Harness Anthony, Shaklan Stuart, Cash Webster, Dumont Philip
J Opt Soc Am A Opt Image Sci Vis. 2018 Feb 1;35(2):275-285. doi: 10.1364/JOSAA.35.000275.
Starshade external occulters are a leading technology that provide the starlight suppression needed to directly image and spectroscopically characterize Earth-sized exoplanets in the habitable zone of nearby stars. A high-priority technology area identified in need of development for a future starshade mission is the development and validation of high-fidelity optical models to predict the performance of a full-scale starshade. We present the generalization of an algorithm to formulate the Fresnel diffraction equation as a one-dimensional integral around the edge of an arbitrary binary diffraction screen. Our edge integral provides an efficient method for capturing diffraction over a large range of size scales and is computationally superior to standard two-dimensional codes. We also present a novel method to implement wavefront errors with the edge integral. This paper provides the derivation of the algorithms and their validation with comparisons to known solutions and results from standard Fresnel propagation codes.
星芒遮光器是一种前沿技术，它能抑制星光，从而直接对邻近恒星宜居带内的地球大小的系外行星进行成像，并通过光谱对其进行特征描述。未来星芒遮光器任务中确定的一个高优先级技术开发领域是开发和验证高保真光学模型，以预测全尺寸星芒遮光器的性能。我们提出了一种算法的推广形式，将菲涅耳衍射方程表述为围绕任意二元衍射屏边缘的一维积分。我们的边缘积分提供了一种有效的方法来捕捉大范围尺寸尺度上的衍射，并且在计算上优于标准的二维编码。我们还提出了一种用边缘积分实现波前误差的新方法。本文给出了算法的推导过程，并通过与已知解以及标准菲涅耳传播编码的结果进行比较来验证算法。
