Canon IR2200, IR2800, IR3300 2.3 Gain Correction and Offset Correction of the CCD Output, 2.4 A/D Conversion of the CCD Output

COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON iR2200/iR2800/iR3300 REV.0 MAR. 2001
CHAPTER 3 IMAGE PROCESSING SYSTEM
3-3 R
2.3 Gain Correction and Offset Correction of the CCD Output
To correct discrepancies in the efficiency of photoconversion among pixels, the analog
video signals from the CCD are corrected: in gain correction, the rates of amplification are
standardized; in offset correction, on the other hand, the output voltage in the absence of in-
coming light is set to a specific level.
2.4 A/D Conversion of the CCD Output
The analog video signals of odd-number and even-number pixels after correction are con-
verted into 8-bit digital signals that correspond to specific pixel voltage levels by the A/D
converter.
COPIER/ADJUST>ADJ-XY>ADJ-Y (CCD read start position adjust-
ment)
It is used to adjust the parameter used determining the read start position in
main scanning direction.
Range: 0 to 400
(A change by ‘1’ results in a shift of 0.1 mm.)
F03-205-01
Decrease
Increase
Original
Vertical size plate
Read start position