1. Chapter-2 Overview of Graphics Systems

4. electron gun phosphor coated screen heating filament cathode control grid focusing anode accelerating anode Horizontal deflection plates vertical deflection plates CRT

7. Red Orange Green Yellow Beam penetration method

9. COLOUR GUNS Screen Shadow mask Delta-Delta method Phosphor dot triangle

10. COLOUR GUNS Screen Shadow mask In-line method

13. Architecture of simple Raster graphics system CPU System Memory System Bus I/O devices Video controller Monitor Frame buffer A fixed area of system memory reserved for frame buffer

14. Raster Scan Memory Requirements  Interlacing * Even lines first * Odd lines next * 50 Hz to avoid flicker Memory Requirements depends on * resolution * colors, the system supports ex: For a resolution of 1024 * 768 Resolution with 8-bits per pixel( 256 colors ), it needs 768 Kb of memory.

15. Raster-Scan display processor CPU System Memory System Bus I/O devices Display processor memory Frame Buffer Video controller Display processor Monitor

17. Raster Scan Generator X Register Y Register Memory Address Frame Buffer Pixel Register Horizontal and vertical deflection voltages Intensity Video controller addr (x,y) = base address + (x max – x min )(y – y min ) + ( x – x min )

18. Video controller  Co- ordinate system  Frame buffer locations are referenced in Cartesian co-ordinates.  Co-ordinate origin * Lower left screen corner. * Upper left screen corner.  Refresh operations of video controller  Top-to-bottom , Left-to-Right  X register(initial value = 0).  Y register (initial value = y max )

19. scan line Horizontal retrace Vertical retrace RASTER SCAN

20. Frame Buffers Rotating Memory Shift Register Multiple Plane

21. 1 1-bit register black and white display 1 Digital-to-Analog converter Frame buffer screen

22. 2-bit register black , white - gray color display Digital-to-Analog converter Frame buffer screen 1 1 1 1

23. Frame buffer Digital to Analog converters 1-bit registers simple color graphics display COLOUR GUNS screen 1 0 1 1 1 0 RED GREEN BLUE

24. Frame buffer screen multi color grpahics display 3-bit registers COLOUR GUNS Digital to Analog converters RED GREEN BLUE 1 0 0 0 1 1 1 1 0

25. Frame buffer screen multi color grpahics display (Look-up tables) 3-bit registers COLOUR GUNS W-bit Digital to Analog converters W-bit Look-up table 2 n entries RED GREEN BLUE 1 0 1 0 1 1 0 1 0

28. Random scan system CPU System Memory System Bus I/O devices Display processor Monitor Graphics commands are translated into a display file stored in the system memory.

29. RANDOM SCAN

31. + very high resolution. + Easy animation. + Little memory requirements. - Can’t draw a complex image (flicker) . - Limited colour capability. - Very expensive.

32. flood gun writing gun writing beam electrons screen storage grid collector DVST

36. Neon gas plasma panel

37. polarizer polarizer Transparent conductor Transparent conductor On State Nematic Liquid Crystal Liquid Crystal Display

38. polarizer polarizer Transparent conductor Transparent conductor Off State Nematic Liquid Crystal Liquid Crystal Display

54. Output Devices Hard copy Printers Plotters Storage Refresh Raster Random Screen D.V.S.T Flat panel display Laser scan L.C.D Soft copy

55. Element Dot matrix Line Inkjet Printers impact non impact Laser printers

56. Flat bed Drum Plotters

58. Co-ordinate Representations 1 1 1 Modeling co-ordinates World co-ordinates Normalized co-ordinates

60. The End

61. laser modulator focusing lense x-y deflectors photochromic film light source screen stored picture beam refresh beam projection light LASER SCAN