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In recent years there has been an increasing interest to integrate optical sensing in mobile displays, for instance, for biometric fingerprint scanning functionality. There are several routes to incorporate optical fingerprint functionality within the full display area, each with their own benefits and challenges. Here we investigate the different integration routes using large‐area, ultra‐thin imagers based on organic photodiodes. [ABSTRACT FROM AUTHOR]

Going towards high‐resolution, uniform displays with a high‐brightness range requires optimizations on different topics. This work presents an overview on this subject. To achieve a good uniformity, a compensation method is proposed using a 2T1C pixel circuit, compatible with high‐resolution requirements, improving uniformity by a factor 52.5. In order to further increase the achievable resolution, a new technology stack, using a planar and a vertical TFT is introduced. For increasing the brightness range, a global dimming method, compatible with the 2T1C pixel circuit, is demonstrated. [ABSTRACT FROM AUTHOR]

Two different external compensation methods for high‐resolution active matrix organic light‐emitting diode (AMOLED) displays are presented and compared. Both compensation methods are implemented using a small pixel circuit, namely, a 3T2C and a 2T1C pixel circuit, allowing high‐resolution displays. Due to the simple driving schemes, these methods allow fast driving, even for large displays. The characterization results show a significant improvement in current variation by implementing either of these methods. The VT compensation method using a 3T2C pixel circuit is able to reduce the current variation down to 0.56%, whereas the VT‐ and β‐factor compensation method using a 2T1C pixel circuit demonstrates a further reduction in current variations down to 0.079%. This method also clearly shows significant improvement in optical variation between neighboring pixels. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This paper presents a new compensation principle using a 2T1C pixel circuit. The implementation shows significant improvement in uniformity for all grey‐levels, due to compensation for both VT and β‐factor variations. The resulting current variation after compensation in the characterized display area reaches values down to 0.079%. [ABSTRACT FROM AUTHOR]

A novel external VT compensation method, using a simple driving scheme, is presented, enabling high resolution, yet uniform displays, regardless of the size. The uniformity can be maintained for initial VT nonuniformities as well as VT shifts occurring during operation, like bias stress. The characterized display area shows a significant reduction in current variation, transforming ~23% variation without compensation into 0.56% variation after calibration. [ABSTRACT FROM AUTHOR]

High resolution ESJET printing is presented for processing of OLED devices. With appropriate nozzle geometry and driving schemes pixel structures of 10 µm and below are achievable with the final goal of printing a 310 ppi RGB AMOLED display. [ABSTRACT FROM AUTHOR]