Surface acoustic wave (SAW) touchscreens are on the rise. You can find them in restaurants, retail stores, amusement parks, banks and more. Like all touchscreens, SAW touchscreens are able to detect and respond to touch commands. While other types of touchscreens rely on pressure or capacitance to perform these tasks, though, SAW touchscreens use ultrasonic waves.
When you turn on a SAW touchscreen, it will immediately project ultrasonic waves over the display interface. You won’t be able to hear or see these ultrasonic waves. Nonetheless, touching the display interface will disrupt them. The SAW touchscreen will then register the location of this disruption as a touch event. What are SAW touchscreens made of exactly?
SAW touchscreens are made of an all-glass top layer. The uppermost layer isn’t made of plastic, nor is it made of acrylic. While other types of touchscreens may feature a plastic or acrylic top layer, SAW touchscreens feature a top layer made entirely of glass.
With their all-glass top layer, SAW touchscreens offer excellent optical clarity. More light can pass through the top layer of a SAW touchscreen than that of touchscreens with a plastic or acrylic top layer.
In addition to an all-glass top layer, SAW touchscreens feature transducers. They are placed along the perimeter of the top layer. Transducers are responsible for detecting touch commands.
Transducers will project ultrasonic wave across the top layer. As these ultrasonic waves bounce around, sensors will register them. If the sensors fail to detect ultrasonic waves, the SAW touchscreen will register it as a touch event. There are different types of SAW touchscreens, but they all feature a series of transducers.
SAW touchscreens feature backlighting. Backlighting is a lighting system that’s part of the integrated display. Assuming a SAW touchscreen features an integrated display, it will typically feature backlighting as well.
Backlighting will illuminate the pixels in the display. There are a few display technologies that use self-illuminating pixels. Their pixels are essentially electroluminescent, meaning they will illuminate automatically when exposed to an electrical current. But most display technologies don’t use electroluminescent pixels; they require backlighting to illuminate their pixels.
These are just a few parts of a typical SAW touchscreen. SAW touchscreens still feature a circuit board. The circuit board is the main computer chip. Hopefully, this gives you a better understanding of SAW touchscreens and what they are made of.