William Sawyer

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(No Transcript)
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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

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Input Output

• Input Hardware
• Devices that translate data into a form the
  computer can process
• Translates words, numbers, sounds, and pictures
  into binary
• Output Hardware
• Devices that translate information processed by
  the computer into a form humans can understand
• Translates binary into words, numbers, sounds,
  and pictures

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Input Hardware Pointing Devices

• Control the position of the cursor or pointer in
  the screen and allow the user to select options
  displayed on the screen

• Mouse is the principal pointing tool
• Ball inside the mouse touches the desktop and
  rolls around
• Two internal rollers touch the ball
• One roller picks up motion in x (up), the other
  in y (down)
• The rollers turn a shaft that spins a disk that
  breaks an LED signal into light pulses that are
  seen by an infrared sensor
• Processor chip in mouse reads the pulses and
  turns it into binary

What is the difference between cursor and
curser?
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Input Hardware Pointing Devices

• Trackball
• A movable ball mounted on top of a stationary
  device
• Good for locations where a mouse couldnt move
  enough
• Requires more frequent cleaning to remove finger
  oils

• Touchpad
• To use slide your finger over this small flat
  surface
• Click by tapping you finger on the surface
• May require more practice to use than a mouse

• Pointing Stick
• Looks like a pencil eraser in the lower center of
  a laptop keyboard

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Input Hardware Pointing Devices

• Touch Screens
• A video display screen sensitized to receive
  input from a finger
• Cruder than a mouse, because fingers are big
• Problems touch screens that show a display that
  is not precisely aligned with the input

• Pen input
• Use a pen-like stylus for input rather than
  typing on a keyboard
• Use handwriting recognition to translate cursive
  writing into data

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Input Hardware

• Light Pen
• A light-sensitive pen-like device that uses a
  wired connection to a computer terminal
• Bring the pen to the desired point on the display
  screen and press a button to identify the screen
  location
• Used in situations that require gloves
• Less crude than a touch screen

• Digitizer
• Uses an electronic pen or puck to convert
  drawings and photos to digital data
• Digitizing tablets are used in architecture

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Input HardwareScanning Reading Devices

• Source Data Entry devices create machine-readable
  data and feed it directly into the computer

• Scanners
• Use light-sensing equipment to translate images
  of text, drawings, and photos into digital form
• Image scanners are used in electronic imaging
• Resolution refers to the image sharpness,
  measured in dots per inch (dpi)
• Flatbed scanners work like photocopiers the
  image is placed on the glass surface, then
  scanned
• Other types are sheet-fed, hand-held, drum, and
  pen scanners

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Input HardwareBar-Code Readers

• Photoelectric (optical) scanners that translate
  bar code symbols into digital code
• The digital code is then sent to a computer
• The computer looks up the item and displays its
  name and pricing info

• Bar code types
• 1D holds up to 16 ASCII characters
• 2D can hold 1,000 to 2,000 ASCII characters
• 3D is bumpy code that differentiates by symbol
  height
• Can be used on metal, hard rubber, other tough
  surfaces

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Input HardwareFax Machines

• Facsimile Transmission Machines scan an image
  and send it as electronic signals over telephone
  lines to a receiving fax, which prints out the
  image on paper
• Dedicated fax machine
• Fax modem

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Input HardwareAudio Input Devices

• Records analog sound and translates it into
  digital files for storage and processing
• Two ways to digitize audio
• Sound Board (card)
• An add-on board in a PC that converts analog
  sound to digital sound, stores it, and plays it
  back to speakers or amp
• MIDI Board
• Stands for Musical Instrument Digital Exchange
• Uses a standard for the interchange between
  musical instruments, synthesizers, and PCs

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Input HardwareWebcams and Video-input Cards

• Webcams
• Video cameras attached to a computer to record
  live moving images then post them to a website in
  real time
• Require special software, usually included with
  the camera
• Frame-grabber video card
• Can capture and digitize 1 frame at a time
• Full-motion video card
• Can convert analog to digital signals at rates up
  to 30 frames per second
• Looks like a motion picture

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Input HardwareDigital Cameras

• Use a light-sensitive processor chip to capture
  photographic images in digital form and store
  them on a small disk in the camera or on flash
  memory cards
• Most can be connected to a PC by USB or FireWire
• Can allow you to take more pictures and decide
  which ones to print and save
• But pictures are subject to loss by diskette or
  flash memory failure or computer virus if you
  store them on the PC

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Input HardwareCamera Phones

• Digital cameras are now on cellphones
• Convenience of being able to take photos, then
  instantly email or message them to someone else
• Can provide instant record of traffic accidents,
  etc

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

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Input Hardware Terminal Types

• Dumb Terminals
• a.k.a. Video Display Terminal (VDT)
• Has display screen and keyboard
• Can do input and output only no data processing
• Intelligent Terminals
• Has screen, keyboard, and memory
• Can perform some local functions
• Internet Terminals
• Powers directly up into a browser
• Web terminal displays web pages on a TV set
• Network computer is a stripped-down PC to connect
  people to networks
• Online game player connects to internet for
  online gaming
• PC/TV merges a full-blown PC with a TV

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

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Input HardwareRFID Tags

• Radio-frequency ID tags are based on an
  identifying tag with a microchip containing
  specific code numbers
• Scanners use radio waves to read them and match
  the codes to a database
• Enables items to be tracked without physical
  contact
• Drivers put RFID tags in cars to automatically
  pay tolls
• FDA is tagging certain drugs with RFID to avoid
  counterfeits
• Carmakers are using it for car electronic keyless
  entry
• RFID tags are implanted under skin of pets to aid
  in recovery and identification when they get lost

