4. What is Output?
• What is output?
4
Ø Data that has been processed into a useful form,
called information
§ Output device is any hardware component that can convey
information to user
5. Display Devices
• What is a display device?
5
Ø Output device that
visually conveys
information
§ Information on display
device sometimes
called soft copy
Ø Monitor houses
display device as
separate peripheral
6. CRT Monitor
• What is a CRT monitor?
6
Ø Contains cathode-ray
tube (CRT)
Ø Screen coated with tiny
dots of phosphor material
§ Each dot consists of a red,
blue, and green phosphor
Ø Common sizes are 15, 17,
19, 21, and 22 inches
§ Viewable size is diagonal
measurement of actual
viewing area
7. CRT Monitor
• What is resolution?
7
Ø Sharpness and clarity of image
Ø Refresh rate is speed at which
monitor redraws
images on screen
Ø Higher resolution makes image
sharper, displays more text on
screen, makes some elements
smaller
8. CRT Monitor
•How does video travel from the processor to a CRT
monitor?
8
Step 1. The
processor sends
digital video data
to the video card.
Step 2. The video card’s
digital-to-analog converter
(DAC) converts the digital
video data to an analog signal.
Step 3. The
analog signal is
sent through a
cable to the CRT
monitor.
Step 4. The
CRT monitor
separates the
analog signal
into red, green,
and blue signals.
Step 5. Electron guns
fire the three color signals
to the front of the CRT.
Step 6. An image is
displayed on the screen when
the electrons hit phosphor
dots on the back of the screen.
Ø Video card (also called a graphics card) converts digital
output from computer into analog video signal
9. CRT Monitor
• What are video standards?
9
Ø Video Electronics Standards Association (VESA)
develops video standards
11. Flat-Panel Displays
• What is a flat panel display?
11
Ø Uses liquid crystal display
§ Also called LCD monitor
Ø Takes up less desk space
than CRT monitor
Ø Consumes less than
one-third the power
12. Flat-Panel Displays
• What about using multiple LCD monitors?
12
Ø Some users position
two or more monitors
side by side or stacked
Ø Allows users to run
multiple applications
simultaneously
13. Flat-Panel Displays
• What are some mobile devices that have
LCD screens?
13
p. 300 Fig. 6-11
Ø Notebooks
Ø Tablet PCs
Ø PDAs
Ø Smart phones
14. Flat-Panel Displays
• What is an electronic book (e-book)?
14
p. 300
Ø Small, book-sized computer that uses LCD screen
Ø Allows users to read, save, highlight, bookmark, and
add notes to online text
Ø Download new book content from Web
15. Flat-Panel Displays
•How do you use an LCD monitor with a video
card?
15
p. 301 Fig. 6-13
Ø Plug monitor into Digital Video Interface (DVI) port
on computer
standard monitor
port S-video port
DVI port
16. Flat-Panel Displays
• What is a gas plasma monitor?
16
p. 302 Fig. 6-14
Ø Displays image by applying voltage to layer of gas
§ Larger screen size and higher display quality than LCD, but
much more expensive
17. Printers
• What is a printer?
17
Ø Output device that
produces text and
graphics on paper
Ø Result is hard copy, or
printout
Ø Two orientations: portrait
and landscape
portrait
landscape
18. Printers
• How do you know which printer to buy?
18
SpeedSpeedSpeedSpeedBudgetBudgetBudgetBudget
Color orColor or
black and whiteblack and white
Color orColor or
black and whiteblack and white
Cost per pageCost per pageCost per pageCost per page
Paper typesPaper types
and sizesand sizes
Paper typesPaper types
and sizesand sizes
Photo printingPhoto printingPhoto printingPhoto printing
GraphicsGraphics
capabilitycapability
GraphicsGraphics
capabilitycapability
SystemSystem
compatibilitycompatibility
SystemSystem
compatibilitycompatibility
– Depends on printing needs
WirelessWireless
capabilitycapability
WirelessWireless
capabilitycapability
Future needsFuture needsFuture needsFuture needs
19. Printers
• What is a dot-matrix printer?
19
Ø Impact printer that produces printed images
when tiny wire pins strike ribbon
§ Impact printer forms
characters by striking
mechanism against inked
ribbon that contacts paper
20. Printers
• What is a line printer?
