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Chapter 03 io csc&tts


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Chapter 03 io csc&tts

  1. 1. CHAPTERTHREE Discovering Computers Fundamentals, 2011 Edition Living in a Digital World
  2. 2. Objectives Overview Identify the keys and buttons commonly found on desktop computer keyboards, and describe how keyboards for mobile computers and devices differ from desktop computer keyboards Describe different mouse types Describe various types of touch screens and explain how a touch-sensitive pad works Describe various types of pen input 2
  3. 3. Objectives Overview Explain other types of input Explain the characteristics of LCD monitors, LCD screens, and CRT monitors Identify the purpose and features of speakers, headphones, and ear-buds; data projectors; and interactive whiteboards Summarize the various types of printers Identify input and output options for physically challenged users 3
  4. 4. What Is Input? • Input is any data and instructions entered into the memory of a computer 4
  5. 5. What Is Input? An input device is any hardware component that allows users to enter data and instructions into a computer 5
  6. 6. Keyboard • A keyboard is an input device that contains keys users press to enter data and instructions into a computer 6
  7. 7. Keyboard • Most desktop computer keyboards have… 7
  8. 8. Keyboard • An ergonomic keyboard has a design that reduces the chance of wrist and hand injuries • Ergonomics incorporates comfort, efficiency, and safety into the design of the workplace 8
  9. 9. Keyboard • Keyboards on mobile devices typically are smaller and/or have fewer keys • Some phones have predictive text input, which saves time when entering text using the phone’s keypad Page 191 Figure 5-3 9
  10. 10. Pointing Devices Page 189 10
  11. 11. Types of Pointing Devices: • Mouse • Devices used for games - joystick • Devices used in laptops – track ball, touch pad, pointing stick 11
  12. 12. Pointing Devices • A mouse is a pointing device that fits under the palm of your hand comfortably – Most widely used pointing device on desktop computers • A mouse can be wired (mechanical/ optical) or wireless (cordless) 12
  13. 13. Types: • Mechanical – small ball on underside rolls as mouse is moved • Optical – uses a light beam to monitor mouse movement • Cordless – uses either infrared or radio waves 13
  14. 14. • A touchpad is a small, flat, rectangular pointing device that is sensitive to pressure and motion • Sliding finger across pad moves pointer • Tapping with finger recognized as click Pointing Stick • A trackball is a stationary pointing device with a ball on its top or side • Usually has one or more buttons that work just like mouse buttons Touchpad Trackball Pointing Devices • A pointing stick is a small pressuresensitive pointing device shaped like a pencil eraser that is positioned between keys on a keyboard • Pushing post in any direction moves pointer 14
  15. 15. Pointing Devices • A handheld vertical lever with handgrip mounted on a base • User moves the lever in different directions to control the actions of the simulated vehicle or player • Distance and speed of movement control pointer position • Pressing trigger causes actions to take place. 15
  16. 16. Touch Screens and Touch-Sensitive Pads • A touch screen is a touch-sensitive display device • Position of finger on screen determines item to be input into system • Used at kiosks in public place such as malls 16
  17. 17. Touch Screens and Touch-Sensitive Pads Microsoft Surface Touch-sensitive pads 17
  18. 18. Graphic tablet • A flat, rectangular, electronic, p lastic board • Architects, mapmakers, desig ners, artists and home user create drawings by using a pressure sensitive pen (stylus) on a graphic tablet • Used to create or trace precise drawings. 18
  19. 19. Pen Input • With pen input, you touch a stylus or digital pen on a flat surface to write, draw, or make selections • A stylus -A small metal or plastic device that looks like a tiny ink pen. Often used in PDAs or pocket PCs • A pen digital- provide more functionality than a stylus, featuring electronic erasers and programmable buttons 19
  20. 20. Other Types of Input 20
  21. 21. Other Types of Input • Video games and computer games use a game controller as the input device that directs movements and actions of on-screen objects Gamepads Joysticks and Wheels Light guns Motionsensing controllers Wii Remote Dance pads 21
  22. 22. Other Types of Input 22
  23. 23. Other Types of Input • A digital camera is a mobile device that allows users to take pictures and store them digitally Studio cameras Field cameras Point-and-shoot camera 23
  24. 24. Other Types of Input 24
  25. 25. Other Types of Input • Two factors affect the quality of digital camera photos: Resolution • Resolution is the number of horizontal and vertical pictures in a display device • A pixel is the smallest element in an electronic display 25
  26. 26. Other Types of Input • Voice input is the process of entering input by speaking into a microphone • Voice recognition is the computer’s capability of distinguishing spoken words • Audio input is the process of entering any sound into the computer. **used – microphone - CD/DVD/Blu-ray Disk Players, - MIDI (musical instrument digital interface)external music devices such as electronic keyboard, guitars, drums, harmonica. 26
