Page 17 - DCAP105_WORKSHOP_ON_COMPUTER_HARDWARE_AND_NETWORK

Unit 1: Introduction to Hardware and Software

On the basis of the way impressions are made on the paper, printers are of two types: Notes
 Impact printers: In these types of printers, printing takes place by striking at the paper
through a ribbon soaked in ink. The impression on the paper is created by pressing a rigid
object over an ink-soaked ribbon.

 Non-impact printers: In this type of printers there is no physical touch of any object on the
paper. On the basis of how much is printed in a single operation, printers are of three
types:

 Character printers: These types of printers are capable of printing one character or letter
at a time. The conventional typewriter also types a letter at a time.

 Line printers: These printers can print one line of characters or letters in one go. Line
printers are obviously much faster than character printers. However, they are more
expensive than character printers.
 Page printers: As the name suggests page printers can print the whole page at one time.
These printers are fastest but costliest at the same time.
 Dot Matrix Printer (High Speed Printer): Dot matrix printers are impact printers. The
printer head has an assembly of a fixed number of pins and tiny hammers. These hammers
strike at the pins, which in turn make impression of dots on the paper loaded in the printer
through an ink-soaked ribbon.

 Inkjet printer: This type of printer belongs to non-impact class. Characters are formed as
a result of electrically charged or heated ink being sprayed in fine jets onto the paper. The
printer head consists of nozzles. Individual nozzles produce high resolution (up to 400
dots per inch or 400 dpi) dot matrix characters. Magnetized plates in the ink’s path direct
the ink onto the paper in the desired shape. Inkjet printers are capable of producing high
quality print approaching that produced by laser printers.
 Laser printer: This printer also belongs to non-impact type. A drum is initially electrically
charged and then a high intensity laser beam is used to discharge selected areas on the
drum where nothing is to be printed. These discharged areas correspond to the white area
of the printed document. Dry ink or toner is attracted to parts of the drum with a high
charge. The drum rotates and transfers the toner to the paper which has an even greater
electrical charge. Finally a heater fixes the toner onto the paper. After printing this page
the drum is cleaned by de-electrifying it. The process continues for another page. These
printers are fast (6-8 pages per minute) and a very high resolution (300 - 600 dpi) but are
costliest of all the printers.

 Color Printers: Color printers are the new standard in digital color printing. The complete
family of digital color printers effectively balances low total cost of ownership with high
levels of performance and productivity to directly benefit your bottom line. Compared
with other color laser printers, the new C5000, C7000 and C9000 Series printers employ
our innovative Digital LED and OKI Single Pass Color technologies. These technologies
allow our digital printers to deliver high-speed, high-resolution, high-quality print output,
and unmatched media flexibility, unsurpassed in the industry. Color printers from OKI
Printing Solutions enable you to create high-impact color reports, presentations, mailers,
banners and many other types of printed business communications, without the expense
of using outside commercial printers.
 Dye Sublimation Printers: “Dye-sub” printers were among the first photo-quality color
computer printers, emerging in the early 1990s. Sadly most of the prints made with these

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