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arXiv · 1407.5892

Large-area Reflective Infrared Filters for Millimeter/sub-mm Telescopes

Z. Ahmed·J. A. Grayson·K. L. Thompson·C. L. Kuo·G. Brooks·T. Pothoven
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Abstract

Ground-based millimeter and sub-millimeter telescopes are attempting to image the sky with ever-larger cryogenically-cooled bolometer arrays, but face challenges in mitigating the infrared loading accompanying large apertures. Absorptive infrared filters supported by mechanical coolers scale insufficiently with aperture size. Reflective metal-mesh filters placed behind the telescope window provide a scalable solution in principle, but have been limited by photolithography constraints to diameters under 300 mm. We present laser etching as an alternate technique to photolithography for fabrication of large-area reflective filters, and show results from lab tests of 500 mm-diameter filters. Filters with up to 700 mm diameter can be fabricated using laser etching with existing capability.

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Z. Ahmed, J. A. Grayson, K. L. Thompson, C. L. Kuo, G. Brooks, T. Pothoven. 2014-07-22. Large-area Reflective Infrared Filters for Millimeter/sub-mm Telescopes. https://doi.org/10.1007/s10909-014-1141-5

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