Image Density Control; Manualimag Edensitycontrol - Ricoh FT4430 Service Manual

IMAGE DENSITY CONTROL

Image density is controlled by changing two items: (1) the strength of the
voltage applied to the development roller sleeve, and (2) the strength of the
voltage applied to the exposure lamp.
Applying a bias voltage to the development sleeve reduces the potential
between the development roller and the drum, thereby reducing the amount
of toner transferred. As the bias voltage becomes greater, the copy image
becomes lighter. Similarly, increasing the voltage to the exposure lamp
causes an increase in light intensity which also results in lighter copies.
The method of control is different depending on whether
manually selected or the automatic ID system is used. "
1. Manual Image Density Control
Manual Image Density Control
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When the image density is set manually, the bias depends on two factors: the
auto image density base level, and the manually selected ID level. (See the
above table. ) The exposure lamp voltage also varies as shown in the table.
NOTE: To set the auto image density base level, simultaneously press and
hold the Clear/Stop key and press the Auto ID key. Then, select the
base level using the manual ID keys.
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16 April '88
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