Lee Dongwoo, Oh Beomseok, Park Jeonghoon, Moon Seong-Won, Shin Kilsoo, Kim Sea-Moon, Rho Junsuk
Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
Ocean and Maritime Digital Technology Research Division, Korea Research Institute of Ships & Ocean Engineering (KRISO), Daejeon, 34103, Republic of Korea.
Nat Commun. 2024 Apr 8;15(1):3044. doi: 10.1038/s41467-024-47050-9.
Metalenses are instruments that manipulate waves and have exhibited remarkable capabilities to date. However, an important hurdle arises due to the severe hampering of the angular response originating from coma and field curvature aberrations, which result in a loss of focusing ability. Herein, we provide a blueprint by introducing the notion of a wide field-of-hearing (FOH) metalens, designed particularly for capturing and focusing sound with decreased aberrations. Employing an aberration-free planar-thin metalens that leverages perfect acoustic symmetry conversion, we experimentally realize a robust wide FOH capability of approximately 140 in angular range. Moreover, our metalens features a relatively short focal length, enabling compact implementation by reducing the aperture-to-hearing plane distance. This is beneficial for space-efficient source-tracking sound sensing. Our strategy can be used across various platforms, potentially including energy harvesting, monitoring, imaging, and communication in auditory, ultrasonic, and submerged environments.
超颖透镜是一种操控波的仪器，迄今为止已展现出卓越的性能。然而，由于彗差和场曲像差严重阻碍角响应，导致聚焦能力丧失，这成为一个重要障碍。在此，我们通过引入宽听觉场（FOH）超颖透镜的概念提供了一个蓝图，该超颖透镜专为捕获和聚焦声音而设计，具有减少的像差。利用利用完美声学对称转换的无像差平面薄超颖透镜，我们通过实验实现了约140°角范围内强大的宽FOH能力。此外，我们的超颖透镜具有相对较短的焦距，通过减小孔径到听觉平面的距离实现紧凑设计。这有利于空间高效的源跟踪声音传感。我们的策略可用于各种平台，可能包括听觉、超声和水下环境中的能量收集、监测、成像和通信。
