Chip-integrated metasurface with double-helix point spread functions for ultra-large dynamic range wavefront sensing.

Wavefront sensing underpins diverse optical technologies, requiring compact sensors with large dynamic range, high spatial sampling density, and photonic integration. Conventional Shack-Hartmann sensors offer only ~±1° intrinsic geometric dynamic range, ~10 sub-apertures per millimeter, and cannot resolve polarization-dependent wavefronts. Existing metasurface-based approaches still require external imaging optics, preventing true on-chip integration. Critically, both schemes suffer from an inherent trade-off between dynamic range and sampling density. Here, we present the first chip-integrated metasurface Shack-Hartmann sensor operating directly on a complementary metal oxide semiconductor image sensor without external optics. Our dual-encoding strategy uses orientation-encoded double-helix point spread functions to extend the dynamic range to ±9.4° per channel without degrading sampling density, while orthogonal circular polarization channels with distinct lobe separations double the sampling density without sacrificing dynamic range. The architecture inherently supports vectorial wavefront sensing. We demonstrate three-dimensional localization of point source, lens profilometry, and video-rate dynamic wavefront monitoring, establishing a scalable platform for alignment-free, high-performance metrology.