Epson AcuLaser C1900 Service Manual page 94

EPSON AcuLaser C1900/AcuLaser C900
Laser light adjustment control
Adjusts the quantity of laser light to ensure a constant black and white lines
reproducibility and a constant amount of toner consumed relative to environmental
variations and change with the lapse of time in photoconductor characteristics,
development characteristics or electric change characteristics.
Gamma correction control
Forms a pattern on the transfer belt, measures the density of the pattern with the
AIDC sensor and sends the measurement result to the controller for correction of
pixel depth.
Timing for control operation
In the image stabilization control, each control item is executed as required depending on
the circumstances.
Table 2-6. Operation Timing
Timing for Control Operation
At detection of new intermediate A
transfer belt
At detection of new Photoconductor
Unit/Toner Cartridge
At environmental change
*1
After 1000-sheet printing
*2
After 200-sheet printing B
At indication by controller C
Note "*1": When 1000 sheets or more have been printed since the previous processing of A was
executed.
"*2": When 200 sheets or more have been printed since the previous processing of A or B
was executed.
Operating Principles
Processing
→
Ds correction control LED light adjustment
control
→ →
Belt surface level correction control
color toner adhesion control
→ →
Laser light adjustment control Gamma
correction control
→
Solid color toner adhesion control Laser light
adjustment control
→
Gamma correction control
Gamma correction control
Image Stabilization Control
Temperature/humidity sensor
The output voltage is determined from the value calculated by ATVC control and the value
(environment) detected by the temperature/humidity sensor.
Temperature/humidity
sensor (HS1)
Solid
Revision B
Temperature
data
ATVC control
Humidity
data
Main Board Assy (PWB-A)
High Voltage Unit (HV)
Secondary Transfer Bias
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