1. TOUCH SCREEN TECHNOLOGY

2. CONTENTS Introduction History Technologies Construction Development
Ergonomics and usage
Comparison of touch screen technologies
Screen protectors
Conclusion

3. 1.Introduction
A touch screen is an electronic visual display that can detect the presence and location of a touch within the display area.
The term generally refers to touching the display of the device with a finger or hand. Touch screens can also sense other passive objects, such as a stylus.

5. 2.History
In 1971, the first "Touch Sensor" was developed by Doctor Sam Hurst while he was an instructor at the University of Kentucky.
In 1974, the first true touch screen incorporating a transparent surface was developed by Sam Hurst and Elographics.
In 1977, Elographics developed and patented five-wire resistive technology, the most popular touch screen technology in use today.

6. The HP-150 from 1983 was one of the world's earliest commercial touch screen computer.
Until recently, most consumer touch screens could only sense one point of contact at a time, and few have had the capability to sense how hard one is touching.
Historically, the touch screen sensor and its accompanying controller-based firmware have been made available by a wide array of after-market system integrators, and not by display, chip, or motherboard manufacturers.

7. 3.Technologies
There are a variety of Touch-screen technologies. Some of them are,
Resistive
Surface acoustic wave
Capacitive
Infrared
Optical Imaging
Dispersive signal Technology
Acoustic pulse recognition

8. Resistive touch screen
Infrared touch screen

10. 4.Construction
There are several principal ways to build a touch screen. there are typically four layers,
Top polyester layer coated with a transparent metallic conductive coating on the bottom
Adhesive spacer
Glass layer coated with a transparent metallic conductive coating on the top
Adhesive layer on the backside of the glass for mounting.

11. 5.Development
Virtually all of the significant touch screen technology patents were filed during the 1970s and 1980s and have expired.
The development of multipoint touch screens facilitated the tracking of more than one finger on the screen.
With the growing acceptance of many kinds of products with an integral touch screen interface, the marginal cost of touch screen technology is routinely absorbed into the products that incorporate it and is effectively eliminated.

12. 6.Ergonomics and Usage
The different ergonomics due to usage of touch screens are,
Finger stress
Finger nail as stylus
Finger prints
Combined with hap tics
Gorilla arm

13. 7.Comparision of touch screen technologies
We can compare different touch screen technologies based on the following factors,
Durability
Stability
Transparency
Response time
Touch
Intense light resistant
Monitor option
Water proof

14. Intense light-resistant
Technology
4-Wire Resistive
Surface Acoustic Wave
5-Wire Resistive
Infrared
Capacitive
Durability
3 year
5 Year
2 Year
Stability
High
Higher Ok
Transparency
Bad
Good
Installation
Built-in/Onwall
Onwall
Built-in
Touch
Anything
Finger/Pen
Conductive
Intense light-resistant
Response time
<10ms
10ms
<15ms
<20ms
Following Speed
Low
Excursion No
Small
Big
Monitor option
CRT or LCD
CRT or LCD or LED
Waterproof

15. 8.Screen protectors
Its very important to take protection on screens while using touch screens.
Some touch screens, primarily those employed in smart phones, use transparent plastic protectors to prevent any scratches that might be caused by day to day use from becoming permanent.

16. 9.Conclusion
This paper presents the importance, history, different technologies and different aspects in using the touch screens.
Although touch screens provide a natural interface for computer novices, they are unsatisfactory for most applications because the finger is such a relatively large object.

17. …THANK YOU…