Output devices

Output device
The output unit is used for displaying or printing the process the data in a user readable form a computer can have several output devices attached to it. Some of the common output devices are listed below
Monitor
Monitor is the most common output device is also called visual display unit, an electronic visual display unit or electronic visual display for computers just like a television monitor also display the output on the screen. The output displayed on the monitor is called soft copy.

The most of common types of monitors are given below

1. (CRT) cathode ray tube monitors
2.(LCD) liquid crystal display

1. Cathode ray tube monitors
CRT monitors were the most common monitors until flat panel screen became of a double they consist of an electronic gun in this monitors a beam of electrons light up the pixels /phosphor dots which forms the inner coating of the screen. CRT monitors are bulky and occupy a lot of space they are available in various ages like 14 inches 15 inches, 17 inches and 21 inches.A CRT monitors still has better contrast ratio and viewing angles then any other type of computer monitor.

2. Liquid crystal display monitors

LCD monitors are relative Lee Min and lighter than CRT monitors they use light model modulating properties of liquid crystals. They provide a wide viewing angle and come in various sizes ranging from 17 inches to 60 inches. The display sharp images and require less power to run and they also used in device such as watches, radio players, calculator, gaming devices and telephones.

Touch screen monitor

Touch screen is a special monitor that allows the user to input information by touching the icons are graphical buttons present on the screen one can enter only a limited amount of data by using touching screen Technology. It is also used ATM machines, office and cineplexes to retrive desert information.

Printers

A printer is a very parallel device used for printing the output on a paper or any other printable media. which is called a hard copy printers are two types they are given below

1. Impact printer

2. Non impact printer

1. Impact printers

Impact printers allow physical contact between the printer head and paper that is they print by the impact of dot virus on the paper they also called character printers.

Impact printers are classified as follows:

Daisy wheel printers : this printer have good letter formation capability but cannot produce graphics, they produce letter quality documents.

Dot Matrix printers: Dot Matrix printers are the only impact printers in used nowadays they are noisy and do not have good printing quality as a result, they are losing popularity.

2. Non impact printers

Non impact printers do not allow physical contact between the printing heads and the paper they do not strike against the ink Ribbon or the paper which is being printed.
In the addition, they can also produced colour graphics the non impact printers are categorised thermal inkjet and laser printer.

Thermal printers: thermal printers use special heat sensitive paper characters are formed when heated element come in contact with the heat sensitive paper does forming darken dots.

Inkjet printers: they produce images by spraying tiny droplets of pink into the paper they have very high quality output and can also produced colour red graphics this printers all Plus mysy the average quality of inkjet printers is 300 DPI dots per inch all the few latest model offer higher resolution.

Laser printers: this printers used photocopy technology to print laser printers used laser beam and dry powder ink to produce a fine Dot Matrix pattern the quality of output on paper is very good they can also produce very high quality images they are mostly for DTP stands for desktop publishing papers.

Speakers

Speakers at the output device which are used to play sound speaker convert an alternating electrical current into sound too maybe built into the system unit are connected with cables we can listen to music and various sound effects through them.

Plotters
A plotter is a vector graphics printing device which is used to print graphical plots on the paper or polyester films plotters are different type from printers they are generally vector-based and draw lines using a pen they are two types of plotters we have flatbed plotter and drum plotter.