Canon iR8500 Service Manual page 30

3.4 Sequence of Operations
(original exposure) ................... 2-45
3.4.1 Book Mode, 1 Original,
Copyboard Closed ............. 2-45
3.4.2 Book Mode, 1 Original,
Copyboard Cover Open ..... 2-46
3.5 Enlargement/Reduction
(zoom) ...................................... 2-47
3.5.1 Changing the Reproduction
Ratio in Main Scanning
Direction ............................ 2-47
3.5.2 Changing the Reproduction
Ratio in Sub Scanning
Direction ............................ 2-47
3.6 Scanner Drive System .............. 2-48
3.6.1 Outline ............................... 2-48
3.6.2 Controlling the Scanner
Motor ................................. 2-49
3.7 Controlling the Scanning
Lamp (LA101) ......................... 2-51
3.7.1 Outline ............................... 2-51
3.7.2 Scanning Lamp .................. 2-51
3.7.3 Turning On/Off
the Lamp ............................ 2-51
3.7.4 Detecting an Error ............. 2-52
3.8 Detecting the Size of
Originals ................................... 2-53
3.8.1 Outline ............................... 2-53
3.8.2 Points of Detection ............ 2-53
3.8.3 Outline of Detection .......... 2-53
3.9 Disassembly/Assembly
(iR7200) ................................... 2-57
3.9.1 Removing the Reader
Unit .................................... 2-58
3.9.2 Removing the Scanning
Lamp .................................. 2-59
3.9.3 Points to Note
When Replacing
the Scanning Lamp ............ 2-60
3.9.4 After Replacing
the Scanning Lamp ............ 2-61
3.9.5 Removing the Scanner
Motor ................................. 2-61
COPYRIGHT© 2001 CANON INC.
3.9.6 Mounting the Scanner
Motor ................................. 2-
3.9.7 Removing the Scanner
System Drive Cable ........... 2-
3.9.8 Routing the Scanner Drive
Cable .................................. 2-65
3.9.9 Positioning the No. 1/2
Mirror Base ........................ 2-66
3.9.10 Removing the Original
Size Sensor ........................ 2-68
3.9.11 Removing
the HP Sensor .................... 2-68
3.9.12 Removing the Copyboard
Cover Sensor ...................... 2-69
3.9.13 Removing the Fuse PCB ... 2-70
3.9.14 Removing the Inverter
PCB .................................... 2-71
4 Outline of the Image Processing
System (iR8500) ............................... 2-73
4.1 Outline ..................................... 2-73
4.2 Changes to the Image
Processing System ................... 2-74
4.3 4-Channels High-speed
CCD ......................................... 2-75
4.4 CCD Adjustment ...................... 2-76
4.5 Analog Image Processing ........ 2-77
4.6 Digital Image Processing ......... 2-78
4.7 Detecting the Orientation of
Originals ................................... 2-79
4.8 Disassembly/Assembly
(iR8500) ................................... 2-80
4.8.1 CCD Unit ........................... 2-81
4.8.2 Hard Disk ........................... 2-83
5 Image Processing System
(iR7200) ............................................ 2-86
5.1 Outline ..................................... 2-86
5.2 Analog Image Processing ........ 2-87
5.2.1 Outline ............................... 2-87
5.2.2 Driving the CCD ................ 2-87
5.2.3 Gain Correction and Offset
Correction of the CCD
Output ................................ 2-88
5.2.4 A/D Conversion of
the CCD Output ................. 2-88
CANON iR8500/7200 REV.1 AUG. 2001
CONTENTS
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