Output Device of Computer

•         What is output?

•          Data that has been processed into a useful form called information

•         What is is an output device ?

             •         Any hardware component that can convey information to use

•         What is a Display device?

•          Output device that visually conveys information.Information on display device sometimes called softcopy. mnitor houses display device as separate peripheral

   

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•          What is a CRT monitor ?

•          Contains Cathode-Ray Tube (CRT)

•          Large sealed, glass screen

•          Screen coated with tiny dots of phosphor material

•          Pixel or picture element is single point in electronic image

•          Three dots (red, blue and green) combine to make a pixel

•          Common sizes are 15, 17, 19, 21 and 22 inches

•          Viewable size is diagonal measurement of actual viewing area provided by the monitor

•          What is Resolution?

•          Describes the sharpness and clarity of image

•          Higher resolution makes image sharper, displays more text on screen, makes some elements smaller

•          Refresh rate is speed at which monitor redraws images on screen

•          What is Dot pitch?

•          Measure of the distance between pixels

•          Sometimes called pixel pitch

•          Smaller the distance between the pixels, the sharper the image

•          What is Refresh Rate ?

•          Speed at which monitor redraws images on the screen

•          What is a video card?

•          Converts digital output from computer into analogue video signal

•          Controls how display device produces picture

•          Also called graphics card or video adapter

•         What is Bit depth?

•          Number of bits a video card uses to store information about each pixel

•          Also called colour depth

•          Determines number of colours a video card can display Greater the number of
           bits, better the resulting image

                     

•               What are Video standards ?

•          Video Electronics Standards Association (VESA) develops video standards

•          What are various video card configurations ?

•          What is Electromagnetic radiation (EMR) ?

•          Magnetic field that travels at speed of light

•          Small amount produced by all CRT monitors

•          LCD monitors do not pose this risk

•          What is a Liquid crystal display (LCD) monitor?

•          Uses liquid crystals between two sheets of material to present information on 
           screen

•          Electric current passes through crystals, which creates images on the screen

•          Takes up less desk space than CRT monitor

•          Consumes less than one-third the power

•          Where are some features of LCD screens?

•          Lightweight and compact

•          Consumes less than one-third of the power than does a CRT monitor

•          Ideal for notebook and handheld computers

•          What is a Printer ?

•          Output device that produces text and graphics on paper

•          Result is hard copy or printout

•          Two orientations : Portrait and Landscape

•          Types of printers :-

•          Impact printers

•          Non-impact printers

•         What is an impact printer?

•          Forms characters by striking a mechanism against ink ribbon that physically 
           contacts paper

•          Ideal for printing multipart forms

•          Can withstand dusty environments, vibrations and extreme temperatures

•          Types of impact printers :

•          Dot-matrix printer

•          Line printer

•          What is a Dot-matrix printer?

•          Impact printer that produces printed images when tiny wire pins on print head 
           mechanism strike inked ribbon

•          Impact printer forms characters by striking mechanism against inked ribbon 
           that contacts paper

•          Most use continuous-form paper

  

•          How does a Dot-matrix printer work?

•          When ribbon presses against paper, it creates dots that form characters and
            graphics

•          A higher number of pins (9 to 24) means printer prints more dots per character,
           which results in high

•          What is a Line printer?

•          High-speed impact printer that prints entire line at a time

•          Speed measured in lines per minute (lpm) it can print

•          Band printer prints fully formed characters using a hammer mechanism

•          Shuttle-matrix printer is high-speed printer that works like dot-matrix printer

•         What is a Non-impact printer?

•          Forms characters and graphics on piece of paper without actually striking 
           paper.

•          Types of non-impact printers :

•          Ink-Jet printer

•          Laser printer

•          Thermal printer

•         What is an Ink-jet printer?

•          A type of non-impact printer that sprays tiny drops of liquid ink onto paper

•          Non-impact printer forms characters and graphics without striking paper

•          Prints in black-and-white or colour on a variety of paper types.

•          What is the Resolution of  printer?

•          Sharpness and clarity

•          Measured by number of dots per inch (dpi) printer can output

•         What is a Laser printer?

•          High-speed, high-quality non-impact printer

•          Prints text and graphics in very high-quality resolution, ranging from 600 to
           2,400 DPI (Dots Per Inch).

•          Typically costs more than ink-jet printer, but is much faster

•          What is a Thermal printer?

•          Generally images by pushing electrically heated pins against heat-sensitive paper

•          Dye-sublimation printer, also called a digital photo printer

•          Uses heat to transfer dye to specially coated paper

•          What is a Mobile printer?

•          Small, lightweight, battery-powered printer that allows mobile user to print from 
            notebook computer, Tablet PC or PDA while traveling

•          What is a Label printer?

o        Small printer that prints on adhesive-type material

o        Most also print bar codes

o        Postage printer has built-in digital scale and prints postage stamps

Ø      What is a Plotter?

o        Sophisticated printer used to produce high-quality drawings

o        Large-format printer creates photo-realistic-quality colour prints

•          What is wireless printing?

•          Output transmitted to printer wirelessly via infrared light waves or radio waves

•          Bluetooth printing uses radio waves

•          Devices need to be within 30-foot range

•          What is an Audio output device?

•          Computer component that produces music, speech or other sound

•          Speakers and headsets are common devices

•          What is voice output?

•          Computer talks to you through speakers on computer

•          What is Internet telephony?

•          Allows you to have conversation over Web, just as if you were talking on the 
           telephone

•          What is a facsimile (fax) machine?

•          Device that transmits and receives documents over telephone lines

•          What is a Multifunction peripheral?

•          Provides functionality of printer, scanner, copy machine and fax machine.

•          What is a Data projector?

•          Device that takes image from computer screen and projects it onto larger 
           screen.

•          What is a Point of Sale (POS) terminal?

•          Records purchases, processes credit or debit cards, and updates inventory

•          Swipe credit or debit card through card reader, which reads customer’s personal data
            from magnetic strip

•          Output from POS terminals serves as input to host computer

•          What is an Automatic Teller Machine (ATM)?

•          Self-service banking machine that connects to host computer through network