3D-printed facet-attached microlenses (FaML) could overcome photonic packaging challenges

https://phys.org/news/2023-07-3d-printed-facet-attached-microlenses-faml-photonic.html

"multi-photon lithography, shape emitted beams refractive or reflective surfaces. collimated to large diameter independent of device-specific mode fields relaxing axial and lateral alignment tolerances... passive machine vision or simple mechanical stops, inserting optical isolators or polarization beam splitters, into free-space beam paths between PIC facets... insertion losses 1.4 dB per interface, translational lateral 1 dB alignment tolerance ± 6 μm... flexible photonic packaging complement wafer-level mass fabrication underlying PIC"