Inkjet printer
An Inkjet printer is a printer for computers. It uses special ink to print on the paper. Another type of printing technology is the Laser printer. Inkjet printers are preferred for printing photos and graphics due to their high-quality color output, whereas laser printers are preferred for printing text due to their high contrast and speed.
Usually, inkjet printers are used by people who print very little. The ink comes in special ink cartridges, which can be very expensive and uneconomical. Also, the ink in the cartridge may dry up. This means that a new cartridge is needed. Three colors of cartridges, which combine magenta, yellow and cyan inks are used to create color tones. A black cartridge is also used for crisp monochrome output. Some professional printers have one or more additional colors for better photo quality, such as light cyan, light magenta, blue, red, green, orange, and grey.
Inkjet printers may use either dye or pigment inks. Pigment inks are less likely to fade, whereas dye inks create more-realistic photos and are less likely to clog the printhead.
Many professionals use inkjet printers to print on very large surfaces (up to 5m width). These printers usually do not use cartridges, but have a continuous supply of ink that could last for a long time. Standard-size (A4 or US Letter) printers with a continuous ink supply are also available. Inkjet printers need special paper. This paper has been treated so that the ink does not smear. Less expensive inkjet printers, which cost a little more than 100 US dollars, are a bargain for users who want to be able to print pages in color. Inkjet printers can be very cheap but the ink can also be rather expensive. Some professional inkjet printers can print on surfaces other than paper, such as CDs/DVDs or plastic cards.
An inkjet printer can print between 300 and 720 DPI (Dots Per Inch). Some newer printers can print at higher resolutions, although the benefit of resolutions beyond 720 DPI may not be noticed by the human eye.
A common problem with inkjet printers is that if the printhead is clogged, banding (stripes) will appear in the printed image. To fix this, the printhead needs to be cleaned using the software included with the printer. This problem occurs most often when the printer has not been used for a long time. To prevent this from happening on rarely-used printers, a cron job can be scheduled to print a purge sheet (an image containing all colors used by the printer) once per day. A small, barely noticeable (usually only noticeable by magnification) amount of banding will occur even with a perfectly clean printhead due to the way the printer works.
Inkjet Printer Media
An Epson inkjet printer
A modern HP Deskjet 2630 all-in-one printer
Schematic diagram of a continuous inkjet printing process
Inkjet heads: disposable head (left) and fixed head (right) with ink cartridge (middle)
Video: covering the printhead nozzles with a rubber cap
Microchips from Epson ink cartridges. These are tiny printed circuit boards; a deposit of black epoxy covers the chip itself.
