COPYRIGHT © 1998 CANON INC. CANON PC400/420/430,FC200/220 REV.0 JAN.1998 PRINTED IN JAPAN (IMPRIME AU JAPON)
4-14
CHPTER 4 IMAGE FORMATION SYSTEM
F. Document Density Measurement (AE; PC420/430/FC220)
1. Outline
The copier is equipped with an automatic density control (AE) mechanism that
controls the DC component of the developing bias. The copier’s AE mechanism does
not execute an AE scan, but instead measures the document density during image
exposure.
2. Operations
Document measurement is started while the copyboard is moving forward; i.e.,
when the leading edge of the document begins to be exposed (copyboard position
sensor Q902 goes OFF).
At the time, the photodiode (PD602) checks the reflected light.
The output of the photodiode (PD602) is amplified, and sent to the microprocessor
as AE signals.
<AE Measurement Timing Chart>
Figure 4-101F
Sequence
Copyboard
1
2
3
4
STBY
INTR
CBRV STOP
COPY
CBFW
Power switch ON
Main motor
(M1)
Copyboard position
sensor (Q902)
AE
measurement
Developing
DC bias
Copy Start key ON
Содержание FC200
Страница 10: ...COPYRIGHT 1998 CANON INC CANON PC400 420 430 FC200 220 REV 0 JAN 1998 PRINTED IN JAPAN IMPRIME AU JAPON viii ...
Страница 197: ...PRINTED IN JAPAN IMPRIME AU JAPON 0198M2 01 1 This publication is printed on 70 reprocessed paper ...
Страница 244: ...PRINTED IN JAPAN IMPRIME AU JAPON ...
Страница 250: ...COPYRIGHT 1998 CANON INC CANON PC400 420 430 FC200 220 REV 0 JAN 1998 PRINTED IN JAPAN IMPRIME AU JAPON iv ...
Страница 267: ...CHAPTER 3 IMAGE TROUBLESHOOTING 3 5 ...
Страница 268: ...3 6 CHAPTER 3 IMAGE TROUBLESHOOTING B Samples of Image Faults not available ...
Страница 276: ...3 14 CHAPTER 3 IMAGE TROUBLESHOOTING ...
Страница 306: ...PRINTED IN JAPAN IMPRIME AU JAPON 0198M2 01 1 This publication is printed on 70 reprocessed paper ...