Clermont L, Uhring W, Georges M
Centre Spatial de Liège, STAR Institute, Université de Liège, Avenue du Pré-Aily, 4031, Liège, Belgium.
ICube Research Institute, University of Strasbourg and CNRS, 23 rue du Loess, 67037, Strasbourg Cedex, France.
Sci Rep. 2021 May 12;11(1):10081. doi: 10.1038/s41598-021-89324-y.
Understanding stray light (SL) is a crucial aspect in the development of high-end optical instruments, for instance space telescopes. As it drives image quality, SL must be controlled by design and characterized experimentally. However, conventional SL characterization methods are limited as they do not provide information on its origins. The problem is complex due to the diversity of light interaction processes with surfaces, creating various SL contributors. Therefore, when SL level is higher than expected, it can be difficult to determine how to improve the system. We demonstrate a new approach, ultrafast time-of-flight SL characterization, where a pulsed laser source and a streak camera are used to record individually SL contributors which travel with a specific optical path length. Furthermore, the optical path length offers a means of identification to determine its origin. We demonstrate this method in an imaging system, measuring and identifying individual ghosts and scattering components. We then show how it can be used to reverse-engineer the instrument SL origins.
了解杂散光（SL）是高端光学仪器（如太空望远镜）开发中的一个关键方面。由于杂散光会影响图像质量，因此必须在设计时对其进行控制，并通过实验进行表征。然而，传统的杂散光表征方法存在局限性，因为它们无法提供有关杂散光来源的信息。由于光与表面相互作用过程的多样性，会产生各种杂散光贡献源，这个问题变得很复杂。因此，当杂散光水平高于预期时，很难确定如何改进系统。我们展示了一种新方法，即超快飞行时间杂散光表征，其中使用脉冲激光源和条纹相机来单独记录以特定光程长度传播的杂散光贡献源。此外，光程长度提供了一种识别手段，以确定其来源。我们在成像系统中演示了这种方法，测量并识别了单个重影和散射成分。然后，我们展示了如何使用它来逆向工程仪器的杂散光来源。
