Olivetti d-Color MF550, Теория работы

Страница: 44 / 188

Theory of Operation Ver. 8.0 Jun. 2008 8. Write section (PH section)
3
5
Composition/Operation
A. Color shift correction method
• Black (K) is used as a standard of reference when other colors, yellow (Y), magenta (M),
and cyan (C), are individually corrected.
(1) Color shift in the main scanning direction
• The following two methods are available to correct color shift in the main scanning direc-
tion.
1. Adjustment in the main scanning direction: Change of image write start timing in
the main scanning direction.
2. Overall scaling: Change of writing clock frequency.
(2) Color shift in the sub scanning direction
1. Adjustment in the sub scanning direction: Change of image write start timing in the
sub scanning direction.
2. Color skew correction:
Adjustment of the PH unit G3 lens skew.
The G3 lens is driven by the skew correction motor.
• For an easier explanation, the above illustration uses the relation between black toner (K)
and color toners (Y, M, C) that are transferred onto the transfer belt.
B. Color registration control operation timing
The color registration control and the image stabilization control operate at one time. For
detail, refer to the image stabilization control section.
Color shift by inappropriate
scaling Color shift in the main scanning
direction
K
Y,M,C
Y,M,C
K
The direction in
which the transfer
belt moves The direction in
which the transfer
belt moves
K
Y,M,C
Color shift in the sub scan-
ning direction
K
Y,M,C
Color skew
The direction in
which the transfer
belt moves The direction in
which the transfer
belt moves
Y107522-3 Theory of Operation