Joint enhancement of saturation intensity and dynamic range forpolarization imaging via a polarization modulation aperture

Strong light exceeding the saturation intensity threshold and the dynamic range of imaging systems leads to overexposure and severe image degradation. Current approaches generally rely on intricate hardware setups, sophisticated algorithms, or multi-exposure strategies, which often bring about bulky systems, high computational costs, and limited adaptability. In this work, we propose what is believed to be a novel method to simultaneously enhance the saturation intensity and the dynamic range of a polarization imaging system by introducing a low-cost polarization modulation aperture (PMA). The core principle is to reduce the intensity reaching the camera by modulating the proportion of polarization components in the incoming light. This allows the actual intensity to be retrieved from a single capture via simple linear demodulation. By directly integrating the thin PMA directly into the lens assembly, our method avoids elaborate hardware alterations or computationally intensive post-processing. Moreover, the attenuation level can be adjusted by configuring the area ratios and polarization modulation directions of the sub-apertures within the PMA, ensuring optimized performance across diverse scenarios. Experiments show that, with a customized PMA using prior scene information, the prototype improves the saturation intensity by 680% and the effective dynamic range, meaning the system’s recoverable intensity range, by 17 dB in indoor strong light. In contrast, a generic PMA without prior information yields 200% and 6 dB gains in non-prior scenarios. Our method thus provides a compact, efficient, and cost-effective solution for achieving single-shot, high-quality polarization imaging under strong light conditions, particularly in environments with distinct polarization characteristics.