A device for measuring an electric field in a conducting medium comprises: two electrodes separated by a volume of an insulating medium; a device for measuring current coupled to said electrodes; and adjustment elements making it possible to vary a quantity on which the electrical conductivity of the field measuring device depends.

A noncontact voltage measurement apparatus includes a sensing electrode to which a voltage corresponding to an alternating current voltage is applied, a feedback electrode, a conductive movable body that is supported so as to be displaceable in accordance with the Coulomb force generated between the movable body and the sensing electrode and the Coulomb force generated between the movable body and the feedback electrode, an elastic force for causing the movable body to return to a predetermined neutral position acting on the movable body, a displacement detection unit configured to detect a displacement of the movable body, a voltage applying unit configured to apply an alternating current voltage to the feedback electrode, and a control unit configured to control the voltage to be output from the voltage applying unit such that a detection result of the displacement from the displacement detection unit approaches a predetermined reference value.

A noncontact voltage measurement apparatus includes a sensing electrode to which a voltage corresponding to an alternating current voltage is applied, a feedback electrode, a conductive movable body that is supported so as to be displaceable in accordance with the Coulomb force generated between the movable body and the sensing electrode and the Coulomb force generated between the movable body and the feedback electrode, an elastic force for causing the movable body to return to a predetermined neutral position acting on the movable body, a displacement detection unit configured to detect a displacement of the movable body, a voltage applying unit configured to apply an alternating current voltage to the feedback electrode, and a control unit configured to control the voltage to be output from the voltage applying unit such that a detection result of the displacement from the displacement detection unit approaches a predetermined reference value.

Embodiments relate to a method, apparatus, and system for passively detecting strength of an electromagnetic field. An electroactive polymer (EAP) is configured with an antenna in communication with an RC circuit. The EAP is positioned proximal to a sensor. In response to receipt of a transient electromagnetic pulse due to an electrostatic discharge, the circuit captures the received pulse and transmits the pulse to the EAP. The EAP reacts to the pulse in the form of a deflection. The magnitude of the deflection correlates to the field strength which caused the received pulse. As deflection of the EAP is communicated to the proximally positioned sensor, a recording of the electrostatic discharge takes place.

A sensor device capable of measuring electric field strength of an external electric field includes a first dielectric layer, a first atomic layer material film disposed on the first dielectric layer and including one or more atomic layers formed of a first material, a channel layer disposed on the first atomic layer material film, including a channel region, and including one or more atomic layers of graphene, a second atomic layer material film disposed on the channel layer and including one or more atomic layers formed of a second material, and a first electrode and second electrode disposed on the channel layer across the channel region in a manner facing each other, wherein the second atomic layer material film includes a first side and a second side, the first side being disposed on the channel layer and the portion of the second side opposite from the channel region being exposed to the outside, or a second dielectric layer being disposed on the second side and the portion on the side opposite from the channel region of the side of the second dielectric layer opposite from the second atomic layer material film being exposed to the outside.

A sensor device capable of measuring electric field strength of an external electric field includes a first dielectric layer, a first atomic layer material film disposed on the first dielectric layer and including one or more atomic layers formed of a first material, a channel layer disposed on the first atomic layer material film, including a channel region, and including one or more atomic layers of graphene, a second atomic layer material film disposed on the channel layer and including one or more atomic layers formed of a second material, and a first electrode and second electrode disposed on the channel layer across the channel region in a manner facing each other, wherein the second atomic layer material film includes a first side and a second side, the first side being disposed on the channel layer and the portion of the second side opposite from the channel region being exposed to the outside, or a second dielectric layer being disposed on the second side and the portion on the side opposite from the channel region of the side of the second dielectric layer opposite from the second atomic layer material film being exposed to the outside.