Operation; Document Density Measurement System; Outline - Canon NP6320 Service Manual

CHAPTER 4 IMAGE FORMATION SYSTEM
V. DOCUMENT DENSITY MEASUREMENT SYSTEM
A.

Outline

There is an automatic density adjustment (AE) system which adjusts the DC component of the
developing bias to suit the density of the original. If the density of the original is more or less
uniform, the AE function varies the DC component of the developing bias to suit the density of the
original, so that copies of the correct density will be made.
B.

Operation

The scanner moves forward approximately 70 mm past the leading edge of the original and
stops momentarily. The scanning lamp goes ON for approximately one second, the image density
is read by the AE sensor, and the sensor output is interpreted by the DC controller. The DC control-
ler then adjusts the DC component of the developing bias accordingly.
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COPYRIGHT © 1999 CANON INC.
Approx. 65mm
Approx.
30mm
Approx.
Approx.
30mm
70mm
A
Approx.
28mm
Note:
Approx. Approx.
A is the position of the AE sensor
25mm 25mm
Figure 4-501
B5 A4
For reference: B6 size
CANON NP6320 REV.0 DEC. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)