Touch screen technology allows users to interact directly with what is displayed on the screen using only a touch. There are several types of touch screen technologies that use different methods to detect touch such as resistive, capacitive, surface wave, and infrared. Touch screens are used in devices such as public information displays, self-service kiosks, and computers. They provide intuitive interfaces with fewer buttons but can lead to lower battery life in devices. Future developments may include holographic touch screens and touch-sensitive wood tables.

1. TOUCH SCREEN TECHNOLOGY
Name : K.Ravi Chandu
Branch: ECE-C
Roll No: 20895A0420
Co-ordinator:
(Dr.Khaja Mujeebuddin Quadry)
(Mr.M Rajan)

2. ❑CONTENTS
◈Introduction
◈History and Development
◈Components of Touch screen
◈Types of Touch Screens
◈Advantages and Disadvantages
◈Applications
◈Future scope
◈Conclusion
◈Reference

3. ❑INTRODUCTION
 A touch screen is a computer display
screen that is Sensitive to human
touch, allowing a user to interact with
the computer by touching pictures or
words on the screen.
 A touch screen is an input device that
allows users to operate a PC by simply
touching the display screen which has a
sensitive glass overlay placed on it .
 A touch screen accepts direct onscreen
inputs.

4. ❑History and Development
 In 1971,the first "touch sensor" was
developed by Docter Sam Hurst(founder of
Elography),while he was an instructor at
the University of Kentucky.
 The University of Kentucky Research
Foundation named it as "Elograph" .
 The "Elograph" was not transparent like
modern touch screens.
 In 1974, the first true touch screen
incorporating a transparent surface came.

5. ❑Block Diagram

6. ❑Components of Touch Screen
A basic Touch screen has three main components:
1.Touch Sensor
2.Controller
3.Software Driver

7. ❑Touch Sensor
 A touch screen sensor is a clear glass
panel with a touch responsive surface
which is placed over a display screen.
 The sensor generally has an electrical
current or signal going through it and
touching the screen causes a voltage
or signal change. This voltage change
is used to determine the location of
the touch to the screen.

8. ❑Controller
 The controller is a small PC card
that connects between the touch
sensor and the PC.
 It takes information from the
touch sensor and translates it
into information that PC can
understand.

9. ❑Software Driver
 The driver is a software that allows the touch screen and computer to
work together.
 It tells the operating system how to interpret the touch event information
that is sent from the controller.
 Most touch screen drivers today are mouse-emulation type drivers. This
makes touching the screen the same as clicking your mouse at the same
location on the screen.

10. ❑Typers of Touch Screens
 RESISTIVE
 CAPACITIVE
 SURFACE WAVE
 INFRARED

11. ❑Resistive Touch Screen
 Resistive touchscreens are pressure sensitive, so they can be
operated with any input device, including a gloved hand or
stylus.
 easily damaged by sharp objects.
 they offer only 75% clarity.

13. ❑Capacitive Touch Screen
 Capacitive screens are resistant to outside elements,
making them very durable.
 capacitive panels must be touched with a finger.
 maintains high clarity.

15. ❑Surface Wave Touch Screen
 Surface wave touch screen are more advanced technology
that provides high durability and can be operated by either
human touch or stylus.
 offers highest clarity.
 considerably more expensive.

17. ❑Infrared Wave Touch Screen
 It use an array of infrared (IR) light-emitting diodes (LEDs) on two
adjacent bezel edges of a display, with photosensors placed on the
two opposite bezel edges to analyze the system and determine a
touch event. The LED and photosensor pairs create a grid of light
beams across the display.
 An object (such as a finger or pen) that touches the screen
interrupts the light beams, causing a measured decrease in light at
the corresponding photosensors. The measured photosensor
outputs can be used to locate a touch-point coordinate.

19. ❑Uses of Touch Screen
 Public Information Displays
 Customer Self-Services
 Computer Based Training
 Assistive Technology

20. ❑Advantages
 Ideal for web browsing, picture and movies.
 Simple user interfaces, which are more intuitive (iPhone
once again is a good example).
 Touchscreen devices have fewer buttons .
❑Diadvantages
 Big screen leads to low battery life.
 These devices require massive computing power which
leads to slow devices and low battery life.

21. ❑Future Scope
Holographic touch screens
Wood Touch Tables

22. ❑References
 Sandbach, David Lee: Position detector constructed
from fabric, European patent EP 0989509A2
 Microtouch Systems, Inc.: Frontally Shielded Capacitive
touch sensor system, United States Patent US5457289
 Microtouch Systems, Inc.: Touchscreen controller with pen
andor finger inputs, United States Patent US5457289