Large dynamic range Shack-Hartmann wavefront sensor based on adaptive spot matching

• Published in: Light: advanced manufacturing Vol. 4; no. 1; pp. 1 - 10
• Main Authors: Yang, Jiamiao, Zhou, Jichong, Qiu, Lirong, Shao, Rongjun, Liu, Linxian, He, Qiaozhi
• Format: Journal Article
• Language: English
• Published: Light Publishing Group 2024
• Subjects: large dynamic range; shack-hartmann sensor; wavefront sensing
• ISSN: 2831-4093; 2689-9620
• DOI: 10.37188/lam.2024.007

The Shack-Hartmann wavefront sensor (SHWS) is widely used for high-speed, precise, and stable wavefront measurements. However, conventional SHWSs encounter a limitation in that the focused spot from each microlens is restricted to a single microlens, leading to a limited dynamic range. Herein, we propose an adaptive spot matching (ASM)-based SHWS to extend the dynamic range. This approach involves seeking an incident wavefront that best matches the detected spot distribution by employing a Hausdorff-distance-based nearest-distance matching strategy. The ASM-SHWS enables comprehensive spot matching across the entire imaging plane without requiring initial spot correspondences. Furthermore, due to its global matching capability, ASM-SHWS can maintain its capacity even if a portion of the spots are missing. Experiments showed that the ASM-SHWS could measure a high-curvature spherical wavefront with a local slope of 204.97 mrad, despite a 12.5% absence of spots. This value exceeds that of the conventional SHWS by a factor of 14.81.