1. Output

2. Objectives Describe the four categories of output Describe characteristics of a CRT monitor and factors that affect its quality Explain the relationship between a video card and CRT monitor Summarize the characteristics of LCD monitors, LCD screens, gas plasma displays,and HDTVs Differentiate between an impact printer and a non-impact printer

3. Objectives Summarize the characteristics of ink-jet printers, photo printers, laser printers, thermal printers, mobile printers, label and postage printers, and plotter and large-format printers Describe the methods used for wireless printing Identify the output characteristics of fax machines and fax modems, multifunction peripherals, data projectors, joysticks, and wheels Identify output options for physically challenged users

4. Output Output is data that has been processed into a useful form, called information video audio text graphics

5. Output An output device is any component that can convey information to the user. printer monitor speakers

6. Display Devices Output device that visually conveys information Information on display device sometimes called soft copy

7. Display Devices The CRT monitor CRT monitor screen cathode ray tube The major component is a CRT (Cathode Ray Tube) The front of the tubs is coated with phosphors, arranged in triangles of red, green and blue dots. This group of three colors is called a triad. Each triad on the CRT is called a pixel or picture element.

8. Display Devices The CRT monitor CRT monitors come in specific sizes 15, 17, 19, 21, and 22 inch screen size Viewable size is diagonal measurement of actual viewing area provided by the monitor screen size viewable size

9. Display Devices How video is sent to the display device Step 1. The CPU sends rudimentary digital video data to the video card.

10. Display Devices How video is sent to the display device Step 2. The video card’s digital-to-analog converter (DAC) converts the digital video data to an analog signal.

11. Display Devices How video is sent to the display device Step 3. The analog signal is sent as a red, green and blue signal through a cable to the CRT monitor.

12. Display Devices How video is sent to the display device Step 4. Electron guns fire the three color signals to the front of the CRT.

13. Display Devices How video is sent to the display device Step 5. An image is displayed on the screen when the electrons hit phosphor dots on the front of the screen

14. Display Devices Resolution There are two factors that effect display clarity, resolution and dot pitch. Resolution The number of horizontal and vertical lines used to create the images. 800 horizontal lines 600 vertical lines

15. Display Devices Bit Depth Bit depth is the number of bits a video card uses to store information sent to each pixel Bit depth determines the maximum number of colors a video card can display 8 bit output Uses 8 bits to store information about each pixel Can display 256 different colors 2 8 = 256 colors 24 bit output Uses 24 bits to store information about each pixel Can display 16.7 million different colors 2 24 = 16.7 million colors

16. Display Devices Flat-Panel Displays They use liquid crystals arranged in color triads.

17. Display Devices Flat-Panel Displays A liquid crystal are actually a sandwich of a number of materials.

18. Display Devices Flat-Panel Displays A light source is located at the back of the display, usually a bank of fluorescent tubes.

19. Display Devices Flat-Panel Displays There are two polarizing filters, one located next to the light source.

20. Display Devices Flat-Panel Displays Next is an alignment layer that controls the alignment of the liquid crystals.

21. Display Devices Flat-Panel Displays There is a color filter which will be either red, green or blue.

22. Display Devices Flat-Panel Displays The liquid crystals are located in the center of the sandwich.

23. Display Devices Flat-Panel Displays There are set of wires attached to the alignment layer that can apply a DC voltage to the liquid crystals

24. Display Devices Flat-Panel Displays When the light source is turned on it starts out as un- polarized light.

25. Display Devices Flat-Panel Displays When it passes through the first polarizing filter the light is polarized in one direction

26. Display Devices Flat-Panel Displays With a positive DC current is applied to the liquid crystals they align in the same direction as the polarizer and the light passes through unaffected.

27. Display Devices Flat-Panel Displays The light passes through the color filter.

28. Display Devices Flat-Panel Displays The light then passes through the second polarizing filter and is seen.

29. Display Devices Flat-Panel Displays However when the DC voltage is negative the crystal cause the light to twist 90 0.

