TOUCH SCREENS

TOUCH SCREENS, EVOLUTION AND TYPES

Call it an effort of human mind or a miracle from human heart. But this is all happening with technology. We land in an era where everything that can be possibly thought, can also be practically put into. And that too quite reasonably..!! Just move the hand or walk your fingers over a thing and it works.  Its hard to believe that just a few decades ago, touchscreen technology could only be found in science fiction books and film. These days, it's almost unfathomable how we once got through our daily tasks without a trusty tablet or smartphone nearby, but it doesn't stop there. Touchscreens really are everywhere. Homes, cars, restaurants, stores, planes, wherever—they fill our lives in spaces public and private.It wasn’t long ago when we used a stylus with a palm top to perform some operations on it .in 2007 Apple introduced touch screen. It was a big revolution as we could actually slide our fingers against Now we not only take touch input for granted, we expect to be able to use multi touch (using more than one finger on the screen at a time) and gestures as well. What made this touch screen revolution possible?

What are touch screens?

                                                A touch screen is a computer display screen that is also an input device. The screens are sensitive to pressure; a user interacts with the computer by touching pictures or words on the screen.

Evolution:

 EVOLUTION FROM FIRST TOUCH SCREEN TILL NOW:

THERE ARE 2 TYPES OF TOUCH SCREENS :

Ø  Resistive touch screens

Ø  Capacitive touch screens

Resistive touch screens:

The traditional touch screen technology is analog resistive. Electrical resistance refers to how easily electricity can pass through a material. These panels work by detecting how much the resistance to current changes when a point is touched.

This process is accomplished by having two separate layers. Typically, the bottom layer is made of glass and the top layer is a plastic film. When you push down on the film, it makes contact with the glass and completes a circuit.

The glass and plastic film are each covered with a grid of electrical conductors. These can be fine metal wires, but more often they are made of a thin film of transparent conductor material. In most cases, this material is indium tin oxide (ITO)

Capacitive:

These screens are made from multiple layers of glass. The inner layer conducts electricity and so does the outer layer, so effectively the screen behaves like two electrical conductors separated by an insulator—in other words, a capacitor. When you bring your finger up to the screen, you alter the electrical field by a certain amount that varies according to where your hand is. Capacitive screens can be touched in more than one place at once. Unlike most other types of touchscreen, they don't work if you touch them with a plastic stylus (because the plastic is an insulator and stops your hand from affecting the electric field).