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Touchless technology based on user interaction modes such as voice or gestures is paving the way for tomorrow’s digital ecosystems, accelerated by hygiene requirements resulting from the COVID-19 pandemic. Gesture-based touchless user interfaces typically use near-infrared (NIR) cameras. The applicability of these systems is hampered by their limitations in field of view and their calibration requirements for high accuracy. Here, we show a novel touchless user interface based on a large-area visually transparent NIR-sensitive 16 × 16 organic photodetector (OPD) array that can be used on top of a display as a touchless user interface. Optical transparency is realized by implementing a printed copper (Cu) grid as a bottom transparent conductive electrode (TCE) and an array of patterned OPD subpixels. Electro-optical modelling enabled an optimal image sensor design that resulted in a high photodetectivity of ca. 1012 Jones at 850 nm and high visible-light transmittance of 70%. We demonstrate that our imager can be used as a penlight- and gesture controlled touchless user interface when combined with a commercial display.

This paper presents a monolithic manufacturing process to realize active-matrix meshed TFT arrays on foil with physical voids between pixels, realizing membrane-like structures for use in biometrics-under-display applications. Moreover, however, the concept enables new applications in the biomedical electronics domain.

A monolithic manufacturing process is presented for the realization of active-matrix meshed thin-film-transistor (TFT) arrays on foil with physical voids between pixels, realizing membrane-like electronic arrays. The process is scalable to large-area substrates and enables (improved performance of) biometrics-under-display applications. Moreover, membrane-like TFT arrays provide opportunities for the use of TFT technology, and broader large-area thin-film electronics, in new applications in the domain of biomedical electronics, as demonstrated by example use cases of in vivo electrophysiology of the brain as well as in vitro electrophysiology in smart microwell plates.

We combine a low dark current and high-detectivity near-infrared (NIR)-sensitive organic photodetector with a high-resolution 508 pixels per inch (ppi) oxide thin-film transistor (TFT) backplane to create a large-area thin NIR detector, using processes that are compatible with flat-panel display fabrication. The detector is characterized showing high uniformity and linearity. With the use of a NIR light source, the detector is capable of imaging the (pattern of) veins under the skin in reflection, leading to improved biometric authentication.

We present large-area photodetector arrays in combination with a thin-film optical collimator for under-display fingerprint authentication in next-generation smartphones. The fabrication is compatible with flat panel display processes and based on an oxide TFT backplane with a printed organic photodiode frontplane. The functionality behind an AMOLED display is demonstrated.

We present a thin-film dual-layer bottom barrier on polyimide that is compatible with 350°C backplane processing for organic light-emitting diode displays and that can facilitate foldable active-matrix organic light-emitting diode devices with a bending radius of

We present a qHD (960 × 540 with three sub-pixels) top-emitting active-matrix organic light-emitting diode display with a 340-ppi resolution using a self-aligned IGZO thin-film transistor backplane on polyimide foil with a humidity barrier. The back plane process flow is based on a seven-layer photolithography process with a CD = 4 μm. We implement a 2T1C pixel engine and use a commercial source driver IC made for low-temperature polycrystalline silicon. By using an IGZO thin-film transistor and leveraging the extremely low off current, we can switch off the power to the source and gate driver while maintaining the image unchanged for several minutes. We demonstrate that, depending on the image content, low-refresh operation yields reduction in power consumption of up to 50% compared with normal (continuous) operation. We show that with the further increase in resolution, the power saving through state retention will be even more significant.

We use sALD to deposit IGZO and Al2O3 layers in top-gated self-aligned TFTs, achieving a low-temperature process flow (d200oC). We attain mobility of 8 cm2/Vs and switch-on voltage of -0.1 V for transistors with channel lengths down to 1 μm, enabling a 200 ppi QVGA display on transparent PEN foil.

We present a qHD (960x540 with 3 sub-pixels) top-emitting AMOLED display with 340ppi resolution using a self-aligned (SA) IGZO TFT backplane on polyimide-foil with humidity barrier. The back plane process flow is based on a 7 layer photolithography process with a CD=4um. We implement a 2T1C pixel engine and use commercial source driver IC made for LTPS. By using IGZO TFT and leveraging the extremely low off-current, we can switch-off the power to the source and gate driver while maintaining the image un-changed for several minutes. We demonstrate that, depending on the image content, low-refresh operation yields reduction in power consumption of up to 50% compared to normal (continuous) operation. We show that with further increase in resolution, the power saving through state retention will be even more significant.

A kinetic study was carried out on the regio- and stereoselectivities of 12 lipases of animal and microbial origin. For this purpose, monomolecular films consisting of three pairs of enantiomers (didecanoyl-deoxyamino-O methyl glycerol, DDG) containing a single hydrolyzable decanoyl ester bond and two lipase-resistant groups were spread at the air-water interface. Each of the lipases tested displayed a particular type of behavior, on the basis of which they were classified in two groups, depending on their ability to hydrolyze the sn-2 position. From the qualitative point of view, the sn-2 preference measured on triacylglycerides and DDG were in good agreement. The inductive chemical effect might explain why a greater level of hydrolytic activity was observed with the diglycerides than with DDG. With most of the lipases tested, it was observed that the enantiomeric pair having two distal acyl chains was more clearly differentiated stereochemically than the two homologous pairs with two adjacent acyl chains. This finding is consistent with the hypothesis that during the chiral recognition process two of the three attachment points may be the external (distal) hydrophobic chains, which is in line with the hypothesis of a tuning fork conformation of a triglyceride in the lipase active site.