Output Devices

Printing

Information on a

paper is known as

“Hard Copy”.

There are two

main types of

printers: - Impact

- Non-Impact.

Impact Printers

Relatively cheap

Slow and Noisy

Quality is not very good

Some types of impact printers:

- Dot Matrix Printer

- Daisywheel.

Dot Matrix Printer

• Dot Matrix Printer contains a

print head that strikes a

ribbon between the page.

Used in offices to print bills

and invoices

A dot matrix printer

Daisy Wheel

The Daisy Wheel printers has printing

characters at the end of the spokes on the

wheel.

Used in some electric typewriters and

printers,

A daisy wheel showing detail of the characters

Non Impact Printers

Non-Impact Printers are much quieter than

impact printers, as their printing heads do not

strike the paper. A little more expensive but

faster and quality is better.

Some non-impact printers are:

- Thermal Printer

- Ink Jet Printer

- Laser Printer

Thermal PrinterComprises of a thermal head that generates

heat to produce a printed image on paper.

Used in calculators and fax machines.

A fax machine uses a thermal printer.

Ink Jet PrintersSprays ink onto the paper

producing a high quality

text and graphics.

Used at home or small

officesInk Jet Printer

Colour cartridge showing inkjet nozzles

Laser PrinterUse a laser beam and dry powered ink to

produce a fine quality print.

Used in schools and large businesses

Soft Copy Output devicesSoft copy output cannot be “touched”

or feltVisual - Monitors/Visual Display Unit

Audio - Speakers

A Cathode Ray Tube (CRT) monitor

A LCD monitor (Liquid Crystal Display)

Visual Display Units (VDU) or monitors are used to visually interface with the computer.

Visual Display Units display images and text which are made up of small blocks of coloured light called pixels (Picture Elements). The resolution of the screen improves as the number of pixels is increased.

Speakers

Speakers output information in the form of sound waves. Computers may also use a sound card to allow for better quality sound.