The document discusses different types of touch screen technologies. It describes resistive, capacitive, and surface wave touch screens. Resistive touch screens detect pressure on a conductive layer, but have low clarity. Capacitive touch screens store electrical charges and are more responsive, but are more expensive. Surface wave touch screens use ultrasonic waves and have high resolution, but must be touched with a soft stylus. The document provides details on the components, working principles, advantages, and applications of various touch screen technologies.

1. Oriental institute of science and
technology
Touch Screen
Submitted by
Deepansh Agrawal

2. Abstract
My seminar report is based on the technology of touch screen. We
see its use in mobiles, in ATM, in computers etc. The wide use of it
makes it a most important technology to be discussed and also to
understand it. In my seminar report I have include the working as
well as applications and principles of it.

3. Index
• Introduction
• Definition& Types
• Components
• Description
– Resistive touch screen
– Surface wave touch screen.
– Capacitive touch screen

4. Introduction
• We are all aware of touchscreen technology .
• We have seen its use in ATM ,Cellphone, public kiosk
etc.
• This technology is based on GUI(graphical user
interphase).
• “They’re all the rage, they are the buzzword, they are
probably the hottest thing in technological cosmos right
now!”

5. Definition and Types
• 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.
• There are three types of touchscreens
a) Resistive touchscreen.
b) Capacitive touchscreen.
c) Surface touchscreen .

6. Resistive Touchscreen
• A resistive touch screen panel is coated with a thin metallic electrically
conductive and resistive layer that causes a change in the electrical
current which is registered as touch event and sent to the controller
for processing .
• Advantages
•Resistive touchscreen technology works well with
almost any stylus like object.
•Costs are relatively low when compared with active
touchscreen technologies
•Resistive touchscreen technology can be made to
support multi-touch input
Disadvantages
• Low clarity
•Less reliability
•Bad sensitivity

7. Capacitive touchscreen
• A capacitive touch screen panel is coated with a material that stores electrical charges.
When the panel is touched, a small amount of charge is drawn to the point of contact.
Circuits located at each corner of the panel measure the charge and send the
information to the controller for processing.
Advantages
•Since capacitive screens only respond to
materials which are conductive , they can be
cleaned with cloths without accidental
command input. Resistive touchscreen cannot.
•Capacitive touchscreen are more responsive
than resistive touchscreen.
•Disadvantages
•Capacitive touch screens are more expensive to
manufacture and offer a lesser degree of accuracy
than resistive touch screens.
•Capacitive touch screens cannot be used with gloves,
and can fail to sense correctly with even a small
amount of water.

8. Surface wave touchscreen
• Surface wave technology uses ultrasonic waves that pass over the touch
screen panel. When the panel is touched, a portion of the wave is
absorbed. This change in the ultrasonic waves registers the position of the
touch event and sends this information to the controller for processing.
•Advantages
•The surface wave technology had high touch resolution
as well as highest image clarity and is better than other
two types of touch screens.
•Disadvantages
•It must be touched by finger, gloved hand, or soft-tip
stylus, Something, hard like a pen won't work. Not
completely sealable, can be affected by large amounts
of dirt, dust, etc.

9. Application
• It uses in mobiles as input screen .
• Uses in ATM .
• Uses in public kiosk.
• Uses in satellites in some portable devices .