Think all capacitive touchscreens use the same technology to detect and respond to touch commands? Think again. All capacitive touchscreens leverage a uniform electrostatic field, but there are different capacitive technologies available. Among the most popular are surface capacitive and projected capacitive.
What Is a Surface Capacitive Touchscreen?
A surface capacitive touchscreen is a type of touchscreen that uses surface capacitive technology to detect and respond to touch commands. It’s made of multiple layers. The uppermost layer is the insulator, and it’s typically made of glass. Surface capacitive touchscreens feature conductive traces on one side of this glass insulator layer.
When turned on, surface capacitive touchscreens will apply a uniform electrostatic charge to the insulator. Touching the top of the insulator with a bare finger will distort this electrostatic charge. The human body is an excellent conductor of electricity. Upon placing a bare finger on a surface capacitive touchscreen, your body will absorb some of the electrostatic charge. The surface capacitive touchscreen will then register this change in capacitance as a touch event.
Advantages of Surface Capacitive Touchscreens
Surface capacitive touchscreens offer several advantages. For starters, it’s protected from mechanical wear and tear. There are no moving parts in surface capacitive touchscreens. While other touchscreens, such as resistive, have moving parts, surface capacitive touchscreens do not. And without moving parts, they aren’t susceptible to mechanical wear and tear.
Another advantage of surface capacitive touchscreens is the price. They typically cost less than many other touchscreens. This is because surface capacitive is a relatively basic touchscreen technology. It involves the use of conductive traces on a single side of the insulator.
Disadvantages of Surface Capacitive Touchscreens
When compared to projected capacitive touchscreens, surface capacitive touchscreens are less accurate. Projected capacitive touchscreens offer a superior level of accuracy thanks to their patterned electrodes. They still feature conductive traces, which form the electrodes, but projected capacitive touchscreens contain rows and columns of conductive traces. This grid-like pattern allows them to detect touch commands with greater accuracy than that of surface capacitive touchscreens.
You’ll have to use a bare finger when performing touch commands on a surface capacitive touchscreen. They won’t detect touch commands performed with a gloved finger or stylus. Projected capacitive touchscreens, on the other hand, may support these alternative commands. You can wear thin gloves, such as surgical gloves, when using a projected capacitive touchscreen.