What is a Printer? | Impact and Non-impact Printers | BCA | SparkEasy

For example, if we have to submit any project report to a company, we need to create a soft copy of our report with the help of a printer. Printers vary in size, speed, and cost. Generally, for high-resolution color printing, costlier printers are used.

There are mainly two categories of printers: impact and non-impact printers. Depending upon the printing methods and image quality produced after printing, printers are of two major types:-

1. Impact Printers

These printers usually work with paper via direct contact with an ink ribbon. It has similar mechanisms to a typewriter. Examples: Drum Printers, Dot-Matrix Printers, Chain/band Printers.

2. Non-Impact Printers

Non-Impact Printers do not need to touch the ink ribbon to print the documents. Maintenance of Non-Impact printers is relatively easier than Impact printers. Examples: Inkjet printers and Laser Printers.

Dot-Matrix Printers

Dot-Matrix printers are character printers that print one character at a time. They form characters and all kinds of images as patterns of dots.

This printer has a print head that moves horizontally ( left to right and right to left) across the paper. The print head contains an array of pins. The printer can activate each pin independent of others to extend and strike against an inked ribbon to form a dot on the paper. In order to print a character, the printer activates the appropriate set of pins as the print head moves horizontally.

For faster printing, many dot-matrix printers print both ways- while the print head moves from left to right and while it moves from right to left, on return. Such a method is called bi-directional printing.

Since dot-matrix printers produce printed output as patterns of dots, they can print any shape of character that a program can describe. They, therefore, can print many unique characters, different sizes of print, and graphics such as charts and graphs.

Dot-matrix printers are impact printers because they print by hammering pins on an inked ribbon to leave an ink impression on a paper. Hence, we can use them for producing multiple copies by using carbon paper or its equivalent. Due to impact printing, dot-matrix printers are noisy compared to non-impact printers.

Usually, dot-matrix printers are slow, having printing speeds of 30 to 600 characters per second. However, they are cheap in terms of both initial cost and cost of operation. Hence, individuals and organizations prefer them for generating hard copy output if printing speed and quality are not significant factors.

Inkjet Printers

Inkjet printers are character printers that form characters and images by spraying tiny drops of ink on paper. The print head of an inkjet printer contains up to 64 tiny nozzles.

The printer can heat the nozzle selectively in a few microseconds by an integrated circuit resistor. When the resistor hits up, the ink vaporizes and ejects through the nozzle making dots on the paper in front of the print head. In order to print a character, the printer selectively heats the appropriate set of nozzles as the print head moves horizontally.

Inkjet printers produce higher quality output than dot-matrix printers because they form characters with tiny ink dots. A high-resolution inkjet printer has as many as 64 nozzles within a height of 7mm, providing a print resolution of around 360 dots per inch.

Since inkjet printers produce printed output as patterns of tiny dots, they can print any shape of characters that a program can describe. These nozzles allow printers to print many unique characters, different print sizes, and graphics such as charts and graphs.

Inkjet printers are non-impact printers because they print by spraying ink on paper. Hence, they are quieter in operation, but we cannot use them to produce multiple document copies in a single printing.

Inkjet printers are both monochrome and color. A monochrome inkjet printer uses a single cartridge with black ink, whereas a color inkjet printer uses two ink cartridges- black and tri-color. The tri-color cartridge contains red, blue, and green colors in a package that can mix an appropriate amount of these colors with black from the other cartridge to get any desired color. Hence, inkjet printers can produce multi-colored and photo-quality output.

Inkjet printers are slower than dot-matrix printers are, with printing speeds ranging from 40 to 300 characters per second. They are costlier than dot-matrix printers. Users prefer them for better quality output if the speed of printing is not an essential factor.

Drum Printers

Drum printers are line printers that print an entire line at a time. Recall that dot-matrix and inkjet printers print one character at a time.

