A Millimeter-Wave Photometric Camera for Long-Range Imaging Through Optical Obscurants Using Kinetic Inductance Detectors

Jack Sayers; Daniel Cunnane; Sage Crystian; Peter K. Day; Fabien Defrance; Byeong Ho Eom; Jonathan Greenfield; Matthew Hollister; Bradley R. Johnson; Henry G. LeDuc; Philip Mauskopf; Nia McNichols; Cody Roberson; Marcus C. Runyan; Adhitya B. Sriram; Sage Stanton; Ryan C. Stephenson; Liam C. Walters; Eric Weeks

arXiv · 2502.14607

A Millimeter-Wave Photometric Camera for Long-Range Imaging Through Optical Obscurants Using Kinetic Inductance Detectors

Jack Sayers·Daniel Cunnane·Sage Crystian·Peter K. Day·Fabien Defrance·Byeong Ho Eom·Jonathan Greenfield·Matthew Hollister·Bradley R. Johnson·Henry G. LeDuc·Philip Mauskopf·Nia McNichols·Cody Roberson·Marcus C. Runyan·Adhitya B. Sriram·Sage Stanton·Ryan C. Stephenson·Liam C. Walters·Eric Weeks

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Abstract

Passive imaging through optical obscurants is a promising application for mm-wave sensing. We have thus developed the Superconducting Kinetic Inductance Passive Radiometer (SKIPR), a 150 GHz polarization-sensitive photometric camera optimized for terrestrial imaging using a focal plane array with 3,840 kinetic inductance detectors (KIDs). We present a full description of the instrument design, with a particular emphasis on the cryogenic system based on a Gifford-McMahon cryocooler with a two-stage Adiabatic Demagnetization Refrigerator and a dedicated 1.59 m crossed Dragone telescope with an altitude/azimuth mount. We include a detailed lab-based characterization of the KIDs, which results in a determination of their superconducting resonator parameters and optical properties. We also present in situ measurements from the telescope, including point-spread functions and noise characterization. In sum, we find that SKIPR performs as expected, providing diffraction-limited imaging with detector noise performance set by the random arrivals of photons from the ambient background. There is minimal variation in detector characteristics over the full SKIPR focal plane array, and the overall detector yield is 92 per cent.

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Jack Sayers, Daniel Cunnane, Sage Crystian, Peter K. Day, Fabien Defrance, Byeong Ho Eom, Jonathan Greenfield, Matthew Hollister, Bradley R. Johnson, Henry G. LeDuc, Philip Mauskopf, Nia McNichols, Cody Roberson, Marcus C. Runyan, Adhitya B. Sriram, Sage Stanton, Ryan C. Stephenson, Liam C. Walters, Eric Weeks. 2025-02-20. A Millimeter-Wave Photometric Camera for Long-Range Imaging Through Optical Obscurants Using Kinetic Inductance Detectors. https://arxiv.org/abs/2502.14607

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