Olivetti d-Color MF550, Теория работы

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22. Image stabilization control Theory of Operation Ver. 8.0 Jun. 2008
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omposition/Operation
22.2 Operation
22.2.1 IDC registration sensor adjustment control
• Controls changes in characteristics due to change with time and contamination of the
transfer belt and IDC registration sensor, part-to-part variations in the sensors, and
change of environment.
• The intensity (current value) of the IDC registration sensor is adjusted on the surface of
the transfer belt, on which no toner sticks (background level).
22.2.2 Max. density adjustment control
• The developing bias (Vdc) is adjusted to control changes in the solid density resulting
from variations in developing characteristics and IDC registration sensor intensity, varia-
tions in sensitivity of the PC drum, and changes in the environment, durability, and the
amount of charge in toner.
• Patterns are produced on the surface of the transfer belt and the IDC registration sensor
detects the amount of toner sticking to them.
• Referring to the detected data and the environment data taken by the temperature/
humidity sensors, the developing bias value that results in the appropriate maximum
density is calculated and stored in memory.
• Thereafter, the grid voltage (Vg) value, including the background margin adjustment
value, is calculated and stored in memory.
22.2.3 LD (laser diode) intensity adjustment control
• It adjusts the variation in reproducibility of the thin line and the reverse outline, which is
resulting from the variations in electrostatic characteristics of the PC drum, developing
characteristics and transfer characteristics in terms of individual difference, environment
and durability, to make it the target level.
• It produces detection patterns on the surface of the transfer belt with the given level of LD
intensity and detects the output value of IDC sensor.
• LD intensity is calculated from the detected IDC sensor data.
22.2.4 Gamma correction control
• The intensity of LD in all gradation levels is adjusted to correct changes in gradation
characteristics to a linear one. The changes in gradation characteristics are caused by
variations in the PC drum sensitivity and developing characteristics and changes with
time and in environment.
• It produces gradation patterns on the transfer belt and calculates gradation characteris-
tics output by the current engine with the IDC registration sensor.
• The gamma correction data is calculated using the density measurements of different
gradation levels. The optimum LD intensity is set for each of the different gradation levels
Theory of Operation Y107522-3