With most of the discussions around different types of touchscreens, we rarely find any information on the construction of touchscreens. Before we get in to understand the structure of touchscreens, let’s first see how they operate and sense the touch.
You will find resistive and capacitive touchscreens, used commonly in many applications. Where resistive touchscreens identify the point of touch by the pressure created by the operator, capacitive touch screens, on the other hand, use the capacitive trait of the human finger to couple X & Y channels of the capacitive sensor. However, regardless of the type, whether resistive or capacitive, most touchscreen devices are made of three essential layers. These layers are of great significance when it comes to identifying durable touchscreens.
- The uppermost layer is typically coated with a transparent metallic conductive coating on the bottom side, whereas the top layer is either bare glass or polyethylene film sometimes coated with optical enhancements or in the case of polyethylene film, a hard coat to resist scratching. The conductive coating is optically transparent but let electrical charges flow through it.
- The second layer consists of an optically clear adhesive that bonds the first layer to the third layer. In the case of resistive touch screens, this layer is only around the border. The viewable area is an air gap.
- Lastly, the third layer is made of glass with the same conductive coating as the first or top layer. In 5 wire resistive sensors, this layer is the layer where X & Y voltage readings are taken when a touch is made by the user. In capacitive, this layer contains conductive channels similar to the first layer but in opposing orientation where the first layer’s channels and the opposing channels of this third layer form a gride pattern which the user’s finger touch “capacitively couple” together to obtain the X & Y coordinate.
This is just a standard construction pattern of touchscreen devices. While the resistive and capacitive touchscreen devices mostly follow this format, others may not.
When choosing a touchscreen device, don’t worry about the different layers that it contains. Search for key words like “durable touchscreens”, along with features like “high optical clarity”, “water resistant”, etc.
Touchscreens, these days, are available with many innovative features and constructions. You can check with leading manufacturers like A D Metro that offers an extensive range of innovative touch screen technology solutions. A D Metro uses patented technology to provide highly durable touchscreens. For example, ULTRA resistive touchscreens and PCAP touchscreens are some to name of a few.
