Enlargement/Reduction; Magnification Change In Vertical Scan Direction; Magnification Change In Horizontal Scan Direction; Detecting The Size Of Originals - Canon iR2020 Series Service Manual

Chapter 4

4.3.3 Enlargement/Reduction

4.3.3.1 Magnification Change in Vertical Scan Direction

iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i
In the Book mode or when the ADF is used
In the vertical scan direction, the image is read at 100%. Magnification is changed by processing data on the image processor PCB.

4.3.3.2 Magnification Change in Horizontal Scan Direction

iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i
In the horizontal scan direction, magnification is changed as follows depending on the selected magnification rate:
1) When magnification is reduced to 50-99%
a. In the Book mode
Data is processed on the image processor PCB with the original scan speed held at 118 mm/sec.
b. When the ADF is used
The original feed speed is changed within the range of 118 mm/sec to 236 mm/sec depending on the selected magnification rate. Data is not processed on the image
processor PCB.
2) When magnification is increased to 100-200%
The original scan speed (in the Book mode)/original feed speed (when the ADF is used) is changed within the range of 118 mm/sec to 59 mm/sec depending on the
selected magnification rate. Data is not processed on the image processor PCB.

4.3.4 Detecting the Size of Originals

4.3.4.1 Outline

iR2016J / iR2016 / iR2020 / / iR2016i / iR2020i
The original size is identified by the combination of presence and absence of output levels of the reflection type sensors as summarized in the tables below.
- Absence of paper: The light reflected from the reflection type sensor changes when the copyboard cover is open/close.
- Presence of paper: The light reflected from the reflection type sensor does not change when the copyboard cover is open/close.
This machine is provided with the following sensors. Locations of the sensors are shown below.
- Vertical scan direction: Reflection type photo sensors (2 locations for AB; 1 location for Inch)
- Horizontal scan direction: Reflection type photo sensors (2 locations for AB; 2 locations for Inch)
4-8
AB-Configration
Horizontal scan direction
Upper left corner
of original
Original sensor 1
Original sensor 2
Inch-Configration
Horizontal scan direction
Upper left corner
of original
Original sensor 1
Index plate
Original sensor 3
Original sensor 4
B5R
A4R
B5
B4
A4
Original sensor 3
Original sensor 5
STMT-R
LTR-R LGL
LTR 11" 17"
F-4-15
A3
0010-4253
0010-4254
0010-4255