Compact Wide-Field-of-View Near-Infrared Incident-Direction Sensing System Based on a Diffractive Optical Element

In this study, we present the first experimental demonstration of a compact incident-direction sensing system. The system is based on a diffractive optical element (DOE) lens designed for wide field-of-view (FOV) applications in the near-infrared spectral range. The DOE lens maps incident angles onto distinct focal positions on a single detector plane. This approach achieves nearly double the FOV compared with conventional lens-based systems. The system is validated via both simulation and experiment, showing strong agreement across the tested angular range. With the proposed system, broader angular coverage can be realized through advances in microfabrication techniques or by adopting metalens-based designs. This study demonstrates the potential of DOE-based solutions for wide-angle, miniaturized sensing in next-generation smart devices.