vi
By Original Type .................................................................................6-15
6.5.4 IPU (IMAGE PROCESSING UNIT).................................................6-16
Overview.............................................................................................6-16
Image Processing Modes ...................................................................6-17
Image Processing Path.......................................................................6-18
Original Modes....................................................................................6-19
SP Modes for Each Image Processing Step .......................................6-19
Auto Shading ......................................................................................6-21
White Line Erase ................................................................................6-22
Black Line Erase .................................................................................6-22
Scanner Gamma (
γ
) Correction ..........................................................6-23
Main Scan Magnification.....................................................................6-24
Mirroring for ADF Mode ......................................................................6-24
Filtering ...............................................................................................6-25
ID Gamma (
γ
) Correction ....................................................................6-26
Gradation Processing .........................................................................6-27
6.5.5 IMB (MEMORY CONTROLLER AND DRAM) ................................6-28
6.5.6 VIDEO CONTROL UNIT (VCU)......................................................6-29
Fine Character and Image (FCI) .........................................................6-29
Printer Gamma Correction ..................................................................6-29
6.6 LASER EXPOSURE................................................................................6-30
6.6.1 OVERVIEW ....................................................................................6-30
6.6.2 AUTO POWER CONTROL (APC) ..................................................6-31
6.6.3 LD SAFETY SWITCH .....................................................................6-32
6.7 PHOTOCONDUCTOR UNIT (PCU) ........................................................6-33
6.7.1 OVERVIEW ....................................................................................6-33
6.7.2 DRIVE.............................................................................................6-34
6.8 DRUM CHARGE .....................................................................................6-35
6.8.1 OVERVIEW ....................................................................................6-35
6.8.2 CHARGE ROLLER VOLTAGE CORRECTION ..............................6-36
Correction for Environmental Conditions ............................................6-36
6.8.3 ID SENSOR PATTERN PRODUCTION TIMING............................6-37
6.8.4 DRUM CHARGE ROLLER CLEANING ..........................................6-38
6.9 DEVELOPMENT .....................................................................................6-39
6.9.1 OVERVIEW ....................................................................................6-39
6.9.2 DRIVE.............................................................................................6-40
6.9.3 DEVELOPER MIXING ....................................................................6-40
6.9.4 DEVELOPMENT BIAS ...................................................................6-41
6.9.5 TONER SUPPLY ............................................................................6-42
Toner Bottle Replenishment Mechanism ............................................6-42
Toner Supply Mechanism ...................................................................6-43
6.9.6 TONER DENSITY CONTROL ........................................................6-44
Overview.............................................................................................6-44
Toner Density Sensor Initial Setting....................................................6-46
Toner Concentration Measurement ....................................................6-46
Vsp/Vsg Detection ..............................................................................6-46
Toner Supply Reference Voltage (Vref) Determination.......................6-46
Toner Supply Determination ...............................................................6-46
Toner Supply Motor On Time Determinations.....................................6-47
