Types of Computer Printer

 

Basically there are two forms of computer printer:

 

 

Impact Printers

 

These are called impact printers because they actually impact on the surface of the paper via a ribbon. These printers include dot matrix printers and daisy wheel printers.

 

Dot Matrix Printers

 

 

 

Dot matrix come in two types 9 pin and 24 pin and two widths; normal and wide carriage.

 

The number of pins relates to the number of vertical pins in the print head, therefore the higher (24 pin) gives better quality. These pins strike a ribbon which in turn strikes the paper producing the printed characters. But due to the use of the pins the resolution is limited and the use of a ribbon limits the amount of colours and tones available.

These are rarely seen much today as their limited resolution and colour space and loud noise, when in use, have made these printers unpopular, and with the drop in the prices of ink jet printers with their almost silent use and far higher resolution these printers have become redundant, certainly for printing photographs.

 

These printers are more used in distribution where their noise and lack of resolution is not seen as a problem.

 

 

Daisy Wheel Printers

 

 

Developed in the late 1960s, these are basically typewriters that have no keyboard,with a fixed number of characters (as found on the daisy wheel) and take their instructions from the computer.

 

They are limited to only the characters that are on their wheel, hence the name daisy wheel.

 

Because they cannot be used to print out photographs I am not covering them here.

 

 

 

Non Impact Printers

 

With these printers, the print head does not touch the paper.  These include inkjet, laser and dye sublimation printers.

 

 

Inkjet Printers

Since their introduction in the latter half of the 1980s, inkjet printers have grown in popularity and performance while dropping significantly in price. Prior to inkjet printers (referred to as Bubble jet printers by Canon) the main type of printer in homes was dot matrix printers.

 

An inkjet printer is any printer that places extremely small droplets of ink onto paper to create an image. If you ever look at a piece of paper that has come out of an inkjet printer, you know that:

 

• The dots are extremely small (usually between 50 and 60 microns in diameter), so small that they are tinier than the diameter of a human hair (70 microns)!
• The dots are positioned very precisely, with resolutions of up to 1440x720 dots per inch (dpi).
• The dots can have different colours combined together to create photo-quality images.

Some inkjet printers use four colours (Cyan, Magenta, Yellow and Black) others have additional colours like light magenta, light cyan and different tones of grey to produce more accurate colours and tones in the final photograph.

 

My printer is an Epson Stylus 860, like the inkjet printer shown above.  Although the printer is about ten years old it is still a good printer and can produce good prints, but very cheaply at £5.00 per black and colour ink cartridge.

 

 

Dye Sublimation Printers

 

 

These printers are becoming popular with people who simply want to print out their photographs, sometimes directly from the camera, without any post production.

 

The way that they work is not a new process, which is based on thermal printers.

 

A dye-sublimation printer is a computer printer which employs a printing process that uses heat to transfer dye onto a medium materials such as a plastic card, paper, or fabric. The sublimation name is applied because the dye transitions between the solid and gas states without going through a liquid stage. Many consumer and professional dye-sublimation printers are designed and used for producing photographic prints.

Most dye-sublimation printers use CMYO (Cyan Magenta Yellow Over coating) colours, which differs from the more recognized CMYK colours in that the black dye is eliminated in favour of a clear over coating. This over coating (which has numerous names depending on the manufacturer) is also stored on the ribbon and is effectively a thin laminate which protects the print from discoloration from UV light and the air, while also rendering the print water-resistant.

 

 

Laser Printers

 

 

 

Although these printers can produce colour prints, the initial cost of the printer and the costs of the consumables, both toner and photo receptor units, prevents them from becoming more popular.

 

Colour laser printers are developed and designed to work well in offices. They are best used for crisp black text printing and colour graphics. But lasers can print photos successfully as well. It all depends on what type of user is asking.

 

A photo professional will tell the difference between a colour laser printer photo and a professional photo printer one right away.