- The document discusses various input and output devices used in computers such as keyboards, mice, scanners, digital cameras, printers, monitors, and speakers. - It also discusses potential health issues associated with prolonged use of these devices like repetitive strain injuries and discusses ergonomic practices to prevent such issues like having a comfortable sitting position and adjusting workstations to fit the user. - It provides guidelines for proper ergonomic design of work environments and jobs to prevent injuries and improve productivity.

1. TEACHER : SIR ZEESHAN
ABBAS

2. Teacher: SIR ZEESHAN
ABBAS
Group Members:
UZAIR JAVED
1421-315313
Haris
1421-315224
Muhammad umer
1421-315309

3. 3
 Keyboard.
 Mouse
 Microphone
 Digital Camera
 Scanner

4. KEY BOARD
It is an input device used to enter
data in computer.
Keyboard has many different types of
keys,
Function keys (F1,F2 & so on)
Numeric Keys (1,2,……….)
Symbols (@,&,……….)
Alphanumeric keys (A,a,B,b,…..)
Cursor control (Tab, Enter,…..)

5. 5
The most commonly used input device is the
keyboard on which data is entered by
manually keying in or typing certain keys. A
keyboard typically has 101 or 105 keys.

6. 6
Is a pointing device which is used to control
the movement of a mouse pointer on the
screen to make selections from the screen. A
mouse has one to five buttons. The bottom of
the mouse is flat and contains a mechanism
that detects movement of the mouse.

7. 8
Light pen
•A light pen is a small ‘pen-shaped’ wand,
which contains light sensors.
•It is used to choose objects or commands
on the screen either by pressing it against
the surface of the screen or by pressing a
small switch on its side.
•A signal is sent to the computer, which
then works out the light pen’s exact
location on the screen.
•The advantage of a light pen is that it
doesn’t need a special screen or screen
coating.

8.  Whenever a key is pressed. It will be first converted
in to binary codes. then the desired function will be
performed. Keyboard is an advanced version of type
writer.
KEY BOARD

9. 11
Used by a person to communicate to a
computer.
Person to
computer

10. 12
 The keyboard allows the computer user to enter
words, numbers, punctuation, symbols, and
special function commands into the computer’s
memory.

11. 13
 Touch screens

12. 14
 Often used for applications with
occasional use, for example
 Bank ATMs, Information Kiosks, etc.
 No extra hardware - used for input and
for output
 Can be precise to 1 pixel
 Good for menu choice - not so good for
other functions
 Intuitive to use

13. 15
 BUT
 Tiring if at wrong angle (needs to be 30-
45% from horizontal)
 Get greasy, jammy
 Finger can obscure screen
 Alternative - use stylus to touch screen, or
lightpen

14. 16
 Need more cognitive processing than direct
methods, but can be more efficient
 mouse
 tracker ball
 track point
 touchpad…

15. 17
 Joystick
 The main use of a joystick is
to play computer games by
controlling the way that
something moves on the
screen.

16. 18
Microphones - Speech
Recognition
•Use a microphone to talk to your
computer
•Add a sound card to your computer
•Sound card digitizes audio
input into 0/1s
•A speech recognition program can
process the input and convert it into
machine-recognized commands or
input

17. 19
 Speech recognition is a
type of input in which
the computer recognizes
words spoken into a
microphone.
 Special software and a
microphone are
required.
 Latest technology uses
continuous speech
recognition where the
user does not have to
pause between words.

18. 20
Microphones - Speech
Recognition

19. 21
Digital camera
A digital camera can store many more
pictures than an ordinary camera. Pictures
taken using a digital camera are stored
inside its memory and can be transferred
to a computer by connecting the camera
to it. A digital camera takes pictures by
converting the light passing through the
lens at the front into a digital image.

20. 22
Scanner
A scanner can be used to input pictures
and text into a computer. There are two
main types of scanner; Hand-held and
Flat-bed.

21. 24
Bar codes
•A bar code is a set of lines of different
thicknesses that represent a number
•Bar Code Readers are used to input data from
bar codes. Most products in shops have bar
codes on them
•Bar code readers work by shining a beam of
light on the lines that make up the bar code
and detecting the amount of light that is
reflected back

22.  Bar Codes
 Optical Mark Recognition
 Optical Character Recognition
 Magnetic Ink Character Recognition

23. 26
 Tracker ball,
trackpad, trackpoint
 Less space on
desktop
 Good in moving
environments, e.g.
car, train

25.  Output hardware falls into three categories
1. Permanent output
2. Temporary output
3. Action output
 OUTPUT HARWARE SOLUTION
• Output hardware falls into three categories

26. 29
Displays information from the computer to a
person.

27. 30
 textual information
 visual images - photos, diagrams, icons
 moving images
 sounds - music, voice
 Etc..

