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arXiv · 2003.13240

Demonstration of wideband metal mesh filters for submillimeter astrophysics using flexible printed circuits

Shinsuke Uno·Tatsuya Takekoshi·Tai Oshima·Keisuke Yoshioka·Kah Wuy Chin·Kotaro Kohno
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Abstract

We developed a wideband quasi-optical band-pass filter covering 170-520 GHz by exploiting the recent advancements in commercially available flexible printed circuit (FPC) fabrication technologies. We designed and fabricated a three-layered stack of loaded hexagonal grid metal meshes using a copper pattern with a narrowest linewidth of $50~\mu\mathrm{m}$ on a polyimide substrate. The measured frequency pass-band shape was successfully reproduced through a numerical simulation using a set of parameters consistent with the dimensions of the fabricated metal meshes. FPC-based metal mesh filters will provide a new pathway toward the on-demand development of millimeter/submillimeter-wave quasi-optical filters at low cost and with a short turnaround time.

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Shinsuke Uno, Tatsuya Takekoshi, Tai Oshima, Keisuke Yoshioka, Kah Wuy Chin, Kotaro Kohno. 2020-03-30. Demonstration of wideband metal mesh filters for submillimeter astrophysics using flexible printed circuits. https://doi.org/10.1364/ao.389605

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