Exposure and development control apparatus for electrostatic copying machine
AssigneeRicoh Company, Ltd.
InventorsKoichi Suzuki, Shigeru Suzuki
Life of this patent
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Abstract
An optical system focusses a light image of a linear portion of an original document onto a rotating photoconductive drum. The optical system scans the document so as to progressively form an electrostatic image on the drum. A scanning linear photosensor array is disposed such that the light image is incident thereon. Maximum and minimum output levels of the array are sensed, and the illumination intensity of the document and a developing bias voltage are controlled as functions thereof.
Claims10
In an electrostatic copying machine having optical means for scanning an original document and focussing a light image of a substantially linear portion of the document onto a moving photoconductive member to progressively form an electrostatic image of the entire document on the photoconductive member, an apparatus comprising;
- a scanning linear photosensor array having a plurality of photoelectric sensor elements which are enabled in sequence to produce respective output signals having levels corresponding to incident light intensity, the photosensor array being disposed such that the light image is incident thereon;
- first sensor means for detecting a maximum output level of the photosensor array;
- second sensor means for detecting a minimum output level of the photosensor array;
- and
- at least one variable operating parameter of the copying machine being controlled in accordance with the detected maximum and minimum output levels.
Dependencies are inferred from the claim text.