Computer Hardware Output Devices Computer Science Essay

When we used computer we have to know the components of the computer. There are two part are very important to operate the computer. It was input and output device. Input device allow us and other systems to send data to the computer. The output devices usually only used to send data from the computer. Although we have many alternatives to send information to other people but we still need output device. We know that output device likes printer are most important hardware in this era.

WHAT IS OUTPUT DEVICES

Output device are computer hardware that allow a computer system to communicate information to a user or another system. This information can be in any form, and includes sound, images, and even tactile experiences. Output devices can usually only be used to send data from the computer; items called input devices allow users and other systems to send data to the computer.

There are four types of output are text, graphics, audio, and video.

Text consists of characters (letters, numbers, punctuation marks, or any other symbol requiring one byte of computer storage space) that are used to create words, sentences, and paragraphs.

Graphics are digital representations of non text information such as drawings, charts, photographs, and animation (a series of still images in rapid sequence that gives the illusion of motion).

Audio is music, speech, or any other sound.

Video consists of images played back at speeds to provide the appearance of full motion.

2.1 PRINTER

A) WHAT IS PRINTER

A printer is an output device that produces text and graphics on a physical medium such as paper or transparency film. Printed information is called hard copy because the information exists physically and is a more permanent from of output. Printers can be grouped in two categories: impact and nonimpact.

Impact printers form characters and graphics by striking a mechanism against an ink ribbon that physically contacts the paper.

A dot-matrix printer is an impact printer that prints images when tiny wire pins on a print head mechanism strike an inked ribbon.

A line printer is an impact printer that prints an entire line at one time. Two popular types of line printers are band printers and shuttle-matrix printers.

Nonimpact printers form characters and graphics without actually striking the paper.

An ink-jet printer is a nonimpact printer that sprays drops of ink onto a piece of paper.

A laser printer is a nonimpact printer that creates images using a laser beam and powdered ink, called toner.

A thermal printer is a nonimpact printer that generates images by pushing electrically heated pins against heat-sensitive paper. Although the print quality of standard thermal printers generally is low, two special types of thermal printers, thermal wax-transfer printers and dye-sublimation printers, have a much higher print quality.

B) THE IMPORTANT OF PRINTER

Printer is hardware that very important because we can save our energy. Before we had this hardware, people using typewriter to type any document and send it to the other person. It make us easy to get the documents on time and we also not wasting our time like typewriter.

ADVANTAGES

The advantages of use printer are:

Save our time, it means we can print a 1000 document in 30 minutes between send it by email. When we send any document by email, it might much long time to do it and also computer sometimes can jammed because too much document.

Save money, and we also can print our material like calendar and card.

Printer likes Inkjet printer is cheaper to buy.

For high volume printing laser printers are considerably cheaper to run.

Printing is fast so they can handle large volumes.

Due to the technology used prints from a laser printer emerge from the printer dry to the touch.

DISADVANTAGES

Although it printer have an advantages but it also have a disadvantage. The disadvantages are;

Waste of Paper a Natural Resource

If we use the old printer it might take longer to print

We cannot print if black out because its using electricity

We had to spend a large amount of money to buy a new ink

Buying a laser printer can be expensive when compared to an inkjet.

Colour laser printers are significantly more expensive than a colour inkjet.

Laser printers are larger and heavier as they need to contain the imaging drum and laser technology.

Due to the cost of ink, running an inkjet printer over time is a more expensive than a laser printer.

Prints emerge from the printer slightly wet and may need time to dry.

Printing is slower and therefore inkjets aren’t designed for high volume printing

2.2 MONITOR

WHAT IS MONITOR

The computer monitor, screen or VDU (visual Display Unit) is the most common output devices. Monitors are display devices external to the computer case and connect via a cable to a port on the video card. Even though the monitor sits outside the main computer housing, it is an essential part of the complete system.

