Accounting for over nine in 10 of all touchscreens shipped globally, capacitive is the world’s most popular type of touchscreen technology. It’s called “capacitive” because it uses capacitance to detect touch commands. When shopping for a capacitive touchscreen, though, you may encounter self-capacitance. A subtype of capacitive technology, it uses capacitance to detect touch commands — just like all capacitive touchscreens. With that said, self-capacitance touchscreens are designed in a specific way that distinguishes them from other capacitive touchscreens.
Overview of Self-Capacitance Touchscreens
Self-capacitance is a type of touchscreen technology that’s able to measure capacitance at each intersection of its sensors. All capacitive touchscreens feature sensors to measure capacitance. When a capacitive touchscreen is turned on, it will emit an electrostatic charge across the display. There are sensors embedded behind the display that track this electrostatic charge. Self-capacitance touchscreens work by measuring capacitance at each of the intersection of its sensors.
The Mechanics of Self-Capacitance Touchscreens
Like mutual capacitance touchscreens, self-capacitance touchscreens have sensors. The sensors are arranged using X and Y coordinates, resulting in the formation of an invisible grid. Mutual capacitance touchscreens, however, don’t measure capacitance at each intersection of its sensors. Self-capacitance touchscreens, on the other hand, do measure capacitance at each intersection of its sensors.
When you touch the display interface of a self-capacitance touchscreen, your finger will draw some of its electrostatic charge. The sensors at the intersection closest to your touch will then register it as a touch command. The self-capacitive touchscreen will notice the drop in capacitance around the sensors, so it will respond by registering your touch command at that location.
Pros and Cons of Self-Capacitance Touchscreens
Self-capacitance touchscreens are highly responsive able to register touch commands performed using little or even no pressure. If you hover your finger close to the display interface, it will draw some of the device’s electrostatic charge.
In addition to being responsive, self-capacitance touchscreens are highly accurate. As previously mentioned, they measure capacitance at each intersection of their respective sensors. This allows them to detect the exact location of a touch command.
On the other hand, most self-capacitance touchscreens don’t support the use of a stylus. Rather, they only work a conductive object, such as a bare finger. If you tap the display interface with a standard stylus, it won’t register your touch command. Rather, you’ll have to use either a bare finger or a special capacitive stylus to control a self-capacitance touchscreen.
