Fabrication of polymer-based microstructures on optical multimode fibers

Optical microstructures, such as micro lenses or computer-generated holograms (CGH), have become increasingly important in recent years. Due to the miniaturization of optical sensors and components, tailored solutions for light forming are required. A high-precision and flexible approach to produce such adapted optical components is the two-photon polymerization (2 PP) lithography of UV-sensitive polymers. The 2PP lithography enables the fabrication of nearly arbitrary structures for optical elements, such as wave guides, diffractive optical elements (DOE) or micro lenses on different substrates. In this contribution we present the design and fabrication process as well as the characterization of different polymer based optical microstructures such as gratings, prisms, micro lenses fabricated on optical multimode fiber tips as examples for beam shaping and generation of arbitrary intensity distributions. The use of optical fibers as substrate material enables new applications for regions of interest that are hard to access otherwise, e.g. in medicine, optogenetics or sensor technology.