Different Types of Printer

Published: 09th December 2011
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Printer is a hardware output device used to produce a hard copy of a text or image oriented document. Printers are available in color or black & white. Printer resolution has improved greatly over the years as costs have continued to fall. Among the printer types available are the daisy wheel, where the actual printing mechanism is similar to the IBM electric typewriter with its ball and wheel paper striking device; the dot matrix; the ink jet; the laser printer, designed for high resolution, the high-speed line printer that produces low quality output; the LCD and LED, both high resolution devices and the thermal printer such as might be found with older copy or fax machines. Some printers, such as the line and daisy wheel, are capable of producing text-only documents. Hewlett Packard, Cannon, and Epson are among the many companies manufacturing low-cost, high-speed quality printers capable of many functions.

A printer produces output in text as well as graphics on a paper. Before getting into details about the types of printers, one must has an idea of the print quality, an important feature of hard copy devices.

Typeset Quality: These kinds of prints are mostly being used in magazines or text books in the shape of letters and characters fully formed, using solid lines.

Near-typeset Quality: this print is similar in quality to that produced by a type-set machine, such as print found in magazines.

Letter Quality: this print is made using fully formed characters, as opposed to characters made up of series of lines.

Near-letter Quality: it is a printing mode by head passing on the same line multiple times.

Standard Quality: it is produced when characters composed of dots or lines are formed by a single pass of the print head.

Draft Quality: the characters are formed with a minimum number of dots or lines and are smaller than the standard quality characters.

Impact Printers

These printers produce prints by hammering or pin striking on the ink ribbon, which leaves an impression of the print on the paper. These printers are also divided into;

Character-at-a-time Printers

The mechanism of there printers are similar to ordinary typewriters. The speed of these printers is measured in characters per second (CPS). These printers are;

1. Daisy Wheel Printers

These printers are used to get the quality of type found on typewriters. The daisy printers are so called because the print mechanism looks like a daisy. These printers give letter quality print but are slow typically 25-55 characters per second.

2. Dot -Matrix Printers

These printers use heads containing nine to twenty four pins. These pins produce patterns of dots on the paper to form the individual characters. The printing cost of these printers is less expensive than others and they typically print at speed of 100-600 characters per second. These printers can give draft quality, standard quality and near-letter quality prints.

Line-at-a-time Printers

These printers have a special mechanism that prints a whole line at once. These printers can typically print in the range of 400 letters per minute (LPM) to 8000 letters per minute (LPM). They are normally 132 column printers, having 132 printing heads. These printers can be of following types;

1. Drum Printers

These printers have a complete character set engraved around the circumference of each print position of the drum. The number of print positions across the drum equals the number of characters in a line available on a page. One complete round is required to print a whole line.

2. Chain Printers

Chain printers use a chain of print characters wrapped around two pulleys. Like the drum printer, a chain printer has one hammer for each print position. The chain rotates until all of the required print positions on the line have been filled. Then, the page moves up to print the next line.

3.Band Printers

Band printers operate the same way as chain printers. However, they use a steel band instead of a chain and has fewer hammers. 'impact printers. These printers are categorized into the following kinds based on they technology they use.

4. Ink-jet Printers

These printers have tiny nozzles that spray charged ink particles. These particles are passed through an electrical field that arranges the charged ink droplets into characters. The ink is absorbed into the paper and dries instantly. These printers produce quality output at the speed of 300 characters per second.

5. Thermal-Transfer

These printers use heat to transfer ink on paper. Thermal printers produce near letter quality prints. They bond ink onto the paper by heating pins that press against a special wax-inked ribbon. Thermal wax printers produce color images by melting color wax onto paper. These printers are twice as fast as ink-jet printers and are used for animation and graphic arts applications. Some thermal printers use special heat sensitive paper, which turned black at the places where the hot pins strike. Fax machine is the example of this type of thermal printer.

6. Dye-Diffusion Printers

Dye-diffusion printers produce the images by heating the ribbon to vaporize the dye and diffusion paper. They are expensive, and used for photography for quality images. They can produce millions of different color shades.

7. Electrostatic Printer

These printers are fast, high-resolution printers, used where complex images are needed. Such as mapping integrated circuit design, satellite imaging, and remote sensing. These printers are very expensive.

8. Laser Printers

Laser printers are used where the best quality output is the main consideration. These printers produce high-quality text and graphics. In order to produce a print, a laser beam is directed at a mirror that bounces the beam onto a drum, leaving negative charge on the drum. Then, positively charged toner (ink) sticks to the drum. The drum rolls on the paper, the ink is transferred to the paper.


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Rashid javed writes articles about computer basics such as concept of connectivity and basics of computer

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