Ricoh Aficio Color 3006 Service Manual page 6

Signal Processing (in the Analog ASIC)............................................. 2-34
A/D Conversion .................................................................................. 2-34
Shading Circuit................................................................................... 2-35
D/A Conversion .................................................................................. 2-37
Scan Line Correction.......................................................................... 2-37
2.5.4 IPU SECTION BLOCK DIAGRAM ................................................. 2-38
2.5.5 IPU SECTION ................................................................................ 2-39
Picture Element Correction and Scanner Gamma Correction ............ 2-39
ACS (Auto Color Selection)................................................................ 2-41
Auto Letter/Photo Separation ............................................................. 2-42
Filtering and Color Conversion........................................................... 2-44
Changes in UCR Ratio with Image Density and Copy Mode ............. 2-50
UCA (Under Color Addition)............................................................... 2-50
Main Scan Magnification .................................................................... 2-51
Mirror Image....................................................................................... 2-51
Gamma (γ) Correction (Printer Gamma) ............................................ 2-52
Area Editing........................................................................................ 2-55
CPU ................................................................................................... 2-55
IPU Board Test................................................................................... 2-55
2.6 LASER EXPOSURE ............................................................................... 2-56
2.6.1 OVERVIEW ................................................................................... 2-56
2.6.2 OPTICAL PATH ............................................................................. 2-57
Overview ............................................................................................ 2-57
F-theta Lenses and the BTL............................................................... 2-59
Laser Synchronizing Detector Boards................................................ 2-60
Gradation Control (Laser Pulse Width and Laser Power Modulation) 2-61
600 DPI Writing .................................................................................. 2-62
Auto Power Control (APC) ................................................................. 2-63
LD Safety Switches ............................................................................ 2-64
2.6 DEVELOPMENT UNIT ........................................................................... 2-65
2.6.1 OVERVIEW ................................................................................... 2-65
2.6.2 REVOLVER MECHANISM............................................................. 2-66
Overview ............................................................................................ 2-66
Revolver Drive.................................................................................... 2-67
Revolver Home Position Detection..................................................... 2-68
2.6.3 DEVELOPMENT MECHANISMS................................................... 2-69
Overview ............................................................................................ 2-69
Development Drive............................................................................. 2-70
Developer Agitation............................................................................ 2-70
Toner Agitation................................................................................... 2-71
Development Bias .............................................................................. 2-72
Toner Supply Mechanism .................................................................. 2-73
Toner Cartridge Detection.................................................................. 2-74
Incorrect Toner Installation Prevention............................................... 2-74
Toner End Detection .......................................................................... 2-75
2.7 TRANSFER BELT UNIT ......................................................................... 2-76
2.7.1 OVERVIEW ................................................................................... 2-76
2.7.2 BELT TRANSFER MECHANISMS ................................................ 2-77
Transfer Belt Drive ............................................................................. 2-77
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