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Related papers: A First-Principle Approach to X-ray Active Optics:…

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Realistic simulations of experiments at large scale photon facilities, such as optical laser laboratories, synchrotrons, and free electron lasers, are of vital importance for the successful preparation, execution, and analysis of these…

We present a concept of the X-ray imaging system with high angular-resolution and moderate sensitivity. In this concept, a two-dimensional detector, i.e., imager, is put at a slightly out-of-focused position of the focusing mirror, rather…

Instrumentation and Methods for Astrophysics · Physics 2019-10-23 Yoshitomo Maeda , Ryo Iizuka , Takayuki Hayashi , Toshiki Sato , Nozomi Nakaniwa , Mai Takeo , Hitomi Suzuki , Manabu Ishida , Shiro Ikeda , Mikio Morii

We use Machine Learning (ML) and system identification validation approaches to estimate neural network models of large-scale Deformable Mirrors (DMs) used in Adaptive Optics (AO) systems. To obtain the training, validation, and test data…

Systems and Control · Electrical Eng. & Systems 2019-11-19 Aleksandar Haber

The imaging performance and sensitivity of an X-ray telescope when observing astrophysical sources are primarily governed by the optical design, geometrical uncertainties (figure errors, surface roughness, and mirror alignment…

Instrumentation and Methods for Astrophysics · Physics 2024-05-13 Neeraj K. Tiwari , Santosh V. Vadawale , N. P. S. Mithun , C. S. Vaishnava , Bharath Saiguhan

Variable curvature mirrors of large amplitude are designed by using finite element analysis. The specific case studied reaches at least a 800 {\mu}m sag with an optical quality better than {\lambda}/5 over a 120 mm clear aperture. We…

Instrumentation and Methods for Astrophysics · Physics 2014-11-19 Emmanuel Hugot , Marc Ferrari , Gerard R. Lemaitre , Fabrice Madec , Sebastien Vives , Elodie Chardin , David Le Mignant , Jean Gabriel Cuby

Relying on atomic scattering factors from evaluated databases, a new model for the reflectivity of x rays on solid surfaces has been developed for FLUKA v4-6.0. This model accounts for the variation of reflectivity as a function of the…

Modulation-based imaging (MoBI) is an X-ray phase-contrast technique that uses an intensity modulator (or membrane) in the beam. Although MoBI can be performed in a single shot, multiple exposures are typically needed to improve the quality…

A transformation optics approach was used to derive a general method for designing electromagnetic devices able to manipulate the wave vectors in the specific manner required by the functionality of the device. While the wave paths inside…

Optics · Physics 2017-07-19 Mircea Giloan

Diffraction limited resolution adaptive optics (AO) correction in visible wavelengths requires a high performance control. In this paper we investigate infinite impulse response filters that optimize the wavefront correction: we tested…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 G. Agapito , C. Arcidiacono , F. Quirós-Pacheco , A. Puglisi , S. Esposito

We present an approach to approximating static properties of glasses without experimental inputs rooted in the first-principles random structure sampling. In our approach, the glassy system is represented by a collection (composite) of…

Materials Science · Physics 2025-10-02 Laszlo Wolf , Andrew Novick , Vladan Stevanović

We introduce a conceptual framework for a lensless imaging system which employs an active metasurface as a high-frequency, continuously tunable amplitude and phase modulation aperture, coupled to a discrete single-pixel detector. Using an…

Optics · Physics 2024-11-14 Julie Belleville , Prachi Thureja , Harry A. Atwater

The atomic-level structure of bulk metallic glasses is a key determinant of their properties. An accurate representation of amorphous systems in computational studies has traditionally required large supercells that are unfortunately…

Materials Science · Physics 2024-01-17 Siya Zhu , Jan Schroers , Stefano Curtarolo , Hagen Eckert , Axel van de Walle

X-ray microtomography at synchrotron sources is fundamentally limited by the high radiation dose applied to the samples, which restricts investigations to non-native tissue states and thereby compromises the biological relevance of the…

We introduce an "objective-first" strategy for designing nanophotonic devices, and we demonstrate the design of nanophotonic coupler, cloak, and mimic devices.

Mathematical Physics · Physics 2012-07-12 Jesse Lu , Jelena Vuckovic

Quantitative and analytical analysis of modulation process of the collimator is a great challenge, and is also of great value to the design and development of Fourier transform imaging telescopes. The Hard X-ray Imager (HXI), as one of the…

Instrumentation and Methods for Astrophysics · Physics 2023-02-01 Xian-Kai Jiang , Jian Wu , Deng-Yi Chen , Yi-Ming Hu , Hao-Xiang Wang , Wei Liu , Zhe Zhang

Ptychography has become prominent at synchrotron facilities worldwide for characterizing biological and material specimens' topological structures and properties at the nanometer or atomic scale, due to its lens - less, highly quantitative…

Image and Video Processing · Electrical Eng. & Systems 2025-01-28 Tao Liu , Bingyang Wang , JiangTao Zhao , Maik Kahnt , Fucai Zhang

Adaptive optics normally concerns the feedback correction of phase aberrations. Such correction has been of benefit in various optical systems, with applications ranging in scale from astronomical telescopes to super-resolution microscopes.…

Optics · Physics 2021-10-07 Chao He , Jacopo Antonello , Martin J. Booth

Spatial light modulators enable arbitrary control of the intensity of optical light fields and facilitate a variety of applications in biology, astronomy and atomic, molecular and optical physics. For coherent light fields, holography,…

The theory of specular X-ray reflectivity from a rough interface based upon the reflection function method (RFM) is proposed. The RFM transforms the second order differential equation for the wave amplitude into the non-linear first order…

Materials Science · Physics 2007-05-23 N. V. Bagrets , E. A. Kravtsov , V. V. Ustinov

Optical systems are becoming increasingly important by resolving many bottlenecks in today's communication, electronics, and biomedical systems. However, given the continuous nature of optics, the inability to efficiently analyze optical…

Logic in Computer Science · Computer Science 2014-03-13 Sanaz Khan-Afshar , Umair Siddique , Mohamed Yousri Mahmoud , Vincent Aravantinos , Ons Seddiki , Osman Hasan , Sofiene Tahar
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