Input, Output and Storage Devices

Input, Output and Storage Devices

1. Input Devices

   • Mouse
     • A mouse uses a light source typically an LED and a light detector such as an array of photodiodes to detect movement revative to a surface
   • Microphone
     • Microphones convert sound waves into the audio signal. Microphones have different ways of converting energy but they all share one thing in common the diaphragm.
   • Keyboard
     • Each key on the board has a little electrical switch under it. When you press a key, its switch completes a certain electrical circuit a processor inside the key board records records which circuits were completed and in what order . Then it sends that information to your computer.
   • TouchScreen
     • When you press the touchscreen your fingures put pressure and change in the flow of electricity
   • Webcam
     • A Webcam contains a lens, an image and sound sensor
   • Scanner
     • The light passes through the scanner lens and reaches the CCD sensor. CCD sensor measure the amount of light reflect through the image and covers the light to an analog voltage.
   • Barcode reader
     • The sensor of the barcode scanner deflects the reflected light from the alluminationsystem and generates an analog signal with varying voltage that represents the intensity of the reflection. The converter changes to anolog signal to a digital signal which is fed to the detector.
   • Touchpad
     • It translates the motion of your fingers on a surface in the computer in the same position
   • Light pen
     • It stores the grid coordinates on the point you move past so taht way it captures what you write.

2. Output Devices

   • Speakers
     • when a fluctuating electric current flows through the coil, it becomes a temporary electromagnet, attracted and repelled by the permanent magnet. As the coil moves, it moves the cone back and forth, pumping sound waves into the air
   • Headphones
     • Earbuds work the same way as large headphones but as you would expect, everything inside them (the magnet, the coil of wire, and the disaphgm cone that makes sound) is shurnk down to a smaller size.
   • Monitor
   • printer
     • It makes a laser beam scan back and forth across a drum inside the printer, building up a pattern of static electricity. The static elelctricity attracts onto the page a kind of powdered ink called toner. Finally, as in a photocopier a fuser unit bonds the toner to the paper.
   • Remote Control
     • remote control works by sending a light to the device that is controlling each can be seen only seen by a camera, video camera or phone camera.
   • Projector
     • A projetor works by sending a very bright light through a small LCD screen into a lens witch throws out a huge image on to the wall
   • Plotter
     • By moving
   • Laser
     • Laser is crated when the electrons in atoms in special glasses, crystals or gases absorb energy from an electrical current or another laser and become excited.

3. Storage Devices

   • Smart card
     • A small hard drive typically has only one platter, but each side of it has a magnetic coating. The platters rotate at up to 10,000 revolutions per minute.
   • USB
   • Hard Drive
   • CD
   • Memory stick