We present a kind of large effective aperture metalens based on an optical sparse aperture(OSA) system. Each subaperture of the system is a metalens, which is comprised of just a thin Au film with patterned subwavelen...We present a kind of large effective aperture metalens based on an optical sparse aperture(OSA) system. Each subaperture of the system is a metalens, which is comprised of just a thin Au film with patterned subwavelength rectangular annular arrays on a Si O2 substrate and has a numerical aperture of 0.46 with a diameter of 21.6 μm.Ring6 design was selected to enlarge the effective aperture and enhance the spatial resolution. Compared with the absent mid-frequency and high-frequency modulation transfer function of individual metalens, Ring6 can offer a full-frequency band and show a better restored image quality by using Tikhonov regularization.展开更多
基金partially supported by the Intergovernmental International Cooperation Program in Science and Technology Innovation (No. 2016YFE0110600)International Science&Technology Cooperation Program of Shanghai (No. 16520710500)+4 种基金National Natural Science Foundation of China (No. 61805264)Youth Innovation Promotion Association CASScience and Technology Commission of Shanghai Municipality(No. 17YF1429500)Shanghai Sailing Program(No. 18YF1426500)University Scientific Research Foundation of Jiangsu Province (No. KJS1713)
文摘We present a kind of large effective aperture metalens based on an optical sparse aperture(OSA) system. Each subaperture of the system is a metalens, which is comprised of just a thin Au film with patterned subwavelength rectangular annular arrays on a Si O2 substrate and has a numerical aperture of 0.46 with a diameter of 21.6 μm.Ring6 design was selected to enlarge the effective aperture and enhance the spatial resolution. Compared with the absent mid-frequency and high-frequency modulation transfer function of individual metalens, Ring6 can offer a full-frequency band and show a better restored image quality by using Tikhonov regularization.