Adjusting The Density During Printing (Pdl Input) - Canon ImageRunner 600 Service Manual

1.

Adjusting the Density during Printing (PDL input)

The laser power is increased
(to increase the contrast),
thereby enabling reproduction
of fine lines narrower than a
single particle of toner.)
Potential sensor
Laser
Grid bias
Potential determined
Related Service Mode
COPIER>OPTION>BODY>
CNT-W/PR
(density setting mode on/off during
printing)
Main power switch
Set
OFF/ON
COPIER > OPTION > BODY > CNT-W/PR
COPYRIGHT © 1999 CANON INC.
Lighter
Density
Darker
The laser power/developing
bias is corrected to suit the F
value setting.
Potential control
sequence started
195˚C
WMUPR
WMUP
VD
Vg
Vg
Figure 6-211 Sequence of Operations
1: correct the target value to enable variation of density
during printing. (default)
0: disable the mechanism used to vary the density during
printing.
Potential Printing
control started
Table 6-202 Timing of Control
CANON imageRUNNER 600 REV.1 JAN. 2000 PRINTED IN U.S.A.
CHAPTER 6 IMAGE FORMATION SYSTEM
Laser power
F value
correction
value
1
x0.8
2 x0.9
3 x1.0
4
x1.1
5
x1.2
x1.3
6
7 x1.4
x1.5
8
9
x1.5
The laser power has
reached the upper limit,
requiring correction of
the developing bias to
increase the contrast.
VL
Pw
Pw Vdc
A laser power output Vdc
suited to the F value setting
is used.
F value
changed
VD
Vdc
correction
correction
value
value
+10V
+20V
+30V
+40V
200˚C
STBY
6-13