论文标题
PSF - NET:基于地面光学望远镜的非参数点扩展功能模型
PSF--NET: A Non-parametric Point Spread Function Model for Ground Based Optical Telescopes
论文作者
论文摘要
地面光学望远镜受到大气湍流诱导的畸变的严重影响。了解这些像差的特性对于工具设计和图像恢复方法的开发都很重要。由于点扩展函数可以反映整个光学系统的性能,因此使用点扩散函数描述大气湍流引起的畸变是适当的。假设由具有相同轮廓的大气湍流引起的点扩散函数属于同一歧管空间,我们提出了一个非参数点扩散函数-psf-net。 PSF-NET具有循环卷积神经网络结构,是具有相同曲线的大气湍流引起的PSF的歧管空间的统计表示。通过模拟和真实的观察数据测试PSF-NET,我们发现训练有素的PSF-NET可以恢复任何因大气湍流而模糊的短曝光图像,并具有相同的轮廓。此外,我们进一步使用PSF-NET的脉冲响应(可以看作是统计平均PSF)来分析PSF-NET的解释属性。我们发现,统计平均PSF的变化是由大气湍流曲线的变化引起的:随着大气湍流谱的差异的增加,统计平均PSF之间的差异也会增加。本文提出的PSF-NET提供了一种分析大气湍流引起的畸变的新方法,这是为基于地面光学望远镜开发新的观察方法的好处。
Ground based optical telescopes are seriously affected by atmospheric turbulence induced aberrations. Understanding properties of these aberrations is important both for instruments design and image restoration methods development. Because the point spread function can reflect performance of the whole optic system, it is appropriate to use the point spread function to describe atmospheric turbulence induced aberrations. Assuming point spread functions induced by the atmospheric turbulence with the same profile belong to the same manifold space, we propose a non-parametric point spread function -- PSF-NET. The PSF-NET has a cycle convolutional neural network structure and is a statistical representation of the manifold space of PSFs induced by the atmospheric turbulence with the same profile. Testing the PSF-NET with simulated and real observation data, we find that a well trained PSF--NET can restore any short exposure images blurred by atmospheric turbulence with the same profile. Besides, we further use the impulse response of the PSF-NET, which can be viewed as the statistical mean PSF, to analyze interpretation properties of the PSF-NET. We find that variations of statistical mean PSFs are caused by variations of the atmospheric turbulence profile: as the difference of the atmospheric turbulence profile increases, the difference between statistical mean PSFs also increases. The PSF-NET proposed in this paper provides a new way to analyze atmospheric turbulence induced aberrations, which would be benefit to develop new observation methods for ground based optical telescopes.