Outline Of Detection; Book Mode, 1 Original, Copyboard Cover Open - Canon ImageRunner iR8500 Series Service Manual

Chapter 5
<AB-Configuration>
<Inch-Configuration

5.3.4.5 Outline of Detection

/ iR8070
The machine identifies the size of originals in the following two steps:
[1] Detecting External Light (main scanning direction only)
While keeping the scanning lamp off, the CCD level at each point of detection in main scanning direction is measured. A point at which external light is
detected will be identified as indicating the absence of an original, enabling the identification of the width of an original.
[2] Detecting the Sensor Output Level
The scanning lamp is turned on, and the CCD level at each point of detection in main scanning direction is measured. In addition, the reflection type
photosensor in sub scanning direction is turned on to measure the sensor output.
The combination of these output measurements is used to identify the size of the original.
For specific movements, see the pages that follow.

5.3.4.6 Book Mode, 1 Original, Copyboard Cover Open

/ iR8070
[1] The scanner remains in wait.
No. 1 mirror base: at HP
Xenon lamp: off
Original sensor: disabled
[2] The copyboard is opened.
Detection starts of external light in main scanning direction.
No. 1 mirror base: to point of original de-tection
Xenon lamp: off
Original sensor: disabled
5-22
Original sensor
Point of original
detection 1 B5R
Point of original
A4R
detection 2
Point of original
B5
detection 3
Point of original
A4
detection 4
Point of CCD original detection
F-5-34
Point of original
LTRR
detection 1
Point of original
LTR
detection 2
Point of CCD original detection
F-5-35
Point of original detection 1
Copyboard cover
Point of original detection 2
Point of original detection 3
Point of original detection 4
Reader unit
Point of original detection
F-5-36
B4
A3
Original sensor
LGL
279.4×431.8mm
(11"×17")
Original sensor
Copyboard glass
0008-7413
0008-7414