No longer are computers and electronic devices required to use physical keywords for input; they can now use a touchscreen interface. Touchscreen devices are characterized by the use of a touchscreen interface that, as you may know, supports the use of touch commands. You can tap or touch digital icons displayed on the interface to control the touchscreen device. How does touchscreen technology work exactly?
The Basics of Touchscreen Technology
Touchscreen devices are powered by a specific type of technology that allows them to detect, as well as respond to, touch commands. They typically consist of multiple layers along with a touchscreen controller. The touchscreen controller works by converting the analog signals of a user’s touch commands into digital signals for the device’s computer.
Comparison of the Different Types of Touchscreen Devices
While all touchscreen devices can detect and respond to touch commands, there are several different types of them. Capacitive is the most common type. Reports show that roughly 90% of all touchscreen devices produced and sold are powered by capacitive technology. Capacitive touchscreen devices measure capacitance to detect touch commands. When you touch the interface with a condutive object, such as your finger, the device’s capacitance will drop.
There are several variants of capacitive touchscreen technology, some of which include the following:
- Surface capacitance
- Projected capacitance
- Mutual capacitance
In addition to capacitance, another common type of touchscreen technology is resistive. Resistive touchscreen devices don’t use capacitance to detect touch commands. Rather, they use electrically resistive layers. Touching the interface will force the top layer to press down into the bottom layer, at which point the two conductive traces will meet.
Resistive touchscreen devices are available in a variety of configurations, some of which include three wire, four wire and five wire.
Alternative Touchscreen Technologies
Capacitive and resistive are, by far, the most popular and widely used touchscreen technologies on the market. With that said, there are several alternative touchscreen technologies available.
Surface acoustic wave (SAW) is an alternative touchscreen technology that lives up to its namesake by using acoustic waves to detect touch commands. SAW touchscreen devices have an invisible layer of acoustic waves that run across the surface. Touching or tapping the surface will disturb the sound waves, which the device will detect and register as a touch command.
There’s also infrared (IR) touchscreen devices. IR touchscreen devices work like SAW, but rather than using sound waves, they use IR light.