  27. 27. Other Types of Input • Music production software allows users to record, compose, mix, and edit music and sounds 27
  28. 28. Other Types of Input • Video input is the process of capturing full-motion images and storing them on a computer’s storage medium Record video on a digital video (DV) camera or use a video capture card to convert analog signals to digital Connect the camera to a port on the system unit Transfer video and images 28
  29. 29. Other Types of Input • A Web cam is a type of digital video camera that enables a user to: Capture video and still images Send e-mail messages with video attachments Broadcast live images over the Internet Add live images to instant messages Make video telephone calls 29
  30. 30. Other Types of Input • A video conference is a meeting between two or more geographically separated people 30
  31. 31. Other Types of Input • A flatbed scanner creates a file of the document in memory – Works in a manner similar to a copy machine 31
  32. 32. Other Types of Input • Optical character recognition (OCR) involves reading characters from ordinary documents • A turnaround document is a document you return to the company that creates and sends it 32
  33. 33. Other Types of Input • Optical mark recognition (OMR) reads hand-drawn marks such as small circles or rectangles 33
  34. 34. Other Types of Input • A bar code reader, also called a bar code scanner uses laser beams to read bar codes 34
  35. 35. Other Types of Input • RFID (radio frequency identification) uses radio signals to communicate with a tag placed in or attached to an object • An RFID reader reads information on the tag via radio waves • RFID can track: Tracking times of runners in a marathon Tracking location of soldiers Managing inventory Employee wardrobes Gauging pressure and temperature of tires Airline baggage Checking out library books Checking lift tickets of skiers Tracking toll payments 35
  36. 36. Other Types of Input • Magnetic stripe card readers read the magnetic stripe on the back of cards such as: Credit cards Entertainment cards Bank cards Other similar cards 36
  37. 37. Other Types of Input • MICR (magnetic ink character recognition) devices read text printed with magnetized ink • An MICR reader converts MICR characters into a form the computer can process • Banking industry uses MICR for check processing 37
  38. 38. Other Types of Input • Biometrics authenticates a person’s identity by verifying a personal characteristic Fingerprint reader Face recognition system Signature verification system Hand geometry system Iris recognition system Voice verification system Retinal scanners 38
  39. 39. Other Types of Input iris recognition system fingerprint reader 39
  40. 40. Other Types of Input • A terminal is a computer that allows users to send data to and/or receive information from a host computer A POS terminal records purchases, processes payment, and updates inventory An automated teller machine (ATM) allows users to access their bank accounts A DVD kiosk is a self-service DVD rental machine 40
  41. 41. What Is Output? • Output is data that has been processed into a useful form 41
  42. 42. Categories of output: • Text : memos, letters, press releases, report, classified advertisements, envelops, mailing labels, text messages. • Graphics : logos, charts, drawings, clip arts, photos. • Audio : songs, narrations, speeches • Video : video blogs, vodcast. 42
  43. 43. What Is Output? • An output device is any type of hardware component that conveys information to one or more people Display devices Speakers, headphones, and earbuds Printers Data projectors Interactive whiteboards 43
  44. 44. Display Devices: • A display device visually conveys text, graphics, and video information • Information on display device sometimes called softcopy • A monitor is packaged as a separate peripheral • 2 types of display devices: – Flat -panel display ( LCD, plasma, digital television /DTV) – CRT monitors 44
  45. 45. Display Devices :Flat-panel display • Liquid crystal display (LCD) uses a liquid compound to present information on a display device • Produce sharp, flicker free images • Mobile devices that contain LCD display : Notebook, Tablet PC, ultra personal computer, portable media player, smart phone and PDA Page 209 45
  46. 46. Resolution Response time Dot pitch Brightness Contrast ratio 46
  47. 47. Resolution: • Number of a horizontal and vertical pixel in a display device. • Sharpness and clarity of images • Higher resolution makes image sharper, display more text on the screen, makes some elements smaller. 47
  48. 48. Dot pitch: • Distance in millimeters between pixel on a display device. • Text created with a smaller dot pitch is easier to read. • Average dot pitch on LCD monitors and screen should be 0.30mm or lower. The lower the number, the sharper the image. 48
  49. 49. Response time: • The time in milliseconds (ms) that it takes to turn a pixel on or off. • LCD monitor’ and screens’ response time today range from 3 to 16 ms. The lower the number, the faster the response time. 49
  50. 50. Brightness: • Measured in nits. A nit is a unit of visible light intensity equal to one candela per square. • Candela is the standard unit of luminous intensity. • LCD monitor and screen range from 250 to 550 nits. The higher the nits, the brighter the images. 50
  51. 51. Contras ratio: • Describe the difference in light intensity between the brightness white and darkest black that can be displayed on an LCD monitor. • Contrast ratios today range from 500:1 to 2000:1. higher contrast ratios represent colours better. 51
