Parallel two-photon photopolymerization of microgear patterns

Parallel direct laser writing of micro-optical and photonic structures using spatial light modulator

“…This technology is only suitable for the fabrication of structures with a constant period. Other attempts involve holographic lithography [13,14] and the use of shaped beams [15]. However, with these methods, only microstructures with specific profiles can be fabricated.…”

44‐3: Large Area Multi‐Layer Liquid Crystal Phase Modulators Enabled by Two‐Photon Polymerization

“…In order to improve the time bottleneck of direct laser writing, researchers have developed a number of approaches. These use holographic components [26], micro-lens arrays or spatial light modulators [27,28] to create multi-focal-point beams which produce structures in parallel. Implementing one of these methods for the fabrication of the multilayer LC phase modulator could drastically increase the throughput of such devices.…”

GPC-enhanced read-out of holograms

“…However, the inherent presence of speckles is one major drawback of this beam shaping technique. A major cause of speckles in diffractively-generated extended light patterns is the "randomly" oscillating phase distribution at the far-field reconstruction plane mainly caused by cross-talk between adjacent output resolution elements due to the optical convolution process with the point spread function (PSF) of the system [19,20]. Considering that we get 4:3 rectangular output with both GPC LS and hard truncation, the PSF for both will have a 2D sinc profile matching the 4:3 aspect ratio and the difference will only be by a scaling factor due to the gain in the GPC LS.…”