Compact optical polarization-insensitive zoom metalens-doublet
Abstract
Metasurface-based lenses (metalenses) offer specific conceptual advantages compared to ordinary refractive lenses. For example, it is possible to tune the focal length of a metalens doublet by varying the relative angle between the two metalenses while fixing their distance, leading to an extremely compact zoom lens. An improved polarization-insensitive design based on silicon-nanocylinders on silica substrates is presented. This design is realized and characterized experimentally at 1550 nm wavelength. By varying the relative angle between the metalenses in steps of 10 degrees, tuning of the doublet focal length is demonstrated from -54 mm to -+3 mm to +54 mm. This results in a zoom factor of an imaging system varying between 1 and 18. For positive focal lengths, the doublet focusing efficiency has a minimum of 34% and a maximum of 83%. Experiment and theory are in very good agreement.
Cite
@article{arxiv.2001.05913,
title = {Compact optical polarization-insensitive zoom metalens-doublet},
author = {Yunxuan Wei and Yuxi Wang and Xing Feng and Shunyuan Xiao and Zhaokun Wang and Tie Hu and Manchen Hu and Martin Wegener and Ming Zhao and Jinsong Xia and Zhenyu Yang},
journal= {arXiv preprint arXiv:2001.05913},
year = {2020}
}