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Vast tunable optical components are realized based on dynamic reconfigurations of the incident wavefronts, such as beam steering and tunable lens. However, the dominant paradigm of current wavefront reconfiguration technologies relies on…

Optics · Physics 2022-01-27 Wenjun Deng , Weiming Zhu , Yuzhi Shi , Zhijun Liu , Guanxing Zang , Jin Qin , Shiyu Zhu

In this paper, we propose a new technique for two-dimensional phase unwrapping. The unwrapped phase is found as the solution of an inverse problem that consists in the minimization of an energy functional. The latter includes a weighted…

PHASECam is the Large Binocular Telescope Interferometer's (LBTI) phase sensor, a near-infrared camera which is used to measure tip/tilt and phase variations between the two AO-corrected apertures of the Large Binocular Telescope (LBT).…

Instrumentation and Methods for Astrophysics · Physics 2018-07-16 E. R. Maier , P. M. Hinz , D. Defrère , S. Ertel , E. Downey

Wavefront shaping (WFS) has emerged as powerful tool to control the propagation of diverse wave phenomena (light, sound, microwaves, ...) in disordered matter for applications including imaging, communication, energy transfer,…

Applied Physics · Physics 2021-05-14 Philipp del Hougne , K. Brahima Yeo , Philippe Besnier , Matthieu Davy

The multi-frequency temporal phase unwrapping (MF-TPU) method, as a classical phase unwrapping algorithm for fringe projection profilometry (FPP), is capable of eliminating the phase ambiguities even in the presence of surface…

Image and Video Processing · Electrical Eng. & Systems 2019-03-29 Wei Yin , Qian Chen , Shijie Feng , Tianyang Tao , Lei Huang , Maciej Trusiak , Anand Asundi , Chao Zuo

This paper introduces a two-and multi-level phase mask design for improved depth of focus. A novel technique is proposed incorporating cubic and generalized cubic wavefront coding (WFC). The obtained system is optical-electronic requiring…

Optics · Physics 2017-07-26 Vladimir Katkovnik , Nicholas Hogasten , Karen Egiazarian

Plasmonic metasurfaces are able to modify the wavefront by altering the light intensity, phase and polarization state. Active plasmonic metasurfaces would allow dynamic modulation of the wavefront which give rise to interesting application…

Reaching the high angular resolution and contrast level desired for exoplanetary science requires us to equip large telescopes with extreme adaptive optics (XAO) systems to compensate for the effect of the atmospheric turbulence at a very…

Instrumentation and Methods for Astrophysics · Physics 2025-11-20 A. Striffling , C. -T. Héritier , R. J. -L Fétick , O. Fauvarque , J. -F Sauvage , A. Carlotti , B. Neichel T. Fusco

There are different techniques to sense the wavefront phase-distortions due to atmospheric turbulence. Curvature sensors are practical in their sensitivity being adjustable to the prevailing atmospheric conditions. Even at the best sites,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Aglae Kellerer , Mark Chun , Christ Ftaclas

Free-space optical communications with moving targets, such as satellite terminals, demand ultrafast wavefront sensing and correction. This is typically addressed using a Shack-Hartmann sensor, which pairs a high-speed camera with a lenslet…

Adaptive optics (AO) is a powerful tool to increase the imaging depth of multiphoton scanning microscopes. For highly scattering tissues, sensorless wavefront correction techniques exhibit robust performance and present a straight-forward…

In this paper we introduce an efficient method to unwrap multi-frequency phase estimates for time-of-flight ranging. The algorithm generates multiple depth hypotheses and uses a spatial kernel density estimate (KDE) to rank them. The…

Computer Vision and Pattern Recognition · Computer Science 2016-08-19 Felix Järemo Lawin , Per-Erik Forssén , Hannes Ovrén

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

With the Extremely Large Telescope-generation telescopes come new challenges. The complexity of these telescopes' pupil creates new problems for Adaptive Optics. In particular, the large spiders necessary to support the massive optics of…

While characterization of coherent wavefields is essential to laser, x-ray and electron imaging, sensors measure the squared magnitude of the field, rather than the field itself. Holography or phase retrieval must be used to characterize…

Image and Video Processing · Electrical Eng. & Systems 2020-12-10 David J. Brady , Timothy J. Schulz , Chengyu Wang

Laser guide star (LGS) wave-front sensing (LGSWFS) is a key element of tomographic adaptive optics system. However, when considering Extremely Large Telescope (ELT) scales, the LGS spot elongation becomes so large that it challenges the…

Images obtained by microscopes are generally degraded by aberrations. Adaptive optics (AO) has been widely used in to compensate for aberrations and improve reduced image quality. Requiring no separate wavefront sensor, sensorless AO…

Optics · Physics 2025-09-23 Biwei Zhang , Qi Hu , Jingyu Wang , Martin J. Booth

Super-resolution (SR) refers to a combination of optical design and signal processing techniques jointly employed to obtain reconstructed wave-fronts at a higher-resolution from multiple low-resolution samples, overcoming the intrinsic…

Instrumentation and Methods for Astrophysics · Physics 2025-12-22 Carlos M. Correia , Charlotte Z. Bond , João Aveiro , François Leroux , Cédric Taïssir Heritier , Christophe Vérinaud

High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky…

Instrumentation and Methods for Astrophysics · Physics 2021-07-19 Steven P. Bos , Michael Bottom , Sam Ragland , Jacques-Robert Delorme , Sylvain Cetre , Laurent Pueyo

The performance of high-contrast imaging instruments is limited by wavefront errors, in particular by non-common path aberrations (NCPAs). Focal-plane wavefront sensing (FPWFS) is appropriate to handle NCPAs because it measures the…

Instrumentation and Methods for Astrophysics · Physics 2022-12-19 M. Quesnel , G. Orban de Xivry , G. Louppe , O. Absil
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