A Soft Mechanoluminescent Skin for High‐Resolution Optical Tactile Sensing in Human–Machine Interaction

ABSTRACT As soft interfaces become central to robotics, wearables, and human–machine interaction, a persistent challenge is to sense touch with high fidelity while keeping devices simple, robust, and negligible power requirement at the sensitive element. Herein, we report a soft mechanoluminescent (ML) tactile sensor converting force directly into light for imaging‐based readout, integrating a thin, three‐layer ML‐skin with a CMOS module. Under mechanical stimulation, BaTiO ₃ inclusions intensify local piezoelectric fields to excite ZnS:Cu emitters, producing light without electrical bias, pixel wiring, or external illumination. This optical transduction provides intrinsic electrical isolation while enabling scalable, high‐density spatial mapping, where resolution is defined by optics rather than electrode routing. Coupled to a 640 × 480, 30 Hz CMOS array, the ML‐sensor achieves a sensitivity of 27.5 N ⁻¹ , a 30 ms response time, ∼80 µm spatial resolution, and stable operation for over 8000 cycles. Furthermore, ML‐sensor enables real‐time handwriting recognition and human–machine interaction, demonstrating its potential as a natural tactile interface. By merging force‐to‐light conversion with a minimal device stack and vision‐native readout, this work outlines a pathway to energy‐efficient, conformal touch interfaces scalable across next‐generation soft electronics and interactive systems.