The document discusses different types of output devices used in computing. It describes soft copy devices like monitors that display output temporarily, as well as hard copy devices like printers that provide permanent printed output. Specific devices covered include CRT and LCD monitors, dot matrix printers, inkjet printers, and laser printers. It analyzes the key features and differences between these common output hardware components.

2. ASSIGNMENT
NAME: SULTAN SALAHUDDIN ROLL NO: 85
ASSIGNMENT: OUTPUT DEVICES
COLLAGE: GOVT AKL PG COLLAGE MATTA
SUBMITTED BY: SULTAN SALAHUDDIN
SUBMITTED BY; MR AMIN ULLAH

3. OUTPUT DEVICES
An output device is any hardware component that
conveys information to one or more people. Three
commonly used output devices are a printer, a monitor
and speakers.
There are two type of output devices which is the
following:
1.Soft copy devices
2.Hard copy devices

4. Soft copy
Displayed on screen or by other non-permanent
means.
Hard copy
Printed on paper or other permanent media.

5. SOFT COPY OUTPUT DEVICES
Soft copy output devices output information to a
computer monitor or other temporary output device.
Soft copy output devices:
 Monitor
 CRT (cathode ray tube)
 LCD (liquid crystal display)
 Speaker

6. Monitors
The computer monitor, like a television, displays
computer output for a user to view. The monitor has
various names: screen or video display unit. When
purchasing a computer monitor, the following
features are important:
Colour
Size
Resolution

7. Colour:
Monitors can be monochrome, grey scale or
coloured.
Monochrome monitors display images in two
colours one for the background and the other for the
foreground.
The colours can be white, green, or amber
foreground on black background.
Greyscale monitors are a special type of monitor
that displays information's.

8. Resolution:
On way of measuring the quality of a monitor is by
its resolution.
The resolution of a screen is a measure of how
accurately data
can be represented on it. Screens are usually Low
Resolution.
Medium Resolution or High Resolution.

9. Size:
Monitors come in various sizes: 14", 15", 17", 20" and
even larger monitors can be had at higher prices.
 A 15" monitor can display 800 pixels horizontally
and 600 pixels vertically.
A pixel, short for picture element, refers to the dots
that make up the pictures displayed on the screen.
The more pixels per inch, the better the quality of
the picture.

10. Monitor
Specifications

12. Cathode-ray tube (CRT)
Resemble televisions
Use picture tube technology
Less expensive than a LCD
monitor
Take up more desk space and
use more energy than LCD
monitors

13. Cathode-ray tube (CRT) TECHNOLOGY
CRT technology uses electron guns that must be at
distances of over one foot from the screen.
The inside surface of the screen is coated with dots
of phosphors which glow when a stream of
electrons from the electron gun strike them.

14. Liquid Crystal Display (LCD)
Cells sandwiched between two transparent layers form images
Used for notebook computers, PDAs, cellular phones, and personal
computers
More expensive than a CRT monitor
Take up less desk space and use less energy than CRT monitors
Types of LCD monitors:
1. Passive-matrix LCD
2. Active-matrix LCD
3. Gas plasma display
4. Field emission display

15.  Liquid Crystal Display (LCD):
the most popular current technology for flat-screen
display is liquid crystal display (LCD) used for pocket
calculators and digital watches. LCD consists of
liquid crystal material between two glass plates.
Characters are etched on to the inner sheet but
cannot be seen. The user can see them on the outer
sheet only when a current is passed through them.

17. SPEAKERS
Speaker (VOICE OUTPUT DEVICES):
A voice output device convert digital data into speech-like
sounds.
Two types of voice output technology are:
1. Speech coding
2. Speech synthesis

18.  Speech coding:
uses actual human voices speaking words to provide a
digital database of words that can output as voice
sounds.
 Speech synthesis:
uses a set of forty basis speech sounds (called phonemes,
the basic of all speech English) to electronically create
any word.
Human voices are not used to make up a database of
words: the computer converts stored text in voices.

19.  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
WMA MIDI MP3 WAV
Beethoven
Rocky
Hornsby
Cheers
1:15 min
2:56 min
48 sec
15 sec
Click an
icon to play
music.
Click the
icon again
to stop
playing.
Try clicking
on Cheers
while playing
music.

20. VIDEO OUTPUT
Video output is the output of motion video to be
viewed by a computer user. Examples of video output
devices or applications are:
Videoconferencing
Virtual reality
Simulators
Robots
Data projectors

21. HARD COPY OUTPUT DEVICES
Which use for to convert softcopy information's
into hard copy.
1.Printers
2.Dot Matrix Printers
3.Inkjet Printers
4.Laser Printers

22. Printers:
Printer is an output
device, which is used to
print information on
paper.
A printer is a peripheral
device that produces a
physical copy or hard
copy of the computer’s
output.

24. Dot Matrix Printers:
In the market one of the most popular printers is Dot
Matrix Printer. These printers are popular because of their
ease of printing and economical price.
Each character printed is in form of pattern of dots and
head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or
9*9) which come out to form a character that is why it is
called Dot Matrix Printer.

25. Advantages
Inexpensive
Widely Used
Other language characters can be printed
 Disadvantages
Slow Speed
Poor Quality

27. Inkjet Printers
Inkjet printers are non-impact character printers
based on a relatively new technology.
They print characters by spraying small drops of ink
onto paper.
Inkjet printers Produce high quality output with
presentable features.
They make less noise because no hammering is done
and these have many styles of Printing modes
available.
 Colour printing is also possible.

28. Advantages
High quality printing
More reliable
Disadvantages
Expensive as cost per page is high
Slow as compared to laser printer

30. Laser Printers
These are non-impact page printers. They use laser
lights to produce the dots needed to form the
characters to be printed on a page.
 Advantages
Very high speed
Give good graphics quality
Disadvantages
Expensive
Cannot be used to produce multiple copies of a
document in a single printing.