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نسخه کامل مشاهده نسخه کامل : Graphics Workshop - Printers



Vahed
03-09-2007, 16:07
Today, when looking for a perfect printer, you have a choice between two completely different technologies, either a Laser or Ink-Jet printer; I will briefly explain both styles of printer today and what to look for when buying.

Ink-Jet printer - This style of printer uses ink cartridges to spray a fine pattern of ink onto the paper with incredible accuracy. The most common choice for the home user, inkjet printers are cheap to purchase and are good for printing images and photos although they do suffer from a slow printing speed and a lower quality text output in comparison to laser printers. Colour versions of Ink-jets simply spray, (usually) 3 different colours in order to make up any colour they require.

Laser printer - This style of printer uses fine amounts of a dust-like substance called toner in order to create printouts. Basically, this toner is negatively charged in a specific pattern by a fine laser so that when a sheet of paper is fed through the printer, the electrostatic charge pulls the toner material onto the paper in the required pattern - exactly the same printing method as used in a photocopier.

Colour laser printers work in very much the same way, although the process is repeated once for each individual colour. This style of printer is usually bought by home or offer users who require the ability to create a large number of printouts or produce documents that are mainly text only; these users would benefit from the faster print speed and better quality for typed documents. Colour laser printers are still incredibly expensive, unfortunately.

The following factors should be considered when purchasing a printer of either kind:
- Resolution - Uses the same measurement unit as Scanners which we discussed last week, DPI (dots per inch). This is a measure of how many dots the printer can squeeze into every inch of paper to make up the picture, for example, a DPI of 1440 x 720 would mean that the printer could fit 1036800 little dots into every inch square.
- Number of colours - Only really applies to ink-jet printers. Simply a measure of how many colours the printer has access to mix together. For example, most have 3 colours that can be mixed together to make thousands.
- Printer Speed - This is measured in Pages Per Minute (PPM). It shows the buyer how many pages the printer can print in a minute. Figures are often given for black and colour printouts as well as the different quality settings; the speed is measured by printing out a standard industry test page on the printer repeatedly.
- Interface - This is the way in which the printer is connected to the computer. Typically, a choice exists between USB and Parallel types of connection. USB has become the most widely available and is the more modern and technologically superior of the two but check that your computer is USB compatible before purchase.
- Manufacturer - Particularly important when purchasing a printer. The brand will determine how much additional consumables will be to buy at a later date, the after sales service that you may experience and ultimately the overall quality of the printer. My personal favourite at the moment would be Epson, but ask around different shops for advice before purchase.

In addition to the points made above, just take into account all other factors such as price, weight, build quality and factors such as paper types the printer can accept (envelopes, A5 etc). Take your time when visiting each shop, if you´re not hurried in to making a decision, you will be sure to end up with the perfect printer for your individual needs. If one thing needs the most consideration, it would be the first point that I made, whether you choose to go for a Laser or Ink-Jet printer.

Computer Articles 2007