Ricoh B051 Service Manual page 19

Signal Processing ...............................................................................6-24
A/D Conversion...................................................................................6-24
White Level Correction........................................................................6-24
Others .................................................................................................6-24
Black Level Correction ........................................................................6-25
VPU Test Mode ..................................................................................6-25
6.6.3 IMAGE PROCESSING ...................................................................6-26
Shading Correction .............................................................................6-26
Picture Element (Dot Position) Correction ..........................................6-26
Scan Line Correction ..........................................................................6-26
Scanner Gamma Correction (RGB Gamma Correction) .....................6-27
Filtering ...............................................................................................6-27
ADS (Auto Image Density Selection) ..................................................6-27
Image Separation................................................................................6-28
ACS (Auto Color Selection) ................................................................6-28
Color Conversion ................................................................................6-29
Main Scan Magnification.....................................................................6-29
Printer Gamma Correction ..................................................................6-30
Error Diffusion .....................................................................................6-32
ASICs on the BICU Board Test...........................................................6-32
6.7 PHOTOCONDUCTOR UNIT (PCU) ........................................................6-33
6.7.1 OVERVIEW ....................................................................................6-33
6.7.2 CHARGE CORONA UNIT ..............................................................6-34
Power Supply......................................................................................6-34
Grid and Wire Cleaning.......................................................................6-34
Quenching ..........................................................................................6-35
6.7.3 OPC BELT DRIVE ..........................................................................6-35
6.7.4 OPC BELT CLEANING UNIT .........................................................6-36
Bottle Detection ..................................................................................6-36
Waste Toner Collection.......................................................................6-36
Drive ...................................................................................................6-37
6.7.5 IMAGE TRANSFER BELT UNIT ....................................................6-37
Drive ...................................................................................................6-37
Belt Mark Detection.............................................................................6-38
Transfer Roller ....................................................................................6-38
6.7.6 IMAGE TRANSFER BELT CLEANING UNIT .................................6-39
Image Transfer Belt Cleaning .............................................................6-39
Waste Toner Collection.......................................................................6-39
Set Switch and Full Sensor.................................................................6-39
Contact Mechanism ............................................................................6-40
Power Supply......................................................................................6-41
Drive ...................................................................................................6-41
6.8 LASER EXPOSURE................................................................................6-42
6.8.1 OVERVIEW ....................................................................................6-42
6.8.2 POLYGON MIRROR MOTOR UNIT...............................................6-43
Speed .................................................................................................6-43
6.8.3 SYNCHRONIZATION DETECTOR ................................................6-43
6.8.4 LD UNIT..........................................................................................6-43
6.8.5 LD SAFETY SWITCH .....................................................................6-44
SM
CÓPIA NÃO CONTROLADA
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CÓPIA NÃO CONTROLADA
B051/B052