Monitors come in two major types - CRT and LCD. CRT monitors look much like traditional televisions and are very deep in size. LCD monitors are much thinner while still offering equivalent, if not better, graphics quality. LCD monitors are beginning to obsolete CRT monitors due to their smaller “footprint” on the desk and decreasing price.

THE IMPORTANT OF MONITOR

Monitor or also called screen is important because it helps to communicate with the computer. 

ADVANTAGES

Relatively cheap and reliable, can display text and graphics in a wide range of colors.

LCD monitor are more slimmer than CRT monitor and also save spaces.

DISADVANTAGES

No permanent copy to keep and unsuitable for users with visual problems.

Costly when replace parts like the back lighting or even the inverter circuitry

Repair also be costly

2.3 SPEAKERS

In any sound system, ultimate quality depends on the speakers. The best recording, encoded on the most advanced storage device and played by a top-of-the-line deck and amplifier, will sound awful if the system is hooked up to poor speakers. A system’s speaker is the component that takes the electronic signal stored on things like CDS, Tapes, and DVDs and turns it back into actual sound that we can hear.

THE IMPORTANT OF SPEAKERS

ADVANTAGES

Speakers are easy to use

This device also can help a disabilities people otherwise they have difficult to use a computer.

For the business purpose it helps customer give a feedback about their products.

DISADVANTAGES

Sometimes its disturb other people

Disadvantages

· They can take up a fair amount of desk-space, compared to headphones.

· They can distract people around you therefore disrupting a communal work area

 

2.4 PLOTTER

Plotter is device that draws pictures on paper based on commands from computer. It differs from printer in that they draw lines using a pen. As a result, they can produce continuous lines, whereas printer can only simulate lines by printing a closely spaced series of dot. Multicolor plotter use different colored pens to draw different colors.  

The invented of plotter is Hewlett Packard and Tektronix in the late 1970s.In the 1980s, the small and lightweight HP 7470 used an innovative “grit wheel” mechanism which moved only the paper. Modern desktop scanners use a somewhat similar arrangement. These smaller “home-use” plotters became popular for desktop business graphics, but their low speed meant they were not useful for general printing purposes, and another conventional printer would be required for those jobs. One category introduced by Hewlett Packard’s Multiport for the HP 2647 was the “word chart” which used the plotter to draw large letters on a transparency. This was the forerunner of the modern PowerPoint chart. With the widespread availability of high-resolution inkjet and laser printers, inexpensive memory and computers fast enough to rasterizing color images, pen plotters have all but disappeared.

THE IMPORTANT OF PLOTTER

Plotters are often used in science and engineering application for drawing building plans, printer circuit boards and machine parts. They are fast and accurate but relatively expensive compared to printer. They can produce far larger printouts than standard printer, up to the size of a small room

ADVANTAGES

DISADVANTAGES        

2.5 PROJECTOR

WHAT IS PROJECTOR

LCD projectors incorporate a lamp focused onto three small LCD panels. The white light from the projection lamp is split into three colours: red, green and blue. The separated coloured light passes through an individual poly-silicon LCD panel, then combines with the other colours before being focused on the screen. The projected image is created from a matrix of pixels, each of which incorporates a tiny liquid crystal. Colour saturation and intensity are determined by the degree of light allowed to pass through the LCD panel

THE IMPORTANTS OF THE PROJECTOR

Projector is very important because it help people to share their information. For the business purpose, they used it for their presentation or meeting. This device is easy to use because we no need a blackboard to write up our date to present to our boss or lecture.

ADVANTAGES

Easy to carry and set up because projectors are portable for laptop presentations on the move.

DISADVANTAGES

CONCLUSION

The conclusion the overall of important of output device is

FUTURE IMPROVEMENT

In future improvement, I want to see the new technology is created. Now we have a many output device, but it still not working. For example printer, maybe in future we will have a new inverter created the touch printer. We no need to press the button, because its sometimes might can jammed.