Specifications

4.1.1 Lead Edge Erase
The entire line of LEDs turns on when the main motor turns on. They stay on
until the erase margin slightly overlaps the lead edge of the original image
area on the drum (Lead Edge Erase Margin). This prevents the toner density
sensor pattern from being developed every copy cycle and the shadow of the
original edge from being developed on the paper. At this point, side erase
starts. The width of the lead edge erase margin can be adjusted using SP
mode #41.
During the image density detection cycle (once every ten copy cycles), a
block of erase lamps (labeled "h" above) turns off long enough for the sensor
pattern to be developed.
The entire line of LEDs turns on when the residual voltage on the OPC drum
is being detected (Vr correction).
4.1.2 Side Erase
Based on the combination of copy paper size and the reproduction ratio data,
the LEDs turn on in blocks (labeled "a" – "h" above). This reduces toner
consumption and drum cleaning load.
abcd e f g h f e d bac
1 December 1990
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