Printer is an output device which prints the result on paper. The copy of this result on paper is called hard copy. The information obtained by computer is saved on printer memory because printer does not work fast as information obtains by computer.
In other words we can say that printer is an output device which converts softcopy to hard copy. There are different types of printer which re below:
1. Impact Printers
2. Non Impacts Printers
Impact Printers: Impact Printers are the printers that create output on paper by using a device to beat a linked ribbon, burning ink from the ribbon onto the paper. The process of impact printer is similar to type writer which has hammer of metal or print head.
There are different type impact printers which are:
1. Character Printer
2. Line Printer
Character Printer: These printers print single character at a time. It is slow printer and divided into daisy wheel and dot matrix printer.
1. Daisy Wheel Printers: Daisy wheel printers print the characters by using metal hub and spokes in these spokes characters are printed when these spokes impacting on ribbon and paper this is called daisy wheel device. It provides high resolution result comparison as dot matrix so it is called letter quality printer. It runs in horizontal direction. This type printer is slow.
2. Dot Matrix printers: Dot matrix printer is also impact printer which is very soft at printing time. It has lots of pins at printer head. It print a dot by attach ribbon of each pin on paper. Joining lot of dot make a character. It has a vertical group of pins in printer head.
Line Printer: Line printer is also impact printer which prints one line at a time. Line printer has high speed comparison as character printer. It prints 300 to 3000 lines per minute. These printers are used for huge work in mini and main frame computer. There are two types of line printer which are:
1. Drum Printers: These printer prints the line by a rotating drum having a ring of characters for every print positions, the hammers collision every character of the drum at the same time.
2. Chain Printers: Chain printer prints the line by rotating chain having ring characters for every print place. Really the working device of this print like to the drum printer.
Non Impact Printer: It provides the output on the page without the printer head touching the paper. This is done by different way to place ink on the paper without really striking with the paper. The quality of this type printer is high comparison as impact printer. It has high speed as impact printer. There are various types of non impact printer which are below:
1. Laser Printer
2. Inkjet Printer
Laser Printer: Laser printer is a non impact printer which is used in computer system from 1970. Before these computers are used in mainframe computer. Today these types of computers are very favorite because these provide print with high quality text and graphics. These printers have very fast speed for printing the paper.
An extra micro processor RAM and ROM is used in mostly laser printer. In this printer dot are very near each other by which it provides best printing. Cart Raze is used in this printer in which dry ink is filled. The working process of laser printer is similar to photo copy machine but very fast light is used in its. Laser printer prints 300-600 dot/inch. It has special types of toner in which the particle of different colour are filled. It can provide printing result on plastic sheet.
Merits of Laser Printers:
1. High resolution
2. Capable for lots of quantity printing
3. Less cost per page printing
Demerits of Laser Printers:
1. It is big and heavy from inkjet printers.
2. It is costly from inkjet printers
3. Changing of the toner and drum are very costly.
Inkjet printer is also a non impact printer which provides the output by spraying tiny droplets of ink on to the paper. The output of inkjet printer is very clear. The joining of lots of dot creates characters. There are four nozzle in colour ink jet printer like black, yellow, red and blue. This type printer is known as CMYK printer. Mixture these four colour we make any colour according as requirement. It prints 40-300 character per sec. The average life of an inkjet print head is about 10 billion characters which is 5 times more than an impact type dot matrix printer.