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Humidity Sensitivity and Coil Design of a High-Precision Eddy-Current Displacement Sensor^{ †}

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## Abstract

**:**

## 1. Introduction

## 2. Sensitivity to Parasitic Capacitance Change

## 3. Sensitivity to Humidity Variation

## 4. Conclusions

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**(

**a**) Front view and cross-section of an ECDS probe with a flat sensing coil. The coil not only has an inductance that varies with standoff ${x}_{\mathrm{so}}$, but also has a parasitic interwinding capacitance; (

**b**) Schematic of the sensor’s front-end [4].

**Figure 2.**(

**a**) The coil geometry used in this study. (

**b**) Magnetic (left) and electric (right) field lines of the mode corresponding to the SRF of the coil.

**Figure 3.**(

**a**) Capacitance variation that leads to a 0.1 nm measurement error as a function of the normalized SRF (solid line) and the capacitance deviation resulting from a humidity variation of 1% and 10% (dashed lines); (

**b**) Humidity variation as function of the normalized SRF.

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## Share and Cite

**MDPI and ACS Style**

Vogel, J.G.; Chaturvedi, V.; Nihtianov, S.
Humidity Sensitivity and Coil Design of a High-Precision Eddy-Current Displacement Sensor. *Proceedings* **2017**, *1*, 283.
https://doi.org/10.3390/proceedings1040283

**AMA Style**

Vogel JG, Chaturvedi V, Nihtianov S.
Humidity Sensitivity and Coil Design of a High-Precision Eddy-Current Displacement Sensor. *Proceedings*. 2017; 1(4):283.
https://doi.org/10.3390/proceedings1040283

**Chicago/Turabian Style**

Vogel, Johan G., Vikram Chaturvedi, and Stoyan Nihtianov.
2017. "Humidity Sensitivity and Coil Design of a High-Precision Eddy-Current Displacement Sensor" *Proceedings* 1, no. 4: 283.
https://doi.org/10.3390/proceedings1040283