Surface Acoustic Wave Touchscreen Technology

How Surface Acoustic Wave Works

Also known as simply as acoustic wave, SAW is a form of touchscreen technology that uses ultrasonic acoustic waves (hence the name). Unlike resistive touchscreens, SAW does not rely on the measurement of voltage to determine points of contact. Instead, it constantly emits ultrasonic waves over the surface of the touchscreen. When the user places his or her finger on the surface, some of the waves are absorbed. The SAW touchscreen will then pinpoint the exact location where the ultrasonic waves were absorbed to determine the point of contact.

While the exact method of construction varies depending on the particular type of SAW device, most are comprised of a single glass sheet featuring transmitting transducers, receiving transducers and reflectors.  The transmitting transducers are responsible for creating the ultrasonic waves which pass over the surface of the touchscreen, while the reflectors reflect them and the receiving transducers receive them. It may sound somewhat complicated, but it’s actually a relatively simple process that’s gradually gaining momentum in the touchscreen industry.

Benefits of Surface Acoustic Wave

There are several key benefits to SAW, one of which is its superior strength and durability. Because they are made with glass panels, SAW devices are resilient to scratches, scuffs and other forms of damage. This doesn’t necessarily mean an SAW device will withstand a direct blow from a hammer (although it may), but they are generally stronger than many other types of touchscreen devices.

Disadvantages of Surface Acoustic Wave

Of course, there are also some potential disadvantages to SAW. If liquid, dirt, grime or other contaminants form on the surface of the device, it may  interfere with its ability to identify points of contact. This is why it’s important for users to keep their SAW devices clean and free of debris.

This article should give you a better understanding of surface acoustic wave touchscreen technology. Remember, its defining characteristic is the use of ultrasonic waves to determine points of contact.