Experimental Halide Perovskite LED Combines Touch Interaction With Fingerprint Recognition

Scientists at Linköping University (LiU) in Sweden have developed LED digital display technology using halide perovskite, which integrates touch, fingerprint recognition, and pulse detection capabilities directly into the screen. Still in the prototype stage, the technology could significantly alter the interaction between users and personal electronic devices by eliminating the need for separate sensors for different functions.

Halide perovskites are a class of crystal-like materials characterized by their unique perovskite structure, typically composed of a metal halide bonded to an organic or inorganic cation. They have attracted considerable attention in recent years due to their impressive optoelectronic properties, which include high light absorption, efficient charge transport, and tunable bandgaps.

These features make halide perovskites highly effective in applications such as solar cells, light-emitting diodes (LEDs), and photodetectors. Their ease of fabrication and potential for low-cost production further enhance their appeal in the field of advanced electronic and photonic devices.

By engineering the properties of perovskite materials within a device display, the Linköping researchers have enabled the detection and response to various stimuli, such as touch, fingerprints, and even the pulse of a user. The integration is achieved by using the sensitive light-emitting and electrical properties of perovskites that can be altered by different physical pressures and electrical conductivities associated with touch and pulse. This sensitivity allows the display to register and react to biometric inputs directly, thereby streamlining device functionality and enhancing user interaction without the need for separate sensors or additional hardware, simplifying the overall device structure and potentially reducing costs and complexity.

That having been said, a serious downside lies in the material’s inherent instability. Perovskites are sensitive to environmental factors such as moisture, temperature, and light exposure, which can lead to rapid degradation and a decrease in device performance over time. This instability manifests in the LEDs losing effectiveness after only a few hours of operation, as the perovskite material becomes unstable and the light-emitting properties diminish.

While the research team has demonstrated the potential for innovative multifunctional displays, a key focus moving forward is to improve the stability of perovskite materials to ensure that they can be used reliably in everyday devices for extended periods.

Still, researcher Feng Gao emphasized that his team has “now shown that our design principle works.”

“Our results show that there is great potential for a new generation of digital displays where new advanced features can be created,” he said. “From now on, it’s about improving the technology into a commercially viable product.”

Source: Interesting Engineering

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April 15, 2024 – by Alex Perala and the FindBiometrics Editorial Team