Touchscreen monitors allow for a quick, intuitive navigation and are used in places like museums, hotel room automation, and self-serve kiosks. They’re also commonly used by graphic and video professionals.
The touchscreen is comprised of a hard protective layer that preserves the actual display and an electronic grid that identifies inputs given by users. There are a few different types of touchscreens.
1. Capacitive
Capacitive touchscreens use a layer of transparent, electrically conductive material — usually indium tin oxide (ITO) — on top of an insulator such as glass. When you touch the screen, your finger forms a capacitor that changes the screen’s electrostatic field. The device interprets these changes to pinpoint your touch location.
They work with bare fingers or conductive stylus pens, and they’re typically more durable than resistive screens. They also offer superior image clarity and support multi-touch gestures.
They have a low ‘parasitic’ capacitance (the amount of electricity they store between their “plates”), so moisture on the screen, high humidity, and collected dust don’t cause problems. They also feature long term drift compensation, which minimizes the effects of slowly changing environmental conditions.
2. Resistive
Resistive touchscreens use an older technology that relies on pressure to register touch input. They consist of two layers separated by an air gap and coated with a special resistive-yet electrically conductive material. When an object touches the screen, it touches both layers and changes the corresponding electrical signals, which the display controller then interprets as an X- and Y- plane coordinate map of the touch point.
They’re less sensitive than capacitive screens, but they work well with gloves and styluses, making them a good choice for industrial settings where users wear them or otherwise can’t push a mechanical button. They also withstand moisture and dust better than capacitive screens, although they’re not immune to damage caused by abrasion or scratching. Check out more at Faytech North America now!
The most common types of resistive touchscreens are analog 4- and 5-wire, both of which feature a touch controller that uses both electrode film layers to triangulate the location of a touch point. The analog 4-wire version is the most cost-efficient, while the analog 5-wire offers increased durability and ruggedness.
3. Infrared
IR touch screen technology combines LED lights and sensors into the touchscreen frame, making it an inexpensive solution for interactive flat panel displays. This touchscreen technology works with bare fingers, gloves, and styluses as well as liquid-resistant objects such as paper and plastic.
When a finger touches the screen, it interrupts the infrared emission grid’s invisible lattice of light beams, which are detected by photo transistors on the touch screen overlay. The onboard controller then processes the interrupted beam data, determining precise X and Y coordinates to display on the screen.
Unlike capacitive screens, which require a separate layer of electrode film to work, IR touch screens use the sensors and LEDs already built into the monitor. This makes them more immune to surface contamination, reducing the need for frequent calibration and repair over time. IR touch screens can also display an unobstructed image without additional layers covering the screen. They are a cost-effective alternative to projector-based smart board systems used in business meetings.
4. Acoustic
Surface Acoustic Wave touch screen monitors use ultra-sonic waves to detect touch. When a finger touches the touchscreen, it interrupts the acoustic waves, which causes a change in the signal and alerts the system to the location of the touch.
The display consists of a clear glass panel with vertical and horizontal ultrasonic senders and receivers. When a finger touches the touchscreen, the digitized sound is compared with a list of sounds corresponding to each position on the screen, indicating the touch location. Extraneous noise is ignored because it does not match any of the stored signals.
While acoustic-based touchscreens were popular some time ago, they have been largely superseded by those using Projected Capacitive technology. However, they continue to offer several advantages including durability and optical clarity. Their all-glass construction makes them less susceptible to damage due to scratches or dust. In addition, they tend to have better resistance to moisture than resistive screens.