Stitching-free 3D printing of millimeter-sized highly transparent spherical and aspherical optical components

We demonstrate the fabrication of optical elements on the millimeter scale by stitching-free 3D printing via two-photon polymerization, using a commercial microfabrication system (Nanoscribe GmbH). Previous limitations are overcome by the use of a large writing field objective as well as a novel high transparency resist. The printed optical components are free of stitching defects due to a single step exposure and exhibit an unpreceded glass-like appearance due to the low absorption of the resist material throughout the entire visible wavelength range. We print aspherical focusing lenses, characterize and optimize their shape fidelity, and find their optical performance close to the simulated optimum. For comparison with commercially available glass lenses we also fabricate spherical half-ball lenses of different sizes. The imaging quality of the lenses is very similar, underpinning the powerfulness of our fabrication strategy.