HAPTIC TECHNOLOGY----technology behind touch sensitive screens

Technology may be the ‘hidden hand’ — no pun intended — of etymology! The term, ‘hands-on computing’ has come to assume a whole new meaning, when your fingers do more than jab at a keyboard; when they interact with the computing surface and receive a reassuringly reciprocal sensation that tells you, that your wish is its command.
Origin of haptics
The ancient Greeks called it ‘haphe’ or ‘haptesthai’ — meaning contact or touch —till now the applications are of high-end industrial applications of haptics… and they have not ‘touched’ lay users — till now. But the explosion in ‘convergence’ devices at the confluence of PC, TV and Internet, has changed all that.
The customer’s demand
The new and emerging customer is saying: “If you want me to use a computer or surf the Internet as easily as I use my television set, then I demand the simplicity of the TV.”Industry has heard the underlying threat in this demand. Which is why Francis Lee, Chief Executive of Synaptics, a leading maker of touch sensors, told the Associated Press last week: “This new ( touch) interface will be like a tsunami, hitting an entire spectrum of devices.” Hewlett Packard’s new TouchSmart IQ770 PC, just launched in India, uses a 19-inch touch-sensitive screen as a user-friendly interface for all its functions — as entertainment centre, home security and control console, Internet browser and as a plain old personal computer. Microsoft which generally touted voice as the emerging personal device interface, has nevertheless made its own ‘touching’ contribution… the ‘Surface,’ a table-top computer whose large plastic-topped surface hides a numbers of scanners, projectors and the heart of a personal computer.
You could read the menu in a hotel, off the table top, touch an item to order it — then eat it at from the same surface. Perhaps the most hyped consumer offering to exploit touch technology is Apple’s i-Phone. This all-in-one, phone-multimedia-Net-access device does away entirely with the mobile phone’s keyboard and substitutes a screen that uses what is known as multi-touch technology. You can slide a finger up and down to scroll through your address book, flick it to open and leaf through a photo album and glide it across the screen to open other applications.
Conventionally, touch sensitive screens are created by embedding a resistive or capacitive layer just beneath the exposed surface. Touching it sets off changes in the electric current that runs between the two layers and knowing the coordinates of the spot touched on a grid, allows the computer to interpret the action.
Today’s tactile technologies have become a bit more sophisticated. For the iPhone, it has deployed a proprietary gesture-enhanced multi-touch technology.