2. Introduction to the Technology
History and Development
Components used
Touchscreen Technologies
Comparision Chart
Pros and Cons
Closing Thoughts
3. Touchscreen technology is the direct
manipulation type gesture based technology
An electronic visual display that the user can
control through simple/multi touch gestures
Works independently of what is being
displayed on screen
It allows users to interact directly with what is
being displayed, rather than indirectly using a
mouse or keyboard
4. The first ever touchscreen was developed by E.A Johnson at the
Royal Radar Establishment, Malvern, UK in the late 1960s.
In 1971 Dr. Sam Hurst, founder of Elographics developed the first touch opaque sensor
“Elograph” at the University of Kentucky.
Later in 1974, Hurst in association with his company Elographics came up with the first
real touchscreen featuring a transparent surface.
In 1977, Elographics developed the five-wire resistive technology then with the backing of
Siemens Corporation, developed a curved glass sensor called the touch screen.
5. •The first touchscreen phone was launched in 1992
by IBM.This phone was also referred as the first
smartphone.
•When it was launched, it was launched under the
name Simon Personal Communicator.
•Not just receiving and making phone calls, it was
also able to send e-mails and messages.It also
featured very useful applications like
calendar,appointment scheduler, calculator, world
clock,electronic notepad, address book etc.
7. A touch screen sensor is a clear glass panel
with a touch responsive surface
The touch sensor/panel is placed over a
display screen so that the responsive area of
the panel covers the viewable area of the
video screen.
The sensor generally has an electrical
current or signal going through it and
touching the screen causes a voltage or
signal change
8. 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.
The controller determines what type of
interface/connection you will need on the PC
9. The driver is a software update for the PC
system that allows the touch screen and computer
to work together.
It tells the computer's operating system how
to interpret the touch event information that is
sent from the controller.
Most touch screen drivers today are a mouse-
emulation type driver. This makes touching the
screen the same as clicking your mouse at the
same location on the screen.
This allows the touch screen to work with
existing software and allows new applications to
be developed without the need for touch screen
specific programming.
11. These screens literally “resist” your touch; if you press hard enough
you can feel the screen bend slightly. This is what makes resistive
screens work
The resistive touchscreen consists of a flexible top layer made of
Polyethylene (PET) and a rigid bottom layer made of glass.
When a touch is made, the flexible screen presses down and touches
the bottom layer. A change in electrical current is hence detected and
the coordinates of the point of touch is calculated by the controller
Resistive touch screen panels are generally more affordable but
offer only 75% clarity and the layer can be damaged by sharp objects.
Resistive touchscreens are used in food-service, medical monitoring
devices, portable and handheld products, industrial process control and
instrumentation
12. Capacitive screens work with anything that holds an
electrical charge – including human skin.
Capacitive touch screens are constructed from materials
like copper or indium tin oxide that store electrical charges
in an electrostatic grid of tiny wires, each smaller than a
human hair.
Touching the screen results in a distortion of the
screen's electrostatic field, measurable as a change
in capacitance.
Capacitive touch screens have excellent clarity, and there
are no moving parts to wear out. Liquids, dirt, grease, or
other contaminants do not affect them. Unfortunately,
gloved fingers will not activate the system.
13. Acoustic wave touch screens use transducers mounted at the edge of a
glass panel to emit ultrasonic sound waves along two sides. These waves
are reflected across the surface of the glass and received by sensors.
A finger or other soft tipped stylus absorbs some of the acoustic energy
and the controller measures the amplitude change of the wave to
determine touch location.
Because the panel is all glass there are no layers that can be worn,
giving this technology the highest durability factor and also the highest
clarity.
This technology is recommended for public information kiosks,
computer based training, or other high traffic indoor environments.
14. Infrared touch screens are based on light-beam interruption
technology. Instead of an overlay on the surface, a frame
surrounds the display.
The frame has light sources, or light emitting diodes (LEDs)
on one side and light detectors on the opposite side, creating an
optical grid across the screen.
When an object touches the screen, the invisible light beam is
interrupted, causing a drop in the signal received by the photo
sensors, causing a touch event to be detected.
It is generally used in outdoor applications and Point-Of-Sale
systems which can't rely on a conductor (such as a bare finger)
to activate the touchscreen.
Unlike capacitive touchscreens, infrared touchscreens do
not require any patterning on the glass which increases
durability and optical clarity of the overall system.
15. Type Resistive Capacitive SAW Infrared
DURABILITY 3-5 Years 2 Years 5 Years 5 Years
RESPONSE
TIME
< 10ms < 15ms 10ms < 20ms
ADVANTAGE
Low cost (for small
sizes), can detect any
object
Moderate cost, good
in harsh
environments
Can be deployed to
a curved surfaces
No overlay, Superior
image, can detected
any object which
blocks
DISADVANTAGE
High costs for large
areas, very sensitive
to scratch, low
fidelity and reduces
the visibility of the
screen
Finger activation
only, reduces
illumination, finger
must stay in position
for detection so no
movement
Delicate, expensive
and sensitive to
scratch
Expensive, detection
placed above screen
and sensitive to
ambient light
16. Fast
Direct pointing
to the objects.
Finger or pen is usable
(No cable required)
No keyboard necessary
Suited to: novices, application for
information retrieval etc
User has to sit or stand
closer to the screen
Low Precision
Cost
17. Though the touch screen technology contains some limitations it’s
very user friendly, fast, accurate, easy for the novices & fun to
operate. It has been widely accepted. And now by just modifying
a little it can replace the mouse and key board completely in near
future
