Target Potential Correction In Each Mode - Canon imageRUNNER 7095 Service Manual

Chapter 7

7.4.9 Target Potential Correction in Each Mode

For the following, the machine corrects the laser power/developing bias determined as part of potential
control, using the result as the target value for the individual modes:
Density adjustment
during printing (PDL
input)
Density adjustment
during printing (scanner
input)
1. Adjusting the Density during Printing (PDL input)
Increases the laser power
(i.e., increasing the contrast)
to enable reproduction of fine lines,
each as wide as the diameter of a
single toner particle.
Potential sensor
Laser
Grid bias
Selected potential
SERVICE MODE:
- COPIER> OPTION> BODY> CNT-W/PR (enabling/disabling density variable mode during printing)
0: corrects the target value to permit variation of density during printing. (default)
1: does not permit variation of density during printing.
7-10
Purpose
To enable reproduction of fine lines suited to
the needs of the user (PDF data from a PC).
To enable a specific level of density suited to
the needs of the user.
Lighter
Density
Darker
Corrects the laser power/developing
bias to suit the F value setting.
Potential control
sequence started
193
WMUP WMUPR
VD
Vg
Vg
Main power switch
Set
OFF/ON
Potential
control
COPIER > OPTION > BODY > CNT-W/PR
T-7-2
Corrects the laser power/developing bias
to suit the F value setting.
Corrects the laser power/developing bias
to suit the F value setting
Laser power Vdc
F
correction correction
value
value value
1
0.6
2
0.7
3 0.8
4
0.9
5
1.0
1.1
6
7 1.2
1.2
8
+20V
9
1.2
+40V
The laser power reaches the upper limit,
causing the machine to correct the
developing bias and to increase the
contrast.
VL
Pw
Pw Vdc
F-7-14
A laser power output Vdc
suited to the F value setting
is used.
Printing
F value
started
changed
F-7-15
Correction
VD
correction
value
198
STBY
0010-8048