Output Devices

Output Devices

1. Piece of hardware used to display or output data which has been processed/ stored on computer

2. Monitors: Most commonly used. Picture is made from pixels(thousands of coloured dots). Higher number of pixels, better the picture. Modern operating systems can handle a dual monitor setup.

3. Printers: Used to create 'hard' copies of work. Most produce output on paper. (Or CDs/DVDs). Major factor is cost of ink. Ink-jets good for low volume, laser printers more cost-effective.

   • Ink-jet: heats ink - sometimes slightly wet after.
     • Advantages: cheap, more compact than laser, cartridges cheaper than toners, produce good qual photos and faster than DM but not laser.
     • Disadvantages: Noisier than LP but not DM, colour can be slow, printout per page more expensive and cartridges need replacing more than LP, ink may smudge, colours can become saturated (not look the same on screen) and dry out.
   • Laser printer: powdered ink (Toner) fused onto paper by heat and pressure.
     • Advantages: highest quality and fastest and cheapest printouts, and also quietest.
     • Disadvantages: Most expensive to buy, toner more expensive, expensive to repair, fairly bulky, can't use continuous or multi-part stationary to create carbon copies like you can with a DM.
   • Dot-Matrix printer:
     • Advantages: relatively cheap, low operating costs, can print on continuous stationary, create carbon copies using carbonated paper, robust (works in harsh/dirty conditions i.e garage).
     • Disadvantages: Poor print quality, slowest, noisy, cannot produce coloured copies

4. Plotters: specialist type of printer which is able to draw high quality images onto very large pieces of paper, i.e. 3ft by 10ft. Used by engineers, architects. Differs from printer as uses pen that can be lowered, raised and moved to form continuous lines.

   • Flatbed plotters - paper still, pen moves. Drum plotters - roll paper over cylinder. Pinch-roller plotters - mixture of two.
   • Advantages: same quality if expert drew them, large paper
   • Disadvantages: slower than printers, more expensive, not high quality text

5. Speakers: computers fitted with small internal speakers which can produce sounds to alert (mistakes). Sound can also be output through external speakers.

   • Advantages: everyone in the room can hear output, help create atmosphere/ ambience, help blind people use a computer (text to sound)
   • Disadvantages: can disturb others who are trying to work, can be expensive

6. Lights: such as LED (Light Emitting Diodes) can be connected to a computer/ equipment and respond to electrical signals which tell them to switch on/off. Common for icon next to light -> compact -> independent of language (sold anywhere)

   • Advantages: cost effective, provide warning (hearing loss), large range of colours
   • Disadvantages: may break/ wear out so need replacing, loose connection (so doesn't turn on), only indicate simple status