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Updated: Jul 17, 2025
12:14
The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
21.8K
Characterization of a retroreflector array for 320-GHz interferometer system in Heliotron J
1Graduate School of Energy Science, Kyoto University, Uji, Kyoto 611-0011, Japan.
The Review of Scientific Instruments
|September 6, 2023
Summary
A retroreflector array shows diffraction effects in fusion plasma experiments, creating beam peaks. However, most power reflects directly, and a lens can suppress intensity variations for interferometer applications.
Area of Science:
- Optics and Photonics
- Plasma Physics
- Interferometry
Background:
- Retroreflector arrays offer unique optical properties for spatially constrained environments.
- Michelson-type interferometers are crucial for plasma diagnostics.
Purpose of the Study:
- To experimentally investigate the optical properties of a retroreflector array.
- To assess its suitability for Michelson interferometry in fusion plasma experiments.
Main Methods:
- A tabletop experiment using a 320-GHz submillimeter wave source and a retroreflector array.
- An imaging camera measured submillimeter wave beam profiles.
- Characterization of reflected beam properties and angular dependence.
Main Results:
- Observed diffraction effects leading to discrete peaks in the reflected beam profile.
- Confirmed that the majority of reflected power converges in the incident direction.
- Identified intensity variations due to diffraction, dependent on incident beam angle.
Conclusions:
- Retroreflector arrays exhibit predictable diffraction patterns and strong retroreflection.
- A focusing lens can mitigate intensity fluctuations for practical interferometer use.
- The study validates retroreflector arrays as viable tools for limited-space plasma diagnostics.
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