What is infrared touch screen?
What is infrared touch screen? - Table of contents:
Not all touchscreen devices use capacitive or resistive technology. While these are the two most popular types of touch-sensing technology, there are others available, including infrared (IR). So, what is infrared touch screen exactly, and how does it work?
What is infrared touch screen?
An infrared touch screen consists of an LCD monitor, IR touch frame, and an infrared touch overlay.
Commonly, the overlay is a piece of protective glass hemmed in by the IR touch frame, in which Infrared LEDs and photo-detectors are embedded. A kind of optical bezel will be inserted between the glass and the frame to fix the frame and transmit infrared light emitted by those LEDs.
Through the optical bezel, IR LEDs emit invisible infrared beams forming grids on the surface of the overlay, Photo-detectors are installed across from the LEDs to detect interruptions of beams if touch events on the overlay happen.
How does infrared touch screen work ?
The IR touch screen works by detecting interruptions of infrared beams emitted by LEDs embedded in the frame around the touchscreen overlay.
There are two rows of IR LEDs, which generate horizontal and vertical invisible IR beams. They form a large beam grid that covers the surface of the overlay. In the meantime, two rows of photo receptors are installed on the opposite side of the LEDs.
As long as an opaque object touches the surface, it will blot out the light beams. Photo-receptors in both directions (vertical and horizontal) can detect this interruption by that object, finally localize the x and y coordinates, and then send the signal to the processor to respond with relevant action.
How To Install An Infrared Touch Screen Interface (Overlay)?
Maintenance is a good solution to sustain the equipment with an IR touchscreen, however, it entails cleaning and installing the interface (overlay).
1. First, you need to remove screws from the bracket, which is used to fix the LCD monitor and touchscreen overlay.
2. Second, remove the bracket
3. Third, put the overlay on a flat workbench.
4. Clean the dust inside the sheet metal frame with a canned air duster
5. Clean the inside surface of the glass overlay, by using mild cleaner only, do not use chemical solvents
6. Clean the surface of the monitor
7. with the help of a partner, gently install the overlay back
8. return the bottom bracket to its original position
9. secure the bracket with new screws
Benefits Of Infrared Touch Screen Technology
Besides IR touch, resistive touch and capacitive touch in today’s market are also mature technology, which performs stably.
Resistive or capacitive touch screen technology exists even longer than IR touch screens.
But, why do engineers choose IR touch screen for interactive whiteboards, which are widely used for business meetings and distance learning? Here are some benefits of infrared touch screens.
* Economical option – compared to other touch screens, the cost of IR touch screens is relatively cheap in large size.
* Better display – without other substance between the LCD and overlay, IR touch screens offer the best light transmission, so they can render more vivid images without color and brightness loss.
* Supports multi-touch – with windows and android 9.0 double OS, it can support as many as 40 touch-points simultaneously. That means it can support up to 4 students interacting together on an interactive touch display.
* Short response time – commonly less than 8ms, IR touch screens localized touch events by detecting light interruption, so they are accurate and quick to respond with actions.
* Better writing experience – its overlay is often a piece of tempered glass, and it is smooth to write on it.
* Free of scratches – since the LCD monitor is protected by glass overlay, you can rest assured that there will no scratches problems
* More flexible in customizing screen sizes – by adjusting the numbers of LEDs and photo-detectors embedded in the overlay frame, you can fit any custom-made monitor with an infrared touch interface
* Maintenance – there is no adhesive substance between the monitor and overlay, so you can disassemble the two parts freely by releasing a few screws when doing regular maintenance, such as cleaning the surface, and wiping dust.
* Clear images – compared with many camera or projector-based systems, equipment with IR touch screens often adopts backlight LED. So, wherever the lighting environment they perform in, they can provide clear images to the audience.
* 4K resolution – they can support 4K resolution screens and work well with high-pixel monitors
* No loss of screen display – Since LEDs and sensors are designed to be fixed in the frame that is around the monitor, the screen can display an unrestricted view.
* Write with any object – you can write on an IR touch screen with anything, a bare finger, a gloved finger, wet hands, or a pen, as long as it is not transparent.
* No calibration – a traditional smart projector board may require regular calibration to display correct pictures, however, devices with IR touchscreen do not need to calibrate the IR LEDs and sensors to guarantee a normal function.
* No pressure is required to write – Resistive touch screen technology perceives the writing track by pressure, which can damage the screen after a long time of usage, while IR touch screen technology by detecting light interruption, so you can write freely without having to push hard on the screen.