A supercritical lens(SCL) can achieve far-field sub-diffraction-limited focusing by elaborately manipulating the interference effect in the focal region, which makes it strongly dependent on the wavelength of the illu...A supercritical lens(SCL) can achieve far-field sub-diffraction-limited focusing by elaborately manipulating the interference effect in the focal region, which makes it strongly dependent on the wavelength of the illuminating light. In addition to the strong chromatic aberrations it suffers, the micrometer-scale clear aperture of reported SCL represents another compelling challenge that excludes their practical imaging applications demand. In this work, we proposed and experimentally demonstrated an achromatic supercritical lens(ASCL) with a centimeterscale clear aperture. The ASCL was designed by a two-step optimization algorithm and constructed in a multilevel phase configuration which consists of 1251 concentric polymer rings with 52 phase levels. By utilizing the grayscale laser lithography technique, we successfully fabricated an ASCL with a diameter of 10 mm. Such a centimeter-scale ASCL showcases a distinguished performance with full visible working bandwidth covering from 400 nm to 700 nm and simultaneous achromatic sub-diffraction-limited focusing of 0.88 times of the Airy spot.The demonstrations of white light microscopic imaging further validate our design and show decent performance.Our work paves the way for practical applications of SCL in high-density optical data storage, super-resolving optical telescope, and high-precision optical trapping.展开更多
基金National Key Research and Development Program of China(2023YFF0718101)National Natural Science Foundation of China(62475102,62375109,62275108)Basic and Applied Basic Research Foundation of GuangdongProvince(2020B1515020058).
文摘A supercritical lens(SCL) can achieve far-field sub-diffraction-limited focusing by elaborately manipulating the interference effect in the focal region, which makes it strongly dependent on the wavelength of the illuminating light. In addition to the strong chromatic aberrations it suffers, the micrometer-scale clear aperture of reported SCL represents another compelling challenge that excludes their practical imaging applications demand. In this work, we proposed and experimentally demonstrated an achromatic supercritical lens(ASCL) with a centimeterscale clear aperture. The ASCL was designed by a two-step optimization algorithm and constructed in a multilevel phase configuration which consists of 1251 concentric polymer rings with 52 phase levels. By utilizing the grayscale laser lithography technique, we successfully fabricated an ASCL with a diameter of 10 mm. Such a centimeter-scale ASCL showcases a distinguished performance with full visible working bandwidth covering from 400 nm to 700 nm and simultaneous achromatic sub-diffraction-limited focusing of 0.88 times of the Airy spot.The demonstrations of white light microscopic imaging further validate our design and show decent performance.Our work paves the way for practical applications of SCL in high-density optical data storage, super-resolving optical telescope, and high-precision optical trapping.
