Chapter 6 - Printers

Abstract

While the information one's computer holds may be phenomenal, one must communicate it to one's clients through the printer. If that printer is unable to produce a professional result or is physically incapable of meeting one's business needs either in terms of its versatility or in terms of reliability, everything one has done on the computer will have been for naught. There are currently three major technologies used in today's printers: dot matrix technology, ink-jet technology, and laser technology. Dot matrix printers are the oldest and least expensive of today's choices. Dot matrix printers operate by using pins to strike a ribbon to the paper. Multiple strikes of the ribbon produce dots, which combined, approximate letters, and symbols. Ink-jet printers operate much like the dot-matrix printer, substituting multiple ink nozzles for the pins found on the dot matrix printer. Laser printers operate similarly to that of the copy machine. A laser beam is rapidly pulsed off a rotating mirror into the toner cartridge. The toner cartridge contains a drum coated with light sensitive material. The laser beam generates a static charge to each area it contacts the drum. As the drum rotates, the statically charged material retains toner, which in turn is passed to the paper fed through the printer. The paper, which also contains a static charge, retains the toner as the drum rotates past it. The drum is then cleaned and the remaining static charge dissipated by a discharge wire in its path. The paper now contains printing via the toner transmitted onto it by the drum. It is then passed through fusing rollers, which use heat and pressure to fuse the toner to the paper.