What is printer | Types of printers

What is printer?

A printer is an output device that prints text document, images and a combination of both. There are many types of printer according to their printing quality, printing technique and so on.

Types of of printer according to printing technique

1. Impact printer

An impact printer is a type of printer that forms characters or images by striking mechanism such as a print hammer or wheel against an inked ribbon, leaving an image on paper. A dot-matrix printer contains a print head of small pins that strike an inked ribbon, forming characters or images. Print heads are available with 9, 18, or 24 pins; the 24-pin head offers the best print quality.

Example of Impact printer : Dot matrix printer, golf-ball printer, drum printer, daisy wheel printer etc.

2. Non-Impact printer

In non-impact printer there is no physical contact between paper or ribbon.

Example of non-impact printer : Laser printer, thermal printer, ink jet printer etc.

Types of printer according to printing sequence

1. Serial or character printer

In a serial or character printer characters are printed one after the other in a sequence manner. Therefore, only one character is printed at a time.

Examples are daisy wheel printer and dot matrix printer.

2. Parallel or line printer

In a line printer, many lines are printed at a time.  Line printers, or line-at-a-time printers, use special mechanism that can print a whole line at once; they can typically print in the range of 1,200 to 6,000 lines per minute.

Examples are drum, chain, and band printers.

Speed of line printer is higher than character printer as it prints multiple lines at a time. Speed of line printer is specified in LPM (line per minute) or PPM (page per minute).

Types of printer according to print quality

1. Draft printer

In a draft printer, character is formed by closely spaced dots. And these closely spaced dots looks like an character. In a draft printer, there is a lack of visibility of characters due to the presence of dots.

Example : dot matrix printer

2. Letter quality printer (LQP)

In a letter quality printer, character is formed as letter like a typewriter. In a letter quality printer, characters are impressive  because there is no dots.

Example : daisy wheel printer

3. Near letter quality printer (NLQ)

In a near letter quality printer, character is formed by closely spaced dots. But each character is printed twice. Hence dots are offset by a minute distance. In NLQ characters are more impressive than draft quality printer.

Types of printer according to print mechanism

1. Dot matrix printer

In dot matrix printer, character is formed by small dots. Dot matrix printers, also known as impact matrix devices, are an older kind of printer that relies on an ink-soaked ribbon similar to that used in a typewriter. Dot matrix printer was the most common inexpensive printing option during the 1970s and 1980s, but were largely replaced by laser and inkjet models by the mid-1990s. However, as of the date of publication, dot matrix printers are still in use for some specialty applications, due to their ability to print quickly even on multi-part documents.

2. Daisy wheel printer

A daisy wheel printer is an impact printer invented in in 1969 by David S. Lee at Diablo Data Systems. In daisy wheel printer, print head consists of a circular wheel. This print head carries 96 spokes or character arm on wheel. Each spokes has a print bock. To print an character the wheel is rotated until the petal carrying the desired character is in front of the print space on the paper. Then hammer strike each character into an ink ribbon to create the character on paper.

3. Golf ball printer

In golf ball printer, there is a spherical golf ball like metallic unit. Many characters are present on this golf ball. To print an character drive mechanism causes appropriate movement of the ball, then the character to be printed is brought in front on the desired position of the paper. Then ball is pushed on the paper and character is printed.