Canon iR3245, Service Manual

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Contents
5.3.5.1
Overview ................................................................................................................................................................................ 5- 15
5.3.5.2 White Board Dust Detection Control ...................................................................................................................................... 5- 17
5.3.6
Image Processing.................................................................................................................................................. 5- 18
5.3.6.1 Overview ................................................................................................................................................................................ 5- 18
5.3.6.2
CCD Drive.............................................................................................................................................................................. 5- 18
5.3.6.3 Gain Correction and Offset Correction of CCD Output .......................................................................................................... 5- 18
5.3.6.4
A/D Conversion of CCD Output ............................................................................................................................................. 5- 19
5.3.6.5 Shading Correction (overview)............................................................................................................................................... 5- 19
5.3.6.6 Shading Adjustment............................................................................................................................................................... 5- 19
5.3.6.7
Shading Correction ................................................................................................................................................................ 5- 19
5.4
Parts Replacement Procedure .................................................................................................................5- 20
5.4.1 CCD Unit ............................................................................................................................................................... 5- 20
5.4.1.1 Removing the CCD Unit......................................................................................................................................................... 5- 20
5.4.1.2
When Replacing the CCD Unit .............................................................................................................................................. 5- 21
5.4.2
CCD Cover Unit ..................................................................................................................................................... 5- 21
5.4.2.1
Removing the CCD Cover Unit .............................................................................................................................................. 5- 21
5.4.3 Copyboard glass.................................................................................................................................................... 5- 21
5.4.3.1
Removing the Copyboard Glass ............................................................................................................................................ 5- 21
5.4.3.2 When Replacing the Copyboard Glass .................................................................................................................................. 5- 22
5.4.3.3
Removing the ADF Reading Glass ........................................................................................................................................ 5- 23
5.4.3.4 When Replacing the ADF Reading Glass .............................................................................................................................. 5- 23
5.4.4 Reader Controller PCB .......................................................................................................................................... 5- 24
5.4.4.1 Points to Note Before Replacing the Reader Controller PCB ................................................................................................ 5- 24
5.4.4.2
Removing the Reader Controller PCB ................................................................................................................................... 5- 24
5.4.4.3 After Replacing the Reader Controller PCB........................................................................................................................... 5- 24
5.4.5 LED Driver PCB..................................................................................................................................................... 5- 25
5.4.5.1 Removing the LED Driver PCB.............................................................................................................................................. 5- 25
5.4.6 Scanner Motor ....................................................................................................................................................... 5- 25
5.4.6.1 Removing the Scanner Motor ................................................................................................................................................ 5- 25
5.4.7
Copyboard Cover Open/Close Sensor .................................................................................................................. 5- 25
5.4.7.1
Removing the Copyboard Cover Open/Closed Sensor (Front/Rear)..................................................................................... 5- 25
5.4.8
CCD HP Sensor .................................................................................................................................................... 5- 26
5.4.8.1
Removing the CCD Unit HP Sensor ...................................................................................................................................... 5- 26
5.4.9 Original Size Sensor.............................................................................................................................................. 5- 26
5.4.9.1
Removing the Original Size Sensor ....................................................................................................................................... 5- 26
5.4.10 Reader Heater (option) ........................................................................................................................................ 5- 27
5.4.10.1 Removing the Reader Heater (Right)................................................................................................................................... 5- 27
5.4.10.2 Removing the Reader Heater (Left) ..................................................................................................................................... 5- 27
Chapter 6 Laser Exposure
6.1
Construction ...............................................................................................................................................6- 1
6.1.1 Specifications/Controls/Functions ........................................................................................................................... 6- 1
6.1.2
Main Configuration Parts ......................................................................................................................................... 6- 1
6.1.3
Control System Configuration.................................................................................................................................. 6- 2
6.2 Basic Sequence..........................................................................................................................................6- 3
6.2.1
Basic Sequence....................................................................................................................................................... 6- 3
6.3 Various Controls .........................................................................................................................................6- 4
6.3.1 Controlling the Laser Activation Timing ................................................................................................................... 6- 4
6.3.1.1 Laser ON/OFF Control ............................................................................................................................................................. 6- 4
6.3.1.2
Main Scanning Synchronous Control....................................................................................................................................... 6- 5
6.3.2 Controlling the Intensity of Laser Light .................................................................................................................... 6- 5
6.3.2.1 APC Control ............................................................................................................................................................................. 6- 5
6.3.3 Controlling the Laser Scanner Motor ....................................................................................................................... 6- 6
6.3.3.1 Laser Scanner Motor Control................................................................................................................................................... 6- 6
6.3.4 Controlling the Laser Shutter................................................................................................................................... 6- 7
6.3.4.1 Laser Shutter Control ............................................................................................................................................................... 6- 7
6.4 Parts Replacement Procedure ...................................................................................................................6- 8
6.4.1
Laser Scanner Unit.................................................................................................................................................. 6- 8