Human eyes possess exceptional image-sensing characteristics such as an extremely wide field of view, high resolution and sensitivity with low aberration1. Biomimetic eyes with such characteristics are highly desirable, especially in robotics and visual prostheses. However, the spherical shape and the retina of the biological eye pose an enormous fabrication challenge for biomimetic devices2,3. Here we present an electrochemical eye with a hemispherical retina made of a high-density array of nanowires mimicking the photoreceptors on a human retina. The device design has a high degree of structural similarity to a human eye with the potential to achieve high imaging resolution when individual nanowires are electrically addressed. Additionally, we demonstrate the image-sensing function of our biomimetic device by reconstructing the optical patterns projected onto the device. This work may lead to biomimetic photosensing devices that could find use in a wide spectrum of technological applications.
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The data that support the findings of this study are provided in the main text and the Supplementary Information. More data are available from the corresponding author upon reasonable request.
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This work was supported by the National Natural Science Foundation of China (project 51672231) and the Science and Technology Plan of Shenzhen (JCYJ20170818114107730), the General Research Fund (projects 16237816, 16309018 and 16214619) from the Hong Kong Research Grant Council, Hong Kong Innovation Technology Commission (project ITS/115/18) and The Hong Kong University of Science and Technology (HKUST) Fund of Nanhai (grant number FSNH-18FYTRI01). We acknowledge support received from the Material Characterization and Preparation Facility (MCPF, particularly Y. Cai for her technical assistance with the focused ion beam), the Nanosystem Fabrication Facility (NFF), the Center for 1D/2D Quantum Materials and the State Key Laboratory on Advanced Displays and Optoelectronics at HKUST. We also thank D. Wang (Chemistry Department, Boston College), M. Shao (Department of Chemical and Biological Engineering, HKUST) and Q. Chen (Department of Mechanical and Aerospace Engineering, HKUST) for their discussions on the electrochemical impedance spectroscopy measurements. The images in Fig. 1a–d and Supplementary Fig. 1 were created by Fantastic Color Animation Technology Co., Ltd (2020).
The authors declare no competing interests.
Peer review information Nature thanks Dae-Hyeong Kim, Hongrui Jiang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Supplementary Methods, Discussions and Table. This file contains Supplementary Sections 1-27. It includes more details on preparation and characterization of perovskite NWs, the device assembly, mechanism discussion and image sensing characterization of individual and arrayed NWs based photodetectors, hemispherical EC-EYEs and integrated EC image sensors.
The dynamic process of EC-EYE capturing letters character patterns.
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Gu, L., Poddar, S., Lin, Y. et al. A biomimetic eye with a hemispherical perovskite nanowire array retina. Nature 581, 278–282 (2020). https://doi.org/10.1038/s41586-020-2285-x
Extreme Mechanics Letters (2020)