Infrared grid (IR) and resistive are two of the most common touchscreen technologies. They are used to power everything from tablet computers to human machine interfaces (HMIs) and more. While they both support touch commands, though, they aren’t the same.
What Is an IR Touchscreen?
An IR touchscreen is a type of touchscreen device that uses light-emitting diodes (LEDs) and sensors to detect touch commands. IR touchscreens look like most other touchscreens. The difference is that they use LEDs and sensors to detect touch commands.
Around the perimeter of an IR touchscreen is an array of LEDs with sensors on the opposite side. When turned on, the IR touchscreen’s LEDs will project IR light across the display interface where it’s picked up by the corresponding sensors on the opposite side. Touching the display interface will block the IR light in the area of your touch command.
IR touchscreens essentially create an invisible grid of IR light on the display interface. When the IR light is disrupted, the IR touchscreen will register a touch command in the respective area.
What Is a Resistive Touchscreen?
A resistive touchscreen is a type of touchscreen device that’s comprised of two layers of non-conductive material. They have a top layer — the display interface layer — as well as an underlying layer. Both of these layers contain electrical contacts. Touching the top layer will cause it to press down into the bottom layer. When this occurs, their electrical contacts will complete a circuit, thereby registering your touch command.
Even though they are made of a non-conductive material, resistive touchscreens still use electricity to detect touch commands. Both layers have conductive contacts. The bottom layer, however, has a voltage that passes to the top layer when a touch command occurs.
Differences Between IR and Resistive Touchscreens
IR and resistive touchscreens use different methods to detect touch commands. IR touchscreens use LEDs and sensors. Touching the display interface of an IR touchscreen will block the light, thus allowing the device to pinpoint when and where your touch occurred.
Resistive touchscreens, on the other hand, use two layers of non-conductive material to detect touch commands. They often have backlighting, but resistive touchscreens don’t use light or sensors to detect touch commands. Instead, they respond to pressure. Pressure from the application of a finger or a stylus will force the two layers together.