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Microlens arrays (MLAs) have a variety of applications in, e.g., display systems, projection optics, and sensors. They can be manufactured by various fabrication methods. Among all, inkjet printing stands out because it offers a straightforward, versatile, and low‐cost fabrication route. However, extra manufacturing steps such as photolithography are so far involved to pre‐structure the substrate in order to improve the uniformity of the printed MLAs and achieve a high fill factor (FF). In this study, the fabrication of MLAs is reported on unstructured substrates by inkjet printing using an optimized UV‐curable ink on top of self‐assembled monolayers (SAMs). The latter allows for tuning the surface free energy and thus the aspect ratio of the microlenses. The high uniformity of the printed MLAs is demonstrated by the automatic quantitative evaluations, where the standard deviations of the radii are below 2.5% and of the sag heights are less than 3.9%. An unprecedented FF of 88% amongst all inkjet‐printed MLAs on unstructured substrates is achieved. Digitally controlled large area fabrication is demonstrated, both, on rigid as well as on flexible substrates, opening a pathway for customized microoptics by additive manufacturing. [ABSTRACT FROM AUTHOR]

Mechanoresponsive smart windows have been intensively investigated in recent years as they offer various applications for signage and light management. However, integrating a display functionality into such smart windows remains a challenge since the realization of pixels in these devices is difficult. In addition, mechanoresponsive smart windows with a high dynamic range are rarely demonstrated because they would suffer from complex fabrication processes and high costs. In this work, a novel surface modification process and digital encoding were developed for direct inkjet printing of micro‐etching‐masks on hydrophobic elastomers, and a pixelated haze distribution was realized. Compared to the traditional mechanoresponsive smart windows, which modify the optical performance by applied strain solely, here, a smart window with haze tunability in either static or strain‐applied state is demonstrated. The work enhances the potential of the fabricated smart window to be applied in high dynamic range signage displays. [ABSTRACT FROM AUTHOR]

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