Hence, a drum printer with 132 characters per line and supporting a character set of 96 characters will have altogether 12,672 (132 x 96) characters embossed on its surface.

In drum printers, it consists of hammers in front of the drum. While printing, we place an inked ribbon and paper between the hammer and the drum. The total number of hammers equals the number of bands on the drum and the total print positions per line.

The drum rotates at a higher speed. So, to print a character at the desired print position, the printer activates the appropriate hammer when the character embossed on the band at the print position passes below it. Hence, the drum would have to complete one full revolution to print each output line. It means that the printer does not print all characters on a line at precisely the same time, but the time required to print an entire line is so fast that it appears to print one line at a time.

The drum of a drum printer is expensive, and we cannot change it often. Hence, the drum printers can print a pre-defined set of characters only in a pre-defined style embossed on the drum. Drum printers, therefore, cannot print any shape of the character, different sizes of print, and graphics such as charts and graphs.

Drum printers are impact printers because they print by hammering on paper and inked ribbon against characters embossed on the drum. Hence, we can use them for producing multiple copies by using carbon paper or its equivalent. Due to impact printing, drum printers are noisy and often use a cover to reduce noise. Printing speeds of drum printers are in the range of 300 to 2000 lines per minute.

Chain/Band Printers

Chain/band printers are line printers that print one line at a time. It consists of a metallic chain/band on which all characters of the character set supported by the printer are embossed. A standard character set may have 48, 64, or 96 characters. So, to enhance printing speed, these printers have several sets of embossed characters in character set on the chain/ band.

The printer has a set of hammers mounted in front of the chain/band so that we can place an inked ribbon and paper between the hammers and chain/band. The total number of hammers equals the total number of print positions. Therefore, a printer supporting 132 print positions will have 132 hammers.

The chain/band rotates at high speed. In order to print a character at the desired print position, the printer activates the appropriate hammer when the character embossed on the chain/band passes below it. Since the character set appears several times on the chain/band, it is unnecessary to wait for the chain/band to make a complete revolution to position the desired character in the correct print position.

Unlike the drum of a drum printer, we can change the chain/band of a chain/band printer easily. It allows the use of different fonts and different scripts with the same printer. Like drum printers, chain/band printers can print only pre-defined sets of characters embossed on the chain/band used with the printer.

Chain/band printers, therefore, cannot print any shape of characters, different sizes of print, and graphics such as charts and graphs.

Chain/band printers are impact printers because they print by hammering on a paper and inked ribbon against characters embossed on the chain/band. Hence, they enable the production of multiple copies using carbon paper or its equivalent. Due to impact printing, chain/band printers are noisy and often use a cover to reduce noise. The printing speed of chain/band printers is 400 to 3000 lines per minute.

Laser Printers

Laser printers are page printers that print one page at a time. The main components of a laser printer are a laser beam source, multi-sided mirror, photo-conductive drum, and toner (tiny particles of oppositely charged ink).

Laser printers produce high-quality output because they form characters by tiny ink particles. The most common laser printers have a resolution of 600 dpi ( dot per inch), whereas some high-end printers have a resolution of 1200 dpi. Due to their high resolution, these printers give excellent graphics and art quality.

Since laser printers produce printed output as patterns generated by the laser beam, they can print any shape of characters that a program can describe. They, therefore, can print many unique characters, different sizes of print, and graphics such as charts and graphs.

Laser printers are non-impact printers. Hence, they are pretty in operation, but we cannot use them to produce multiple document copies in a single printing.

Although most laser printers can print in black color only because they have a single toner-drum arrangement, now color laser printers are also available at an affordable price. A color laser printer has four-color toners, each with a drum. It uses the drums and toners in the same manner as described above but charges each drum together to produce the desired color output.

Due to print quality, speed, and technological advances, it has become increasingly popular. The airline, banking, entertainment, retail, grocery, and healthcare industries use these printers. They are also quite popular in creating labels owing to the printing speed.