Smartphones have become an essential tool in our daily lives. According to one report, over 3.5 billion people worldwide now own a smartphone — and this trend isn’t expected to slow down in the coming years. While there are dozens of types of smartphones, however, nearly all of them feature a touchscreen interface. How do smartphone touchscreens work exactly?

Smartphones Use a Capacitive Touchscreen

Most smartphones are now designed with a capacitive touchscreen. They haven’t always used this modern type of touchscreen technology. In the past, smartphones — as well as most other touchscreens — used resistive technology. It wasn’t until the past decade when capacitive surpassed resistive to become the world’s leading type of touchscreen technology.

The Basics of Capacitive Touchscreens in Smartphones

The capacitive touchscreens used in smartphones are almost identical to those used in other devices, including tablets and human machine interfaces (HMIs). They feature a top layer that’s made of a transparent, insulating material, such as glass or plastic. This layer is coated with an electrically conductive material, the most common of which being indium tin oxide (ITO). When turned on, the capacitive touchscreen will generate a uniform electrostatic field across the top layer, which it measures to detect touch commands.

Touching or tapping the display interface of your smartphone will distort its electrostatic field. Embedded sensors within your smartphone will recognize this distortion, and they’ll respond to it by registering a touch event in the area of the display interface where you touched or tapped.

Capacitive touchscreens are the foundation on which smartphones operate. Most smartphones now use a capacitive touchscreen, which is how you control them.

Why Smartphones Use a Capacitive Touchscreen

Smartphones are designed with a capacitive touchscreen for several reasons. When compared to resistive touchscreens, capacitive touchscreens tend to last longer. Resistive touchscreens use a mechanical method of operation, so they are exposed to greater stress. There are no moving parts with capacitive touchscreens. Rather, capacitive touchscreens use an electrostatic field to detect touch commands. As a result, they are more durable and longer-lasting than their resistive touchscreens.

Another reason smartphones use a capacitive touchscreen is to save space. Capacitive touchscreens support a variety of sizes. They can be designed using a small and slim profile that accommodates most smartphones. Resistive touchscreens, on the other hand, often require a larger size because of their mechanical-based method of operation. These are just a few reasons why smartphones use a capacitive touchscreen.