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arXiv · 1808.04692

FPGA based demodulation of laser induced fluorescence in plasmas

Sean Mattingly·Fred Skiff
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Abstract

We present a field programmable gate array (FPGA)-based system that counts photons from laser-induced fluorescence (LIF) on a laboratory plasma. This is accomplished with FPGA-based up/down counters that demodulate the data, giving a background-subtracted LIF signal stream that is updated with a new point as each laser amplitude modulation cycle completes. We demonstrate using the FPGA to modulate a laser at 1 MHz and demodulate the resulting LIF data stream. This data stream is used to calculate an LIF-based measurement sampled at 1 MHz of a plasma ion fluctuation spectrum.

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Sean Mattingly, Fred Skiff. 2018-08-13. FPGA based demodulation of laser induced fluorescence in plasmas. https://doi.org/10.1063/1.4995971

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