Understand Output Devices Before You Regret

Understand Output Devices Before You Regret-Two-way communication is only possible when we send data and receive information. We provide data to a computer through input devices. After the computer has processed the data, we need to see the results. Information processed by the system is called output. Output devices are hardware devices that present output to users in human-readable form.

The monitor

The monitor is the most common and the most important output device. It is also called a visual display unit. The output viewed on a monitor is called soft copy. There are two basic types of monitors: CRT monitors and LCD monitors.

The CRT monitor (CRT full form)

CRT full form is Cathode Ray Tube. CRT monitors are older types of monitors. They are curved and bulky.

The LCD monitor (LCD full form)

LCD full form is Liquid Crystal Display. LCD monitors are more advanced. They are smaller and thinner than CRT monitors. They provide a flat image and do not flicker. They need less electric current and can display more colours. They are used in laptops and in desktop computers. The advantage of using LCDs with laptops is that they consume less energy and can work on batteries.

The plasma screen

Plasma screens are bright screens that can be produced in large sizes (up to 84 inches). They are used in televisions and are more expensive than CRTs and LCDs.

The screen of the monitor can be divided into small dots called pixels. The more the pixels used to make up an image, the higher the screen resolution. Resolution can be high, medium, or low. High-resolution images are clearer than low-resolution images.

The e-book reader

An e-book (electronic book) reader is a hand-held, book-sized device that displays text and graphics. E-book readers are used to read newspapers, magazines, and books. Most of the material is downloaded from the Internet. One e-book can store material contained in several traditional books.

The data projector

A data projector projects output on a large screen or wall. The output looks just like it would appear on a traditional monitor, but it is much larger. Data projectors are used to give presentations in classrooms and offices. The advantage of such output devices is that the speaker can easily address a much larger audience.

High-definition television (HDTV full form)

HDTV full form is “High-definition television” applies microcomputer technology to television. It is also called PC/TV. HDTV gives a clearer and more detailed wide-screen picture than ordinary N. With HDTV, we can freeze video images to create positive still images. The video and images can be edited, digitized, and stored on disk. Designers and artists use HDTV.

The printer

Related article: 28 Great Lessons You Can Learn From Input Devices.

A printer is an output device used to print text and images on paper or other media. Such output is called hard copy. Different types of printers are available. Their selection depends on the application they will be used for. Their initial and running costs also play a major role in the final decision.

The laser printer

The laser printer can print large quantities at a great speed. It is also called a page printer because it prints a complete page at a time. Laser printers used by single users are called personal laser printers. They are inexpensive but can print only four to six pages a minute. Shared laser printers are used in offices. They are expensive but can print more than 30 pages a minute.

Some laser printers are monochrome, while others print in colour. Some laser printers can be combined with a fax machine, a photocopier, and a scanner. Laser printers produce positive output and work silently. Some can even print on both sides of a paper. They are also quite large and expensive.

The thermal printer

A thermal printer is a printer that uses heat to burn an image onto specially-treated paper. Thermal printers are used at some POS terminals. Some thermal printers can also produce positive coloured artwork and text.

The ink-jet printer

An ink-jet printer prints text and images by spraying ink of different colours at a high speed. The speed is measured in pages per minute (ppm). Ink-jet printers produce hard copies of images that have been created using digital cameras.

They can be used wherever colour and appearance are important, like in advertising. Ink-jet printers are inexpensive, reliable, light, and easy to operate. They are slow and do not produce as high a quality as laser printers. Some types of printers are not used nowadays.

The dot-matrix printer

A dot-matrix printer prints characters and images by using a series of small pins on a print head. The paper is positioned on the other side of an ink-coated ribbon. As the print head strikes the ribbon, it leaves an inked impression of the character on the paper. The dot-matrix printer is inexpensive and reliable. But it is noisy and produces poor-quality output. It prints on a reel of paper and is used at POS terminals for printing receipts. It is also called a character printer because it prints one character at a time.

Other printers not used any more are the daisy-wheel printer, drum printer, and chain printer. The daisy-wheel printer is also a character printer. But the drum printer and chain printer are called line printers because they print one complete line at a time.

The plotter

A plotter is a special printer that produces high quality output using pens. Plotters create large-sized, multicoloured documents like maps and engineering drawings.

The speaker

A speaker transmits output in the form of sound. A sound card installed on a computer produces positive sound for music and games. A recent development in sound output is speech synthesis. A speech synthesizer can artificially produce the human voice. It can be used to read documents to visually-impaired people. It can .be used to teach a child to spell through educational games. It can also issue spoken warnings. Some cars use voiced warnings to warn passengers who have not fastened their seat belts. Some devices combine input and output devices to save time.

Facsimile transmission: The fax machine

A fax machine sends and receives messages over telephone lines. It uses regular telephone lines to send copies of documents which may include drawings as well as text. A fax/modem board connects the computer with telephone lines. A document is inserted into the fax machine and the number of the recipient is dialled. The machine scans the document and transmits it over telephone lines to a fax machine at the receiving end. The receiving fax machine prints the document or displays it on a monitor.

Internet telephony

Internet telephony uses the Internet instead of telephone lines to connect two or more people via telephone. Long distance telephone calls can be made cheaply. A microphone and headset/speakers are connected to the computers at the two ends. This can be used like a telephone receiver to have conversations.

Multi functional devices

Multi functional devices combine the capabilities of a scanner, fax machine, printer, and a photocopier. These devices save space and are used in offices. However, the quality of output is poorer than that produced by separate, single-purpose devices.

Summary : Conclusion

• Output devices are hardware devices that present output to users.
• The monitor is the most common output device. It.is also called a visual display unit.
• CRT monitors are older types of monitors. They are curved and bulky.
• LCD monitors are smaller and thinner than CRT monitors. They provide a flat image and do not flicker.
• Plasma screens are bright screens that can be produced in large sizes. They are used in televisions and are more expensive than CRTs and LCDs.
• The screen of the monitor can be divided into small dots called pixels. The more the pixels used to make up an image, the higher the resolution.
• An e-book reader is a hand-held, book-sized device that ‘displays text – and graphics, mostly from Internet.
• A data projector projects output on a large screen or wall.
• High-definition television applies microcomputer technology to television. HDTV gives a clearer wide-screen picture than ordinary TV.
• A printer prints text and images on paper or other media. Such output is called hard copy.
• A laser printer can print large quantities at a great speed.
• A thermal printer uses heat to burn an image onto specially-treated paper.
•  An ink-jet printer produces hard copy by spraying ink of different colours at a high speed.
• A dot-matrix printer prints characters and images with a series of small pins on a print-head.
• Dot-matrix printers and daisy-wheel printers are called character printers.
• Drum printers and chain printers print one complete line at a time.
• A plotter is a special printer that produces positive output using pens.
•  A speaker transmits output in the form of sound.
• A speech synthesizer can artificially produce the human voice.
•  A fax machine sends and receives messages over telephone lines.
• Internet telephony uses the Internet to connect people via telephone.
• Multi functional devices combine the capabilities of a scanner, fax machine, printer, and a photocopier.