近日，武汉大学的郑国兴及其研究小组与南京大学的陈鹏等人合作并取得一项新进展。经过不懈努力，他们实现用于同时进行光谱测定和成像的电可调谐平面液晶单谱线。相关研究成果已于2024年9月9日在国际知名学术期刊《光：科学与应用》上发表。

该研究团队提出一种光谱单透镜，它将光学成像与计算光谱学功能融为一体，从而能够打造出极简、小型且高性能的高光谱相机。作为一种范例，研究人员利用平面液晶光学元件来实现所提出的框架，其中每个液晶单元既作为相位调制器，又作为电可调光谱滤波器。

对不同目标进行的实验表明，由此制成的毫米级高光谱相机展现出了高光谱保真度（>95%）和高空间分辨率（约为衍射极限的1.7倍）。所提出的“二合一”框架能够解决光谱分辨率与成像分辨率之间的冲突，为推动高光谱成像系统向小型化和便携式应用发展开辟了一条实用路径。

据悉，传统的高光谱相机通过级联透镜和光谱仪来获取光谱数据立方体，这构成了高光谱成像的基本框架。然而，当系统追求小型化时，这种级联框架会在光谱性能与成像性能之间产生权衡问题。

附：英文原文

Title: Electrically tunable planar liquid-crystal singlets for simultaneous spectrometry and imaging

Author: Zhou, Zhou, Zhang, Yiheng, Xie, Yingxin, Huang, Tian, Li, Zile, Chen, Peng, Lu, Yan-qing, Yu, Shaohua, Zhang, Shuang, Zheng, Guoxing

Issue&Volume: 2024-09-09

Abstract: Conventional hyperspectral cameras cascade lenses and spectrometers to acquire the spectral datacube, which forms the fundamental framework for hyperspectral imaging. However, this cascading framework involves tradeoffs among spectral and imaging performances when the system is driven toward miniaturization. Here, we propose a spectral singlet lens that unifies optical imaging and computational spectrometry functions, enabling the creation of minimalist, miniaturized and high-performance hyperspectral cameras. As a paradigm, we capitalize on planar liquid crystal optics to implement the proposed framework, with each liquid-crystal unit cell acting as both phase modulator and electrically tunable spectral filter. Experiments with various targets show that the resulting millimeter-scale hyperspectral camera exhibits both high spectral fidelity (>95%) and high spatial resolutions (~1.7 times the diffraction limit). The proposed “two-in-one” framework can resolve the conflicts between spectral and imaging resolutions, which paves a practical pathway for advancing hyperspectral imaging systems toward miniaturization and portable applications.

DOI: 10.1038/s41377-024-01608-w

Source: https://www.nature.com/articles/s41377-024-01608-w