液体变焦镜头的研究进展

黄翔; 林四英; 谷丹丹; 卜振翔; 易伟劲; 谢培钦; 王凌云

doi:10.3788/CO.20191206.1179

液体变焦镜头的研究进展

doi: 10.3788/CO.20191206.1179

cstr: 32171.14.CO.20191206.1179

1.
厦门大学机电工程系, 福建厦门 361102
2.
厦门大学萨本栋微米纳米科学技术研究院, 福建厦门 361005

基金项目:

福建省卫生教育联合攻关计划 WKJ2016-2-21

详细信息

作者简介:
黄翔(1995—), 男, 浙江安吉人, 硕士研究生, 2017年于厦门理工学院获得学士学位, 主要从事微光学系统和流体喷射方面的研究。E-mail:huangxiang701@163.com

王凌云(1978—), 男, 四川通江人, 副教授, 博士生导师, 2001年、2009年于厦门大学分别获得学士、博士学位(硕博连读), 主要从事微纳传感系统、微光学系统与人工视觉、流体喷射与3D打印等方面的研究。E-mail:wangly@xmu.edu.cn

中图分类号: TH74
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出版历程
- 收稿日期: 2019-01-18
- 修回日期: 2019-03-04
- 刊出日期: 2019-12-01

Review on progress of variable-focus liquid lens

1.
Department of Mechanical and Electrical Engineering, Xiamen University, Xiamen 361102, China
2.
Pen-Tung Sah Institute of Micro-Nano Science and Technology, Xiamen University, Xiamen 361005, China

Funds:

Fujian Health and Education Joint Tackling Plan WKJ2016-2-21

More Information

Corresponding author: WANG Ling-yun, E-mail:wangly@xmu.edu.cn

摘要

摘要: 相比于传统的机械变焦镜头，液体变焦镜头具有体积小、响应快、成本低和集成度高等特点，被广泛应用于图像采集、目标追踪和特征识别等领域。焦距调节方式决定了液体镜头的性能和应用，本文概括了基于液晶材料、介电泳、电化学、电润湿原理的物性控制式变焦镜头和基于静电力、电磁力、压力调节和环境响应的机械驱动式变焦镜头的研究现状，介绍了液体变焦镜头在光流控芯片内的集成应用，并指出当前面临的主要问题和解决方案。最后，对液体变焦镜头的发展前景和研究方向进行了展望和总结。
- 液体镜头 /
- 焦距调节 /
- 物性控制 /
- 机械驱动
Abstract: Compared with the traditional mechanical zoom lens, the variable-focus liquid lens has a smaller lens, faster response time, lower cost and higher integration capabilities. These lenses are widely used in image acquisition, target tracking and feature recognition. The performance and applications of liquid lenses are determined by the focal length adjustment method. This paper summarizes the progress of liquid crystals, dielectrophoresis, electrochemistry, electrowetting principle-based function control variable-focus lenses, electrostatic force, electromagnetic force, pressure regulation, and environmental-response-technology-based mechanical driven variable-focus lenses. The integrated applications of variable-focus liquid lenses in optofluidic chips are introduced. Also, the major obstacles and the settlement are described. Furthermore, the development potential and future research direction of the variable-focus liquid lens are also predicted and summarized.
- liquid lens /
- focus tunable /
- function control /
- mechanical driven

HTML全文

图 1 液体变焦镜头的分类

Figure 1. Classification of liquid variable-focus lenses

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图 2 不同电压下液晶分子取向示意图^[42]

Figure 2. Liquid crystal molecular orientation model at various voltages^[42]

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图 3 电化学活化液体透镜示意图^[29]

Figure 3. Schematic of electrochemically activated liquid lens^[29]

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图 4 基于介电泳力作用的液体变焦镜头结构和器件^[30]

Figure 4. Structure and device of the variable-focus liquid lens based on dielectrophoresis force^[30]

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图 5 电润湿原理及实验^[45]。(a)介质上电润湿原理示意图；(b)加压前后液滴润湿性实验

Figure 5. Principle and experiment of electrowetting^[45]. (a)Schematic diagram of electrowetting-on-dielectric. (b)Wettability test of droplet before and after applying voltage

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图 6 可调电润湿液体镜头结构与实验^[34]。(a)透镜结构；(b)环形光圈模式；(c)中心光圈模式；(d)焦距与电压的关系

Figure 6. Structure and experiment of the switchable electrowetting liquid lens^[34]. (a)Cell structure. (b)Annular aperture mode. (c)Central clear aperture mode. (d)The relations between focal length and applied voltage

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图 7 基于静电吸引的液体变焦镜头^[47]。(a)透镜截面结构；(b)无电压状态；(c)加电压状态

Figure 7. Variable-focus liquid lens by electrostatic attraction^[47]. (a)Cross-sectional structure of the lens. (b)Without an applied voltage. (c)With an applied voltage

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图 8 3种常见的电磁驱动液体镜头结构^[49-51]。(a)基于电磁吸引的液体变焦镜头；(b)基于通电线圈洛伦兹力驱动的液体变焦镜头；(c)基于铁磁流体流动的液体变焦镜头

Figure 8. Structure of three common electromagnetically driven liquid lenses^[49-51]. (a) Electromagnetic attraction varifocal liquid lens. (b) Electric coil Lorentz force driven varifocal liquid lens. (c) Ferrofluid-based fluid varifocal liquid lens

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图 9 压力调节液体镜头结构^[54-56]。(a)基于液压控制的液体变焦镜头；(b)基于手动操纵的液体变焦镜头；(c)基于形状记忆合金变形的液体变焦镜头

Figure 9. Structures of pressure adjusted liquid lenses^[54-56].(a)Variable-focus liquid lens based on hydraulic control.(b)Variable-focus liquid lens based on manual actuation. (c)Variable-focus liquid lens based on shape memory alloy deformation

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图 10 激光诱导变焦透镜的原理及实验^[59]

Figure 10. Principle and experiment of varifocal liquid lens actuated by laser-induced^[59]

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图 11 超声压电激励液晶透镜^[60]

Figure 11. Liquid crystal lens actuated by ultrasonic piezoelectric ^[60]

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图 12 基于液体变焦镜头集成的光流控芯片^[61-62]。(a)用于流动环境中生物细胞捕捉的热梯度折射率液体镜头；(b)三维液-液双凸凹变焦镜头用于生物细胞成像

Figure 12. Varifocal liquid lens integrated optofluidic chip^[61-62].(a)Thermal gradient refractive index liquid lens for trapping single living cell in flowing environments. (b)Switchable 3D liquid-liquid biconvex lens for biological cell image

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表 1 4种介质层的实验结果

Table 1. Experimental results obtained with four kinds of dielectric layers

介电层	填充液	击穿电压/V	工作电压/V
Parylene C	D.I water	95	10
	SDS	20	2
Parylene C+Al₂O₃	D.I water	125	50
	SDS	22	6
Parylene C+SiO₂	D.I water	120	40
	SDS	20	2
Parylene C+SiO₂+Al₂O₃	D.I water	135	65
	SDS	24	8

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