论文标题
基于可变厚度结构的结构镜头
Structural Lens Based on Variable Thickness Structures
论文作者
论文摘要
在本文中，我们报告了基于同心圆形结构的镜头设计，其连续更改薄板结构中定义的厚度，以将平面波聚焦为三个斑点（三重焦点），并将从点源散发到三个准确的光束中的三个准直方向（三个光束旋转）的弹性波。受到光学级指数三重聚焦镜头原理的启发，获得了实现此类结构镜头所需的梯度折射率谱的管理方程。使用透镜设计实现了折射率轮廓，该镜头设计具有两个不同厚度变化曲线的同心圆形区域，这些区域定义在薄板中。进行了分析，数值和实验研究，以研究可变厚度结构晶状体的功能。结果表明，这项研究中发展的镜头能够对宽带特性进行三重聚焦和三束式分裂。此外，可以通过根据管理方程来更改镜片厚度曲线来设计焦点的位置和焦点的方向。另外，所提出的镜头是微型和简单的设计，它克服了先前三重焦点和束分裂器的局限性。
In this article, we report a lens design based on a concentric circular structure with continuous changing of thickness defined in a thin plate structure for focusing a plane wave into three spots (triple focusing) and for splitting elastic waves emanating from a point source into three collimated beams of different directions (three-beam splitting). Inspired by the principle of optical graded index triple focusing lens, the governing equations of the gradient refractive index profiles necessary for achieving such structural lens were obtained. The refractive index profiles were realized by using a lens design with two concentric circular areas of different thickness variation profiles defined in a thin plate. Analytical, numerical, and experimental studies were conducted to investigate the functionalities of the variable thickness structural lens. The results showed that the lens developed in this study were able to perform triple focusing and three-beam splitting with broadband property. Furthermore, the locations of focal points and directions of collimated beams can be engineered by changing the lens thickness profiles according to the governing equations. In addition, the proposed lens is miniature and simple design, which overcome the limitations of previous triple focusing and beam splitters.
