Geoscience Reference
In-Depth Information
5. Summary
The rotation of the polarization plane of a beam propagating through
a region of high-voltage discharge was estimated. To extend the optical
path length in the vicinity of the discharge, repeating mirror optics was
devised. The experimental setup was installed in a discharge chamber. As
a result, the rotation angle was estimated as < 1 deg. To detect such a small
angle, the sensitivity of the system needed to have a dynamic range of
30 dB. The rotation of the polarization plane was experimentally measured
to be 0.29 deg, which was in agreement with the simulation results.
Electromagnetic measurement using the Faraday effect can be applied
to lidar measurement of lightning discharges. As the pulse beam enables
time-resolved detection, evaluation of the lightning strike position, measure-
ment of the change in the electromagnetic field, and spatial distribution of
ionization should be possible.
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