Conference Agenda

Freeform optics is a rising field in modern optics. Direct 3D printing is promising method for manufacturing freeform surfaces, but many of the 3D printing methods lack the desired surface roughness values for optics. This study is focused to prove that inkjet-based 3D printing is valid manufacturing method for freeform optics. In this study two different freeform components, flattop lens and lens that creates UEF logo, are designed and manufactured using inkjet printing. Flattop lens creates uniform square illumination and logo lens creates recognizable logo. Based on these findings’ inkjet printing is viable at least for illumination optics.

This work decomposes the wavefront at the exit pupil of an optical system into two parts: the viewpoint–invariant and the viewpoint–dependent parts. The decomposition is achieved by calculating the first and second derivatives of the wavefront and by constructing viewpoint–invariant curvature maps and viewpoint–dependent descriptors. Analysis of the former yields intrinsic properties of the wavefront, such as the radius of the base sphere, the asphericity, etc., while the latter include, among other things, an astigmatism map, the vertex and the tilt. These maps/descriptors provide intuitive information suitable for evaluation and compensation of aberrations in the optical system.

To manufacture electro-optical printed circuit boards (EOPCBs) cost-effectively, the conventional PCB manufacturing process must not be affected by the integration of optical waveguides. In this work, flexo-printing, is combined with slot-die coating for this application. This improves waveguide integration in cladding, with advantages for PCB integration. It reduces interface roughness between core and cladding, and consequently results in lower attenuation.

Fluorescence lifetime imaging microscopy (FLIM) is investigated as a contrast mechanism for the characterization of heterogeneous luminescent materials. A Ce:YAG glass-ceramic sample is used as a model system under epi-fluorescence excitation with a 450~nm narrowband pulsed laser. While the recorded intensity image reveals structural features within the sample, it does not allow an unambiguous separation of the underlying emitting contributions. In contrast, analysis of the fluorescence decay behavior reveals distinct lifetime components and spatially varying decay characteristics. Lifetime-weighted representations therefore provide a clearer differentiation of overlapping luminescent regions than intensity imaging alone. The results demonstrate the potential of FLIM for material studies based on luminescence contrast.

Blazed gratings in silicon with very low blaze angle (below 1°), smooth blaze facets and low wave front error are essential as high-performance monochromator gratings in synchrotron applications like free electron lasers (FEL). In this contribution, we demonstrate a new scalable reactive ion beam etching approach to produce blazed gratings in silicon with low blaze angle and smooth blaze facets. In the first step, a laminar resist pattern is etched under oblique ion incidence to fabricate a blazed grating in a thermal SiO2 layer on the silicon substrate. Afterwards, this blazed grating is transferred into the silicon and simultaneously compressed to a lower blaze angle. The method was tested for 600 l/mm and 2000 l/mm gratings and yielding blaze angles of 0.34° and 0.29°, respectively, as well as a roughness Sq of less than 0.2 nm.

A parametric study for laser ablation cleaving SMF-28 optical fibers is presented.

This study investigates the angle of incidence and the laser focus position relative

to the fiber as two key process parameters influencing the resulting fiber cleave

angle.

Replicated micro-optics has readily been established in commercial applications, mostly for single aperture optical systems. Their arrayed counterparts, featuring potentially large arrays of apertures, is still restricted to optical systems relying on a single or few elements only. But advanced replication techniques enable for preparing e.g. achromatic refractive elements, which in turn pave the way to complex optical functions. Despite technological limits confining the achievable application range, interesting applications have been addressed, thus yielding functional devices within construction spaces not achievable by classical systems. Starting from established approaches, the talk introduces both the replications technology as well as developments for microscopic and spectroscopic applications.