Input & Output Devices Notes

Input Devices

  • Definition: Data or instructions used by a computer.
  • Function: Translate data into a processable form for the system unit.
  • Examples: Keyboards, mice, pointing devices, scanning devices, image capturing devices, audio input devices.

Keyboard Entry

  • Traditional, laptop, virtual, and thumb keyboards.

Pointing Devices

  • Provide intuitive interface via pointing gestures.
  • Types:
    • Mouse (optical, wireless)
    • Touch pads
    • Touch screens (stylus)
    • Game controllers (joysticks, gaming mice, game pads, motion sensing devices).

Scanning Devices

  • Convert scanned data into processable form.
    • Optical scanners (flatbed, document, portable, 3D).
    • Card readers (magnetic, smart).
    • Barcode readers (wand, UPC, MaxiCode).
    • RFID readers: Use radio-frequency identification to read embedded tags.
    • Character and Mark Recognition Readers:
      • MICR (magnetic-ink character recognition): Used in banking for checks.
      • OCR (optical-character recognition): Reads preprinted characters.
      • OMR (optical-mark recognition): Senses marks on test scoring sheets.
        *NFC Reader: Uses close-range radio signals for communication.
      • Contactless Payments, Access Control, Public Transportation.

Image Capturing Devices

  • Create/capture original images.
    • Digital cameras.
    • Webcams.

Audio-Input Devices

  • Use microphone, sound card, and software to input audio.
    • Smart phones (Siri, Cortana, Google Now).

Biometric Authentication Devices

  • Authenticate identity by translating personal characteristics into digital codes.
    • Fingerprint readers
    • Face recognition systems
    • Hand geometry systems
    • Voice verification systems
    • Signature verification systems
    • Iris recognition systems

Output Devices

  • Definition: Processed data or information.
  • Types: Text, graphics/photos, audio & video.
  • Examples: Monitors, printers, audio-output devices.

Monitors

  • Present visual images (soft copy).
  • Features: Clarity, resolution/pixels, dot pitch, contrast ratios, size, aspect ratio.
  • Types:
    • Flat-panel (LCD, LED, OLED)
    • Curved monitors
    • E-book readers (e-ink technology)
    • Digital/interactive whiteboards
    • Ultra High-definition television (UHDTV)
    • Digital Projectors

Printers

  • Translates processed information (hard copy).
  • Features: Resolution, color, speed, memory, duplex printing.
  • Types:
    • Non-Impact Printers
      • Ink-jet printers
      • Laser printers
      • Thermal printers
      • 3D printers
      • Plotters
      • Cloud printers
    • Impact Printers
      • Daisy wheel printer
      • Dot-matrix printer
      • Line printer
      • Teletypewriter

Audio and Video Devices

  • Translate audio into understandable sounds.
    • Speakers
    • Headphones
    • Bluetooth Technology

Combination Input & Output Devices

  • Headsets
  • Multifunctional devices (MFD)
  • Telephones (VoIP, Hangouts, Face Time, Skype).
  • Drones
  • Robots
  • Virtual Reality (VR headgear and gloves).

Ergonomics

  • Study of human factors related to device usage.
  • Goal: Fit task to user to avoid:
    • Eyestrain and headache
    • Back and neck pain
    • Repetitive strain injury

Ergonomic Challenges

  • Portable devices are not set up for ergonomics.
    • Laptops
    • Tablets
    • Smartphones