Meitav Nizan, Ribak Erez N, Shoham Shy
Department of Biomedical Engineering, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel.
Department of Physics, Technion-Israel Institute of Technology, Technion City, Haifa 32000, Israel.
Light Sci Appl. 2016 Mar 25;5(3):e16048. doi: 10.1038/lsa.2016.48. eCollection 2016 Mar.
The resolution of an imaging apparatus is ideally limited by the diffraction properties of the light passing through the system aperture, but in many practical cases, inhomogeneities in the light propagating medium or imperfections in the optics degrade the image resolution. Here we introduce a powerful and practical new approach for estimating the point spread function (PSF) of an imaging system on the basis of PSF Estimation from Projected Speckle Illumination (PEPSI). PEPSI uses the fact that the speckles' phase randomness cancels the effects of the aberrations in the illumination path, thereby providing an objective pattern for measuring the deformation of the imaging path. Using this approach, both wide-field-of-view and local-PSF estimation can be obtained by calibration-free, single-speckle-pattern projection. Finally, we demonstrate the feasibility of using PEPSI estimates for resolution improvement in iterative maximum likelihood deconvolution.
成像设备的分辨率在理想情况下受通过系统孔径的光的衍射特性限制，但在许多实际情况下，光传播介质中的不均匀性或光学元件的缺陷会降低图像分辨率。在此，我们基于投影散斑照明的点扩散函数估计（PEPSI），介绍一种用于估计成像系统点扩散函数（PSF）的强大且实用的新方法。PEPSI利用散斑相位随机性抵消照明路径中像差影响这一事实，从而提供一种用于测量成像路径变形的客观图案。使用这种方法，通过无校准的单散斑图案投影即可获得宽视场和局部PSF估计。最后，我们证明了在迭代最大似然反卷积中使用PEPSI估计来提高分辨率的可行性。
