Canon ImageRunner iR8500 Series, Service Manual, Page: 14 / 1122

Contents
5.4.13.2
Removing the Original Size Sensor 1/2 ............................................................................................................................... 5- 44
5.4.13.3 Removing the Original Size Sensor ..................................................................................................................................... 5- 44
5.4.13.4 Removing the Original Size Sensor 3/4 ............................................................................................................................... 5- 44
5.4.13.5 Removing the Original Size Sensor 3/4 ............................................................................................................................... 5- 45
5.4.14 Scanner Home Position Sensor ...........................................................................................................................5- 45
5.4.14.1 Removing the HP Sensor..................................................................................................................................................... 5- 45
5.4.14.2 Removing the Scanner Home Position Sensor.................................................................................................................... 5- 45
5.4.14.3 Removing the Scanner Home Position Sensor.................................................................................................................... 5- 46
5.4.15 Copyboard Glass Sensor .....................................................................................................................................5- 46
5.4.15.1 Removing the Copyboard Glass Sensor.............................................................................................................................. 5- 46
5.4.15.2 Removing the Copyboard Glass Sensor.............................................................................................................................. 5- 46
5.4.16 Image Leading Edge Sensor................................................................................................................................5- 47
5.4.16.1 Removing the Image Leading Edge Sensor ........................................................................................................................ 5- 47
5.4.16.2 Removing the Image Leading Edge Sensor ........................................................................................................................ 5- 47
5.4.17 Scanner Drive Cable ............................................................................................................................................5- 47
5.4.17.1 Adjusting the Tension of the Scanner Drive Cable .............................................................................................................. 5- 47
5.4.17.2 Adjusting the Tension of the Scanner Drive Cable .............................................................................................................. 5- 49
5.4.17.3 Removing the Scanner System Drive Cable........................................................................................................................ 5- 50
5.4.17.4 Removing the No. 1 Mirror Case Flexible Cable.................................................................................................................. 5- 50
5.4.17.5
Removing the No. 1 Mirror Case Flexible Cable.................................................................................................................. 5- 51
5.4.17.6 Routing the Scanner Drive Cable......................................................................................................................................... 5- 52
5.4.17.7 Positioning the No. 1/2 Mirror Base ..................................................................................................................................... 5- 53
Chapter 6 Image Processing System
6.1 Outline ........................................................................................................................................................ 6- 1
6.1.1 Outline of the Image Processing System.................................................................................................................6- 1
6.1.2 Outline......................................................................................................................................................................6- 1
6.2 Analog Image Processing .......................................................................................................................... 6- 2
6.2.1 Analog Image Processing ........................................................................................................................................6- 2
6.2.2
Outline......................................................................................................................................................................6- 2
6.2.3 Driving the CCD .......................................................................................................................................................6- 3
6.2.4 Gain Correction and Offset Correction of the CCD Output ......................................................................................6- 3
6.2.5 A/D Conversion of the CCD Output .........................................................................................................................6- 3
6.2.6 4-Channel High-Speed Reading CCD .....................................................................................................................6- 3
6.2.7
CCD Adjustment ......................................................................................................................................................6- 4
6.3 Digital Image Processing............................................................................................................................ 6- 5
6.3.1
Digital Image Processing .........................................................................................................................................6- 5
6.3.2 Outline......................................................................................................................................................................6- 5
6.3.3 Detecting the Orientation of Originals ......................................................................................................................6- 5
6.3.4 Shading Correction ..................................................................................................................................................6- 6
6.3.5 Auto Density Adjustment (AE) .................................................................................................................................6- 7
Chapter 7 Laser Exposure
7.1
Construction ............................................................................................................................................... 7- 1
7.1.1
Outline of the Laser Exposure System ....................................................................................................................7- 1
7.1.2 Outline of the Laser Exposure System ....................................................................................................................7- 1
7.2 Basic Sequence ......................................................................................................................................... 7- 3
7.2.1
Basic Sequence of Operations (laser exposure system) .........................................................................................7- 3
7.2.2 Basic Sequence .......................................................................................................................................................7- 3
7.3 Various Controls......................................................................................................................................... 7- 4
7.3.1 Controlling the Laser Activation Timing ...................................................................................................................7- 4
7.3.1.1 Flow of the BD Signal .............................................................................................................................................................. 7- 4
7.3.2 Controlling the Intensity of Laser Light.....................................................................................................................7- 4
7.3.2.1 Outline...................................................................................................................................................................................... 7- 4
7.3.2.2 Controlling Laser Activation ..................................................................................................................................................... 7- 5
7.3.2.3 Controlling the Laser Intensity ................................................................................................................................................. 7- 6