Touchscreen devices that measure a uniform electrostatic field to detect touch commands are known as capacitive touchscreens. During operation, they project a small electrostatic field across the display interface. When a conductive object, such as a bare finger, touches the display interface, the voltage of the electrostatic field changes. Capacitive touchscreens are able to detect touch commands by looking for changes in the electrostatic field.
There are several types of capacitive touchscreens, however. Two of the most common types include self-capacitive and mutual capacitive. Both self-capacitive and mutual capacitive touchscreens use an electrostatic field to detect touch commands. With that said, they differ in a few key ways.
What Is a Self-Capacitive Touchscreen?
A self-capacitive touchscreen is a type of touchscreen device that features a grid of capacitance sensors, with the rows and columns operating separately and independently of each other. Self-capacitive touchscreens are designed to measure the voltage or capacitance of a load. They project a uniform electrostatic field across the display interface. When you perform a touch command, the self-capacitive touchscreen will identify it by looking for a change in the voltage on the grid of capacitance of sensors.
What Is a Mutual Capacitive Touchscreen?
A mutual capacitive touchscreen is a type of touchscreen device that automatically forms a capacitor as the junction of a grid. Mutual capacitive touchscreens leverage the fact that when two conductive objects are near each other, they can hold a charge. Like self-capacitive touchscreens, they feature a grid of capacitor sensors. Mutual capacitive touchscreens have rows and columns of capacitor sensors, which together creates a grid. When you touch the display interface, a capacitor will be formed at the intersection of the nearest grid and row.
Differences Between Self-Capacitive and Mutual Capacitive Touchscreens
Because they are both considered capacitive touchscreens, many people assume that self-capacitive and mutual capacitive touchscreens are the same. While both types of touchscreens do, in fact, use a similar method of operation, they are distinguished from each other in a few ways.
Mutual capacitive touchscreens typically cost less than their self-capacitive counterparts. They use a simpler method of operation that makes them easier to manufacture. In turn, you can expect to pay less for a mutual capacitive touchscreen than a self-capacitive touchscreen.
Self-capacitive touchscreens, on the other hand, are more sensitive than mutual capacitive touchscreens. Self-capacitive touchscreens can detect touch commands performed with less force than that of mutual capacitive touchscreens.