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

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Input HardwareBiometrics

• The science of measuring individual body
  characteristics, then using them to identify a
  person through a fingerprint, hand, eye, or
  facial characteristic
• Becoming a big business as more companies become
  concerned about security
• Makes identity theft much more difficult when
  records are identified by biometrics as well as
  passwords
• For more information see
• http//www.xtec.com/home.html
• http//www.l1id.com/
• http//www.precisebiometrics.com/

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

22
Input HardwareSpeech-Recognition Systems

• Uses a microphone or telephone as an input
  device. Converts a persons speech into digital
  signals by comparing against 200,000 or so stored
  patterns.
• Used in places where people need their hands free
  warehouses, car radios, stock exchange trades
• Helpful for people with visual or physical
  disabilities that prevent them from using other
  input devices
• Still not easy enough to use to substitute for
  the mouse/keyboard for fast document processing
• ScanSofts Open Speech Dialog
• Apple Speech Recognition
• ScanSofts Navigon MobileNavigator 5

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

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Output HardwareDisplay Screens

• Making a good choice when choosing a display
• Dot pitch (dp) is the amount of space between
  adjacent pixels (picture elements) on screen
• The closer the pixels, the crisper the image
• Get .25 dp or better
• Resolution refers to the image sharpness
• The more pixels the better the resolution
• Expressed in dots per inch (dpi)
• Color depth or bit depth is the number of bits
  stored in a dot
• The higher the number the more true the colors
• 24-bit color depth is better than 8-bit color
  depth
• Refresh rate is the number of times per second
  the pixels are recharged a higher rate gives
  less flicker

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Output HardwareMonitors

• Cathode Ray Tube (CRT) is a vacuum tube used in a
  computer or terminal display screen
• Watch the PC ads to make sure your monitor is
  included
• Flat panel displays are made of 2 plates of glass
  separated by a layer of liquid crystals that line
  up to transmit or block light
• Preferable to CRTs because they take up less room
  on the desktop
• Latency problems make them less desirable for
  online games players

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Output HardwareMonitors

• Video Standard
• SVGA
• XGA
• SXGA
• UXGA
• QXGA

• Principal resolution (pixels)
• 800 x 600
• 1024 x 768
• 1280 x 1024
• 1600 x 1200
• 2048 x 1536

Carbon nanotube
Internals of a CRT screen
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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

28
Output Hardware

• Softcopy
• Data that is shown on a display screen or is in
  audio or voice form exists electronically
• Output that is ephemeral in nature
• Hardcopy
• Printed and film output
• Output that is more permanent in nature

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Output HardwarePrinters

• Form characters or images by striking a print
  hammer or wheel against an ink ribbon
• Dot matrix printers
• Use drums and toner like in photocopiers
• Page Description Language (PDL)
• PostScript and PCL are PDL types
• Produce crisp, professional pages
• Spray ink from 4 nozzles at high speed
• Quiet, inexpensive color printers
• Often less precise than laser printers
• Low to medium resolution printers that use
  thermal paper that darkens in time

• Impact Printers
• Laser Printers
• Inkjet Printers
• Thermal Printers

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Output HardwarePlotters

• A specialized output device designed to produce
  large high-quality graphics in a variety of
  colors
• The earliest output device that could produce
  graphics
• Pen plotters use one or more colored pens
• Electrostatic plotters lie partially flat on a
  table and use toner like photocopiers
• Large-format plotters are large-scale inkjet
  printers used by graphic artists

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Output HardwareMixed Output

• Sound output
• You need a sound card and sound software
• Good equipment can produce very high-quality 3-D
  sound
• Voice Output
• TTS systems (text to speech) are becoming popular
• Requires a sound card and speakers with TTS
  software
• Video Output
• Requires a powerful processor and a video card
• Video files are large, so a lot of storage is
  needed too.

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)

33
I/O Quality of Life Health Ergonomics

• Ergonomics is the methodology of designing a
  workplace to make working conditions and
  equipment safer and more efficient
• Keyboards must be placed at the correct height
  depending on each workers size
• Monitor refresh rates must be fast enough to
  avoid eyestrain
• Monitor heights must be correct for comfortable
  viewing
• Sound-muffling should be used for loud printers
  to reduce workplace noise
• Wrist rests may help avoid carpal tunnel syndrome

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Future of Input and Output

• This is a fruitful area for research, including
• Intelligent sensors
• More data input from remote locations
• More source data automation
• Input help for the disabled
• More sophisticated touch devices
• Better speech recognition
• Improved digital cameras
• Gesture recognition

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Future of Input and Output

• This is a fruitful area for research, including
• Pattern-recognition and biometric devices
• Brainwave devices
• Better and cheaper display screens
• Improved video on PCs
• 3-Dimensional output
• Miniaturization for improved data transfer speeds
  to I/O devices

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Input Output

• Input and Output What is the difference between
  the two? (pg. 253)
• Classify devices into input or output hardware
• Terminals What is the difference between dumb
  terminals, intelligent terminals and internet
  terminals? (pg. 256)
• RFID What are some applications of RFID
  technology? What are the security and privacy
  concerns of this technology? (pg. 276)
• Biometrics What is it and what are some
  applications of the technology?
• Speech recognition What is it and how does it
  work?
• Screen clarity (dot pitch, resolution (dpi),
  color depth, and refresh rate) Is it better for
  each to be lower or higher? What does each
  measure?
• Softcopy vs Hardcopy
• Ergonomics What is it and why is it important?
  What are some medical conditions that can result
  from computer usage? (pg 289-291)