30. Display Devices Flat-Panel Displays The light again passes through the filter making it green in color.

31. Display Devices Flat-Panel Displays However now the light is 90 0 out of alignment with the second polarizing filter and no light appears.

32. Display Devices Flat-Panel Displays Mobile devices that have LCD screens Notebooks Tablet PC’s PDA’s Smart Phones

33. Display Devices Using an LCD monitor with a video card There are three ports on the back of most video cards 15 pin monitor port S-video port DVI port Because most LDC monitors are digital you use the DVI port to attach them to the PC.

34. Display Devices Gas plasma monitor Displays image by applying voltage to layer of gas Larger screen size and higher display quality than LCD, but much more expensive

35. Display Devices HDTV There are three digital TV formats 480 p The picture created is 704 X 480 lines equivalent to a standard TV resolution. 720 p The picture created is 1280 X 720 lines equivalent to standard TV format for a HDTV set 1080 i The picture created has a resolution of 1920 X 1080 lines true HDTV format.

36. Display Devices HDTV Aspect Ratio Aspect ration refers to the width and height of the picture created. Standard TV has an aspect ration of 4:3 HDTV has an aspect ration of 16:9

37. Printers Printers are device that produces text and graphics on printer media. Result is hard copy, or printout Two orientations: portrait and landscape portrait landscape

38. Printer - Types Impact printers Dot-matrix printer Impact printer that produces printed images when tiny wire pins strike ribbon Forms characters by striking mechanism against inked ribbon that contacts paper

39. Printer - Types Impact printers Line Printer High-speed impact printer that prints entire line at a time Speed measured in lines per minute (lpm)

40. Printer - Types Inkjet printers A type of nonimpact printer that sprays tiny drops of liquid ink onto paper Nonimpact printer forms characters and graphics without striking paper Prints in black-and-white or color on a variety of media types

41. Printer - Types Inkjet printers The resolution of a printer Sharpness and clarity of the image produces. Measured by number of dots per inch (dpi) printer can output

42. Printer - Types Laser printers High-speed, high-quality nonimpact printer Prints text and graphics in very high-quality resolution, ranging from 600 to 2,400 dpi Typically costs more than ink-jet printer, but is much faster Can print in both black and white and color.

43. Printer - Types Laser printers drum rotating mirror drum rotating mirror drum rotating mirror drum rollers rotating mirror drum 1: Drum rotates as paper is fed through 2: Mirror deflects laser beam across surface of drum 3: Laser beam creates charge that causes toner to stick to drum 4: As drum rotates, toner transfers from drum to paper 5: Rollers use heat and pressure to fuse toner to paper How a laser printer work

44. Printer - Types Types of printing media Plane paper Coated paper Photographic paper Transparencies Misc Specific types of media for specific types of printers.

45. Printer - Types Thermal printer Generates images by pushing electrically heated pins against heat-sensitive paper professional One specific type of thermal printer is the label printer Can print labels and barcodes.

46. Printer - Types Dye-sublimation printer Uses heat to transfer dye to specially coated paper Used to create high quality photographs.

47. Printer - Types Mobile printer Small, lightweight, battery-powered printer that allows mobile user to print from notebook computer, Tablet PC, or PDA while traveling

48. Printer - Types Plotter Sophisticated printer used to produce high-quality drawings Uses pens to create the images. Large-format printer creates photo-realistic-quality color prints

49. Other types of Output Devices Facsimile (fax) machine Device that transmits and receives documents over telephone lines

50. Other types of Output Devices Multifunction peripheral Provides functionality of printer, scanner, copy machine, and fax machine

51. Other types of Output Devices Data projector Device that takes image from computer screen and projects it onto larger screen

52. Output Devices for Physically Challenged Users Windows Magnifier command enlarges text and other items on screen Change Window settings, such as increasing size or changing color of text to make words easier to read Blind users can work with voice output Braille printer outputs information in Braille onto paper