreen is surface capacitive. Like with other capacitive touchscreens, surface capacitive touchscreens feature an insulator layer. The insulator layer is the top layer, and it's usually made of glass or plastic. Surface capacitive touchscreens are distinguished from other capacitive touchscreens by their use of a single conductive coating.

The conductive coating is only found on one side of the insulator layer. The other side of the insulator layer is responsible for holding a voltage. When you touch the insulator layer, your finger will absorb some of the voltage. The surface capacitive touchscreen will identify this voltage drop as a touch command.

Projected Capacitive

There are also projected capacitive touchscreens. Projected capacitive touchscreens feature rows and columns of conductive traces. This design results in a grid of thousands of individual keys. The areas where the rows and columns intersect are keys.

When compared to surface capacitive, projected capacitive offers a higher level of accuracy. It can pinpoint exactly where touch commands are performed with greater accuracy thanks to its rows and columns of conductive traces. Some projected capacitive touchscreens are even able to detect touch commands performed while wearing thin gloves. Surface capacitive touchscreens, on the other hand, typically require direct contact with a bare finger - or with another conductive object - to register a touch command.