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Laser guide stars (LGSs) have been deployed for the last 20-30 years in ground-based astronomical telescopes to overcome the limited sky coverage of classical adaptive optics (AO) systems. Unfortunately, slow altitude drifts of the sodium…

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang

The concept of Wavelength Frame Multiplication (WFM) was developed to extend the usable wavelength range on long pulse neutron sources for instruments using pulse shaping choppers. For some instruments, it is combined with a pulse shaping…

Instrumentation and Detectors · Physics 2013-07-18 D. Nekrassov , C. Zendler , K. Lieutenant

Photonic lanterns (PLs) are fiber-based waveguides that are capable of focal-plane wavefront sensing while simultaneously directing light to downstream science instruments. The optimal choice of wavefront reconstruction algorithm has yet to…

Pupil mapping is a promising and unconventional new method for high contrast imaging being considered for terrestrial exoplanet searches. It employs two (or more) specially designed aspheric mirrors to create a high-contrast amplitude…

Astrophysics · Physics 2011-02-11 Ruslan Belikov , N. Jeremy Kasdin , Robert J. Vanderbei

Phase imaging techniques extract the optical path-length information of a scene, whereas wavefront sensors provide the shape of an optical wavefront. Since these two applications have different technical requirements, they have developed…

Optics · Physics 2018-02-28 F. Soldevila , V. Durán , P. Clemente , J. Lancis , E. Tajahuerce

It is by now well known that pyramid based wavefront sensors, once in closed loop, have the capability to improve more and more the gain as the reference natural star image size is getting smaller on the pyramid pin. Especially in extreme…

Instrumentation and Methods for Astrophysics · Physics 2018-08-03 D. Magrin , S. Bonora , M. Quintavalla , P. Favazza , M. Bergomi , G. Umbriaco , S. Chinellato , R. Ragazzoni

An adaptive optics system with a single deformable mirror is being implemented on the THEMIS 90cm solar telescope. This system is designed to operate in the visible and is required to be as robust as possible in order to deliver the best…

Instrumentation and Methods for Astrophysics · Physics 2021-01-11 Michel Tallon , Éric Thiébaut , Maud Langlois , Bernard Gelly , Richard Douet , Clémentine Béchet , Loïc Denis , Gil Moretto

Imaging with a layered superlens is a spatial filtering operation characterized by the point spread function (PSF). We show that in the same optical system the image of a narrow sub-wavelength Gaussian incident field may be surprisingly…

Optics · Physics 2010-04-08 Rafal Kotynski , Tomasz Stefaniuk

Advanced wavefront sensors (WFS) are essential for enabling new science cases for telescopes that utilize adaptive optics (AO) systems. While complex field WFS -- those that estimate the electric field phase and amplitude through…

Instrumentation and Methods for Astrophysics · Physics 2025-08-21 D. Angelica Huerta , Justin R. Crepp , Caleb G. Abbott , Brian Joseph

The limits for adaptive-optics (AO) imaging at high contrast and high resolution are determined by residual phase errors from non-common-path aberrations not sensed by the wavefront sensor, especially for integral field spectrographs, where…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Benjamin Pope , Niranjan Thatte , Rick Burruss , Matthias Tecza , Fraser Clarke , Garret Cotter

We consider the mathematical background of the wavefront sensor type that is widely used in Adaptive Optics systems for astronomy, microscopy, and ophthalmology. The theoretical analysis of the pyramid sensor forward operators presented in…

Instrumentation and Methods for Astrophysics · Physics 2019-05-01 Victoria Hutterer , Ronny Ramlau , Iuliia Shatokhina

Most research on astrophysical lensing has been conducted using the geometric optics framework, where there exists a clear concept of lensing images. However, wave optics effects can be important for coherent sources, e.g. pulsars, fast…

Instrumentation and Methods for Astrophysics · Physics 2024-10-29 Xun Shi

Inverse source problems are central to many applications in acoustics, geophysics, non-destructive testing, and more. Traditional imaging methods suffer from the resolution limit, preventing distinction of sources separated by less than the…

Machine Learning · Computer Science 2022-08-11 Adar Kahana , Symeon Papadimitropoulos , Eli Turkel , Dmitry Batenkov

State-of-the-art time-of-flight (ToF) based 3D sensors suffer from poor lateral and depth resolutions. In this work, we introduce a novel sensor concept that provides ToF-based 3D measurements of real world objects with depth precisions up…

Lidar has become a cornerstone sensing modality for 3D vision, especially for large outdoor scenarios and autonomous driving. Conventional lidar sensors are capable of providing centimeter-accurate distance information by emitting laser…

Computer Vision and Pattern Recognition · Computer Science 2024-06-12 Dominik Scheuble , Chenyang Lei , Seung-Hwan Baek , Mario Bijelic , Felix Heide

Wavefront sensing in solar adaptive-optics is currently done with correlating Shack-Hartmann sensors, although the spatial- and temporal-resolutions of the phase measurements are then limited by the extremely fast computing required to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Aglae Kellerer

Focal plane wavefront sensing and control is a critical approach to reducing non-common path errors between the a conventional astronomical adaptive optics (AO) wavefront sensor (WFS) detector and science camera. However, in addition to…

Instrumentation and Methods for Astrophysics · Physics 2023-03-01 Benjamin L. Gerard , Daren Dillon , Sylvain Cetre , Rebecca Jensen-Clem

In this paper the angular characteristics of a multimode fiber SPR sensor are theoretically investigated. By separating the contributions of beams incident at different angles, a compact model is presented to predict the shift of the…

Optics · Physics 2015-11-13 Zhixin Tan , Xin Hao , Xuejin Li , Yuzhi Chen , Xueming Hong , Ping Fan

We introduce in this article a general formalism for Fourier based wave front sensing. To do so, we consider the filtering mask as a free parameter. Such an approach allows to unify sensors like the Pyramid Wave Front Sensor (PWFS) and the…

Instrumentation and Methods for Astrophysics · Physics 2016-12-02 Olivier Fauvarque , Benoit Neichel , Thierry Fusco , Jean-François Sauvage , Orion Girault
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