Canon iR3570 Series, Service Manual

Page: 199 / 722

Chapter 5
5-9
-if the setting of CCD-LUT is other than '0' and you have replaced the reader controller PCB.
<Service Mode>
for CIS unit gain correction data
COPIER>OPTION>BODY>CCD-LUT
for CCD gain correction
5.3.3 Enlargement/Reduction
5.3.3.1 Changing the Magnification in Main Scanning Direction
0006-5724
iR2270 / iR2870 / iR3570 / iR4570 / / iR2270N / / iR2870N / / iR3570N / / iR4570N / iR2230 / / / iR3530 /
In Book Mode/ADF Mode
The image is read at 100% in main scanning direction, and the magnification is varied by processing the data on the main controller PCB.
5.3.3.2 Varying the Magnification in Sub Scanning Direction
0006-5725
iR2270 / iR2870 / iR3570 / iR4570 / / iR2270N / / iR2870N / / iR3570N / / iR4570N / iR2230 / / / iR3530 /
To vary the magnification in sub scanning direction, the machine operates as follows depending on the selected method of reading the original and the selected rate
of magnification:
1. In Book Mode
To suit the selected rate of magnification, the speed at which the original is read is varied and the data is processed by the reader controller PCB/main controller PCB.
EX: for reduction to 25%, the original is read at 236 mm/sec and the data is varied for 50% reduction by the reader controller PCB (skipping data for 1/2) and for
50% reduction by the main controller PCB (skipping data for 1/2).
EX: at 100%, the original is read at a speed of 236 mm/sec.
T-5-5
2. In ADF Mode
To suit the selected rate of magnification, the speed at which the original is read is varied and the data is processed by the reader controller PCB/main controller PCB.
EX: for reduction to 25%, the original is read at 236 mm/sec, and the data is processed for 50% reduction (skipping for 1/2) by the reader controller PCB and for
50% (skipping for 1/2) by the main controller PCB.
EX: for enlargement to 400%, the original is read at a speed of 118 mm/sec, and the data is processed for 200% enlargement (doubling) by the main control PCB.
T-5-6
5.3.4 Detecting the Size of Originals
5.3.4.1 Outline
0006-5731
iR2270 / iR2870 / iR3570 / iR4570 / / iR2270N / / iR2870N / / iR3570N / / iR4570N / iR2230 / / / iR3530 /
The machine identifies the size of the original with reference to the presence/absence of output levels of the reflecting type sensors; specifically,
-the machine identifies the absence of paper if it finds a change in the output of the reflection type sensors when the copyboard cover is closed/opened.
-the machine identifies the presence of paper if it does not find a change in the output of the reflection type sensors when the copyboard cover is closed/opened.
The machine uses the following sensors; and the sensors are arranged as shown in the following figure:
-for main scanning direction, reflection type photosensors (AB-configuration, 2 locations; Inch-configuration, 1 location).
-for sub scanning direction, reflection type photosensors (AB-configuration, 2 locations; Inch-configuration, 2 locations)
Operation
Magnification
25% to 49% 50% to 99% 100% to 400%
Varying the speed of reading the original (mm/
sec)
236 to 120 236 to 119 236 to 59
Processing the data (digital; %) by the reader
controller PCB
50 50 100
Processing the data (digital; %) by the main
controller PCB
50 100 100
Operation
Magnification
25% to 42% 43% to 84% 85% to 170% 171% to 400%
Varying the speed at which the original is read
(mm/sec)
236 to 168 274 to 140 277 to 139 276 to 118
Processing the data (digital; %) by the reader
controller PCB
50 50 100 100
Processing the data (digital; %) by the main
controller PCB
50 100 100 200