近日，韩国科学技术院(KAIST)的Mooseok Jang及其研究团队取得一项新进展。经过不懈努力，他们研制出用于复杂物体相位成像的，具有大采样密度和大角度视场的Meta Shack-Hartmann波前传感器。相关研究成果已于2024年8月12日在国际知名学术期刊《光：科学与应用》上发表。

据悉，Shack-Hartmann波前传感器基于透镜阵列产生的焦点位移来测量入射波前的局部斜率，是天文和生物医学成像中自适应光学的关键部件。传统上，提高透镜阵列密度和曲率的挑战，限制了这类波前传感器在表征缓慢变化的波前结构方面的应用。

在此，该研究团队考虑到透镜阵列参数与Shack-Hartmann波前传感器（SHWFS）性能之间的相互作用，开发了一种超表面增强的Shack-Hartmann波前传感器（meta SHWFS），以打破这一限制。研究人员实验验证了采样密度为5963每平方毫米、最大接收角为8°的meta SHWFS，其性能优于传统SHWFS达一个数量级。

此外，据研究人员所知，他们首次展示了波前传感方案在单次拍摄高复杂度模式相位成像中的应用，包括生物组织模式。该方法为在复杂波前表征中融入超表面平台的卓越光操控能力开辟了新机遇。

附：英文原文

Title: Meta Shack–Hartmann wavefront sensor with large sampling density and large angular field of view: phase imaging of complex objects

Author: Go, Gi-Hyun, Lee, Dong-gu, Oh, Jaeyeon, Song, Gookho, Lee, Doeon, Jang, Mooseok

Issue&Volume: 2024-08-12

Abstract: Shack–Hartmann wavefront sensors measure the local slopes of an incoming wavefront based on the displacement of focal spots created by a lenslet array, serving as key components for adaptive optics for astronomical and biomedical imaging. Traditionally, the challenges in increasing the density and the curvature of the lenslet have limited the use of such wavefront sensors in characterizing slowly varying wavefront structures. Here, we develop a metasurface-enhanced Shack–Hartmann wavefront sensor (meta SHWFS) to break this limit, considering the interplay between the lenslet parameters and the performance of SHWFS. We experimentally validate the meta SHWFS with a sampling density of 5963permm² and a maximum acceptance angle of 8° which outperforms the traditional SFWFS by an order of magnitude. Furthermore, to the best of our knowledge, we demonstrate the first use of a wavefront sensing scheme in single-shot phase imaging of highly complex patterns, including biological tissue patterns. The proposed approach opens up new opportunities in incorporating exceptional light manipulation capabilities of the metasurface platform in complex wavefront characterization.

DOI: 10.1038/s41377-024-01528-9

Source: https://www.nature.com/articles/s41377-024-01528-9