Wearable III-nitride optoelectronic chip for gesture recognition.

Wearable III-nitride optoelectronic chips with monolithically integrated optical transmitters and receivers have emerged as a low-cost and highly portable platform for light-based sensing systems. III-nitride-based multiple quantum well (MQW) diodes inherently exhibit overlapping emission and detection spectra due to multiple energy levels within the MQW active region, with a spectral overlap from 481.54 nm to 534.03 nm. Here, we develop III-nitride optoelectronic chips for a wearable gesture recognition system using light. Together with a flexible programmable circuit, identical MQW diodes on a single III-nitride chip separately function as optical transmitters and receivers, enabling a reflective sensing architecture in a wearable optical system. These chips are integrated into a wearable platform attached to the fingers to establish optical sensing links. External finger motions modulate the emitted light, which is reflected back to the monolithically integrated MQW receiver. The encoded light is converted into electronic signals and processed by a multilayer perceptron for dynamic gesture recognition.