Canon IR3300, IR2800, IR2200 Gain Correction and Offset Correction of the CCD Output, F03-205-01

CHAPTER 3 IMAGE PROCESSING SYSTEM

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.)

Decrease
Increase	Read start position
Original

Vertical size plate

F03-205-01

COPYRIGHT © 2001 CANON INC. CANON iR2200/iR2800/iR3300 REV.0 MAR. 2001 3-3 R