Two-dimensional optical spatial differentiation and high-contrast imaging

• Published in: National science review 2021-06, Vol.8 (6), p.nwaa176-nwaa176
• Main Authors: Zhou, Junxiao, Qian, Haoliang, Zhao, Junxiang, Tang, Min, Wu, Qianyi, Lei, Ming, Luo, Hailu, Wen, Shuangchun, Chen, Shaochen, Liu, Zhaowei
• Format: Article
• Language: English
• ISSN: 2095-5138; 2053-714X
• DOI: 10.1093/nsr/nwaa176

Abstract Optical analog signal processing technology has been widely studied and applied in a variety of science and engineering fields, with the advantages of overcoming the low-speed and high-power consumption associated with its digital counterparts. Much attention has been given to emerging metasurface technology in the field of optical imaging and processing systems. Here, we demonstrate, for the first time, broadband two-dimensional spatial differentiation and high-contrast edge imaging based on a dielectric metasurface across the whole visible spectrum. This edge detection method works for both intensity and phase objects simply by inserting the metasurface into a commercial optical microscope. This highly efficient metasurface performing a basic optical differentiation operation opens up new opportunities in applications of fast, compactible and power-efficient ultrathin devices for data processing and biological imaging. High-contrast broadband two-dimensional edge detection is demonstrated for both the intensity and phase objects, which brings fast and power-efficient metasurfaces for optical information processing and imaging one step closer to the reality.