Breaking Optical Transparency and Electromagnetic Performance Trade‐Offs for Transparent Reflective Metasurfaces

Achieving wideband electromagnetic wave manipulation while maintaining high optical transparency is crucial for the advancement of integrated microwave and optical systems. In this work, a transparent reflective metasurface (TRM) based on planar fine‐metal‐line (FML) resonant unit cells is presented, enabling efficient microwave reflection while maintaining high optical transparency. The presented structure supports wideband, polarization‐independent anomalous reflection over a wide range of incidence angles. In addition, the optical transparency can be tailored through the FML line width without eroding reflection performance. As the first of its kind, the metasurface achieves very high optical transparency and consistent wideband anomalous reflections with large incident angles up to the grazing incidence. Experimental results from a fabricated prototype using a 100 µm‐width metal line demonstrate an average optical transparency of 73% and stable beam redirection from 25.5 to 34.5 GHz (30% bandwidth). System‐level validation further confirms reliable communication links under various modulation schemes, including 8‐PSK and 16‐QAM, when the developed TRM is mounted on glass. This metasurface technology introduces a new paradigm for microwave wavefront control with high optical transparency, offering promising capabilities for seamless integration into next‐generation optoelectronic systems.