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arXiv · 2106.01778

Direct (3+1)D laser writing of graded-index optical elements

Xavier Porte·Niyazi Ulas Dinc·Johnny Moughames·Giulia Panusa·Caroline Juliano·Muamer Kadic·Christophe Moser·Daniel Brunner·Demetri Psaltis
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Abstract

We propose single-step additive fabrication of graded-index optical elements by introducing the light exposure as the additional dimension to three-dimensional (3D) laser writing, hence (3+1)D writing. We use a commercial printer and photoresist to realize the proposed single step fabrication method that can be swiftly adopted for research and engineering. After presenting the characterization of the graded-index profiles via basic structures, we demonstrate two different optical devices: volume holograms that are superimposed using angular and peristrophic multiplexing, and optical waveguides with well-defined refractive index profiles. In the latter, we precisely control the propagating modes via tuning the (3+1)D-printed waveguide parameters and report step-index and graded-index core-cladding transitions.

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Xavier Porte, Niyazi Ulas Dinc, Johnny Moughames, Giulia Panusa, Caroline Juliano, Muamer Kadic, Christophe Moser, Daniel Brunner, Demetri Psaltis. 2021-06-03. Direct (3+1)D laser writing of graded-index optical elements. https://doi.org/10.1364/optica.433475

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