Ricoh A-C2 - Page 9

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6.4.1 OVERVIEW ....................................................................................6-11
SCANNER DRIVE ..............................................................................6-12
Book Mode..........................................................................................6-12
ADF mode...........................................................................................6-12
6.4.3 ORIGINAL SIZE DETECTION IN PLATEN MODE.........................6-13
6.5 IMAGE PROCESSING............................................................................6-15
6.5.1 OVERVIEW ....................................................................................6-15
6.5.2 SBU (SENSOR BOARD UNIT).......................................................6-16
6.5.3 AUTO IMAGE DENSITY (ADS)......................................................6-17
6.5.4 IPU (IMAGE PROCESSING UNIT).................................................6-18
Overview.............................................................................................6-18
6.5.5 IMAGE PROCESSING MODES.....................................................6-19
6.5.6 SUMMARY OF IMAGE PROCESSING FUNCTIONS....................6-21
6.5.7 IMAGE PROCESSING STEPS AND RELATED SP MODES.........6-22
Text Mode...........................................................................................6-22
Text/Photo Mode ................................................................................6-23
Photo Mode ........................................................................................6-24
Pale (Low-Density Mode)....................................................................6-25
Generation Copy Mode.......................................................................6-26
Auto shading (shading correction) ......................................................6-27
Background erase...............................................................................6-27
Independent dot erase........................................................................6-28
Filtering...............................................................................................6-29
Pre-Filter.............................................................................................6-29
Text Mode...........................................................................................6-30
Photo Mode ........................................................................................6-31
Text/Photo Mode ................................................................................6-32
Low Density Mode ..............................................................................6-33
Generation Mode................................................................................6-33
Main scan magnification and reduction...............................................6-34
γ correction..........................................................................................6-34
Gradation processing..........................................................................6-34
Line width correction...........................................................................6-35
6.6 LASER EXPOSURE................................................................................6-36
6.6.1 OVERVIEW ....................................................................................6-36
6.6.2 AUTO POWER CONTROL (APC)..................................................6-37
6.6.3 DUAL BEAM WRITING ..................................................................6-38
6.6.4 LASER BEAM PITCH CHANGE MECHANISM..............................6-39
6.6.5 LD SAFETY SWITCHES ................................................................6-40
6.7 PHOTOCONDUCTOR UNIT (PCU) ........................................................6-41
6.7.1 OVERVIEW ....................................................................................6-41
6.7.2 DRIVE MECHANISM......................................................................6-42
6.7.3 DRUM PAWLS ...............................................................................6-42
6.7.4 DRUM TONER SEALS...................................................................6-42
6.8 DRUM CHARGE .....................................................................................6-43
6.8.1 OVERVIEW ....................................................................................6-43
6.8.2 CHARGE ROLLER VOLTAGE CORRECTION..............................6-44
Correction for Environmental Conditions ............................................6-44
Correction for paper width and thickness (by-pass tray only) .............6-45