2.4 Print Position Adjustment
For instructions on how to perform the print position adjustments (Head position auto/
user), see
Part 3: 4.4 User Mode (page 3-43)
2.4.1 Automatic Print Position Adjustment
This printer is capable of automatically adjusting the vertical/horizontal positions of
the four BJ print heads installed on the carriage. It can also correct any print position
discrepancies between the printouts in both the forward printing and reverse printing
modes.
The procedure for automatic print position adjustment is as follows; first the carriage
prints an automatic print position adjustment pattern. Then the reflection density at
specified locations on the printed pattern are read by the print position sensor
(consisting of the LED and the photosensor) installed in the carriage. Next the position
calibration values are calculated by comparing the detected density values against the
theoretical values, and the horizontal position adjustment is performed according to
the calculated calibration values. For the vertical position adjustment, the vertical
position differences of the heads are detected using a black reference line which is
printed by the left side components of the print head during the forward carriage
travel, and from which the calibration values are calculated. Then the printer uses
these calibrated values to adjust the vertical/horizontal positions of the four BJ print
heads and correct any print position discrepancy between the printouts in the forward
and reverse printing operations.
Before the print position sensor takes the reflection density reading the printer
completes the sensor calibration process that matches the sensitivity of the LED to
the photosensor for three colors. The LED can emit three colors: red, green and blue.
The pattern printout in Y is identified with the blue light from the LED, M and PM
with the green light, and C, PC, and K with the red light.
Note that A1 or larger roll paper must be used for the automatic print position
adjustment.
4-11
Part 4: Technical Reference
BJ-W9000
Carriage unit
Left heads
Right heads
BJ Print Head C
BJ Print Head B
BJ Print Head A
BJ Print Head D
Nozzle
array
A
Nozzle
array
B
Nozzle
array
C
M
PM
Y
Y
PM
M
C
PC
K
K
PC
C
Nozzle
array
A
Nozzle
array
B
Nozzle
array
C
Nozzle
array
A
Nozzle
array
B
Nozzle
array
C
Nozzle
array
A
Nozzle
array
B
Nozzle
array
C
Figure 4-6 Left/Right BJ print heads
Содержание BJ-W9000
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