Metasurface-Driven Adaptive Structured Light: Achieving Integrated Real-Time 3D Reconstruction and Forward Ranging in...

In structured light-based three-dimensional (3D) reconstruction technology, normal and grazing emission beams hold significant application value due to their stable axial propagation characteristics and anti-distortion advantages. However, current systems face two major technical bottlenecks. First, traditional grazing emission beams depend on the precise assembly of complex optical components, which compromises reliability and impedes miniaturization. Second, the physical constraints of light field transmission make it challenging to generate both modes simultaneously within a single system. This study exploits the light waves modulation capabilities of metasurface to achieve the simultaneous generation of normal and grazing emission dual-mode beams. Specifically, an adaptive closed-line structured light with a central bright spot is generated within 2π space. By integrating a self-developed multimodal point cloud enhancement algorithm, a 3D reconstruction and forward ranging system adaptable to diverse scenarios has been successfully developed. This system achieves real-time 3D reconstruction and forward ranging at 30 fps without additional ranging modules. This technology not only transforms the hardware architecture of existing structured light systems and surpasses the limit of light emission angles but also overcomes the application constraints of traditional methods in diverse scenarios. It provides innovative technological support and solutions for the digital construction of tunnel engineering.