High-resolution wavefront detection using binary phase grating modulation for large dynamic range

Conventional Shack-Hartmann wavefront sensors (SHWFS) struggle to balance wavefront reconstruction accuracy and dynamic range under limited sub-aperture pixel arrays. In response to this, we innovatively propose a SHWFS based on binary phase grating modulation. The principle is that by mapping the tilt phase onto the binary phase, the amount of information of the spot image can be effectively increased, thereby enhancing the wavefront detection accuracy. This method resolves the accuracy-dynamic range trade-off, enabling high-precision detection under the condition of a low-pixel array. This paper thoroughly investigates the influence of various design parameters of the binary phase grating on the wavefront reconstruction accuracy. Simulation and experimental results demonstrate that the proposed method achieves high-precision wavefront detection with a sub-aperture pixel array of only 4 × 4 and a large dynamic range with a short focal length microlens array (MLA).