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arXiv · 2309.04604

Microfabricated pinholes for high contrast imaging testbeds

Emory L. Jenkins·Kyle Van Gorkom·Kevin Derby·Patrick Ingraham·Ewan S. Douglas
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Abstract

In order to reach contrast ratios of $10^{-8}$ and beyond, coronagraph testbeds need source optics that reliably emulate nearly-point-like starlight, with microfabricated pinholes being a compelling solution. To verify, a physical optics model of the Space Coronagraph Optical Bench (SCoOB) source optics, including a finite-difference time-domain (FDTD) pinhole simulation, was created. The results of the FDTD simulation show waveguide-like behavior of pinholes. We designed and fabricated microfabricated pinholes for SCoOB made from an aluminum overcoated silicon nitride film overhanging a silicon wafer substrate, and report characterization of the completed pinholes.

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Emory L. Jenkins, Kyle Van Gorkom, Kevin Derby, Patrick Ingraham, Ewan S. Douglas. 2023-09-08. Microfabricated pinholes for high contrast imaging testbeds. https://arxiv.org/abs/2309.04604

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