Interactive flat panel displays (IFPDs) with infrared touch screens have become increasingly popular in recent years. Compared to the traditional smart projector boards commonly used in education, IFPDs offer greater convenience and practicality. There’s no need for image calibration before a presentation, and with LED lighting technology, IFPDs provide clear, high-quality images. Additionally, the infrared touch screen allows for versatile interaction, whether you're using your finger (dry or wet), a stylus, or even a pen.

In this article, we’ll delve into the features of infrared (IR) touch screens and explore how they can improve user experience.

What Is an Infrared Touch Screen?

An infrared touch screen consists of three primary components: the LCD monitor, the IR touch frame, and the infrared touch overlay.

The overlay, typically a piece of protective glass, is surrounded by the IR touch frame. The frame contains infrared LEDs and photodetectors, and an optical bezel is placed between the glass and the frame to secure the setup and transmit the infrared light emitted by the LEDs.

The IR LEDs emit invisible infrared beams that form grids on the surface of the overlay. The photodetectors, located across from the LEDs, detect interruptions in the infrared beams caused by touch events, enabling the system to recognize user input.

How Does an Infrared Touch Screen Work?

The infrared touchscreen operates by detecting disruptions in the infrared beams emitted by the LEDs embedded around the frame. These beams form a grid over the touchscreen overlay. When a finger or another object interrupts the infrared light, the system detects the disturbance and calculates the x and y coordinates of the touch point, which are then processed by the system.

This technology does not require any special calibration, making it more user-friendly and convenient than traditional systems. Regular maintenance, such as cleaning the overlay, also allows you to check the components and ensure proper functionality.

Installing an Infrared Touch Screen Overlay

To maintain the infrared touchscreen, you will need to clean and occasionally reinstall the interface (overlay). Here’s a step-by-step guide:Remove the screws from the bracket holding the LCD monitor and touchscreen overlay in place.

Take off the bracket carefully.
Place the overlay on a clean, flat surface.
Use a canned air duster to remove dust from the metal frame.
Clean the inner surface of the glass overlay with a mild cleaner (avoid using harsh chemicals).
Wipe the surface of the monitor.
With assistance, carefully reinstall the overlay.
Return the bottom bracket to its original position and secure it with screws.

For a more in-depth look, you can refer to the video below.

Benefits of Infrared Touch Screen Technology

While resistive and capacitive touch technologies are also well-established, infrared (IR) touchscreens offer distinct advantages, particularly in applications like interactive whiteboards and distance learning tools.

Cost-Effective: IR touchscreens are more affordable than other touchscreen technologies, especially for large displays.
Enhanced Display Quality: With no additional layer between the LCD and overlay, IR touchscreens offer superior light transmission, delivering vibrant images without any color or brightness loss.
Multi-Touch Capability: IR touchscreens support up to 40 touchpoints simultaneously, making them ideal for collaborative settings like classrooms or business meetings.
Fast Response Time: Touch event detection and system response times are typically under 8ms, ensuring a quick and accurate user experience.
Better Writing Experience: The overlay, often made of tempered glass, provides a smooth surface for writing.
Scratch-Free: The glass overlay protects the LCD monitor from scratches.
Flexible Customization: The number of LEDs and photodetectors can be adjusted, allowing for customization of the screen size to fit various requirements.
Simple Maintenance: Because there’s no adhesive between the monitor and the overlay, the two parts can be easily separated for cleaning or regular maintenance.
Clear Images: Thanks to the backlit LED system, IR touchscreens deliver clear visuals even in varied lighting conditions.
4K Resolution Support: IR touchscreens can support 4K resolution and work well with high-definition displays.
No Loss of Display Area: Since the LEDs and sensors are embedded around the frame, the display area remains unrestricted.
Versatile Input Options: You can use any non-transparent object (finger, stylus, glove, etc.) to interact with the screen.
No Calibration Required: Unlike traditional projector boards, IR touchscreens do not require regular calibration.
Low-Pressure Input: Writing or drawing on an IR touchscreen requires no pressure, reducing the risk of damage over time.

Infrared vs Capacitive Touch Screens

Infrared and capacitive touch technologies are the two most widely used types, but they differ in several key ways:

Working Mechanism

Capacitive touchscreens use a transparent electrode film between the LCD and cover glass. When the human finger touches the screen, it changes the current in the film, sending position data to the computer. In contrast, infrared screens detect touch by identifying disruptions in the infrared light beams emitted by the LEDs embedded in the frame.

Structure

IR touchscreens often have a bezel to transfer the infrared light, while capacitive touchscreens do not require such a structure.

Multi-Touch Capability

Capacitive screens typically support only two touchpoints, while infrared screens can support up to 40 touchpoints simultaneously.

Activation Method

IR touchscreens can be activated by any object that isn’t transparent, including fingers, gloves, or pens. Capacitive screens, however, only work with bare fingers or thin gloves.

Cost

Capacitive touchscreens tend to be more expensive due to the specialized electrode film required, especially for large screens. IR touchscreens, on the other hand, are more affordable for large interactive displays, making them a popular choice for applications like interactive whiteboards.

Applications

Due to cost-effectiveness and support for multi-touch, IR touchscreens are ideal for large displays used in business presentations, classrooms, and interactive digital signage. Capacitive touchscreens are typically found in smartphones, tablets, and other smaller devices.