7. Plotter

Plotters are a specialist type of printer which is able to draw high quality images on very large pieces of paper, for example 3 foot wide by 10 foot long.

They are used by engineers, architects and map-makers to draw plans of buildings, diagrams of machines or large scale maps. They can also be used for many other similar tasks.

A plotter differs from a printer in that it draws images using a pen that can be lowered, raised and moved across the paper to form continuous lines. The electronically controlled pen is moved around the paper by computer controlled motors.

There are plotters now which are 'pen-less'. these are used for creating high density drawings such as the one shown in the image above.

There are three different types of plotter:

Flatbed plotters - These hold the paper still while the pens move

Drum plotters - These roll the paper over a cylinder

Pinch-roller plotters - These are a mixture of the two types above

Advantages

• Drawings are of the same quality as if an expert drew them
• Larger sizes of paper can be used than most printers can manage

Disadvantages

• Plotters are slower than printers because each line is drawn separately
• They are often more expensive than printers
• They do not produce very high quality text printouts