Canon CLBP-460PS, Руководство по обслуживанию

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1. Electrostatic latent image formation block
This block has two steps which together produce a pattern of electrical charges on the photo-
sensitive drum.
At the end of the block, negative charges remain in the unexposed “dark” areas. Charges are
absent from “light” areas, where the laser beam struck (exposed) the drum surface.
Since this image of negative charges on the drum is invisible to the eye, it is called an “elec-
trostatic latent image”.
Figure 2-4-19
Step 1 Primary charge
For preparation of latent image formation, a uniform negative potential is applied to the photo-
sensitive drum surface. The printer uses the charging method that directly charges the drum
for primary charge.
In addition to DC bias, AC bias is applied to the primary charging roller to keep the potential
on the drum surface uniform.
Figure 2-4-20
2 - 63
CHAPTER 2
0
-100
-500
Time (t)
Surface
potential
(V)
Exposed area
Unexposed
area
Scanning
exposure
(step 2)
Primary
transfer
(step 4)
Primary
charge
(step 1)
Primary
charge
(step 1)
Photosensitive drum
Primary charging roller
AC bias
DC bias