Electric Field Sensor

The electric field sensor stabilizes measurements by applying a reference signal to correct for temperature and noise-induced fluctuations, ensuring accurate electric field detection using electro-optic effects.

JP7619553B2Active Publication Date: 2025-01-22YOKOGAWA ELECTRIC CORP +1
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Patent Information

Application Number
JP2018180875
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2018-09-26
Publication Date
2025-01-22
Estimated Expiration
2038-09-26

AI Technical Summary

Technical Problem

Conventional electric field sensors using the electro-optic effect suffer from measurement instability due to temperature dependence, thermal expansion, and fluctuations in sensitivity caused by changes in ambient temperature and stress, which affect the first-order electro-optic constant and natural birefringence of optical crystals, leading to inaccurate electric field measurements.

Method used

The electric field sensor incorporates a reference electric field means to apply a known reference signal to the electro-optic crystal, utilizing separation correction means with lock-in amplifiers and gain control to monitor and correct signal levels, thereby isolating the measurement signal from temperature and noise fluctuations, ensuring stable electric field measurements.

Benefits of technology

This configuration allows for accurate and stable electric field measurements by correcting for fluctuations in the first-order electro-optic constant and temperature changes, enhancing measurement stability and sensitivity.

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Patent Text Reader

Abstract

To provide an electric field sensor capable of measuring electric field strength without losing measurement stability because of a change in an ambient temperature or the like in the electric field sensor utilizing an electro-optic effect.SOLUTION: An electric field sensor is the electric field sensor for measuring an electric field emitted by an object utilizing an electro-optic effect. The electric field sensor includes: a light source; an electro-optic crystal on which light in a predetermined polarization state based on light emitted from the light source impinges to receive an electric field emitted by the object; reference electric field means for applying, to the electro-optic crystal, an electric field based on a reference signal having a known signal level; light reception means for receiving light emitted from the electro-optic crystal to convert the received light to an electric signal; and separation correction means for separating a measurement signal based on an electric field emitted by the object from an electric signal from a reference signal and correcting a signal level of a measurement signal on the basis of a signal level of the separated reference signal.SELECTED DRAWING: Figure 1
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Citation Information

Patent Citations

  • Optical DC transformer

    JP1990143173A

  • Surface potential measuring apparatus

    JP1995181211A

  • Electric field sensor head and electric field sensor apparatus using the same

    JP1999006849A

  • Optical electric field sensor

    JP2002122622A

  • Optical electric voltage / electric field sensor corresponding to direct current and isolated amplifier

    JP2007101384A