In recent years, surface acoustic wave (SAW) has emerged to become one of the leading types of touchscreen technologies on the market. Smartphones, tablets, human machine interfaces (HMIs) and other touchscreen devices now use SAW technology. SAW, however, isn’t the same as other touchscreen technologies. It uses a unique method to detect touch commands that’s not found elsewhere.
The Basics of SAW Touchscreens
SAW touchscreens are characterized by their use of sound waves to detect touch commands. When you perform a touch command, you’ll disrupt the sound waves. The SAW touchscreen will identify and register this disruption as a touch event.
Most touchscreens use capacitive technology to detect touch commands. Rather than sound waves, they release a uniform electrostatic charge across the display interface. SAW touchscreens are the only touchscreen devices that use sound waves to detect touch commands.
How SAW Touchscreens Work
When turned on, a SAW touchscreen will project ultrasonic sound waves across the display interface. You won’t be able to see these sound waves, nor will you be able to hear them. Nonetheless, the SAW touchscreen will project them across the display interface’s surface.
Performing a touch command will result in the sound waves being disrupted. The sound waves are released from the perimeter of the SAW touchscreen’s display interface. They run across the display interface while subsequently covering the entire screen. If you touch or tap the display interface, you’ll disrupt the sound waves. The SAW touchscreen will identify this disruption and register it as a touch event.
Reasons to Choose a SAW Touchscreen
Although they are still relatively new, SAW touchscreens offer several benefits. Most SAW touchscreens, for instance, last a very long time. Since they don’t contain moving parts, they don’t suffer from the same premature wear and tear as other touchscreens.
SAW touchscreens also support the use of a stylus. You can control a SAW touchscreen, in fact, by using any object. Capacitive touchscreens are more restrictive. Unless an object it conductive, you won’t be able to use it to control a capacitive touchscreen.
SAW touchscreens also support high-resolution displays. Most of them use a liquid-crystal display (LCD), which is equipped with a backlighting system. Regardless, they all support high-resolution displays in excess of 4096 x 4096 pixels.
Keep in mind that SAW touchscreens aren’t ideal for outdoor usage. They are more susceptible to scratches from dirt and debris than other types of touchscreens, so they are typically used indoors.