20
Ø High-speed impact printer
that prints entire line
at a time
Ø Speed measured in lines
per minute (lpm)
§ Band printer prints fully
formed characters using a
hammer mechanism
§ Shuttle-matrix printer is
high-speed printer that
works like dot-matrix
printer
21. Printers
• What is an ink-jet printer?
21
Ø A type of nonimpact printer that
sprays tiny drops of liquid ink
onto paper
§ Nonimpact printer forms
characters and graphics without
striking paper
Ø Prints in black-and-white or color
on a variety of paper types
22. Printers
• What is the resolution of a printer?
22
Ø Sharpness and clarity
Ø Measured by number of dots per inch (dpi) printer
can output
23. Printers
• How does an ink-jet printer work?
23
Step 1. A small
resistor heats the
ink, causing the
ink to boil and
form a vapor
bubble.
Step 2. The
vapor bubble
forces the ink
through the
nozzle.
Step 3. Ink
drops onto the
paper.
Step 4. As the vapor bubble
collapses, fresh ink is drawn into
the firing chamber.
print cartridge
print head
nozzle
firing
chamber
nozzlebubble
resistor
ink ink ink dot
paper
24. Printers
• What is a photo printer?
24
Step 2. Insert
media card into
card reader on
photo printer.
Step 3. Use menu to
select desired image to
print, view it on LCD
screen, edit if necessary,
select size of the print,
and then print image.
Step 4. Remove printed photo
from the printer.
Ø Color printer that produces photo-lab-quality pictures
Click to view Web Link,
click Chapter 6, Click
Web Link from left
navigation, then click
Photo Printers
below Chapter 6
media cards
photo
printer
Click to view video
Step 1. Take photograph with
digital camera and store it on
media card in the camera.
media card
25. Printers
• What is a laser printer?
25
Ø High-speed, high-quality
nonimpact printer
Ø Prints text and graphics in very
high-quality resolution,
ranging from 600 to 2,400 dpi
Ø Typically costs more than
ink-jet printer, but is much
faster
26. Printers
• What is a thermal printer?
26
Ø Generates images by pushing electrically heated pins
against heat-sensitive paper
§ Dye-sublimation printer, (also called a digital photo printer)
uses heat to transfer dye to specially coated paper
professional
home use
27. Printers
• What is a mobile printer?
27
Ø Small, lightweight, battery-powered printer that allows
mobile user to print from notebook computer, Tablet
PC, or PDA while traveling
28. Printers
• What is a label printer?
28
Ø Small printer that prints on adhesive-type material
§ Postage printer has built-in digital scale and prints
postage stamps
Ø Most also print bar codes
29. Printers
• What is a plotter?
29
Ø Sophisticated printer used to produce high-quality
drawings
Ø Large-format printer creates photo-realistic-quality
color prints
30. Printers
• What is wireless printing?
30
Ø Output transmitted to printer wirelessly via infrared
light waves or radio waves
§ Bluetooth printing uses radio waves
§ Devices need to be within 30-foot range
31. Speakers and Headsets
• What is an audio output device?
31
Ø Computer component that produces music, speech, or
other sounds
Ø Speakers and headsets are common devices
32. Speakers and Headsets
• What is voice output?
32
Ø Computer talks to you through speakers on computer
Ø Internet telephony allows you to have conversation
over Web
33. Other Output Devices
• What is a facsimile (fax) machine?
33
Ø Device that transmits and receives documents over
telephone lines
34. Other Output Devices
• What is a fax modem?
34
Ø Modem that allows you to send and receive electronic
documents as faxes
external fax
modem
internal fax card
in system unit
fax machine
35. Other Output Devices
• What is a multifunction peripheral?
35
Ø Provides functionality
of printer, scanner,
copy machine, and
fax machine
36. Other Output Devices
• What is a data projector?
36
Ø Device that takes image
from computer screen
and projects it onto
larger screen
37. Other Output Devices
• What is force feedback?
37
Ø Sends resistance to joystick or wheel in response to
actions of user
38. Output Devices for Physically
Challenged Users
•What other output options are available for
visually impaired users?
38
Ø Change Window settings,
such as increasing size or
changing color of text to
make words easier to read
Ø Blind users can work with
voice output
Ø Braille printer outputs
information in Braille
onto paper
39. • Source : Shelly, Gary B. Discovering
Computers (2004/2005/2006). Thomson
Course Technology. PPT for Chapter 6.
39
