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arXiv · 2203.12989

3D-printed facet-attached optical elements for beam shaping in optical phased arrays

Stefan Singer·Yilin Xu·Sebastian Tobias Skacel·Yiyang Bao·Heiner Zwickel·Pascal Maier·Lukas Freter·Philipp-Immanuel Dietrich·Mathias Kaschel·Christoph Menzel·Sebastian Randel·Wolfgang Freude·Christian Koos
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Abstract

We demonstrate an optical phased-array (OPA) equipped with a 3D-printed facet-attached element for shaping and deflection of the emitted beam. The beam shaper combines freeform refractive surfaces with total-internal-reflection (TIR) mirrors and is in-situ printed to edge-emitting waveguide facets using high-resolution multi-photon lithography, thereby ensuring precise alignment with respect to on-chip waveguide structures. In a proof-of-concept experiment, we achieve a grating-lobe free steering range of $\pm 30{\deg}$ and a full-width-halfmaximum (FWHM) beam divergence of approximately $2{\deg}$. The concept opens an attractive alternative to currently used grating structures and is applicable to a wide range of integration platforms.

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BibTeXRIS

Stefan Singer, Yilin Xu, Sebastian Tobias Skacel, Yiyang Bao, Heiner Zwickel, Pascal Maier, Lukas Freter, Philipp-Immanuel Dietrich, Mathias Kaschel, Christoph Menzel, Sebastian Randel, Wolfgang Freude, Christian Koos. 2022-03-24. 3D-printed facet-attached optical elements for beam shaping in optical phased arrays. https://doi.org/10.1364/oe.456952

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