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Related papers: Morphological variations to a ptychographic algori…

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Fourier ptychography is a new computational microscopy technique that provides gigapixel-scale intensity and phase images with both wide field-of-view and high resolution. By capturing a stack of low-resolution images under different…

Fourier Ptychographic Microscopy (FPM) is a recent technique to overcome the diffraction limit of a low numerical aperture (NA) objective lens by algorithmic post-processing of several lower resolved images. It can increase the…

Feature matching is an important technique to identify a single object in different images. It helps machines to construct recognition of a specific object from multiple perspectives. For years, feature matching has been commonly used in…

Computer Vision and Pattern Recognition · Computer Science 2020-10-26 Hang Zhu , Zihao Wang

Ptychography with an unknown mask and object is analyzed for general ptychographic measurement schemes that are strongly connected and possess an anchor. Under a mild constraint on the mask phase, it is proved that the masked object…

Image and Video Processing · Electrical Eng. & Systems 2020-04-13 A. Fannjiang , P. Chen

Fourier ptychographic microscopy (FPM) is a recently developed imaging modality that uses angularly varying illumination to extend a system performance beyond the limit defined by its optical elements. The FPM technique applies a novel…

Optics · Physics 2014-05-02 Xiaoze Ou , Roarke Horstmeyer , Changhuei Yang , Guoan Zheng

A detailed analysis of ptychography for 3D phase reconstructions of thick specimens is performed. We introduce multi-focus ptychography, which incorporates a 4D-STEM defocus series to enhance the quality of 3D reconstructions along the beam…

Ptychography, a special case of the phase retrieval problem, is a popular method in modern imaging. Its measurements are based on the shifts of a locally supported window function. In general, direct recovery of an object from such…

Numerical Analysis · Mathematics 2020-10-28 Anton Forstner , Felix Krahmer , Oleh Melnyk , Nada Sissouno

Ptychography has rapidly grown in the fields of X-ray and electron imaging for its unprecedented ability to achieve nano or atomic scale resolution while simultaneously retrieving chemical or magnetic information from a sample. A…

Image and Video Processing · Electrical Eng. & Systems 2020-04-20 Mathew J. Cherukara , Tao Zhou , Youssef Nashed , Pablo Enfedaque , Alex Hexemer , Ross J. Harder , Martin V. Holt

We consider the problem of blind ptychography, that is the joint estimation of an unknown object and an illumination function from diffraction intensity measurements. In ptychography, diffraction measurements from neighboring regions of the…

Optimization and Control · Mathematics 2016-02-04 Stefano Marchesini , Hau-Tieng Wu

X-ray ptychography is a data-intensive imaging technique expected to become ubiquitous at next-generation light sources delivering many-fold increases in coherent flux. The need for real-time feedback under accelerated acquisition rates…

X-ray ptychography allows for large fields to be imaged at high resolution at the cost of additional computational expense due to the large volume of data. Given limited information regarding the object, the acquired data often has an…

Image and Video Processing · Electrical Eng. & Systems 2022-07-01 Dergan Lin , Yi Jiang , Junjing Deng , Zichao Wendy Di

In this work, we propose using camera arrays coupled with coherent illumination as an effective method of improving spatial resolution in long distance images by a factor of ten and beyond. Recent advances in ptychography have demonstrated…

Computer Vision and Pattern Recognition · Computer Science 2015-11-29 Jason Holloway , M. Salman Asif , Manoj Kumar Sharma , Nathan Matsuda , Roarke Horstmeyer , Oliver Cossairt , Ashok Veeraraghavan

Shape inference is classically ill-posed, because it involves a map from the (2D) image domain to the (3D) world. Standard approaches regularize this problem by either assuming a prior on lighting and rendering or restricting the domain,…

Computer Vision and Pattern Recognition · Computer Science 2020-08-21 Steven W Zucker

The concept of illumination bodies studied in convex geometry is used to amend the halfspace depth for multivariate data. The proposed notion of illumination enables finer resolution of the sample points, naturally breaks ties in the…

Statistics Theory · Mathematics 2021-05-28 Stanislav Nagy , Jiří Dvořák

The availability of affordable and portable depth sensors has made scanning objects and people simpler than ever. However, dealing with occlusions and missing parts is still a significant challenge. The problem of reconstructing a (possibly…

Computer Vision and Pattern Recognition · Computer Science 2018-04-05 Or Litany , Alex Bronstein , Michael Bronstein , Ameesh Makadia

Fourier ptychographic microscopy enables gigapixel-scale imaging, with both large field-of-view and high resolution. Using a set of low-resolution images that are recorded under varying illumination angles, the goal is to computationally…

Signal Processing · Electrical Eng. & Systems 2018-03-13 Emrah Bostan , Mahdi Soltanolkotabi , David Ren , Laura Waller

A solution to the inversion problem of scattering would offer aberration-free diffraction-limited 3D images without the resolution and depth-of-field limitations of lens-based tomographic systems. Powerful algorithms are increasingly being…

We propose a general alternating minimization algorithm for nonconvex optimization problems with separable structure and nonconvex coupling between blocks of variables. To fix our ideas, we apply the methodology to the problem of blind…

Optimization and Control · Mathematics 2018-02-07 Robert Hesse , D. Russell Luke , Shoham Sabach , Matthew K. Tam

Fourier Ptychography (FP) is a recently proposed technique for large field of view and high resolution imaging. Specifically, FP captures a set of low resolution images under angularly varying illuminations and stitches them together in…

Optics · Physics 2014-11-25 Liheng Bian , Jinli Suo , Guohai Situ , Guoan Zheng , Feng Chen , Qionghai Dai

Polarized X-rays allow for imaging birefringent or dichroic properties of materials with nanometric resolution. To disentangle these properties from the electronic density, either a polarization analyzer or several measurements with…