Most popular output devices of a computer are the Monitor and printer.
Printer
Printer is an output device that can print data or information on paper.
This printed document is often called as a hard copy.
Printer is connected to the computer either through a USB cable or over Wi-Fi.
Printers are divided into two categories
- Impact printer
- Non impact printer
Impact printer
Impact printer is an output device which works with a ribbon that is stroked against the paper in order to print the character. Different types of impact printers are available.
- Character Printer
- Line printer
Character Printer
Character Printer is an output device used to print the character one at a time. Character Printers are further divided into two main types
- Dot Matrix Printer
- Daisy Wheel Printer
Dot Matrix Printer
- Dot Matrix Printer is an output device that prints the character in the form of a dot pattern.
- Dot Matrix Printer prints uses the print head, that moves up and down or back and forth, and ink soaked ribbon that is stroked against the paper.
- Print head consists of a series of pins that are used to form each character.
- Simple dot matrix printer contains nine pins on its print head. These nine pins are arranged in a 5 x 7 matrix.
- 9 pins and 24 pins are commonly used to print a character.
- Dot Matrix printers is a popular, inexpensive personal computer printer during the 1970 and 1980s.
- Dot Matrix printers can print any shape of a character, special character, image, graphs, etc.
- Quality of printed documents is poor and printed document may even fade away over time.
- printers makes more noise.
- Printing Speed is very slow.
- Despite its disadvantages, Dot Matrix printers are used by some companies for printing bill receipts.
- The first dot matrix printer was created by IBM in the year 1957.
Daisy Wheel Printer
- Daisy Wheel Printer is an output device that works similarly to typewriters.
- Daisy Wheel Printer consists of a disk and a hammer.
- In Daisy Wheel Printer, the disk contains letters, numbers, and symbolic characters.
- Daisy Wheel Printer, the characters mold on the outside edge of each petal on the disk, like a daisy flower.
- While printing using Daisy Wheel Printer, the disk rotates by using a servo motor so that the hammer strikes each
- character against the ink ribbon and impress the character onto the paper.
- In the 1970s, Daisy Wheel Printers were the dominant printers, because they produced quality printing compared to the dot matrix printers.
Line Printer
Line Printer is an output device that prints one line at a time. Line Printers are of two types.
- Drum Printer
- Chain Printer
Drum Printer
Drum Printer is an output device and is one of the oldest line printer.
- Drum Printer consists of a solid, cylindrical drum.
- Drum is divided into a number of print columns. For each print column, there is a band of characters. Drum printer has number of hammers on the front of the drum. Paper is placed between the hammer and ink ribbon. When the esdrum rotates at a high speed, the corresponding hammer behind the paper press the paper against the ink ribbon onto the drum at the right time, so that this printer prints the text on the paper.
- Drum Printer uses the predefined style of the character's font and the picture colors. The meaning is that It doesn't use different fonts and picture colors.
Chain Printer
Chain printer is an output device that uses the horizontally moving chain in which all the print characters are placed.
- The chain moves horizontally around the set of the hammer.
- Like a drum printer, the paper is placed between a series of hammers and an ink ribbon.
- When the desired character is in front of the chain, then the corresponding hammer would press the paper against the ribbon and onto the character in the chain.
- One rotation of the chain is not enough for printing all the characters in a line. Hence, the chain keeps moving until all characters have filled in a line.
- Once the one line has been filled, the page will move to the next line.
Advantages of Chain Printer
- The main advantage of Chain printer is that the type chain can be replaced by the operator when compared to a drum printer.
- The speed of this print is high compared to the drum.
- Chain Printer can easily change the character font.
Disdvantage of Chain Printer
- The main drawback of Chain Printer is that it makes noise and does not print graphics such as tables and charts.
An example of a chain printer is an IBM 1403.
Non-impact Printer
Non-impact type of printer is an output device that prints the character, but it doesn't require to strike the ribbon against the paper.
Non-impact printers can print a whole page at a time. These are further divided into two types
- Inkjet Printer
- Laser Printer
Inkjet Printer
Inkjet printer is a non-impact printer.
- Inkjet printer is an output device that usually prints the text or image by spraying droplets of ink onto the paper.
- The components of this printer can be divided into two major sections such as print head assembly(print head, ink cartridge, print head stepper motor, belt, and stabilizer bar), and paper feed assembly(paper tray, control circuity, paper feed stepper motor, roller, interface port, and power supply).
- The print head has a series of nozzles that are used to drop ink onto the paper.
- Printer Ink is coming from an ink cartridge which is a disposable one.
- Black and color ink cartridges are available in the market.
- In General, the basic four colors are used in the color printer such as CMYB (Cyan, Magenta, Yellow, and Black) colors.
- Printers use the pattern of dots to print a character, just like a dot-matrix printer.
- Printers use very tiny dots that we cannot see them.
- Idea of an inkjet printer was developed in the early 1950s. The first inkjet printer was invented by Ichiro Endo.
- Major manufacturers of an inkjet printer are HP, Canon, Epson, and Brother.
- Inkjet printer of different models are available. Printers range from inexpensive to expensive, in the market.
- Inkjet printer can produce less noise and quality printing.Features of this inkjet printer
- Speed of Inkjet printer is high compared to the dot matrix but slower than the laser printer.
- Produces less noise.
- Suitable for printing in low volume.
- Traditionally Inkjet type of printer is preferred for home use.
- Produce good quality photos.
- Able to print color texts or images.
Laser Printer
Laser printer is an output device and is one of the non impact printers.
- Laser printers use the laser beam or light to print the text or image onto the paper.
- Laser printer consists of different small components such as cylindrical drum (also known as photo-conductor), toner cartridge, transfer belt, fuse unit, and mirror.
- Main concept of Laser printer involves the following steps:
- first to use laser beam to draw the text or image onto the cylindrical drum
- then those areas are attracted with toner powder and
- transfer toner powder onto the paper by using heat
- melt toner powder to create the text or image onto the paper.
- First laser printer was invented on 1969 by Gray Starkweather who was working in the Xerox product development team.
- The laser printer were mainly built for office use.
- For economical reason, it would be used as a home printer.
- This printer is suitable for printing large volume of documents.
- Laser printers are costlier than inkjet printers.
- Different kinds of laser printers are available such as color laser printer and Monochrome laser printer (prints the text in black and white).
Features of the laser printer
- Speed of this printer is high.
- Produce high-quality printing.
- Very expensive compared to others, such as dot-matrix or inkjet printer.
- Suitable for printing a high volume of papers.
- It doesn't produce more noise