Ultra‐fast and Universal Vector Mode Analyzer Based on 4D Jones Vector and Intensity‐Only Detection

Abstract The vast applications of vector vortex beams (VVBs) have driven the development of generation devices on various platforms and at different wavelengths, leading to a growing demand for universal optical field characterization methods. Simultaneously, high‐speed optical field characterization can be utilized for signal demodulation in information applications. In this paper, a universal and ultra‐fast vector mode decomposition (VMD) method based on purely analytical, non‐iterative formulas is proposed for the first time. This method requires only the intensity measurements of a few polarization components to achieve a complete 2D electric field characterization of VVBs. By utilizing the conversion relationships between different mode bases, this approach is compatible with various mode types—such as cylindrical vector (CV) and linearly polarized (LP) modes—across fibers, on‐chip waveguides, and other platforms. It is not limited by azimuthal or radial mode orders (determined only by detector resolution), and operates over 100 000 times faster than previous neural network methods. This universal and rapid method is expected to facilitate the characterization of vector‐structured beams and their practical applications in telecommunications, higher‐dimensional quantum information, and beyond.