AI 中文总结
该研究设计了一款7°入射的长通二向色镜，通过多层薄膜与反射相位优化降低像差，模拟显示其不会限制矢量涡旋日冕仪的性能，可用于HWO的高对比度成像
AI 中文摘要
拟议的宜居世界天文台（Habitable Worlds Observatory, HWO）旨在通过高对比度成像，从紫外到红外波段探测和表征类太阳恒星周围的类地行星。在该系统中，二向色镜是分割多个波长通道光的自然选择，但膜层必须引入最小的偏振像差和色差波前误差（Wavefront Error, WFE），以避免限制对比度。我们展示了一款以7°入射角工作的长通二向色镜的设计，其在短波长波段提供高反射，在长波长波段提供高透射，并在550 nm附近具有陡峭的截止边。采用多层薄膜设计工艺来满足这些光谱要求，同时降低偏振像差和色差WFE的敏感性。还纳入了反射相位优化，以降低制造引起的层厚变化的敏感性，这种变化会产生与波长相关的WFE并降低日冕仪性能。通过矢量涡旋日冕仪的模拟，评估了膜层诱导的WFE对对比度性能的影响。模拟预测暗斑对比度残差处于10⁻¹²量级，表明优化后的二向色镜不会限制日冕仪的性能。
英文摘要
The proposed Habitable Worlds Observatory (HWO) aims to detect and characterize Earth-like planets around Sun-like stars from the ultraviolet to the infrared using high-contrast imaging. A dichroic mirror is a natural choice for splitting light between multiple wavelength channels in such a system, but the coating must introduce minimal polarization aberrations and chromatic wavefront errors (WFE) to avoid limiting contrast. We present the design of a long-pass dichroic mirror operated at a $7^\circ$ angle of incidence that provides high reflection in the short-wavelength band, high transmission in the long-wavelength band, and a sharp cut-on near 550~nm. A multilayer thin-film design process was used to meet these spectral requirements while reducing polarization aberrations and chromatic WFE sensitivity. Reflected phase optimization was also incorporated to reduce sensitivity to manufacturing-induced layer-thickness variations, which can produce wavelength-dependent WFE and degrade coronagraph performance. The resulting coating-induced WFE was propagated through simulations of a vector vortex coronagraph to assess contrast performance. Simulations predict dark-hole contrast residuals at the $10^{-12}$ level, indicating that the optimized dichroic mirror does not limit coronagraph performance.
CommentsSPIE Astronomical Telescopes & Instrumentation 2026
