Canon NP6012 Service Manual page 86

2. Operation
To measure the density of an original, the scanning lamp is turned on at a specific intensity
to expose the original during initial rotation with the scanner at the home position.
The microprocessor on the DC controller PCB checks the AE signal four times, and aver-
ages the measurements to compute the developing DC bias which best matches the averaged
density of the original; it then sends the developing DC bias signal and the developing DC bias
on signal to the microprocessor on the composite power supply PCB.
20mm 28mm
(approx.)| (approx.)
>
Center of image _
56 mm
(approx.)
KAN: AE sensor reading area
Figure 3-323
3. Basic Sequence of Operations (AE measurement)
Copy Start key
ON
Main motor (M1)
Scanner motor (M2)
Scanning lamp (FL1}
AE sensor input
Figure 3-324
COPYRIGHT © 1995 CANON INC. CANON NP6O12/NPS012F/NP6212 REV.1 SEPT. 1995 PRINTED IN JAPAN (IMPRIME AU JAPON} 3-41