Sharp SF-1120 - Manual (Page 36)

(Optical system dirt correction)
This model perform dirt correction by changing the copy lamp inten-
sity according to the dirt degree in the optical system (the copy lamp
unit, No. 1 mirror, No.2 mirror, No.3 mirror) to prevent against remark-
able degrading of copy quality.
The reference value is the AE sensor output value which is obtained
when the reference plate is exposed with the copy lamp voltage of
67.0V (134.0V) at power ON.
This value is checked with sim 44-08, 09.
(1) Setting the reference value for optical system correction.
1 Clean the optical system at every maintenance.
2 Perform Simulation 46-1.
(The previous data are cleared.)
3 After completion of Simulation 46-1, when performing the first
mirror initialization, measure light quantity of the copy lamp.
Obtain the average value from the four measurement values and
use the average value as the reference value for correction.
Obtain the average value of four AE sensor values, and store it.
(2) Dirt correction
1 Measure light quantity when performing mirror initialization.
2 Store the correction data into memory.
3 Reset the register inside the CPU.
Reference plate (Glass holder)
Table glass
Copy lamp light quantity "UP"
Automatic exposure
sensor
CPU
Reference value
>Measured value
Correction data output
100 200 300 400 79.8K 80K
CLV + (0.7)
Sim46
CLV
CL(V) = INI CL(V) + (0.33 x 2)
1step = (0.33 x 2)
Reference plate (Glass holder)
Table glass
Automatic exposure
sensor
CPU reference value
setting
CL
800ms
Light quantity
measurement
Copy lamp light quantity "UP"
CPU
Reference value
>Measured value
Correction data output
Reference plate (Glass holder)
Table glass
Automatic exposure
sensor
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