In 2017, we are so used to the concept of capacitive touch based interfaces on our smartphones that we do not even take a moment to consider how innovative and stunning it seemed to all of us when the technology first debuted a decade ago with the LG Prada and was later made popular by the first iPhone in 2007. Have you ever wondered how that YouTube icon recognises your touch and opens up or how exactly a doodling app manages to trace your finger so accurately? If you have then read on to understand the electronics at work behind the modern smartphone display.
The capacitive touchscreen has completely replaced resistive touchscreens of the old days, but why are they called “capacitive” touchscreens? The answer to that question is that all capacitive touchscreens contain and function with the help of a capacitor. The capacitor is a piece of electronics that has the ability to store electric charge in it for a short amount of time. Basically, a capacitor is created by placing an insulator in between two conductive layers and that’s basically how every smartphone touchscreen works nowadays. On some phones, you can actually see the capacitive setup (an array of dots below the glass) under bright light, if you hold it at the right angle.
The Touch Response
Our skin is a conductor of electricity, so when we touch the glass above the capacitive setup, the charge at the juncture of the capacitor is decreased, causing the embedded microprocessor to automatically detect the activated contact points and send the same information to the Operating System or the concerned application. The programming in the concerned software then reacts to that information, which results in the user seeing the desired effect on screen. If you have a locked iPhone or any other locked smartphone for that matter, you will notice that there are some options on them that you can see but cannot activate, like you would be able to on an unlocked version of the same phone. In such cases, phone unlocking is the best option as it frees your OS and your phone in general from all touch restrictive coding.
Why General Gloves Don’t Work
Although a few glove manufacturers do claim that the user can operate smartphone displays even when wearing their gloves during the winter, they may not always work as well as we would like them to. As most of you have already figured out from the explanation above, gloved fingers don’t work with capacitive touchscreens simply because unlike the human skin, gloves are insulators and you need to touch a capacitive screen with a conductor to successfully and accurately register a touch. However, if your phone or any other device has a resistive touchscreen, it won’t matter what you are touching it with because resistive touchscreens work on the principle of pressure and not electric conduction.
If you have ever used a cracked display without any issues and have wondered how that’s possible, then know that it’s possible because the cracks you see are on the outside glass and not on the capacitive layer, which is placed below the front glass and over the actual display panel. On the other hand, if you somehow manage to damage the capacitor, you will need a new display to use your smartphone.