Chapter 7
8/12/2014
Discovering Computers
Technology in a World of Computers,
Mobile Devices, and the Internet
“You can’t have a better tomorrow if
you are thinking about yesterday all the
time.”
Chapter 7
Input and Output
What Is Output?
• Output is data that has
been processed into a
useful form
What Is Output?
• An output device is any type of hardware
component that conveys information to one or
more people
Display devices
Interactive
whiteboards
Page 308
Figure 7-23
Copyright © Cengage Learning. All rights reserved.
Page 305
Printers
Speakers,
headphones,
and earbuds
Force-feedback
game
controllers
Discovering Computers 2012: Chapter 6
Data projectors
Tactile output
4
1
8/12/2014
Displays
Displays
• A display visually conveys text, graphics, and
video information
• A monitor is a display that is packaged as a
separate peripheral device
• The quality of a display depends primarily on its:
Resolution
• LCD monitor
Response time
Dot pitch
Pages 309 - 310
Figure 7-24
Pages 310 - 311
Copyright © Cengage Learning. All rights reserved.
Display Devices
Brightness
Contrast ratio
Copyright © Cengage Learning. All rights reserved.
Common resolutions found in LCD monitors
• Resolution is the
number of
horizontal and
vertical pixels in a
display device
•
•
•
•
•
•
•
•
•
• A higher
resolution uses a
greater number of
pixels
Discovering Computers
17-19": 1280x1024
20"+: 1600x1200
17" (Widescreen): 1280x800
19" (Widescreen): 1440x900
22" (Widescreen): 1680x1050
23.6" (Widescreen): 1920x1080
23" (Ultra-Widescreen): 2048x1152
24" (Widescreen): 1920x1200
30" (Widescreen): 2560x1600
7
2
8/12/2014
• Response time – the time in milliseconds that it takes to
turn a pixel on or off – The lower the number, the faster
the response time
Displays
• Brightness – Measured in nits; a unit of visible light
intensity equal to one candela(candlepower) per square
meter. The higher the nits, the brighter the images
• Today’s monitors use a digital signal to produce a
picture
• To display the highest quality images, the monitor
should plug into:
• Dot pitch – The distance in millimeters between pixels –
The lower the number, the sharper the image.
• Contrast ratio – the difference in light intensity between
the brightest white and darkest black. (400:1 to 800:1)
Higher contrast ratios – better colors.
• A DVI port
• An HDMI port
• A DisplayPort
Page 311
Displays
Display Devices
• Home users sometimes
use a digital television
(DTV) as a display
• HDTV is the most
advanced form of digital
television
• A Smart TV is an
Internet-enabled HDTV
Page 311
Figure 7-25
Copyright © Cengage Learning. All rights reserved.
Copyright © Cengage Learning. All rights reserved.
• A CRT monitor is a desktop monitor that contains
a cathode-ray tube
• Have a much larger footprint than do LCD monitors
Discovering Computers
12
3
8/12/2014
CRT Monitors
Printers
• What determines the quality of a CRT monitor?
Screen resolution
Text created with a smaller dot pitch is easier
to read
Refresh rate is speed at which monitor redraws
images on screen
• A printer produces
text and graphics on
a physical medium
• Printed information
is called a hard copy,
or printout
• Landscape or portrait
orientation
Next
Printers
Printers
• Before
purchasing a
printer, ask
yourself a
series of
questions
Pages 312 - 313
Figure 7-26
14
Discovering Computers
• A nonimpact printer forms characters and
graphics on a piece of paper without actually
contacting the paper
Copyright © Cengage Learning. All rights reserved.
Ink-jet
printers
Photo
printers
Laser
printers
All-in-one
printers
Thermal
printers
Mobile
printers
Plotters
Largeformat
printers
Page 313
Copyright © Cengage Learning. All rights reserved.
4
8/12/2014
Printers
Printers
• Laser printer
• An ink-jet printer forms characters and graphics by
spraying tiny drops of liquid ink onto a piece of paper
• Color or black-and-white
• Printers with a higher dpi (dots per inch) produce a higher
quality output
• Bubble jet printer
• How is this different
from ink-jet?
Discovering Computers
Printers
High-speed, high-quality
nonimpact printer
Prints text and graphics in
high-quality resolution,
ranging from 1,200 to 2,400 dpi
Typically costs more than
ink-jet printer, but is much
faster
Color/Black & White
Next
17
Printers
• Thermal printer
• An all-in-one printer is a single device that prints,
scans, copies, and in some cases, faxes
Generates images by pushing electrically heated pins
against heat-sensitive paper
• Sometimes called a multifunction printer
Page 318
Figure 7-32
Copyright © Cengage Learning. All rights reserved.
Next
5
8/12/2014
Printers
Printers
• A mobile printer is a small, lightweight, batterypowered printer that allows a mobile user to print
from a mobile device
• A label printer is a small printer that prints on an
adhesive-type material that can be placed on a
variety of items
Page 318
Figure 7-34
Page 318
Figure 7-35
Copyright © Cengage Learning. All rights reserved.
Copyright © Cengage Learning. All rights reserved.
Printers
Printers
• Plotters are used to produce high-quality
drawings
• Large-format printers create photo-realistic
quality color prints
• Impact printers form characters and graphics on a
piece of paper by striking a mechanism against an
inked ribbon that physically contacts the paper
Pages 318 - 319
Figure 7-36
Page 319
Figure 7-37
Copyright © Cengage Learning. All rights reserved.
Copyright © Cengage Learning. All rights reserved.
6
8/12/2014
Printers
Printers
• Line printer
High-speed impact printer
that prints entire line
at a time
Speed measured in lines
per minute (lpm)
• A dot-matrix printer
produces printed
images when tiny wire
pins on a print head
mechanism strike an
inked ribbon
• A line printer prints an
entire line at a time
Discovering Computers
Band printer prints fully
formed characters using a
hammer mechanism
Shuttle-matrix printer is
high-speed printer that
works like dot-matrix
printer
Next
25
Speakers, Headphones, Headsets &
Earbuds
• Audio output device
• http://cnettv.cnet.com/london-3d-printer-showworld-pure-plastic-imagination/9742-1_5350133638.html
Computer component that produces music, speech, or
other sounds
Speakers and headsets are common devices
• http://www.dvice.com/2014-1-16/massive-3dprinter-concept-can-print-house-24-hours
• http://www.wired.com/design/2013/05/3-dprinted-ear-hears/?cid=co7654164
Discovering Computers
27
Next
7
8/12/2014
Other Output Devices
• A data projector is a
device that takes the
text and images
displaying on a
computer or mobile
device screen and
projects them on a
larger screen
Page 320
Figure 7-40
Copyright © Cengage Learning. All rights reserved.
Other Output Devices
• Joysticks, wheels, gamepads, and motion-sensing
game controllers can be considered output
devices when they include force feedback
Other Output Devices
• An interactive
whiteboard is a touchsensitive device,
resembling a dry-erase
board, that displays the
image on a connected
computer screen
Page 321
Figure 7-41
Copyright © Cengage Learning. All rights reserved.
Assistive Technology Input and Output
Head-mounted pointer
Braille printer
• Technology that sends resistance to the device in
response to actions of the user
Page 321
Figure 7-42
Copyright © Cengage Learning. All rights reserved.
Pages 321 - 322
Figures 7-44
Copyright © Cengage Learning. All rights reserved.
8
8/12/2014
Discovering Computers
Technology in a World of Computers,
Mobile Devices, and the Internet
Chapter 7
Input and Output
Chapter 7 Complete
9
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement