OUTPUTS

1
OUTPUTS

• Intro. to Computer Technologies

2
Objectives

• Upon completion of this lesson, students will be
  able to
• Identify all output plug ins on your computer
• Describe the advantages of CRT monitors
• Describe the advantages of LCD monitors
• Describe the benefits of a Laser Printer

3
What is an Output Device?

• Any device by which a computer transforms its
  information to the "outside world."
• When the device is outside the computers main
  case, we generally call it a peripheral device.
• Peripheral means on the edge or outside of an
  area.

4
Examples of Output Devices

• Monitor
• Printer
• Modems
• Speakers
• Projectors
• Sound Cards
• Video Cards

5
Monitors

• The most frequently used output device.
• The display provides instant feedback by showing
  your text and graphic images as you work or play
• Desktop displays use a cathode ray tube (CRT).
• Laptops use liquid crystal display (LCD)
• Monitors using LCD technologies (also called flat
  panel or flat screen displays) are beginning to
  replace CRT.

6
CRT Refresh Rates

• The number of times that the image on the display
  is drawn each second.
• Refresh rates are very important because they
  control flicker, and you want the refresh rate as
  high as possible.
• Too few cycles per second and you will notice a
  flickering, which can lead to headaches and eye
  strain.
• If your CRT monitor has a refresh rate of 72
  Hertz (Hz), then it cycles through all the pixels
  from top to bottom 72 times a second.

7
Cathode Ray Tube (CRT)

• Size is measured diagonally (corner to corner).
  Today monitors are available in sizes 14", 15",
  17", 21".

8
Advantages of CRT

• Less Expensive -
• Better Color Representation
• CRT displays have historically represented colors
  and different gradations of color more accurately
  than LCD displays.
• Durable
• CRT displays are also
• less fragile and harder
• to damage.

9
Advantages of CRT

• More Responsive
• Fewer problems with ghosting and blurring
• Redrew screen image faster than LCDs
• Multiple Resolutions
• Ability to change your display's resolution
• Viewing Angle

10
From CRT to LCD

• CRT
• Bulky heavy
• Using technology that was developed in the 19th
  century.

• LCD
• First LCD laptop monitors were very small due to
  manufacturing costs.
• Light, sleek, energy-efficient, have sharp
  picture.

11
LCD

• Screen Size
• Measured diagonally from the inside of the
  beveled edge.
• Measurement does not include the casing as
  indicated in the image below
• LCD 17 19 CRT Screen
• Widescreen
• Computer monitors larger than 40

12
Advantages of LCD

• Require less power
• CRT 100 watts for a 19-inch display.
• LCD 45 watts for a 19-inch
• LCDs produce less heat.
• Maintains brightness for 25,000 to 50,000 hrs
• Smaller and weigh less
• Significantly thinner and lighter than a CRT
  monitor,
• Weighing ½ total
• Mount an LCD on a wall

13
Advantages of LCD

• Adjustable
• Tilt
• Height
• Swivel
• Orientation (horizontal to vertical mode)
• Less Eye Strain
• Do not produce a flicker or glare
• Better job of displaying text compared with CRT
  displays.

14
LCD (Liquid Crystal Display)
15
Television and HDTV Integration

• Some displays have built-in television tuners
  that you can use for viewing cable TV on your
  computer.
• You can also find displays that accept S-video
  input directly from a video device.

• Additional features include picture-in-picture or
  picture-on-picture capability, a remote control
  and support for high-definition television
  (HDTV).

16
Resolution

• The number of individual dots of color, known as
  pixels, contained on a display.
• Resolution is affected by a number of factors,
  including size of the screen.

• Expressed by identifying the number of pixels on
  the horizontal axis (rows) and the number on the
  vertical axis (columns), such as 800 x 600.

17
PRINTERS

• The job of a printer is to put on paper what you
  see on your monitor.
• How easy this is to do and how successfully it is
  done determines whether or not you are happy with
  your printer choice.
• Monitor screens and printers do not use the same
  formatting rules.
• In the olden days of computers, the way something
  looked on the screen could be VERY different from
  how it would look when printed.

18
Printers

• Early word processors didn't have a way to show
  what the printed version would look like.
• Nowadays we expect What We See Is What You Get,
  where you see almost exactly what the document
  will look like in print, while you are still
  working on it.

19
Four Types of Printers

• Impact
• Daisy wheel and Dot matrix.
• Direct Thermal
• Fax machines and inexpensive / high-portability
  printers.
• Thermal Ink/Color
• Ink jet and Bubble jet.
• Laser

20
Ink Jet

• Grown in popularity and performance while
  dropping significantly in price.
• Better image quality
• Faster than dot-matrix printers
• Tendency to smear if page gets wet.

21
Inkjet Printers

• An inkjet printer is any printer that places
  extremely small droplets of ink onto paper to
  create an image.
• The dots are extremely small, tinier than the
  diameter of a human hair!
• The dots are positioned very precisely, with
  resolutions of up to 1440x720 dots per inch
  (dpi).
• The dots can have different colors combined
  together to create photo-quality images.

22
Laser Printers

• Similar to a photocopier
• A roller is charged with electricity, then a
  laser is used to remove the charge from portions
  of the roller.
• Powdered ink (toner) sticks to the parts of the
  roller that were hit by the laser, and this toner
  is transferred from the roller to the paper.
• Then the ink is baked into the paper using a
  heater.
• Laser printers produce very high quality output
  and are very fast.

23
Laser Printer
24
All-in-One

• Print, scan and copy from one source
• Faxing available on some models
• Laser technology for fast print speeds and sharp
  output
• Direct printing from digital cameras on select
  models
• Space-saving design

25
Photo Quality Printers

• Comparable to professional photofinishing
• Direct photo printing (select models) from
  compatible digital cameras
• Easy printing for all skill levels
• Auto editing features and output sizes (select
  models)

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How Fast?

• The speed of a printer is measured in
• cps characters per second
• lpm lines per minute
• ppm pages per minute
• The faster the printing, the more expensive the
  printer.

27
Buying a Printer Consider...

• Expense of ink or toner?
• How much does a cartridge cost and how many pages
  will it produce?
• Photo inks are more expensive!
• Number of cartridges?
• One 3-color cartridge or separate black and color
  cartridges or a cartridge for each color

• Output?
• What speed is needed?
• Is heavy-duty equipment necessary?
• Quality of output needed? 
• Resolution needed
• Photo quality?
• Location of printer?
• How big a footprint can be handled?
• Is loudness important?

28
Video/Sound Cards

• Designed to improve upon the onboard video or
  sound.