Plasma-Density Imaging using a 2-Dimensional, Second-Harmonic, Dispersion Interferometer

Optical interferometers used for plasma-density measurements are often robustly mounted, two-arm, high-cost, high-maintenance installations. The Second- Harmonic Dispersion Interferometer (SHDI) is a greatly simplified approach, with a single, common-path optical axis. In this design the primary laser is frequency doubled before, and after, the plasma, in order to allow the dispersive-phase shift between the beams to be measured accurately. Overall the system design is low-cost and low-maintenance and provides superior performance compared to a standard microwave interferometer and second harmonic CO
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interferometer.[1]