3D diffractive elements through fs-laser direct writing

飞秒激光直写3D衍射元件

• 批准号: 409765270
• 负责人: Professor Dr.-Ing. Michael Schmidt
• 金额: --
• 依托单位: Lehrstuhl für Photonische Technologien (LPT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/409765270?language=en
• 关键词: 3D; diffractive; elements; through; fs

Diffractive optical elements (DOEs) are powerful tools for shaping light into almost arbitrary patterns. They find increasing use in advanced laser material processing and imaging applications, for instance to parallelize and thus accelerate fabrication steps.DOEs are commonly made by etching micro-meter structures into the surface of a glass blank. However, it is known that they could be even more powerful and versatile if they were three-dimensional, i.e., if the structures were directly written into the bulk of a small glass slab. Such 3D DOEs could exhibit exquisite sensitivity to color and beam incidence angle, thus enabling a new class of optical elements. For instance, they could be made small enough to fit onto a microscopy glass slide and at the same time sufficiently sensitive to differentiate closely resembling cell types, solely from the light they reflect.Current limitations of realizing 3D DOEs of higher complexity are given by the required large computational costs as well as the lack of fabrication strategies that are sufficiently fast and capable of writing sub-micron sized voxels in millimetre depths. Our research aims to take significant steps towards the realization of 3D DOEs. We plan to develop new algorithms for their design as well as a novel fabrication approach which is apt to fulfil the high demands imposed by the fabrication task. Our approach will be based on parallel femtosecond-laser direct writing (FLDW), where many voxels are simultaneously produced by irradiating the material with short-pulsed laser foci. In the course of our project, we will address the design and production of DOEs with increasing difficulty and complexity. In three subsequent stages we will design and produce 2D, multilayer and finally 3D DOEs.

衍射光学元件（DOE）是将光整形成几乎任意图案的强大工具。它们在先进的激光材料加工和成像应用中得到越来越多的应用，例如并行化，从而加速制造步骤。DOE通常通过在玻璃坯件表面蚀刻微米结构来制造。然而，已知的是，如果它们是三维的，即，如果结构被直接写入小玻璃板的块体中。这种3D DOE可以对颜色和光束入射角表现出极高的灵敏度，从而实现一类新的光学元件。例如，它们可以做得足够小，以适合显微镜载玻片，同时足够敏感，以区分密切相似的细胞类型，实现更高复杂度的3D DOE的当前限制是由所需的大计算成本以及缺乏足够快且能够写入亚微米的制造策略给出的。微米大小的体素在毫米深度。我们的研究旨在朝着实现3D DOE迈出重要的一步。我们计划为它们的设计开发新的算法，以及一种新的制造方法，这种方法易于满足制造任务的高要求。我们的方法将基于并行飞秒激光直写（FLDW），其中许多体素同时产生的材料与短脉冲激光焦点照射。 在我们的项目过程中，我们将解决DOE的设计和生产越来越困难和复杂。在随后的三个阶段中，我们将设计和生产2D，多层和最终的3D DOE。