Trying to figure out how a screen protector would allow the charge to flow from the screen to the finger; in order to make a capacitive screen to operate? I know they make gloves; one with conductive fibers inlaid or one with small metal finger tips, both allow the charge to flow from the screen to the finger, thus through the body.
Hopefully, someone can explain how this can happen with a different screen protector. I'm curious....
With the RAZR's "Mutual Capacitance" touch screens there is no actual electrical conduction taking place between your finger and the screen. What these screens do is measure any changes in the capacitance (the ability to hold a static charge) at the grid intersections where tiny capacitors are connected below the screen. By even just bringing your finger near a capacitive junction you create a change in the capacitance similar to how static electricity causes things to attract each other and eventually cling together or discharge with a spark, like when you touch a metal object. You see a capacitor doesn't actually conduct electricity internally, instead it stores a differential of positive and negative electrons (static electricity) on the plates at opposite sides of an insulating barrier. The electrons are held there by the magnetic attractions of the opposing positive and negative charges in a miniature magnetic field, but since the insulator won't let the electrons jump to the other side and mate up with the awaiting oppositely charged electrons, they are in a "static" state waiting for the chance to discharge.
The only conducting of electricity happens outside the capacitor when an electrical connection is made between the two terminals (like your finger and the water faucet). At that moment, the opposing electrons see the electrical connection as the easiest path to that opposite attraction and rush through the wires across the two terminals to neutralize each other. This is why unlike batteries capacitors can dump huge amounts of current (essentially all their stored capacity) in a flash - not much different than the way you get a static shock in the winter or when lightning strikes.
In fact, a lightning strike is a giant capacitor where the cloud holds massive amounts of either negatively or positively charged electrons, and the ground is essentially the opposite pole. When lightning actually strikes, it's because a large enough difference is built up to allow the current to arc across the "terminals (cloud and ground) and release the charge. Since air is a poor conductor of electricity (actually a very good insulator) it acts like the insulator in a solid state capacitor allowing the opposing charges to build up until it's able to arc. Unlike a capacitor though, when lightning strikes it is actually traveling between the poles and through the air (insulator) by jumping from cloud (terminal) to ground (terminal).
The symbol for a capacitor looks like two capital T's on their sides and head to head
View attachment 45858, but with a small space between them to illustrate the two plates (the crosspieces of the T) and the insulator (the gap or air). There is no electrical connection between both sides, so there is no part of the left side that touches the right.
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