Service manual

T
echnical
B
ulletin
PAGE: 2/2
Model:
Bellini-C2 Date: 28-Aug-03 No.: RB070023
LD Unit Adjustment Procedure
Please perform the following if the spacers attached to the bottom of the LD unit are
misplaced or their original positions become unclear at LD unit replacement. This
adjustment is necessary to ensure ID variations along the main scan direction do not occur,
which result from beam pitch variations along the sub-scan direction.
Important:
Always make sure to turn the machine main power
OFF
before inserting the
spacers into the LD unit.
1. Print out the SP2902-3 No.22 test pattern without any Mylar spacers attached.
Perform the following two steps until the ID variation along the main scan direction is not
visible on the test chart:
2. Attach one 100μm (milk white) spacer in the rear of the unit. Print out the pattern
again and compare with the sample from Step 1.
! If the ID variation along the main scan direction decreases (improves) but is still
visible, attach another 100μm spacer in the same position.
! If the ID variation gets worse, go on to Step 3.
3. Attach one 100μm spacer in the
front
of the unit. Print out the pattern again and
compare this with the sample from Step 2.
! If the ID variation along the main scan direction decreases (improves) but is still
visible, attach another 100
μ
m spacer in the same position.
Rear
Front