touch screen

TOUCH SCREENS

Represented by: Affan

Naim Roll:

114005

Comp. Sc & Engg

Orissa Engineering College

INTRODUCTION HISTORY WORKING TECHNOLOGIES COMPARISON APPLICATION CONCLUSION

OVERVIEW

INTRODUCTION

HISTORY

In 1971, the first touch screen developed by SAM HURST.

The HP-150 from 1983 was probably the world’s earliest commercial touch screen computer.

HOW DOES A TOUCH SCREEN WORK

HOW DOES A TOUCH SCREEN WORK

TOUCH SENSOR

The controller connects between the touch sensor and the PC

Take information from the touch sensor and translate it into information that PC can understand.

CONTROLLER

The driver is a software that allows the touch screen and computer to work together

SOFTWARE DRIVER

Resistive Capacitive Infrared Surface

Acoustic Wave

TECHNOLOGIES

RESISTIVE

A resistive touchscreen panel is composed of several layers.

It consists of a glass that is coated with electrically conductive and resistive layers.

Lower Cost. Can operate with any pointing

devices like stylus and nails. Good for hand writing recognition

system.

Advantages of Resistive touch screen technology…

Can be relatively easily damaged by scratching.

It emits only 75% of light which make the image relatively bulky and dim

Disadvantages of Resistive touch screen technology…

It consist of glass panel with capacitive (charge storing) material coating on its surface.

Circuits located at the corners of the screen measure capacitance of a person touching the overlay.

CAPACITIVE

Visibility of the capacitive touch screen is good even in sunlight.

Highly sensitive to finger touch leading to easy to use.

Highly transmissivity transmit more than 85% of light.

Advantages of Capacitive touch screen technology…

It is expensive Can not be used with gloved

hand and stylus. Need to have at least 5%

humidity to achieve capacitive effect.

Disadvantages of Capacitive

touch screen technology…

The infrared touch screen uses an array of X-Y infrared LED and photo detector pairs around the edges of the screen to detect a disruption in the pattern of LED beams.

INFRARED

Best image quality Almost all kind of stylus materials

can be used. High stability, change in time and

environment will not effect.

Advantages of Infrared touch screen technology…

High pressure may causes unwanted target selection.

Infrared touch screen has low resolution.

Disadvantages of Infrared touch screen technology…

Surface wave technology uses ultrasonic wave that passes over the touch screen panel.

Widely used in application such as computer based training and information.

SURFACE ACOUSTIC WAVE

High resolution. SAW technology provides

superior image quality. Highly transmissivity transmit

more than 92% of light.

Advantages of SAW touch screen technology…

Relatively expansive in comparison to other technology.

It must be touched by finger, gloved hand and soft stylus, something hard like a pen, credit card or finger nail won’t work.

Disadvantages of SAW touch screen technology…

COMPARISON

Smart phones ATM’s Airline ticket terminals Restaurants.

APPLICATION

Designers are trying to use touch screen to simplify inputs commands.

Today, touch screen has become adopted by computers users of all abilities because it is simple, fast and innovative.

CONCLUSION

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