Optical fiber sensor for electric field and electric charge using low-coherence, Fabry-Perot interferometry

Area of Science:

• Physics
• Materials Science
• Electrical Engineering

Background:

• Electric field measurement is crucial in various scientific and industrial applications.
• Existing methods for electric field sensing can be complex or limited in scope.
• The need for sensitive, non-contact electric field and charge sensors persists.

Purpose of the Study:

• To develop and demonstrate a novel optical fiber sensor for measuring electric fields and electric charge.
• To utilize cantilever deflection and interferometry for precise sensing.
• To validate the sensor's performance against theoretical models.

Main Methods:

• Development of an optical fiber sensor head incorporating a small cantilever.
• Employing low-coherence Fabry-Perot interferometry to measure cantilever deflection.
• Calibrating and testing the sensor in the electric field generated by a Van de Graaff generator.
• Comparing experimental results with a theoretical model based on electrostatic and mechanical forces.

Main Results:

• The developed optical fiber sensor successfully measured electric fields in the range of 135-650 V/cm.
• Measured cantilever deflections showed good agreement with predictions from the electrostatic-mechanical force balance model.
• The sensor demonstrated sensitivity to electric fields and induced charging.

Conclusions:

• The optical fiber cantilever sensor is a viable technology for electric field and charge measurement.
• Fabry-Perot interferometry provides a robust method for detecting small deflections in this sensing application.
• The sensor's performance validates the underlying physical principles and its potential for practical use.