Canon imageRUNNER ADVANCE 6055 Series, Руководство по обслуживанию

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Technology > Image Formation System > Controls > Auxiliary Control
Technology > Image Formation System > Controls > Auxiliary Control
Lp_after Lp_before
VL (V)
VL
VL0re
Procedure 1), 2)
Procedure 3)
Bright area potential
characteristics( )
B. Initial rotation APC control
1) Bright area potential VL is measured during initial rotation to correct laser power. The
primary current value and developing bias value are fi
2) Correction is executed by following the same way as between-sheet APC control.
C. Last rotation APC control
This correction follows the same way as initial rotation APC control
F-2-105
● Two Dimension Shading Control
Uneven potential on the Photosensitive Drum is corrected by laser exposure.
Execution timing
At the time of laser exposure (only when the two dimension shading control is ON. Default:
OFF)
Control description
1) Potential data on the Drum surface is saved in EEPROM on the DC Controller PCB
in the format supporting two-dimension coordinate (measured when the Drum was
manufactured).
2) When the power is turned ON, EEPROM data is compared to RAM data. If there is any
difference in the data, the EEPROM data is stored in the backup RAM.
NOTE:
Whether the control is enabled can be checked with COPIER>DISPLAY>2D-SHD>2D-
STS.
If 0 is displayed, check DRM-LOT number. When 0 is displayed, it means that the drum
has not been registered; thus, execute FUNCTION/2D-SHADE/2D-READ to register
the drum.
3) Potential data on the Drum surface is sent to the image ASIC and the image data is
synchronized with the Drum home position, and then the uneven potential data is converted
into light intensity to be sent to the Laser Driver PCB.
4) The Laser Driver PCB is exposed to remove uneven potential on the Drum.
NOTE:
For Drum provided as a service part, EEPROM which stores potential unevenness data
is included. Therefore, the EEPROM needs to be replaced when the Drum is replaced.
As the life of the Drum advances, uneven density can occur when the halftone image
is output despite correction of the drum uneven potential. In such a case, uneven
density can be corrected by specifying a particular position in service mode. See
Troubleshooting for procedure.
FCOT (First Copy Time) is reduced to detect home position of the Drum by turning ON
the two dimension shading.