An ultra thin, bright, and sensitive interactive tactile display based on organic mechanoluminescence for dual-mode handwriting identification

Abstract

Visible light-based human–machine interactive media is capable of transmitting electrical readouts to machines and providing intuitive feedback to users simultaneously. Currently, many inorganic mechanoluminescent (ML) materials-based interactive media, typically ZnS-loaded phosphors (ZLPs), have been successfully demonstrated. However, organic ML materials-based solutions were rarely exploited despite their huge merits of strong structural modification, abundant luminescence property, low cost, easy preparation, and so on. Here, we propose a novel interactive tactile display (ITD) based on organic ML materials (Cz-A6-dye) and triboelectric nanogenerator, with ultra-brightness (130% enhancement) and ultra-low threshold pressure (57% reduction) as compared to ZLPs. The proposed ITD achieves the conversion of weak mechanical stimuli into visible light and electrical signals simultaneously, without extra power supplies. Furthermore, the relationship between the luminous performance of organic ML materials and mechanical force is quantified, benefiting from the uniform ML layer prepared. Enabled by convolutional neural networks, the high-accuracy recognition (97.1%) for handwriting and identity of users is realized at the same time. Thus, the ITD has great potential for intelligent wearable electronics and classified military applications.

Keywords

interactive media / organic mechanoluminescence / triboelectric nanogenerators

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