Download
1 / 29
520 likes | 893 Vues
PRINTERS. Outline. Introduction. Printer is an output device attached to your computer that produces printed copies on paper (hard copies). Connecting printer to a PC. Printer Can be connected through parallel port which is on the back of CPU.
E N D
Introduction • Printer is an output device attached to your computer that produces printed copies on paper (hard copies).
Connecting printer to a PC • Printer Can be connected through parallel port which is on the back of CPU. • Now a days printers can be connected by the USB which is more compact and reliable. • Network interface allows several computers to share one printer. There are also Wi-Fi printers that are available through a wireless network
Impact Printer • Impact Printers use a print head containing a number of metal pins which strike an inked ribbon placed between the print head and the paper. • Dot-matrix printers, Daisy wheel printers, etc.
Non Impact Printer • Non-impact printers are much quieter than impact printers as their printing heads do not strike the paper. • Several different technologies have been used to provide a variety of printers. • Laser printers, Bubble-jet printers etc.
Dot Matrix Printer • Commonly used for printing invoices, purchase orders, labels etc. • As the printer head moves in horizontal direction • The printhead controller sends electrical signals • Forces the appropriate wires to strike against the inked ribbon, making dots on the paper and forming the desired characters.
Advantages and Disadvantages Advantages Disadvantages Impact printers are usually noisy They can only print low resolution graphics, with limited color performance, limited quality and comparatively low speed. • Can print on multi-part stationery or make carbon-copies. • One of the lowest printing costs per page. • They are able to use continuous paper rather than requiring individual sheets, making them useful for data logging. • They are good, reliable workhorses ideal for use in situations where printed content is more important than quality. • The ink ribbon also does not easily dry out,.
Daisy Wheel Printers • A daisy-wheel printer works on the same principle as a ball-head typewriter. • The daisy wheel is a disk made of plastic or metal on which characters stand out in relief along the outer edge.
To print a character, the printer rotates the disk until the desired letter is facing the paper. • Then a hammer strikes the disk, forcing the character to hit an ink ribbon. • Change the daisy wheel to print different fonts.
INKJET printers and BUBBLEJET printers • The inkjet printer technology was originally invented by Canon • Today's printer heads are made up of several nozzles (up to 256), equivalent to several syringes, which are heated up to between 300 and 400°C several times per second. • Each nozzle produces a tiny bubble that ejects an extremely fine droplet. • The vacuum caused by the decrease in pressure creates a new bubble.
Generally, we make a distinction between the two different technologies: • Inkjet printers • use nozzles that have their own built-in heating element. Thermal technology is used here. • Bubble jet printers • use nozzles that have piezoelectric technology. Each nozzle works with a piezoelectric crystal that changes shape when excited by its resonance frequency and ejects an ink bubble.
Laser printer • The laser printer produce quality print-outs at a high print speed. • Mostly used in professional and semi-professional settings because of their high cost. • Technology that is close to that used by photocopiers. • Mainly made up of an elecrostatically charge photosensitive drum that attracts the ink in order to make a shape that will be deposited on the sheet of paper.
Laser technology • a primary charge roller gives the sheets of paper a positive charge. • The laser gives a positive charge to certain spots on the drum with a pivoting mirror. • Then, negatively charged ink in powder form (toner) is deposited on the parts of the drum that were previously charged by the laser.
By turning, the drum deposits the ink on the paper. A heating wire (called a corona wire) finally attaches the ink to the paper.
Advantages and disadvantages Advantages Disadvantages Buying a laser printer can be expensive when compared to an inkjet. Colour laser printers are significantly more expensive than a colour inkjet. Laser printers are larger and heavier as they need to contain the imaging drum and laser technology. • Laser prints are generally very high and very accurate. • For high volume printing laser printers are considerably cheaper to run. • Printing is fast so they can handle large volumes. • Due to the technology used prints from a laser printer emerge from the printer dry to the touch.
Thermal printers • Uses a thin plastic ribbon with a thin coating of wax or resin based pigment. • The ribbon and labels feed from separate rolls and are squeezed together by a roller as they pass under the thermal printhead . • The heating elements in the printhead melt the coating which transfers to the label to form the image.
Produces a durable, high-quality image, • Can be used with many types of label stocks (paper and synthetics). • Durable and offer relatively fast printing speeds; some models approach 12 inches per second.
Future technologies • HP offers future printing technologies Printer makes 2,600 pages per minute introducing a new ink-jet printer that prints thousands of pages per minute and ink that retains its shine even when exposed to extreme elements.
Xerox • Xerox is developing a new printing technology which does not require ink of any kind. The new technology includes reusable paper which can be printed and erased dozens of times .
Memjet technology • Memjet technology is a patented breakthrough in print engine components that delivers the benefits of ink and laser technologies at radically new price/performance levels. • Memjet technology is comprised of four tightly integrated components: page-width printheads, driver chips, ink and software. • Customized water-based inks ensure great print quality whether printing photos, office documents or industrial labels
