Industrial monitors and industrial PC’s are more often used via a touchscreen. In this area, there is a variety of touchscreen technologies. The selection of the proper TFT touchscreen is essentially dependent on two factors:
- In what type of environment will the touchscreen be used? (i.e. inside, outside, clean room, damp room, in a dusty area)
- How should the touchscreen be used? (i.e. with a finger, gloves or a stylus)
The most common touch technologies in the industry are briefly explained here:
1. Resistive touchscreen
The resistive touchscreen with a 5 wire technology is the industry’s most commonly used touchscreen. Due to the fact that it reacts to pressure on the screen, the resistive touch can not only be used with a finger, but also with gloves and with a pen or stylus.
2. Capacitive touchscreen
The capacitive touchscreen works via a thin conductive layer on top of a glass surface. It is very robust and reliable and therefore as vandal proof as possible. Due to the fact that the touchscreen is made of a layer of glass, it still works with small scratches on the surface. It can only be used however with a finger and is not suited very well for damp rooms
3. Projective Capacitive Touch (PCT Touch)
The Projected Capacitive Touch (PCT Touch) is also a capacitive touchscreen. The big difference lies in fact that a thick pane of glass (up to 8mm) is placed in front of a the display (for example in a showroom window) and the touchscreen can still be used. This way the monitor is not only protected against vandalism and scratches, but also resistant to heat, cold, humidity and strong cleaning agents.
The entire monitor (including housing) can be placed behind a pane of glass. This yields a completely flat and easy to clean surface. In contrast to the capacitive touch, the PCT Touch can be used with a finger as well as thin gloves.
4. Glass Film Glass Touchscreen (GFG Touch)
The GFG Touch works the same way as a resistive touchscreen. In this case, the outer surface is not a film, but a very resilient pane of glass. The film on the resistive Touch, the image is always “milky” right away. That does not happen with the Glass Touch.
The glass pane on the Glass Film Glass Touchscreen is very resilient, is resistant to scratches, alkali and acids and it can be used in an expanded temperature range of -25° to +70°. It can be operated with fingers, gloves and other objects (i.e. chain link gloves or the tip of a knife), without damaging the touchscreen.
A Multi Touch is in principle a Projected Capacitive Touchscreen which can be configured with the proper software for a simultaneous multi station usage.
A Multitouch Display can be operated with fingers as well as gloves.
6. Infrared touch (or IR Touchscreen)
The Infrared Touch (IR Touchscreen), works in a similar way as a “light barrier”. This is located just over the display surface. It is the only touchscreen, that does not require a direct contact with the display. The advantage is: the IR Touch can easily be protected with a protective pane of glass , without compromising the performance of the touchscreen (i.e. bullet proof glass). This makes it almost completely vandal proof. The “light barrier”, however, has one disadvantage: the infrared touchscreen can be activated unintentionally (i.e. with snow or insects).
7. SAW Touch
The SAW Touch works with ultrasound waves. The surface is comprised of a glass pane, which can be exchanged with safety glass. This makes the SAW Touch very robust and allows for a nearly vandal proof installation. The touchscreen, however, can only be operated with a finger or a soft glove.