How super sensitive screens get touch-y (Smartphones)

For all of your smartphone-owning life, you've been told you can't use your expensive device while wearing gloves, no matter how low the mercury plummets. You weren't really sure why, you just knew it wasn't going to happen.

And so rocketed sales of fingerless gloves, conductive gloves, and even conductive thread for those brave (or thrifty!) enough to hack their own touch-screen hand coverings.

Then something wonderful happened that obliterated this sad certainty of specialty winterwear dependence forever, and that was Nokia.

Starting with the Nokia Lumia 920 and Nokia Lumia 820, the industry got a smartphone touch screen that could register taps and gestures made with fingernails and many gloves (though I wouldn't try heavy-duty whompers).

Nokia didn't just make the supersensitive screen setting an option for its highest-end phones, either. The budget-friendly Lumia 720 and Lumia 520 incorporate this touch-sensitivity option as well.

For a while, Nokia was alone in the supertouchy screen game, until Huawei introduced itsAscend P2 and Samsung followed suit with its Galaxy S4 flagship Android phone.

It's no coincidence that all these phones emerged with the same capabilities as most of Nokia's Lumia lineup; they use the same touch-screen supplier, Synaptics, a Santa Clara, Calif., company whose technology drives the supersensitive train.

A disturbance in the force

Have you seen a diagram of a mobile phone display? It's a lot more than the cover glass you're worried about shattering when you drop your phone.

There are layers that stack up to form the whole package, from the coated cover glass on top through filters, substrate glass, and screen material, like the LCD or OLED sheaves that actually turn pixels on and off to create the picture you see on the screen.

It also helps to have a basic understanding of how a touch screen works in the first place. There's a lot of electrical engineering involved, but the gist of it is that electrodes in the screen assembly help create and hold an electric field around the screen.

When you touch your phone's face, your fleshy finger -- a conductor in its own right -- disturbs that electric charge where you come in contact with the screen.

In the case of multitouch actions, like pinching and zooming, the screen plots coordinates for multiple points of contact. Synaptics' touch technology recognizes up to 10 points of contact at a time, even though you usually use one or two.

The touch sensors -- which detect your taps -- don't reside alone. There's also the touch controller chip, which zips off your electric signals and coordinates to a more powerful processor that then kicks off a task. So for example, you touch the screen on this icon here, and an instant later, you've opened an app.