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With sub-microarcsecond angular accuracy, the \theia telescope will be capable of revealing the architectures of nearby exoplanetary systems down to the mass of Earth. This research addresses the challenges inherent in space astrometry…

Instrumentation and Methods for Astrophysics · Physics 2024-08-29 F. Malbet , M. Lizzana , F. Pancher , S. Soler , A. Léger , T. Lépine , G. A. Mamon , A. Sozzetti , A. Riva , D. Busonero , L. Labadie , P. -O. Lagage , R. Goullioud

This paper presents a blind detection and compensation technique for camera lens geometric distortions. The lens distortion introduces higher-order correlations in the frequency domain and in turn it can be detected using higher-order…

Computer Vision and Pattern Recognition · Computer Science 2007-05-23 Lili Ma , YangQuan Chen , Kevin L. Moore

Optical aberrations prevent telescopes from reaching their theoretical diffraction limit. Once estimated, these aberrations can be compensated for using deformable mirrors in a closed loop. Focal plane wavefront sensing enables the…

This article presents research work on a spectroscopic survey telescope. Our idea is as follows: for such a telescope, a pure reflecting optical system is designed, which should have an aperture and a field of view (FOV) both as large as…

Instrumentation and Methods for Astrophysics · Physics 2024-03-20 Ding-qiang Su , Hua Bai , Xiangyan Yuan , Xiangqun Cui

A perfect focus telescope is one in which all rays parallel to the axis meet at a point and give equal magnification there. It is shown that these two conditions define the shapes of both primary and secondary mirrors. Apart from scale, the…

Optics · Physics 2009-11-07 D. Lynden-Bell

A compensator (null-corrector) for testing aspheric optical surfaces is proposed, which enables i) independent verification of optical elements and assembling of the compensator itself, and ii) ascertaining the compensator position in a…

Instrumentation and Methods for Astrophysics · Physics 2014-02-26 V. Yu. Terebizh

Vision-based motion estimation and 3D reconstruction, which have numerous applications (e.g., autonomous driving, navigation systems for airborne devices and augmented reality) are receiving significant research attention. To increase the…

Computer Vision and Pattern Recognition · Computer Science 2018-10-30 Vladyslav Usenko , Nikolaus Demmel , Daniel Cremers

In ground based astronomical observations, atmospheric dispersion shifts the image of the object at different wavelengths due to the wavelength-dependent index of refraction of the atmosphere. Thus, using an Atmospheric Dispersion Corrector…

Instrumentation and Methods for Astrophysics · Physics 2019-12-06 Bachar Wehbe , Alexandre Cabral , Gerardo Avila

Ultrathin meta-optics offer unmatched, multifunctional control of light. Next-generation optical technologies, however, demand unprecedented performance. This will likely require design algorithms surpassing the capability of human…

Optics · Physics 2021-04-06 Shane Colburn , Arka Majumdar

Adaptive (or deformable) mirrors are widely used as wavefront correctors in adaptive optics systems. The optical calibration of an adaptive mirror is a fundamental step during its life-cycle: the process is in facts required to compute a…

Instrumentation and Methods for Astrophysics · Physics 2022-10-11 Runa Briguglio , Marco Xompero , Armando Riccardi

As the performance of coronagraphs improves, the achievable contrast is more and more dependent of the shape of the pupil. The future generation of space and ground based coronagraphic instruments will have to achieve high contrast levels…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Johan Mazoyer , Laurent Pueyo , Colin Norman , Mamadou N'Diaye , Dimitri Mawet , Rémi Soummer , Marshall Perrin , Élodie Choquet , Alexis Carlotti

The multi-plane phase retrieval method provides a budget-friendly and effective way to perform phase imaging, yet it often encounters alignment challenges due to shifts along the optical axis in experiments. Traditional methods, such as…

Optics · Physics 2024-05-01 Jiabao Wang , Yang Wu , Jun Wang , Ni Chen

Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

We present two novel designs for a telescope suitable for massively-multiplexed spectroscopy. The first is a very wide field Cassegrain telescope optimised for fibre feeding. It provides a Field Of View (FOV) of 2.5 degrees diameter with a…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 L. Pasquini , B. Delabre , R. Ellis , T. de Zeeuw

Active optics is defined as the control of the shape and the alignment of the components of an optical system at low temporal frequencies. For modern large telescopes with flexible monolithic or segmented primary mirrors and also flexible…

Astrophysics · Physics 2007-05-23 Lothar Noethe

The Astro2020 decadal survey recommended an infrared, optical, ultra-violet (IR/O/UV) telescope with a $\sim$6~m inscribed diameter and equipped with a coronagraph instrument to directly image exoEarths in the habitable zone of their host…

An analytical description of arbitrary strongly aberrated axially symmetric focusing is developed. This is done by matching the solution of geometrical optics with a wave pattern which is universal for the underlying ray structure. The…

Optics · Physics 2007-05-23 Johannes Kofler , Nikita Arnold

We present an inverse method for transforming a given parallel light emittance to two light distributions at different parallel target planes using two freeform reflectors. The reflectors control both the spatial and directional target…

Wide-Field Corrector designs are presented for the Blanco and Mayall telescopes, the CFHT and the AAT. The designs are Terezibh-style, with 5 or 6 lenses, and modest negative optical power. They have 2.2-3 degree fields of view, with curved…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Will Saunders , Peter Gillingham , Greg Smith , Steve Kent , Peter Doel

Accurately calibrating light field camera is essential to its applications. Rapid progress has been made in this area in the past decades. In this paper, detailed analysis was first performed towards the state of the art projection models…

Computer Vision and Pattern Recognition · Computer Science 2021-03-11 Dongyang Jin , Saiping Zhang , Xiao Huo , Wei Zhang , Fuzheng Yang