基于压电驱动的变焦距液体透镜的研究

发布时间：2018-10-17 13:49

【摘要】：随着现代光学与微机电系统(MEMS)的发展,精密光学制造与现代工业设备等对变焦距透镜的精密性和成像质量的要求越来越高,这对传统机械系统变焦透镜提出了非常苛刻的要求,微光学液体透镜的提出正是为解决变焦透镜目前存在的问题,于近年中发展起来的小型化、微型化变焦距透镜。它采用液体作为光学介质,利用微流体技术控制并改变液体几何形状或折射率从而实现变焦的目的。之前学者研究的液体透镜大多采用去离子水或无机盐的水溶液作为液体材料。但是水易挥发,自然条件下热稳定性较差,液态温度范围较窄,因此急需寻找能克服上述问题的新型液体透光煤质。作为新型的绿色环保材料,离子液体与其他易挥发的有机溶剂相比,具有不可燃、热容率大、热稳定性好、液态范围宽、离子的电导率高、电化学窗口宽、性质稳定、蒸汽压小,无毒环保等特点。本文的研究主要从以下几个方面着手:1.本文使用离子液体作为液体透镜媒质,探讨离子液体的接触角随液体体积变化的规律,揭示离子液体的用量、透镜尺寸、绝缘层厚度等因素对离子液体变焦透镜的影响。对不同密度及表面张力的离子液体与离子液体和介质层接触过程中接触角随时间变化的关系进行探究。探究离子液体表面张力、离子液体的种类及离子液体的用量对液体变焦透镜的影响。通过与去离子水的表面张力的对比实验的分析,为离子液体在液体变焦透镜的应用及液体透镜性能优化等方面提供依据。2.对比常用液体透镜驱动方式及其机械结构,为使透镜具有较小体积,较宽工作温度范围,较大变焦范围,提出了一种新型单振子压电驱动离子液体变焦透镜。利用有限元仿真软件(FEM)对液体透镜进行了静力学和模态分析。对单振子液体透镜的谐振频率,振动位移等进行了试验研究。研究表明该单振子透镜工作在谐振状态时振动能量最大,有利于较大曲率半径的形成。根据压电振动理论对不同结构透镜的振动模态及频率响应进行分析。3.在新型压电驱动单振子离子液体变焦透镜的基础上,为得到更大振动位移,依据换能器的原理,将单振子液体透镜改为复合换能器系统液体透镜,运用压电效应基本理论及压电陶瓷的振动理论设计三种具有压电超声换能器结构的夹心式换能器振子。并利用有限元软件(FEM)对所设计的结构进行仿真分析,研究不同尺寸透镜振子与振动系统谐振频率的关系,探讨相应变化规律。使用离子液体作为液体透镜透光介质能够有效的克服液体挥发的问题,并且能够适应更宽的温度范围。通过与传统的去离子水进行比较,说明其在高温等极端环境中使用时的优势。由于不同极化方向压电陶瓷的振动形变的方向和大小不同,探讨压电驱动式液体变焦透镜的材料,结构及其尺寸参数等对变焦距液体透镜的影响。针对液体变焦透镜的实际应用,为可用于较低及较高温度等极端条件的液体透镜提供解决方案。上述设计研究所获得的规律和测试结果对于超声技术在液体变焦透镜方面的应用提供一定的理论依据和参考价值。
[Abstract]:With the development of modern optics and micro-electro-mechanical system (MEMS), precision optical manufacturing and modern industrial equipment have become more and more demanding for the precision and imaging quality of zoom lens, this has put forward very strict requirements on the traditional mechanical system zoom lens, In order to solve the problems existing in the zoom lens, the micro-optical liquid lens is a miniaturized and miniaturized focal length lens which has been developed in recent years. it uses liquid as an optical medium to control and change the liquid geometry or index of refraction using micro-fluidic technology to achieve the purpose of zooming. Most of the liquid lenses studied by previous scholars adopt water solution of deionized water or inorganic salt as liquid material. but the water is volatile, the thermal stability is poor under natural conditions, the liquid temperature range is narrow, and therefore, the novel liquid light-transmitting coal quality capable of overcoming the problems is urgently needed. Compared with other volatile organic solvents, the ionic liquid has the characteristics of non-combustible, high heat capacity, good thermal stability, wide liquid range, high ionic conductivity, wide electrochemical window, stable property, small vapor pressure, no toxicity, environmental protection and the like. This paper mainly focuses on the following aspects: 1. In this paper, ionic liquid is used as the medium of liquid lens, and the influence of ionic liquid's contact angle with the change of liquid volume is discussed, and the influence of ionic liquid dosage, lens size and thickness of insulating layer on the ionic liquid zoom lens is revealed. The contact angle of ionic liquid with different density and surface tension and the contact angle of ionic liquid and dielectric layer changes with time. The influence of ionic liquid surface tension, ionic liquid type and ionic liquid on the liquid zoom lens is investigated. Through the analysis of the comparison experiment with the surface tension of deionized water, it provides the basis for the application of ionic liquid in liquid zoom lens and the optimization of liquid lens performance. In order to make the lens have smaller volume, wide operating temperature range and large zoom range, a novel single-vibrator piezoelectric driven ion liquid zoom lens is proposed. The finite element simulation software (FEM) was used to statics and modal analysis of the liquid lens. The resonant frequency and vibration displacement of single-vibrator liquid lens were studied. The results show that the vibration energy is maximized when the single-vibrator lens works in the resonant state, which is beneficial to the formation of larger radius of curvature. Based on the theory of piezoelectric vibration, the vibration modes and frequency response of different structural lenses are analyzed. on the basis of the novel piezoelectric driving single-vibrator ion liquid zoom lens, the single-vibrator liquid lens is changed into a liquid lens of a composite transducer system according to the principle of the transducer, Three sandwich transducer elements with piezoelectric ultrasonic transducer structure are designed by using the basic theory of piezoelectric effect and the vibration theory of piezoelectric ceramics. Finite element software (FEM) is used to analyze the designed structure, and the relationship between lens vibrator and resonant frequency of vibration system is studied. The use of ionic liquid as a liquid lens light-transmitting medium can effectively overcome the problem of liquid volatilization and can adapt to a wider temperature range. The advantage of its use in extreme environments such as high temperatures is illustrated by comparison with conventional de-ionized water. Due to the different directions and sizes of piezoelectric ceramics in different polarization directions, the influence of material, structure and size parameters of piezoelectric driven liquid zoom lens on variable focal length liquid lens is discussed. For practical applications of liquid zoom lenses, solutions are provided for liquid lenses that can be used for extreme conditions such as lower and higher temperatures. The rules and test results obtained by the above design institute provide some theoretical basis and reference value for the application of ultrasonic technology in liquid zoom lens.
【学位授予单位】：苏州科技学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TH74

【相似文献】