28. 31
 Text output
 Graphics output
 Video output
 Audio output

29. 32
 Monitors
 Printers
 Speakers
 Data Projectors

30. 33
 A monitor is a peripheral device which displays
computer output on a screen.
 Screen output is referred to as soft copy.
 Types of monitors:
◦ Cathode-ray tube (CRT)
◦ Liquid Crystal Display (LCD or flat-panel)
CRT LCD

31. 34
 CRT
◦ cathode ray tube
 electron gun shoots a stream of electrons at a
specially phosphor-coated screen
 on impact, the phosphor flares up for a fraction of
a second
 electron gun sweeps across the screen many times
a second
 LCD
◦ liquid crystal display
 one of several types of “flat-panel” displays
 forms output by solidifying crystals and
“backlighting” the image with a light source
◦ TV sets are CRTs and many desktop
monitors use this technology
◦ LCD is primarily used for laptops and other
portable devices

32. 35
 Pixel
◦ picture element (smallest unit of
an image, basically a single dot
on the screen)
 Resolution
◦ number of pixels in the image
◦ Common resolution size is
1024x768
◦ Refresh rate
 how often a CRT’s electron gun
rescans
 LCD displays do not use an electron
gun, so do not perform refreshing
The CRT electron gun
“shoots” 3 electrons at
the screen representing
the amount of red, green
and blue for the pixel

33.  Permanent
Output
Printers
Plotters
• Computer processed information in the form of printed documents an
microfilm a vast selection of hardware is available for its production.

34. 37
 Output devices are peripheral devices that enable
us to view or hear the computer’s processed data.
◦ Visual output – Text, graphics, and video
◦ Audio output – Sounds, music, and
synthesized speech

35. 38
 A printer is a
peripheral device that
produces a physical
copy or hard copy of
the computer’s
output.

36. 39
Inkjet Laser
 Inkjet printer, also
called a bubble-jet,
makes characters by
inserting dots of ink
onto paper
 Letter-quality printouts
 Cost of printer is
inexpensive but ink is
costly
 Laser printer works like a
copier
 Quality determined by
dots per inch (dpi)
produced
 Color printers available
 Expensive initial costs
but cheaper to operate
per page

37. 40
 A plotter is a printer that uses a pen that
moves over a large revolving sheet of paper.
 It is used in engineering, drafting, map
making, and seismology.

38. 41
Summary
• Introduction
• Input Devices
– Keyboard,mouse,joystick,scanners,digital
camera, bar code reader, touch
Sreeen,Speech input device (microphone)
• Output Devices
– Monitor , Speaker, Printers ( different
types)

39. 42
 Audio output is the ability of the computer to
output sound.
 Two components are needed:
◦ Sound card – Plays contents of digitized recordings
◦ Speakers – Attach to sound card

40.  It gives hard copy to the organization for the
routine business
Correspondence, billing and accounting
information.
 For example
 Architects use to computer budget
 Types of printer
 Impact printer
 Desk jet
 dot matrix
 Non impact printers

41.  It gives out in the form of graphs, maps,
charts
and drawings.
 For example
o artists use plotters for the different
sketches.
 Types of plotters
 Flatbed plotter
 Drum plotter

42. 45
 Ink Jet Printer
◦ least expensive, color, slower with a higher per
page cost than laser printers
 Laser Printer
◦ More expensive, faster, lower per page cost than
ink jet,

43. Temporary Output
• Video display and audio responses serve as effective, yet temporary, outp
applications that do not require permanent output.
• Video Display Output
-CRT Monitor
- Flat screen
• Speech Synthesizers

44. Some particular health
concerns for users have arisen
due to increased use of input
and output peripherals in the
past two decades. when people
used only typewriters and pens
for business paperwork, there
were always breaks in actions

45. Some particular health
concerns for users have arisen
due to increased use of input
and output peripherals in the
past two decades. when people
used only typewriters and pens
for business paperwork, there
were always breaks in actions

46.  the typewriter carriage had to be returned at
the end of each line, paper needed to be
changed, and errors had to be manually
corrected .with the advent of computers
especially word processing programs in

47.  Repetitive Strain Injuries occur from repeated
physical movements doing damage to
tendons, nerves, muscles, and other soft
body tissues.
 Another name for the condition is Cumulative
Trauma Disorder.

48.  ,it is possible for a person to spend several
hours typing at a keyboard and looking at the
monitor with little change in hand and body
position .it was not long before workers were
complaining about pain in their wrists and
hands, back and neck aches, and headaches
due to eye strain

49.  Repetitive Strain Injuries occur from repeated
physical movements doing damage to
tendons, nerves, muscles, and other soft
body tissues.
 Another name for the condition is Cumulative
Trauma Disorder.

