Abstract: To provide an electric potential measuring device which is useful in realizing size reduction, high sensitivity, and high reliability. The electric potential measuring device includes: an oscillating device which includes torsion springs, and an oscillating body axially supported by the springs to oscillate; and signal detecting unit which is located on a surface of the oscillating body. A capacitance between the detection electrode and a surface of an electric potential measuring object is varied by varying a distance therebetween by the oscillating device, whereby an output signal appearing on the detection electrode is detected.

Abstract: Disclosed in a non-contacting electric potential sensor capable of being readily reduced in its size, which includes a detecting electrode, an electrically-conductive movable shutter, and a driving unit for driving the electrically-conductive movable shutter. The detecting electrode is to be placed facing a measurement object whose electric potential is to be measured. The electrically-conductive movable shutter is disposed so as to be movably located in a spacing formed between the detecting electrode and the measurement object when the detecting electrode is placed facing the measurement object, so that an exposure degree of the detecting electrode against the measurement object can be controlled. The driving unit includes a current injecting unit for selectively injecting current into the electrically-conductive movable shutter in a direction approximately perpendicular to a moving direction of the electrically-conductive movable shutter.

Abstract: An electric potential measuring apparatus includes a detecting electrode, a modulator for changing an electrostatic capacitance between a measurement object and the detecting electrode by mechanical vibration, a charge detector for detecting the amount of charges electrostatically induced in the detecting electrode by the modulator, and a vibration generating-detecting unit for selectively performing either a vibration generating function of exciting the mechanical vibration, or a detecting function of detecting the condition of the mechanical vibration.

Abstract: An electric potential sensor includes a detecting electrode, a capacitor modulating unit for modulating a coupling capacitance between the detecting electrode and a measurement object by using an electrostatic force, and a shielding unit for electrically shielding the detecting electrode from electric fields due to the electrostatic force of the capacitor modulating unit. An electric potential of the measurement object is measured based on a change caused by the capacitor modulating unit in the amount of electrical charge induced in the detecting electrode. Entrance of lines of electric force due to the electrostatic force of the capacity modulating unit into the detecting electrode is prevented or reduced, so that an unfavorable mixture of driving noise into an output signal of the detecting electrode can be prevented or reduced.

Abstract: Provided is a potential measuring device for measuring a potential of a measurement object, comprising a detection electrode disposed to face the measurement object, a reference electrode disposed in a vicinity of the detection electrode, an electrostatic shield structure for electrostatically shielding the reference electrode 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.

Abstract: A potential measuring apparatus has a detection electrode on which an electric charge is induced according to a potential of a detection object, and a modulator for altering the generated quantity of the electric charge. The detection electrode has at least one depressed portion on a surface opposite to the detection object.

Abstract: A potential sensor (101) including first and second detection electrodes (121 a, b) opposed to an object of which a potential is to be measured, and a movable shutter (125) so positioned between the detection electrodes and the potential-measured object with gaps thereto; wherein the movable shutter can assume a first state and a second state, the first detection electrode is exposed to the potential-measured object wider when the movable shutter assumes the first state than when the movable shutter assumes the second state, and the second detection electrode is exposed to the potential-measured object narrower when the movable shutter assumes the first state than when the movable shutter assumes the second state.

Abstract: An electric potential measuring device comprises a detection electrode of a conductive material disposed in opposition to an object and a movable structure comprised of a first solid material portion of another dielectric and a second solid material portion of another dielectric or a conductive material. A charge induced on the detection electrode by electric lines of force from the object is modulated by moving the movable structure with a drive mechanism, to measure an electric potential of the object. An image forming apparatus comprises the electric potential measuring device and an image forming means for performing a control of an image formation by using the electric potential measuring device.

Abstract: To provide an electric potential measuring device which is useful in realizing size reduction, high sensitivity, and high reliability. The electric potential measuring device includes: an oscillating device which includes torsion springs, and an oscillating body axially supported by the springs to oscillate; and signal detecting unit which is located on a surface of the oscillating body. A capacitance between the detection electrode and a surface of an electric potential measuring object is varied by varying a distance therebetween by the oscillating device, whereby an output signal appearing on the detection electrode is detected.

