Canon MF735C Series Service Manual page 40

Cartridge
Bias
Execution Condition/Timing
Correction controls are performed under the following conditions:
Execution timing
At power-on
When the Toner Cartridge is replaced
When the environment (temperature) changes
After printing the specified number of pages
After the specific period of time has passed
When recovering from sleep mode (8 hours or more)
When [Full Adjust] is executed
When [Quick Adjust] is executed
When [Adjust Copy Image] is executed
When [Correct Print Color Mismatch] is executed
Description
Image Density Correction Control (D-max control)
It is performed to stabilize the image density of the printer.
The DC Controller corrects the primary charging bias and developing bias values.
Image Gradation Correction Control (D-half control)
It is performed to stabilize the image gradation of the printer.
The Main Controller performs gradation adjustment based on the measurement results of the halftone density performed by
the DC Controller.
Color Displacement Correction Control
Color displacement that occurs due to the individual differences of the Laser Scanner Unit and Toner Cartridge is corrected.
The Main Controller performs the following color displacement corrections by controlling the video signal based on the color
displacement information measured by the DC Controller.
• Write-start position in the horizontal scanning direction
• Horizontal scanning magnification ratio
• Write-start position in the vertical scanning direction
Auto Gradation Adjustment Control
It is performed to stabilize the gradation density characteristics of the image.
Laser scanner unit
ITB unit
High-voltage
power supply PCBs
DC controller
Auto-gradation
D-max
correction control
Reader unit
D-half
31
2. Technical Explanation (Device)
Color displacement
/density sensor
Signal from color displacement
/density signal
Color displacement
correction control
Main controller
D-max D-half
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
Yes Yes
-
Video signal
Color displacement
correction
Yes
Yes
Yes
Yes
Yes
-
-
-
-
- Yes