50.  Repetitive Strain Injury (RSI)
◦ is pain or nerve problems in upper extremity (hands, arms,
or shoulders)
◦ can also include neck and back
◦ is a soft tissue disease (muscles and nerves)
◦ is an overuse syndrome
 Symptoms:
◦ burning, numbness, tingling, pins-and-needles
◦ dull aching OR specific, intense pain
 Controversial:
◦ many deny it exists
◦ sufferers receive little support from employers

51.  Tightness, discomfort, stiffness, or pain in
the hands, wrists, fingers, forearms, or
elbows.
 Tingling, coldness, or numbness in the
hands.
 Clumsiness or loss of strength and
coordination in the hands.
 Pain that wakes you up at night.
 Feeling a need to massage your hands,
wrists, and arms.

52. Don’t rest
the wrist on
anything
while
typing.

53. A dangerous occupation:
This is also dangerous:
As a typical computer user, you “walk”
several miles each day on your fingertips
(250 keystrokes / min) * (2 in / keystroke) * 4 hours = 2 miles

54.  Ensure that the operator has a
comfortable sitting position sufficiently
flexible to reach, use, and observe the
display screen, keyboard, and
document.
 Provide posture support for the back,
arms, legs, and feet, and adjustable
display screens and keyboards.
 Ensure that the Video Display Terminals
(VDT) tables or desk are vertically
adjustable to allow for operator
adjustment of the screen and keyboard.
 Ensure proper chair height and support
to the lower region of the back.
 Ensure that document holders are used
to allow the operator to position and
view material without straining the eyes
or neck, shoulder, and back muscles.

56. stress

57. ulnar deviation dorsiflexion
pronation
slouching

58.  Since monitors were introduced in late
1970s,people have been concerned about the
effects of extremely low frequency (ELF)
emissions from these screens

59.  . Rumors of miscarriages and brain tumors
are caused by VDT emissions have yet to be
substantiated by medical researchers .at the
very least , many users find that the glare
from the screen causes eyestrain and
headaches.

60.  ERGO=“work”
 NOMICS=
“rules” or “laws”
 Ergonomics literally
means “the laws of work”

61.  Ergonomics is the science (and art) of fitting
the work environment of the employee. By
improving the match between the work
environment and the employee, you can
expect improved employee comfort, reduce
changes for occupational injuries, improved
productivity, and improved employee job
satisfaction.

62.  OSHA defines ergonomics as the science of
“designing the job to fit the worker,
instead of forcing the worker to fit the
job.”

63.  Ergonomics is way to work smarter—Not
harder by designing of tools, equipment,
workstations and tasks to fit the job to the
worker.—NOT the worker to the job.
 Layout/type of controls and displays.
 Lighting and temperature
 Process (heights, reaches and weight)

64.  Ergonomics is the science (and art) of fitting
the work environment of the employee. By
improving the match between the work
environment and the employee, you can
expect improved employee comfort, reduce
changes for occupational injuries, improved
productivity, and improved employee job
satisfaction.

65.  The goal of ergonomic is to design jobs to fit
people. Something is ergonomically design, if
its optimized to fit people. this means taking
account of differences such as size, strength
and ability to handle information for a wide
range of users. Then the tasks, The
workplace and the tools are designed around
these differences.

66.  Ideally, ergonomics:
◦ Makes the job safer by preventing injury and
illness
◦ Makes the job easier by adjusting the job to the
worker
◦ Makes the job more pleasant by reducing
physical and mental stress
◦ Saves money $$$

67.  Awkward posture: If a job tasks looks
uncomfortable, it probably is and this
increases the chances for injuries. whenever
possible, strive to arrange the work
environment of work processes to allow
employees to work from comfortable, neutral
posture, Excessive bending, reaching
awkward neck, back, and arm positions
should be eliminated.

68.  Is concerned with reduction of one or more
of the following risk factors.

69.  Two Categories of Ergonomic Factors
1. Environmental
2. Physical

70.  Environmental factors may affect:
◦ Hearing
◦ Vision
◦ General comfort and health

71.  Some examples of ergonomic
environmental problems are:
◦ Sick Building Syndrome
◦ Excessive noise
◦ Improper lighting
◦ Temperature extremes

72. What are some of the environmental
factors that might effect your work
area?

73.  Physical stressors place pressure or stress
on parts of the body:
◦ Joints, muscles, nerves, tendons, bones
 Sometimes these injuries are referred to as
“Cumulative Trauma Disorders” (CTDs) or
“Repetitive Strain Injuries” (RSIs)

74.  Cumulative = occurring gradually over a
period of weeks, months, or years
 Trauma = bodily injury to nerves,
tissues, tendons, or joints
 Disorders = physical ailments or
abnormal conditions

75.  Examples of Cumulative Trauma Disorders
include:
 Carpal Tunnel Syndrome
 Epicondylitis
 Tenosynovitis
 Bursitis

76.  The main risk factors for office-related
CTDs are:
 Repetition
 Awkward positions or posture
 Excessive pressure or force
 Another risk factor for CTDs would be:
 Vibration

77.  The majority of CTDs are caused by
repetitive motions that would not result
in injury if only performed once.
 Thousands of keystrokes typing
 Hours of filing, day after day
 Stamping dozens of papers
 Frequent lifting
 Repeated motions with computer mouse