Potential measuring device and image forming apparatus using the same
AssigneeCanon Kabushiki Kaisha
InventorsYoshikatsu Ichimura, Takashi Ushijima, Atsushi Kandori, Yoshitaka Zaitsu
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Abstract
A potential measuring device for measuring a potential of a measurement object, includes a detection electrode that faces the measurement object, a reference electrode disposed in a vicinity of the detection electrode that is electrostatically shielded by an electrostatic shield structure with respect to the measurement object, and capacitance modulator for modulating an electrostatic coupled capacitance between the detection electrode and the measurement object to measure a potential of the measurement object by using an electric signal generated on the detection electrode and an electric signal generated on the reference electrode.
Claims13
A potential measuring device for measuring a potential of a measurement object, said device comprising:
- a detection electrode;
- a reference electrode that is electrostatically shielded constantly during potential measurement by an electrostatic shield structure with respect to the measurement object;
- a capacitance modulator for modulating an electrostatic coupled capacitance between said detection electrode and the measurement object;
- and
- a measuring circuit for measuring a potential of the measurement object by using an electrical signal generated on said detection electrode and an electrical signal generated on said reference electrode.
A method of measuring a potential of a measurement object, said method comprising:
- preparing a potential measuring device comprising a detection electrode disposed to face the measurement object, and a reference electrode that is disposed in a vicinity of the detection electrode and that is electrostatically shielded constantly during potential measurement by an electrostatic shield structure with respect to the measurement object;
- modulating an electrostatic coupled capacitance between said detection electrode and the measurement object;
- detecting a first electrical signal generated on said detection electrode;
- detecting a second electrical signal generated on said reference electrode;
- and
- measuring the potential of the measurement object based on the first electrical signal and the second electrical signal.
Dependencies are inferred from the claim text.