  52. 52. Display Devices:Flat-panel display • Plasma monitors are display devices that use gas plasma technology and offer screen sizes up to 150 inches 52
  53. 53. Display Devices:Flat-panel display • Digital Television (DTV) -Uses digital signals to produce crisper, higher-quality output on LCD and plasma televisions • HDTV (high-definition television) is the most advanced form of digital television. • Great for game playing, watching movies, and browsing the Internet 53
  54. 54. Display Devices: CRT monitor • A CRT monitor is a desktop monitor that contains a cathode-ray tube Page 210 Figure 5-33 54
  55. 55. • Screen coated with tiny dots of phosphor material. Each dot consist of a red, blue and green phosphor. • What determines the quality of a CRT monitor? – Screen resolution – Text created with a smaller dot pitch is easier to read. – Refresh rate is speed at which monitor redraws images on screen. 55
  56. 56. Printers • A printer produces text and graphics on a physical medium • Before purchasing a printer, ask yourself a series of questions 56
  57. 57. Printers 57
  58. 58. Categories of printer: • Non impact printer (Int-jet, Photo,Laser, Thermal,Mobile, Label, Postage, Plotter and multifunction peripheral (MFP) • Impact printer. (Dot matrix and line) 58
  59. 59. Printers : Non impact printer • A nonimpact printer forms characters and graphics on a piece of paper without actually striking the paper Ink-jet printers Photo printers Mobile printers Laser printers Plotters Thermal printers Largeformat printers 59
  60. 60. Printers : Non impact printer • An ink-jet printer forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper – Print in Color or black-and-white – Printers with a higher dpi (dots per inch) produce a higher quality output – Less expensive than laser printer 60
  61. 61. Printers: Non impact printer A photo printer produces color photo-lab-quality pictures • Most use ink-jet technology • PictBridge allows you to print photos directly from a digital camera • Print from a memory card and preview photos on a built-in LCD screen 61
  62. 62. Printers: Non impact printer 62
  63. 63. Printers : Non impact printer • print text and graphics in high quality resolution, ranging from 1200 to 2400 dpi. •Typically cost more than ink jet printer, but is much faster Highspeed Blackandwhite Laser printer Highquality Color 63
  64. 64. Printers: Non impact printer • A multifunction peripheral (MFP) is a single device that prints, scans, copies, and in some cases, faxes – Sometimes called an all-in-one device 64
  65. 65. Printers : Non impact printer • A thermal printer generates images by pushing electrically heated pins against the heat-sensitive paper 2 types: 1. Dye-sublimation printer 2. Thermal wax printer Pages 215 – 216 Figure 5-40 65
  66. 66. Printers: Non impact printer • A mobile printer is a small, lightweight, batte ry-powered printer that allows a mobile user to print from a mobile device Page 216 Figure 5-41 66
  67. 67. Printers: Non impact printer • Plotters are used to produce high-quality drawings • Large-format printers create photo-realistic quality color prints on a larger scale Page 216 Figure 5-42 67
  68. 68. Printers: Non impact printer • Label printer : Small printer that print on adhesive –type material. • Most also print bar codes • Postage printer has built-in digital scale and print postage stamps. 68
  69. 69. Printers: Impact printers • 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 Page 217 Line printer 69
  70. 70. Printers: Impact printers • A dot-matrix printer produces printed images when tiny wire pins on a print head mechanism strike an inked ribbon • Speed measured by the number of character per second (cps) Page 217 Figure 5-43 70
  71. 71. Printers: Impact printers • A line printer prints an entire line at a time • High speed impact printer • Speed measured in lines per minute (lpm) Page 217 Figure 5-43 71
  72. 72. Other Output Devices • 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 Page 217 Figure 5-44 72
  73. 73. Other Output Devices • Headphones are speakers that cover or are placed outside of the ear • Earbuds (also called earphones) rest inside the ear canal 73
  74. 74. Other Output Devices 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 Page 218 74
  75. 75. Other Output Devices • A data projector is a device that takes the text and images displaying on a computer screen and projects them on a larger screen Page 218 Figure 5-45 75
  76. 76. Other Output Devices • An Interactive Whiteboards is a touch-sensitive device, resembling a dry-case board, that display the image on a connected computer screen. • A presenter control the computer by clicking a remote control, touching the whiteboard, drawing on or erasing the whiteboard with a special digital pen and eraser, or writing on a special tablet. • Notes written can be directly on the computer. 76
  77. 77. Putting It All Together 77
  78. 78. Putting It All Together 78
  79. 79. Putting It All Together 79
  80. 80. Input and Output Devices for Physically Challenged Users Head-mounted pointer Braille printer 80
  81. 81. Summary Various techniques for entering input and several commonly used input device Various methods of output and several commonly used output devices 81
  82. 82. CHAPTER 3 Discovering Computers Fundamentals, 2011 Edition Living in a Digital World