In-Sensor Polarization Convolution Based on Ferroelectric-Reconfigurable Polarization-Sensitive Photodiodes

In-sensor computing can enhance the imaging system performance by putting part of the computations into the sensor. While substantial advancements have been made in latency, spectral range, and functionalities, the strategy for in-sensor light polarization computing has remained unexplored. Here, it is shown that ferroelectric-reconfigurable polarization-sensitive photodiodes (FPPDs) based on BiFeO₃ nanowire arrays can perform in-sensor computations on polarization information. This innovation leverages the anisotropic photoresponse from the 1D structure of nanowires and the non-volatile reconfigurability of ferroelectrics. The devices show programmable anisotropic ratios as high as 5219, surpassing most state-of-the-art polarization-sensitive photodetectors and commercial polarization image sensors. Employing tunable photoresponse as kernel, FPPDs can perform convolutions to directly extract feature maps containing polarization information, which raises the recognition accuracy on road-scene objects under adverse weather up to 89.6%. The research highlights the potential of FPPDs as a highly efficient vision sensor and extends the boundaries of advanced intelligent imaging systems.