Touchscreen devices like smartphones, tablet computers and human machine interfaces (HMIs) are all designed to support touch-based commands. Rather than using perhipherals like a keyboard and mouse, you can control them by touching the interface, typically with your finger or a stylus. It’s a simpler, more engaging way to control a device that most users prefer over traditional methods. But there are different types of touchscreen technology used to achieve this goal, one of which is infrared (IR).
IR Grid Touchscreen
IR grid is a type of touchscreen technology that uses a grid-like array of X-Y light-emitting diodes (LEDs) and photodetectors embedded around the edges of the interface. The LEDs produce IR light that travels across the surface of the interface, whereas the photodetectors analyze this light while searching for disruptions in it. When you touch your finger or a stylus on the interface, it disturbs the IR light produced by the LEDs. The photodetectors are then able to determine where exactly you touched, so they respond with the appropriate action (e.g. launch an app or type a letter into a document).
IR Acrylic Projection Touchscreen
A second form of IR touchscreen technology is IR acrylic projection. It works in a similar manner as IR grid by featuring LEDs on the interface’s edges that produce and transmit IR light across the surface. Rather than using photodetectors, however, IR acrylic projection uses special IR-capturing cameras, which are embedded on the back of the device. When you touch the surface of an IR acrylic projection device, it deforms the upper layer of clear, acrylic material, resulting in leakage of the IR light that’s detectable by the cameras. It’s called “IR acrylic projection” because the uppermost layer is made of acrylic. In comparison, IR grid devices do not feature an acrylic layer.
Benefits of IR Touchscreen
Why should you consider an IR touchscreen device rather than a capacitive or resistive touchscreen device? Well, unlike capacitive touchscreen devices, IR devices can be used with a bare finger or gloved finger. This is because they don’t work by measuring changes in capacitance, so there’s no need to use a conductive object, such as your bare finger, to control it. Furthermore, IR touchscreen devices are highly sensitive. While IR grid is more sensitive than IR acrylic projection, both technologies can identify even small, light-pressure touches. These are just a few benefits of using an IR touchscreen device.