Ricoh C211 Service Manual page 105

4. TEST PATTERN IMAGE MODE
The purpose of this mode is to distinguish whether the cause of the image
problem is located before or after the image processing.
Output image: The normal output of this test pattern image mode is one
of the Dither matrix pattern as illustrated below.
Master processing length:
Main scan (Horizontal) direction: Full width of the thermal head
Sub scan (Vertical) direction:
Same as the vertical size of
the original set on the original
table.
Magnified Test Pattern Image
/
Test Pattern in Test Pattern in
Test Pattern Image
Line Mode Photo Mode
Em
(VT2300/VT2500
only)
Fhroresctm Lamp
Cco
m Commrsiorl
- +
Image
Processing PCB
–EiERszi
EEizl "
EiiEEl
This test pattern is generated by the image processing PCB.
[Example] Problem:
Possible Cause 1
Possible Cause 2
Vertical white lines appear on the print.
If the same problem appears on the output
Image from the thermal head in Test Pattern
image mode, the cause should exist in area
B as shown above.
If the output image from the thermal head is
correct in Test Pattern Mode but the output
image in the normal mode is incorrect, the
cause should exist in area A as shown
above.
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