Individual shape adaptation of microlenses by means of electric fields

微透镜在光学领域有着广泛的应用。因此，允许这种微透镜的个性化形式将是特别有利的。总体而言，3D打印实现了组件的高度个性化。该项目的目的是研究是否有可能在电场的帮助下使3D打印的液体聚合物(=微透镜)变形，然后固化它。这为实现具有自由曲面的微透镜提供了一种新方法。在这个项目中，我们对电场分布和透镜形状之间的关系，以及聚合物的材料性质和由此产生的形式之间的关系，达成了基本的理解。还有必要研究光学特性如何与可实现的形状和材料特性相关。这个项目的总体目标是从不同的角度来研究这个主题，即通过实验和模拟模型来考虑光学属性、3D打印、电场和材料属性的相互作用，以获得全面、更深入的理解。具体而言，应实现以下目标：研究不同电场分布(不同强度)对印刷液体聚合物液滴(针对不同材料、基材和印刷体积)变形的影响。在这里，材料参数，如极化率、粘度、固化过程中的收缩或主题，如基材和液滴之间的相互作用，起着重要的作用。为了把握这些关系，加深理解，有必要在MatLab和Ansys中建立相应的仿真模型，并在实验的基础上进行验证。在这样做的过程中，关键是要将材料方面与电场所产生的变形联系起来，这最终决定了微透镜的光学性能。一方面，需要对衬底进行预结构化，以便为液滴的形成和变形提供进一步的边界条件。另一方面，应例如通过驻留表面波来产生限定的对称表面结构，因为这将是许多光学应用所期望的。再次，将光学、电场和材料方面的相互作用结合起来，并从整体上加以考虑。最后，实现并详细研究了基于多个透镜的微透镜系统。除了系统的光学性能问题外，还有WRT问题。材料科学(扩散、裂纹等)也需要寻址，例如在两个微透镜元件之间的边界层处。

Microlenses show a wide application in optics. Thereby it would be especially of advantage to allow an individualized form of such microlenses. In general, 3D printing enables a high level of individualization of components.The aim of this project is to investigate whether it is possible to deform a 3D printed liquid polymer (=microlens) with the help of electric fields and then cure it. This allows a new way to realize microlenses with free-form surfaces. A basic understanding, e.g. with regard to the relationship between the distribution of the electric fields and the lens shape, as well as with respect to the material properties of the polymers and the resulting forms are worked out in this project. It is also necessary to investigate how the optical properties relate to the realizable shape and the material properties. The general aim of this project is to examine the topic from different perspectives, i.e. to consider the interplay of optical properties, 3D printing, electrical fields and material properties experimentally and via simulation models in order to gain a holistic, deeper understanding. In detail, the following goals should be achieved:The influence of different electric field distributions (at different intensities) on the deformation of the printed liquid polymer droplets (for different materials, substrates and print volumes) has to be investigated. Here, material parameters such as polarizability, viscosity, shrinkage during curing or topics such as the interaction between substrate and droplets play an important role. In order to grasp these relationships and to gain a deeper understanding, it is necessary to build up corresponding simulation models in Matlab and ANSYS and to validate them on the basis of experiments. In doing so, it is crucial to correlate the material aspects with the deformations achieved by the electric fields, which ultimately determines the optical performance of the microlens.The above-mentioned examinations should then be expanded. On the one hand, a pre-structuring of the substrates needs to be carried out in order to enable further boundary conditions for the formation of droplets and deformation. On the other hand, a defined symmetrical surface structure should be generated, e.g. by standing surface waves, as this would be desirable for many optical applications. Once again, it is important to combine the interplay of optics, electrical fields and material aspects with each other and to consider them holistically.Finally, a micro lens system based on several lenses should be realized and studied in detail. In addition to the question of the optical performance of the system, questions wrt. material science (diffusion, cracks, etc.) need to be addressed as well, e.g. at the boundary layer between two microlens elements.