Ricoh A085, Manual

Page: 296 / 617

5.2 LEAD EDGE AND TRAIL 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 on
the drum (lead edge erase margin). This prevents the ID sensor pattern and
the V
L
pattern from being developed every copy cycle. It also prevents the
shadow of the original lead edge from appearing on the copy paper. This
lead erase margin is also necessary for the lead edge of the copy paper to
separate from the hot roller. The width of the lead edge erase margin can be
adjusted by SP mode #41.
When the scanner reaches the return position, the charge corona, the grid
bias, and the exposure lamp turn off. However, the charged area on the drum
surface is a little longer than the actual original length in order to have the
entire latent image of the original.
The entire line of LEDs turn on when the trail edge of the latent image has
passed by 2 mm under the erase lamp unit. This prevents developing
unnecessary parts of the drum surface, reducing toner consumption and
drum cleaning load.
The LEDs stay on to erase the lead edge of the latent image in the next copy
cycle. After the final copy, the erase lamps turn off at the same time as the
main motor.
Normally, there is no trail edge erase margin on copies. But we can make a
trail edge erase margin using SP mode #157, if necessary (see
troubleshooting section).
Det
a
il
ed
Descriptions
12 February 1992 ERASE
2-41