论文标题
超分辨率波前重建
Super-resolution wavefront reconstruction
论文作者
论文摘要
超分辨率(SR)是一种旨在提高一组测量信号的分辨率的技术。 SR通过组合多个低分辨率采样数据集来检索高频信号含量。 SR在时间和空间域中都是众所周知的。它被广泛用于成像中,以减少和混叠和增强粗略采样图像的分辨率。该论文将SR技术应用于双维波前重建。特别是,我们展示了SR本质上适合于断层造影多波前传感器(WFS)AO系统,以最少的设计工作揭示其许多优势。本文提供了波前传感操作的直接空间和傅立叶 - 启示描述,并演示了如何通过信号重建来利用SR,尤其是在周期性不均匀采样的框架中。研究了元均匀和非均匀的采样方案。然后,提供了SHACK HARTMANN(SH)WFS的SR BI维模型,并分析了灵敏度函数的特征。 SR概念最终通过代表性多WFS SH AO系统的数值模拟进行了验证。我们的结果表明,在SR框架中将几个WFS样本组合到比单个WFS提供的本机框架中授予更多模式的访问权限,并且尽管样品中固定的子孔径大小固定。此外,我们表明,在SR下,相关的噪声传播不会降解。最后,该概念扩展到由单个金字塔WFS产生的信号。总之,应用于波前重建的SR提供了一个新的参数空间,可以将其与所需的波前采样分辨率分解为子量的大小。通过用旧的假设进行缩短,现在可以实现新的,更灵活,更具性能的AO设计。
Super-Resolution (SR) is a technique that seeks to upscale the resolution of a set of measured signals. SR retrieves higher-frequency signal content by combining multiple lower resolution sampled data sets. SR is well known both in the temporal and spatial domains. It is widely used in imaging to reduce aliasing and enhance the resolution of coarsely sampled images.This paper applies the SR technique to the bi-dimensional wavefront reconstruction. In particular, we show how SR is intrinsically suited for tomographic multi WaveFront Sensor (WFS) AO systems revealing many of its advantages with minimal design effort. This paper provides a direct space and Fourier-optics description of the wavefront sensing operation and demonstrate how SR can be exploited through signal reconstruction, especially in the framework of Periodic Nonuniform Sampling. Both meta uniform and nonuniform sampling schemes are investigated. Then, the SR bi-dimensional model for a Shack Hartmann (SH) WFS is provided and the characteristics of the sensitivity function are analyzed. The SR concept is finally validated with numerical simulations of representative multi WFS SH AO systems. Our results show that combining several WFS samples in a SR framework grants access to a larger number of modes than the native one offered by a single WFS and that despite the fixed sub-aperture size across samples. Furthermore, we show that the associated noise propagation is not degraded under SR. Finally, the concept is extended to the signal produced by single Pyramid WFS. In conclusion, SR applied to wavefront reconstruction offers a new parameter space to explore as it decouples the size of the subaperture from the desired wavefront sampling resolution. By cutting short with old assumptions, new, more flexible and better performing AO designs become now possible.