A compact, large-aperture tunable lens with adaptive spherical correction

In this paper, we present the proof of concept of a very fast adaptive glass membrane lens with a large aperture/diameter ratio, spherical aberration correction and integrated actuation. The membrane is directly deformed using two piezo actuators that can tune the focal length and the conical parameter. This operating principle allows for a usable aperture of the whole membrane diameter. Together with the efficient actuation mechanism, the aperture is around 2/3 of the total system diameter - at a thickness of less than 2mm. The response time is a few milliseconds at 12mm aperture, which is fast compared to similar systems.Comment: Presented at the IEEE 2014 International Symposium on Optomechatronic Technologies (ISOT 2014), 4 pages PD

Bio-inspired variable imaging system simplified to the essentials: Modelling accommodation and gaze movement

A combination of an aspherical hybrid diffractive-refractive lens with a flexible fluidic membrane lens allows the implementation of a light sensitive and wide-aperture optical system with variable focus. This approach is comparable to the vertebrate eye in air, in which the cornea offers a strong optical power and the flexible crystalline lens is used for accommodation. Also following the natural model of the human eye, the decay of image quality with increasing field position is compensated, in the optical system presented here, by successively addressing different tilting angles which mimics saccadic eye-movements. The optical design and the instrumental implementation are presented and discussed, and the working principle is demonstrated

Volumetric HiLo microscopy employing an electrically tunable lens

Electrically tunable lenses exhibit strong potential for fast motion-free axial scanning in a variety of microscopes. However, they also lead to a degradation of the achievable resolution because of aberrations and misalignment between illumination and detection optics that are induced by the scan itself. Additionally, the typically nonlinear relation between actuation voltage and axial displacement leads to over- or under-sampled frame acquisition in most microscopic techniques because of their static depth-of-field. To overcome these limitations, we present an Adaptive-Lens-High-and-Low-frequency (AL-HiLo) microscope that enables volumetric measurements employing an electrically tunable lens. By using speckle-patterned illumination, we ensure stability against aberrations of the electrically tunable lens. Its depth-of-field can be adjusted a-posteriori and hence enables to create flexible scans, which compensates for irregular axial measurement positions. The adaptive HiLo microscope provides an axial scanning range of 1 mm with an axial resolution of about 4 μm and sub-micron lateral resolution over the full scanning range. Proof of concept measurements at home-built specimens as well as zebrafish embryos with reporter gene-driven fluorescence in the thyroid gland are shown

Cyber-Physical Pump and Valve Agents Master Uncertain Information and Demand at Pareto-Optimal Energy Costs and Control Accuracy

This dataset contains the raw data as well as plotted data of the study "Comparing Approaches to Distributed Control of Fluid Systems based on Multi-Agent Systems". The study was carried out within the scope of the project "Multiagentensysteme zur verteilten Regelung von Fluidsystemen" funded by "VDMA Pumpen und Systeme" between January 1st, 2021 and December 31st, 2021. The work in the project was carried out by Tim Müller with the support of Kevin Logan. The Chairman of the project was Jochen Schaab of KSB and the contact person of VDMA was Harald Frank. The study was conducted by Kevin Logan and Marius Stürmer in equal parts as well as Tim Müller under the supervision of Prof. Peter F. Pelz.Updated figure files to include correct figure numbers after updating manuscrip