Auxiliary Process; Blank Exposure - Canon NP6621 Service Manual

COPYING PROCESS
II. AUXILIARY PROCESS
A. Blank Exposure
Blank exposure is executed to remove the drum
surface potential of the non-image area that occurs
as a result of the difference among copy sizes or
when making copies in Reduce mode.
The light from the pre-exposure lamp is re-
flected by the reflecting plate and directed to the
photosensitive drum.
The non-image area between sheets of copy
paper is created by reflecting the light from the pre-
exposure lamp by a separate reflecting plate,
exposing the whole area.
Pre-exposure lamp Blank exposure
light path
Shutter
Reflecting plate
Pre-exposure
light path
Figure 2-201
2–8
Reflecting
plates
No. 6 mirror
Blank exposure light path
(for area between sheets)
Photosensitive drum
COPYRIGHT © 1998 CANON INC. CANON NP6621 REV.0 FEB. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)