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arXiv · 2607.14841

Millimetre-scale spectrographs for next-generation photonic instrumentation

Emily Ronson·Robert J. Harris·Ariadna Calcines Rosario·Viktoria Kutnohorsky
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Abstract

We present a set of ultra-compact spectrographs fabricated using two-photon polymerisation, each under 1 mm in length and printed directly onto an optical fiber. This fully integrated, alignment-free architecture enables extremely low-mass instrumentation with broad potential across astrophotonics, space systems, drone-based sensing, and quantum optics. Two transmissive configurations are presented; they combine beam-expansion optics, dispersive elements, and stray-light suppression within monolithic printed structures optimised for J- and H-band operation. Coarse gratings provide resolving powers of approximately R = 30. Experimental characterisation confirms the feasibility of fiber-coupled, fully printed spectrographs and demonstrates their promise as deployable components for next-generation integrated photonic instrumentation.

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Emily Ronson, Robert J. Harris, Ariadna Calcines Rosario, Viktoria Kutnohorsky. 2026-07-16. Millimetre-scale spectrographs for next-generation photonic instrumentation. https://arxiv.org/abs/2607.14841

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