Abstract: An electric potential measuring apparatus including a substrate disposed facing a measurement object, a detecting electrode provided insulated from the substrate, and a capacity modulating unit for modulating a coupling capacity between the detecting electrode and the measurement object. In the electric potential measuring apparatus, a region with a dielectric constant less than a dielectric constant of the substrate is formed in the substrate to achieve an increase in resistivity of a portion of the substrate between detecting electrodes, or a decrease in a stray capacity between the detecting electrode and the substrate.

Abstract: An electric potential measuring apparatus including a substrate disposed facing a measurement object, a detecting electrode provided insulated from the substrate, and a capacity modulating unit for modulating a coupling capacity between the detecting electrode and the measurement object. In the electric potential measuring apparatus, a region with a dielectric constant less than a dielectric constant of the substrate is formed in the substrate to achieve an increase in resistivity of a portion of the substrate between detecting electrodes, or a decrease in a stray capacity between the detecting electrode and the substrate.

Abstract: An electric potential measuring apparatus including a substrate disposed facing a measurement object, a detecting electrode provided insulated from the substrate, and a capacity modulating unit for modulating a coupling capacity between the detecting electrode and the measurement object. In the electric potential measuring apparatus, a region with a dielectric constant less than a dielectric constant of the substrate is formed in the substrate to achieve an increase in resistivity of a portion of the substrate between detecting electrodes, or a decrease in a stray capacity between the detecting electrode and the substrate.

Abstract: An electric potential sensor includes a detecting electrode, a capacitor modulating unit for modulating a coupling capacitance between the detecting electrode and a measurement object by using an electrostatic force, and a shielding unit for electrically shielding the detecting electrode from electric fields due to the electrostatic force of the capacitor modulating unit. An electric potential of the measurement object is measured based on a change caused by the capacitor modulating unit in the amount of electrical charge induced in the detecting electrode. Entrance of lines of electric force due to the electrostatic force of the capacity modulating unit into the detecting electrode is prevented or reduced, so that an unfavorable mixture of driving noise into an output signal of the detecting electrode can be prevented or reduced.

Abstract: Disclosed in a non-contacting electric potential sensor capable of being readily reduced in its size, which includes a detecting electrode, an electrically-conductive movable shutter, and a driving unit for driving the electrically-conductive movable shutter. The detecting electrode is to be placed facing a measurement object whose electric potential is to be measured. The electrically-conductive movable shutter is disposed so as to be movably located in a spacing formed between the detecting electrode and the measurement object when the detecting electrode is placed facing the measurement object, so that an exposure degree of the detecting electrode against the measurement object can be controlled. The driving unit includes a current injecting unit for selectively injecting current into the electrically-conductive movable shutter in a direction approximately perpendicular to a moving direction of the electrically-conductive movable shutter.

Abstract: Disclosed in a non-contacting electric potential sensor capable of being readily reduced in its size, which includes a detecting electrode, an electrically-conductive movable shutter, and a driving unit for driving the electrically-conductive movable shutter. The detecting electrode is to be placed facing a measurement object whose electric potential is to be measured. The electrically-conductive movable shutter is disposed so as to be movably located in a spacing formed between the detecting electrode and the measurement object when the detecting electrode is placed facing the measurement object, so that an exposure degree of the detecting electrode against the measurement object can be controlled. The driving unit includes a current injecting unit for selectively injecting current into the electrically-conductive movable shutter in a direction approximately perpendicular to a moving direction of the electrically-conductive movable shutter.

Abstract: Disclosed in a non-contacting electric potential sensor capable of being readily reduced in its size, which includes a detecting electrode, an electrically-conductive movable shutter, and a driving unit for driving the electrically-conductive movable shutter. The detecting electrode is to be placed facing a measurement object whose electric potential is to be measured. The electrically-conductive movable shutter is disposed so as to be movably located in a spacing formed between the detecting electrode and the measurement object when the detecting electrode is placed facing the measurement object, so that an exposure degree of the detecting electrode against the measurement object can be controlled. The driving unit includes a current injecting unit for selectively injecting current into the electrically-conductive movable shutter in a direction approximately perpendicular to a moving direction of the electrically-conductive movable shutter.