Image Stabilizaton Control; Overview Of The Image Stabilization Control Mechanism; Image Density Correction Control (D-Max Control) - Canon LBP5050 Series Service Manual
2.4.3.1 Overview of the Image Stabilization Control Mechanism
LBP5050N / LBP5050
The machine uses its image stabilization control mechanism to prevent lowering of image quality (e.g., in the form of a faulty image) otherwise caused by changes
in the environment or deterioration of the photosensitive drum or toner.
The machine's image stabilization control mechanism may be any of 3 types: Image density corrective control (D-max control), Image halftone corrective control
(D-half control), Color Misregistration Corrective Control.
2.4.3.2 Image density correction control (D-max control)
LBP5050N / LBP5050
This control is to stabilize the image density of the printer engine.
If the prescribed condition is met, DC controller PCB performs D-max control in the following procedure.
1. Measure the each density detection pattern made on the ITB.
2. According to the measured density of each pattern, controls the primary charge bias and developing bias to get the appropriate density.
The following is the conditions that trigger the image density correction control
- When the power is ON
- When replacing the toner cartridge
- After replacing the toner cartridge, when the number of print exceeds the specified number (per 200 sheet)
- When the environment is changed drastically
- After printing, the specified time (300 min) elapses