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CHAPTER 7: UNDERSTANDING OUTPUT

• Output is data that has been processed into a useful form.
• An output device is any type of hardware component that conveys information to one or more people.

Display Devices

• A display devices visually conveys text, graphics, and video information.
• A monitor is packaged as a separated peripheral
• LCD monitor
• Widescreen
• Liquid crystal display (LCD) uses a liquid compound to present information on a display device.
• Active-matrix display
• Passive-matrix display
• The quality of an LCD monitor or LCD screen depends primarily on:
• Resolution
• is the number of horizontal and vertical pixels in a display device.
• A higher resolution uses a greater number of pixels.
• Response time
• Brightness
• Dot pitch
• Contrast ratio
• The graphics processing unit (GPU) controls the manipulation and display of graphics on a display device.
• LCD monitors use a digital signal and should plug into a DVI port, an HDMI port, or a Display port.
• Plasma monitors are display devices that use gas plasma technology and offer screen sizes up to 150 inches.
•  Televisions also are a good output device.
• Require a convert if you are connecting your computer  to an analog television.
• Digital television (DTV) offers a crisper, higher-quality output. 
• HDTV is the most advanced form of digital television.
• A CRT monitor is a desktop monitor that contains a cathode-ray tube.
• Have a much larger footprint than do LCD monitors.

Printers

• A printer produces text and graphics on a physical medium.
• Printed information is called a hard copy, or printout.
• Landscape or portrait orientation.
• Various ways users print documents and photos
• Notebook  computer wirelessly communicates with system unit, which is connected to the printer on the home network.
• Printer prints photos in camera when camera sits in docking station.
• Printer prints image on memory card removed from camera and inserted in printer.
• Smart phone communicates with printer wirelessly.
• Digital camera communicates with printer wirelessly.
• A nonimpact printer  forms characters and graphics on a piece of paper without actually striking the paper.
• Ink-jet printers
• forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper.
• Color or black and white
• Printers with a higher dpi (dots per inch) produce a higher quality output.
• Photo printers
• produces color photo-lab-quality pictures
• Most use ink -jet technology
• PictBridge allows you to prit photos directly from a digital camera.
• Print from a memory card and preview photos on a built-in LCD screen.
• Laser printers
• High speed
• Black and white
• High quality
• Color
• Thermal printers
• generates images by pushing electrically heated pins against the heat sensitive paper.
• Thermal wax-transfer printer
• Dye-sublimation printer
• Mobile printers
• is a small,lightweight, battery-powered printer that allows a mobile user to print form a notebook computer, smart phone, or other mobile device.
• Label and postage printers
• A label printer is a small printer that prints on adhensive-type material.
• A postage printer prints postage stamps
• Postage also can printed on other types of printers.
• Plotters
• are used to produce high quality drawings.
• Large format printers
• create photo-realistic quality color prints on a larger scale.
• How a Black and White Laser Printer Works
• Step 1: After the user sends an instruction to print a document, the drum rotates as gears and rollers feed a sheet of paper into the printer.
• Step 2: A rotating mirror deflects a low powered laser beam across the surface of a drum.
• Step 3: The laser beam creates a charge that causes toner to stick to the drum.
• Step 4: As the drum continues to rotate and press against the paper, the toner transfer from the drum to the paper.
• Step 5: A set rollers uses heat and pressure to fuse the toner permanently to the paper.
• A multifunction peripheral (MFP) is a single device that prints, scans, copies, and in some cases, faxes.
• Sometimes called an all in one device.
• Impact printers form characters and graphics on a piece of paper by striking a mechanism against an inked ribbon that physically contacts the paper.
• Dot-matrix printer
• produces printed images when tiny wire pins on a print head mechanism strike an inked ribbon.
• Line printer
• prints an entire line at a time.

Speakers, Headphones, and Earbuds

• An audio output device produces music, speech, or other sounds.
• Most computer users attach speakers to their computers to:
• Generate higher quality sounds for playing games.
• Interact with multimedia presentations.
• Listen to music
• View movies
• Headphones are speakers that cover or are placed outside of the ear.
• Earbuds (also called earphones) resit inside the ear canal.
• Some speakers are specifically designed to play audio from a portable media player.
• Wireless speakers
• Voice output occurs when you hear a person's voice or when the computer talks to you through the speakers.
• Some Web sites dedicate themselves to providing voice output.
• Often works with voice input.
• VoIP uses voice output and voice input.

Other Output Devices

• are available for specific uses and applications
• Data projectors
• is a device that takes the text and images displaying on a computer screen and projects them on a larger screen.
• LCD projector
• Digital light processing (DLP) projector
• Interactive whiteboards
• is a touch sensitive device, resembling a dry-erase board, that displays the image on a connected computer screen.
• Force-feedback game controllers
• sends resistance to the device in a response to actions of the user.
• Tactile output
• provides the user with a physical response from the device