Ricoh B234 - Page 558

MAIN SERVICE PROGRAM MODE TABLES
B234/B235/B236/D101/D102/D103 5-20 SM
2115 Main Scan Beam Pitch Adjustment
A label attached to the LD unit service part lists the correct settings.
001 Pitch Adjustment Between LD0 and LD2 (LD0)
[-100~100 / 0 / 1 μm]
002 Pitch Adjustment Between LD0 and LD4 (LD0)
[-100~100 / 0 / 1 μm]
003 Pitch Adjustment Between LD0 and LD6 (LD0)
[-100~100 / 0 / 1 μm]
004 Pitch Adjustment Between LD1 and LD3 (LD1)
[-100~100 / 0 / 1 μm]
005 Pitch Adjustment Between LD1 and LD5 (LD1)
[-100~100 / 0 / 1 μm]
006 Pitch Adjustment Between LD1 and LD7 (LD1)
[-100~100 / 0 / 1 μm]
007 Pitch Adjustment Between LD0 and LD1 (Ch0 ~ Ch1)
[-99~99 / 0 / 1 μm]
008 Between LD0 and LD1 (Ch0 ~ Ch1 – Front Main Scan)
[-99~99 / 0 / 1 μm]
009 Between LD0 and LD1 (Ch0 ~ Ch1 – Rear Main Scan)
[-99~99 / 0 / 1 μm]
Two adjustments have been added to adjust:
• The timing of the clock that controls image writing in the sub scan direction
• The speed of the revolution of the polygon mirror motor that affects image writing
in the sub scan direction.
There are three new SP codes for laser beam pitch adjustment: SP2115 007, 008,
009. These new SPs are provided to correct errors in the rate of magnification from
the time the line scan starts until it ends.
The rate of the main scan magnification error is the amount of correction to be
done for the magnification rate based on the length of the distance in the main
scan direction for line end LD1 (ch1) with reference to line start LD0 (ch1). These
are the lengths of the distances "A" and "B" in the illustration below.
With SP2115 007 set to "0", there can be as much variation in the pitch as shown
above in the front area ("A") and the rear area ("B"). To correct this problem the
pitches of Area 1 and Area 2 can be adjusted independently with two SP codes.
SP2115 008 is used to adjust the pitch of Area 1. SP2115 009 is used to adjust the
pitch of Area 2.
Write Start
Write Finish
Laser Scan Direction
Paper Feed
Line Start (ch0)
Line End (ch1)
Beam
Center
Axis
AB
Synchronization
Area 0 Area 1 Area 2
Main Scan (Front) Main Scan (Back)
B234S903.WMF