A touchless user interface based on a near-infrared sensitive transparent optical imager using printed Cu grid electrodes.

Abstract

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.

Remarkable Isomer Effect on the Performance of Fully Non‐Fused Non‐Fullerene Acceptors in Near‐Infrared Organic Photodetectors

“…[66,67] We note that performing the characterization at a large reverse bias is important to correctly evaluate the figures of merit (see further discussion in Supporting Information). [68][69][70] D* is another fundamental parameter of photodetectors and is usually employed to assess the lightdetecting sensitivity (Figure 3c), which can be given by the Equation ( 4)…”

Suppressing the Dark Current While Improving the Quantum Efficiency in Shortwave Infrared Organic Photodetectors Through Naphthalenediimide‐Based Interlayer

“…However, this issue does not pose a problem for silicon, glass, or polyimide substrates, such as image sensors integrated ROIC and inverted OPD. [16,29,12] Therefore, in this study, we focus on this cross-linkable NDI derivative and compare with the commonly used ZnO ETL, evaluating the feasibility of NDI-based interlayer in SWIR OPD devices. Leveraging the unique properties of NDI, the goal is to achieve suppressed J D and improved external quantum efficiency (EQE) in SWIR-responsive devices, ultimately leading to better device stability.…”

Contactless User‐Interactive Sensing Display for Human–Human and Human–Machine Interactions

“…[32] Kamijo et al reported a near-infrared-sensitive organic photodetector array that can detect near-infrared light reflected from the fingers and hands, enabling touchless gesture recognition and control. [33] However, these sensors capture information and transfer it into electrical signals; thus they cannot provide real-time visual feedback to the user owning to the absence of a light medium. To addressing this issue, the sensor is linked to a display via a microcontroller.…”