Computers Are Your Future © 2005 Prentice-Hall, Inc. CXC IT Unit 1 Objective 6 OUTPUT DEVICES Output – getting data out!

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 2 What You Will Learn About What is output? What are output devices? What are output medias? What are examples of output devices and how are they used?

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 3 Output Devices: Engaging our Senses Output devices are peripheral devices that enable us to view or hear the computer’s processed data.  Visual output – Text, graphics, and video  Audio output – Sounds, music, and synthesized speech

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 4 Monitors A monitor is a peripheral device which displays computer output on a screen. Screen output is referred to as soft copy. Types of monitors:  Cathode-ray tube (CRT) Cathode-ray tube (CRT)  Liquid Crystal Display (LCD or flat-panel) Liquid Crystal Display (LCD or flat-panel) CRT LCD

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 5 Cathode-ray tube (CRT) Resemble televisions Use picture tube technology Less expensive than a LCD monitor Take up more desk space and use more energy than LCD monitors

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 6 Liquid Crystal Display (LCD) Cells sandwiched between two transparent layers form images Used for notebook computers, PDAs, cellular phones, and personal computers More expensive than a CRT monitor Take up less desk space and use less energy than CRT monitors Types of LCD monitors:  Passive-matrix LCD  Active-matrix LCD  Gas plasma display  Field emission display

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 7 Monitor Specifications Screen size – The diagonal measurement of the screen surface in inches (15, 17, 19, 21) Resolution – The sharpness of the image determined by the number of horizontal and vertical dots (pixels) that the screen can display (800 x 600, 1024 x 768, 1600 x 1200) Refresh rate – The speed at which the screen is redrawn (refreshed) and measured in Hertz (Hz) (60Hz, 75Hz)

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 8 Televisions as Monitors Televisions have low resolution; therefore, they produce poor quality computer output. An NTSC (National Television Standards Committee) converter is needed to connect a computer to a TV. High Definition Television (HDTV) is designed to use digital signals. Digital TVs enable interactive use.

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 9 Printers A printer is a peripheral device that produces a physical copy or hard copy of the computer’s output. Two basic types:  Impact printer  Non-impact printer

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 10 Impact printer Dot-matrix Impact Printer An impact printer is a printer that has a print head that contacts the paper to produce a character. It uses ink ribbon. It is noisy, produces Near-letter quality printouts, and is not commonly used today. Dot-matrix– Pins are used to make characters.

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 11 Inkjet Laser Nonimpact Printer The non-impact printer is the most commonly used printer today. It works quietly compared to an impact printer. Two types of nonimpact printers: Inkjet printer– Also called bubble-jet; makes characters by inserting dots of ink onto paper; letter-quality printouts; cost of printer is inexpensive but ink is costly. Laser printer works like a copier; quality determined by dots per inch (dpi) produced; color printers available; expensive initial costs but cheaper to operate per page.

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 12 Inkjet Laser Types of Printers Inkjet printer, also called a bubble-jet, makes characters by inserting dots of ink onto paper Letter-quality printouts Cost of printer is inexpensive but ink is costly Laser printer works like a copier Quality determined by dots per inch (dpi) produced Color printers available Expensive initial costs but cheaper to operate per page

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 13 Multifunction Printer A multifunction printer combines the functions of a non-impact printer, scanner, fax machine, and copier in one unit.

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 14 Plotter A plotter is a printer that uses a pen that moves over a large revolving sheet of paper. It is used in engineering, drafting, map making, and seismology.

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 15 WMAMIDIMP3WAV Beethoven 1:15 min Rocky 2:56 min Hornsby 48 sec Cheers 15 sec Click an icon to play music. Click the icon again to stop playing. Try clicking on Cheers while playing music. Audio Output: Sound Cards and Speakers Audio output is the ability of the computer to output sound. Two components are needed:  Sound card – Plays contents of digitized recordings  Speakers – Attach to sound card

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 16 Summary – Output Devices Monitors enable the user to view the computer’s processed data. The output is known as soft copy. The two types of monitors are the CRT and the LCD. Two basic types of printers are the impact and non-impact printer. A monitor’s quality is measured by screen size, resolution, and refresh rate. Printers produce permanent versions (hard copies) of the computer’s output. The two basic types of printers are the inkjet and laser.

Computers Are Your Future Chapter 5 © 200 Prentice-Hall, IncSlide 17 THE END