The document discusses the history and development of touchscreen technology. It describes Dr. Samuel Hurst inventing the first touch sensor called "Elograph" in 1971. It then discusses the four main types of touchscreen technologies - resistive, surface acoustic wave, capacitive, and infrared - providing details on how each works and their advantages and disadvantages. The document concludes that while touchscreens have some limitations, the technology is very user-friendly and has been widely accepted.

1. Manish bharti
B.TECH (EC)3RD
YEAR
TOUCHSCREEN
TECHNOLOGY

2. IntroductionIntroduction
A TOUCH SCREEN IS AN ELECTRONIC VISUAL
DISPLAY THAT CAN DETECT THE PRESENCE AND
LOCATION OF A TOUCH WITHIN THE DISPLAY AREA.
TOUCH SCREENS CAN SENSE FINGER AND OTHER
PASSIVE OBJECTS, SUCH AS A STYLUS. HOWEVER, IF THE
OBJECT SENSED IS ACTIVE, AS WITH A LIGHT PEN.

3. History & DevelopmentHistory & Development
In 1971 Dr. Sam Hurst, founder of Elographics developed
the first touch opaque sensor “Elograph” at the University of
Kentucky.
In 1974 He developed the first real touch screen.
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.
The new transparent technology, AccuTouch, was later
developed by the founders of Elographics, Dr. Hurst and Bill
Colwell

4. Dr. Samuel HurstDr. Samuel Hurst
The father of the touch screen technology
is Dr. Samuel Hurst. In 1971, while he was
working as an instructor at the University of
Kentucky Research Foundation, he had to read
a great volume of information during the
graduation exams. In an effort to save some
time he invented the first touch sensor that he
called “Еlo graph”(electronic graphics), which
allowed him to enter data faster.

5. First Touch PhoneFirst Touch Phone
Apple was the first with a touch
screen phone in 1983. Jason Ford
of Elo Touch Systems, the
company whose founder invented
touch screen technology, for
providing the touch technology. In
1971, the first "touch sensor" was
developed by Doctor Sam Hurst.

6. First Touch MobileFirst Touch Mobile
The Nokia 7710 is a first touch
screen mobile phone model produced
by Nokia. The 7710 is based on
the Nokia 7700 which was never
released. It is Nokia's first, and so far
only smart phone to run the Series
90 GUI a top the Symbian OS.

7. Types of Touch TechnologiesTypes of Touch Technologies
There are mainly 4 types of touch Technologies:-There are mainly 4 types of touch Technologies:-
1.Resistive1.Resistive
2. Surface acoustic wave2. Surface acoustic wave
3. Capacitive3. Capacitive
4. Infrared4. Infrared

8. ResistiveResistive
 A resistive touch screen panel is composed
of several layers, the most important of which are
two thin, metallic, electrically conductive layers
separated by a narrow gap.
When an object, such as a finger, presses down
on a point on the panel's outer surface the two
metallic layers become connected at that point.
This causes a change in the electrical current,
which is registered as a touch event and sent to
the controller for processing. It is used
in Grocery Stores, Hotels, Restaurants and Retail
Stores.

9. Advantages & Disadvantages of ResistiveAdvantages & Disadvantages of Resistive
AdvantagesAdvantages
◦Cost-effective solution
◦Activated by any stylus
◦Very accurate
◦Low power requirements
◦Liquids won't affect touch screen performance
DisadvantagesDisadvantages
◦Polyester surface can be damaged
◦Lower endurance (35 million touches)

10. Surface Acoustic Wave (SAW)Surface Acoustic Wave (SAW)
Surface acoustic wave (SAW) 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. SAW touch screen technology is suggested for use
in ATMs, Amusement Parks, Gaming Environments, Industrial
Control Rooms etc.

11. Advantages & Disadvantages ofAdvantages & Disadvantages of
SAWSAW
Advantages
◦Durable glass construction
◦High optical clarity
◦Activated by a finger, gloved hand, or soft tip stylus
Disadvantages
◦Moving liquids or condensation can cause false touches
◦Solid contaminants create non-touch areas until removed
◦Doesn't support drag or draw effectively

12. CapacitiveCapacitive
 A capacitive touch screen panel
consists of an insulator such as glass,
coated with a transparent
conductor such as indium tin
oxide (ITO).
 As the human body is also
a conductor, touching the surface of
the screen results in a distortion of
the body's electrostatic field,
measurable as a change
in capacitance.

13. Advantages & Disadvantages ofAdvantages & Disadvantages of
CapacitiveCapacitive
Advantages
◦Scratch resistant, durable surface
◦High endurance (225 million touches)
◦Very accurate
◦Good optical clarity
◦Liquids won't affect touch screen performance
Disadvantages
◦Does not work with gloved fingers or stylus

14. InfraredInfrared
 An infrared touch screen uses an array
of X-Y infrared LED and photo
detector pairs around the edges of thee
screen to detect a disruption in thee pattern
of LED beams.
 Infra-red bezels have proven to be a
very reliable technology for use in
ATMs,Medical Instrumentation and
Transportation Tracking applications.

15. Advantages & Disadvantages of InfraredAdvantages & Disadvantages of Infrared
Touch ScreenTouch Screen
Advantages
-Highest quality of underlying image
-Very high transmittance
-Excellent anti-glare, with use of chemically etched glass
-Can be activated with almost any device
-Higher accuracy than other technologies
-Very high durability and reliability
Disadvantages
-Surface obstructions can cause a false touch
–It is very sensitive and can be activated by stray touches.
–Low resolution
–Parallax problems

16. Touch Screen Technology Comparison ChartTouch Screen Technology Comparison Chart
Resistive Infrared SAW Capacitive
Touch
Resolution
High High Average High
Clarity Average Good Good Good
Operation Finger or Stylus Finger or Stylus Finger or Soft-
tipped Stylus
Finger only
Durability Can be
Damaged by
Sharp Objects
Highly Durable Susceptible to
Dirt and
Moisture
Highly durable

17. Advantages & Disadvantages of all
Touch Technology
Touch screens have several advantages over other pointing devices:
 A touch screen is easy to use (as the user simply touches what he or
she sees on the display).
 Save space as no buttons are required.
 Touching a visual display of choices requires little thinking and is a
form of direct manipulation that is easy to learn.
 Touch screens are the fastest pointing devices.
 Touch screens have easier hand eye coordination than buttons.
 Touch screens are durable in public access and in high volume usage.

18. DISADVANTAGES
Screen has to be really big not to miss things when pressing them with
your finger:
 Big screen leads to low battery life.
 Touch screen means screen can’t be read too well in direct sunlight as it
applies an additional not 100% transparent.
Touch screen devices usually has no additional keys (see the iPhone)
and this means when an app crashes, without crashing the OS, you can’t
get to the main menu as the whole screen becomes unresponsive.
 Most user interfaces are not optimized for thumb operation, so a stylus
in necessary, and this means using two hands
 Screens get very dirty.
 These devices require massive computing power which leads to slow
devices.

19. CONCLUSIONCONCLUSION
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.