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Time-of-flight (TOF) magnetic sensing of rolling immunomagnetically-labeled cells offers great potential for single cell function analysis at the bedside in even optically opaque media, such as whole blood. However, due to the spatial resolution of the sensor and the low flow rate regime required to observe the behavior of rolling cells, the concentration range of such a workflow is limited. Potential clinical applications, such as testing of leukocyte function, require a cytometer which can cover a cell concentration range of several orders of magnitude. This is a challenging task for an integrated dilution-free workflow, as for high cell concentrations coincidences need to be avoided, while for low cell concentrations sufficient statistics should be provided in a reasonable time-to-result. Here, we extend the spatial bandwidth of a magnetoresistive sensor with an adaptive and integratable workflow concept combining mechanical and magnetophoretic guiding of magnetically labeled targets for in-situ enrichment over a dynamic concentration range of 3 orders of magnitude. We achieve hybrid integration of the enrichment strategy in a cartridge mold and a giant-magnetoresistance (GMR) sensor in a functionalized Quad Flat No-Lead (QFN) package, which allows for miniaturization of the Si footprint for potential low-cost bedside testing. The enrichment results demonstrate that TOF magnetic flow cytometry with adaptive particle focusing can match the clinical requirements for a point-of-care (POC) cytometer and can potentially be of interest for other sheath-less methodologies requiring workflow integration.

MEMS (micro electro mechanical system) based piston mirror arrays are key elements for real time computer generated holograms (CGH) in visualisation technologies like virtual, augmented and mixed reality (VR/AR/MR). The EU funded Project REALHOLO is developing a spatial light modulator (SLM) that is based on comb drive MEMS actuators that can fulfil the tight requirements of the optical and mechanical performance and the high level of integration. A previous design already outlined perspectives for a superior performance in comparison to other approaches for high frequency and high precision wave front modulation, but has restrictions due to the resolution and feature size of the i-line lithography system used for manufacturing. This paper discusses the optimisation of the design applying an advanced manufacturing process using DUV lithography that allows smaller features and therefore offers additional design options. By introducing an improved comb drive geometry the electrostatic force was significantly increased, which allowed the optimisation of other geometries, like horizontal and vertical gaps and additional shielding structures, for an even more linear actuator response and reduced crosstalk. The electrostatic and structural FEM simulations will show the significant improvements in overall performance, compared to the previous iteration and other types of SLMs. The improved actuator can potentially extend the field of application from the desired automotive driver assistance holographic 3D display to head mounted displays for VR, AR and MR applications as well as other technologies like material processing.

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