{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,2]],"date-time":"2025-11-02T09:39:51Z","timestamp":1762076391935,"version":"build-2065373602"},"reference-count":64,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,11,24]],"date-time":"2022-11-24T00:00:00Z","timestamp":1669248000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["12272100","11862003","81860635","12062005"],"award-info":[{"award-number":["12272100","11862003","81860635","12062005"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Guangxi \u201cBagui Scholar\u201d Teams for Innovation and Research Project","award":["12272100","11862003","81860635","12062005"],"award-info":[{"award-number":["12272100","11862003","81860635","12062005"]}]},{"name":"Guangxi Collaborative Innovation Center of Multi-source Information Integration and Intelligent Processing","award":["12272100","11862003","81860635","12062005"],"award-info":[{"award-number":["12272100","11862003","81860635","12062005"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Adjusting the focal length by changing the liquid interface of the liquid lens has become a potential method. In this paper, the lattice-Boltzmann-electrodynamic (LB-ED) method is used to numerically investigate the zooming process of a movable and focus-tunable electrowetting-on-dielectrics (EWOD) liquid lens by combining the LBM chemical potential model and the electrodynamic model. The LB method is used to solve the Navier\u2013Stokes equation, and the Poisson\u2013Boltzmann (PB) equation is introduced to solve the electric field distribution. The experimental results are consistent with the theoretical results of the Lippmann\u2013Young equation. Through the simulation of a liquid lens zoom driven by EWOD, it is found that the lens changes from a convex lens to a concave lens with the voltage increases. The focal length change rate in the convex lens stage gradually increases with voltage. In the concave lens stage, the focal length change rate is opposite to that in the convex lens stage. During the zooming process, the low-viscosity liquid exhibits oscillation, and the high-viscosity liquid appears as overdamping. Additionally, methods were proposed to accelerate lens stabilization at low and high viscosities, achieving speed improvements of about 30% and 50%, respectively. Simulations of lens motion at different viscosities demonstrate that higher-viscosity liquids require higher voltages to achieve the same movement speed.<\/jats:p>","DOI":"10.3390\/e24121714","type":"journal-article","created":{"date-parts":[[2022,11,24]],"date-time":"2022-11-24T03:58:16Z","timestamp":1669262296000},"page":"1714","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Movable and Focus-Tunable Lens Based on Electrically Controllable Liquid: A Lattice Boltzmann Study"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6839-6318","authenticated-orcid":false,"given":"Fei","family":"Wang","sequence":"first","affiliation":[{"name":"Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China"},{"name":"School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9949-7616","authenticated-orcid":false,"given":"Zijian","family":"Zhuang","sequence":"additional","affiliation":[{"name":"Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China"},{"name":"School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3119-5413","authenticated-orcid":false,"given":"Zhangrong","family":"Qin","sequence":"additional","affiliation":[{"name":"Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China"},{"name":"School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0127-3268","authenticated-orcid":false,"given":"Binghai","family":"Wen","sequence":"additional","affiliation":[{"name":"Guangxi Key Lab of Multi-Source Information Mining & Security, Guangxi Normal University, Guilin 541004, China"},{"name":"School of Computer Science and Engineering, Guangxi Normal University, Guilin 541004, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1128","DOI":"10.1063\/1.1779954","article-title":"Variable-focus liquid lens for miniature cameras","volume":"85","author":"Kuiper","year":"2004","journal-title":"Appl. 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