Ricoh U-C1 B051 Service Manual page 10

6. DETAILED SECTION DESCRIPTIONS....................................... 6-1
6.1 OVERVIEW .............................................................................................. 6-1
6.1.1 MECHANICAL COMPONENTS....................................................... 6-1
6.1.2 PAPER PATH .................................................................................. 6-2
6.1.3 DRIVE COMPONENTS ................................................................... 6-3
Layout .................................................................................................. 6-3
Drive Power Path ................................................................................. 6-4
6.1.4 ELECTRICAL COMPONENTS ........................................................ 6-5
Scanner Unit ........................................................................................ 6-5
Image Transfer..................................................................................... 6-6
Paper Path ........................................................................................... 6-7
Development Units............................................................................... 6-8
Boards.................................................................................................. 6-9
6.2 BOARD STRUCTURE ............................................................................ 6-10
6.2.1 BLOCK DIAGRAM ......................................................................... 6-10
6.2.2 CONTROLLER .............................................................................. 6-12
6.3 COPY PROCESS ................................................................................... 6-14
6.4 PROCESS CONTROL............................................................................ 6-16
6.4.1 OVERVIEW.................................................................................... 6-16
6.4.2 PROCESS CONTROL STEPS ...................................................... 6-16
Six Steps ............................................................................................ 6-16
When is Process Control Done? ........................................................ 6-16
Supplementary Information on Process Control................................. 6-17
6.5 SCANNING............................................................................................. 6-19
6.5.1 OVERVIEW.................................................................................... 6-19
6.5.2 SCANNER DRIVE ......................................................................... 6-20
Book Mode ......................................................................................... 6-20
ARDF Mode ....................................................................................... 6-20
6.5.3 ORIGINAL SIZE DETECTION ....................................................... 6-21
6.6 IMAGE PROCESSING ........................................................................... 6-23
6.6.1 OVERVIEW.................................................................................... 6-23
6.6.2 SBU BLOCK DIAGRAM................................................................. 6-24
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
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