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1. 16W-pulsed green laser based on efficient frequency conversion of an Yb-doped fibre laser externally modulated by a semiconductor optical amplifier

Author

Adil Haboucha, Arnaud Fernandez, Alain Mugnier, Thierry Chartier, Christelle Pareige, David Pureur, Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Centre National de la Recherche Scientifique (CNRS)-Télécom Bretagne, Quantel-Lannion (QSA), Quantel, Fonctions Optiques pour les Technologies de l'informatiON ( FOTON ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Université européenne de Bretagne ( UEB ) -Institut National des Sciences Appliquées - Rennes ( INSA Rennes ), Institut National des Sciences Appliquées ( INSA ) -Université de Rennes ( UNIV-RENNES ) -Institut National des Sciences Appliquées ( INSA ) -École Nationale Supérieure des Sciences Appliquées et de Technologie ( ENSSAT ) -Centre National de la Recherche Scientifique ( CNRS ) -Télécom Bretagne, Quantel-Lannion ( QSA ), Équipe Microondes et Opto-microondes pour Systèmes de Télécommunications ( LAAS-MOST ), Laboratoire d'analyse et d'architecture des systèmes [Toulouse] ( LAAS ), Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse III - Paul Sabatier ( UPS ), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse ( INSA Toulouse ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Institut National Polytechnique [Toulouse] ( INP ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Toulouse III - Paul Sabatier ( UPS ), Institut National des Sciences Appliquées ( INSA ) -Institut National des Sciences Appliquées ( INSA ) -Institut National Polytechnique [Toulouse] ( INP ), Université de Rennes (UR)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS)

Subjects
Optical amplifier, Materials science, business.industry, 02 engineering and technology, Injection seeder, 021001 nanoscience & nanotechnology, Laser, 01 natural sciences, 7. Clean energy, law.invention, 010309 optics, Optics, law, Fiber laser, 0103 physical sciences, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, Semiconductor optical gain, Laser beam quality, Laser power scaling, [ SPI.OPTI ] Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, Tunable laser
Abstract

International audience; We report on the development of a nanosecond green laser based on efficient frequency conversion of an Yb-doped fibre laser externally modulated by a semiconductor optical amplifier. The laser system uses commercially available fibers and operates with pulse durations in the range 3-40 ns and repetition rates in the range 50-800 kHz. A maximum conversion efficiency of 66 % and a maximum average output power of 16 W have been reached for a repetition rate of 250 kHz and a pulse duration of 8 ns while preserving a high beam quality.

Published
2014
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2. Numerical simulation of incoherent optical wave propagation in nonlinear fibres

Author

Stéphane Balac, David Pureur, Arnaud Fernandez, Rozenn Texier-Picard, Fabrice Mahé, Thierry Chartier, Alain Mugnier, Fonctions Optiques pour les Technologies de l'informatiON ( FOTON ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Université européenne de Bretagne ( UEB ) -Institut National des Sciences Appliquées - Rennes ( INSA Rennes ) -École Nationale Supérieure des Sciences Appliquées et de Technologie ( ENSSAT ) -Télécom Bretagne-Centre National de la Recherche Scientifique ( CNRS ), Quantel-Lannion ( QSA ), Quantel, Institut de Recherche Mathématique de Rennes ( IRMAR ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -AGROCAMPUS OUEST-École normale supérieure - Rennes ( ENS Rennes ) -Institut National de Recherche en Informatique et en Automatique ( Inria ) -Institut National des Sciences Appliquées ( INSA ) -Université de Rennes 2 ( UR2 ), Université de Rennes ( UNIV-RENNES ) -Centre National de la Recherche Scientifique ( CNRS ), Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS), Quantel-Lannion (QSA), Institut de Recherche Mathématique de Rennes (IRMAR), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université de Rennes 2 (UR2), Université de Rennes (UNIV-RENNES)-École normale supérieure - Rennes (ENS Rennes)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), Université de Rennes (UR)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École normale supérieure - Rennes (ENS Rennes)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-INSTITUT AGRO Agrocampus Ouest, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Équipe Microondes et Opto-microondes pour Systèmes de Télécommunications (LAAS-MOST), Laboratoire d'analyse et d'architecture des systèmes (LAAS), Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse - Jean Jaurès (UT2J)-Université Toulouse 1 Capitole (UT1), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de Mathématiques Appliquées de Lyon (MAPLY), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Laboratoire de Matériaux Céramiques et Traitements de Surface (LMCTS), Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université Toulouse - Jean Jaurès (UT2J), Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université Toulouse Capitole (UT Capitole), Université de Toulouse (UT), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Photon, Kerr effect, interaction picture method, Wave propagation, Physics::Optics, 02 engineering and technology, 01 natural sciences, law.invention, 010309 optics, symbols.namesake, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Statistical physics, Instrumentation, Nonlinear Schrödinger equation, supercontinuum generation, response function, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Computer simulation, business.industry, Amplifier, Runge-Kutta, [ MATH.MATH-NA ] Mathematics [math]/Numerical Analysis [math.NA], Condensed Matter Physics, Laser, Electronic, Optical and Magnetic Materials, Nonlinear system, symbols, business, [MATH.MATH-NA]Mathematics [math]/Numerical Analysis [math.NA]
Abstract

International audience; The present work concerns the study of pulsed laser systems containing a fibre amplifier for boosting optical output power. In this paper, this fibre amplification device is included into a MOPFA laser, a master oscillator coupled with fibre amplifier, usually a cladding-pumped high-power amplifier often based on an ytterbium-doped fibre. An experimental study has established that the observed nonlinear effects (such as Kerr effect, four waves mixing, Raman effect) could behave very differently depending on the characteristics of the optical source emitted by the master laser. However, it has not been yet possible to determine from the experimental data if the statistics of the photons is alone responsible for the various nonlinear scenarios observed. Therefore, we have developed a numerical simulation software for solving the generalised nonlinear Schrödinger equation with a stochastic source term in order to validate the hypothesis that the coherence properties of the master laser are mainly liable for the behaviour of the observed nonlinear effects.

Published
2013
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3. First demonstration of a 12 DFB fiber laser array on a 100 GHz ITU grid, for underwater acoustic sensing application

Author

Pascal Besnard, Yohann Léguillon, Alain Mugnier, Martine Doisy, K. Hey Tow, David Pureur, Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Centre National de la Recherche Scientifique (CNRS)-Télécom Bretagne, Quantel-Lannion (QSA), Quantel, Thales Underwater Systems, Projet FUI ATOS, Université de Rennes (UR)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS)

Subjects
Materials science, Optical fiber, 02 engineering and technology, 01 natural sciences, Semiconductor laser theory, law.invention, 010309 optics, 020210 optoelectronics & photonics, Optics, acoustic sensors, law, Fiber laser, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Laser diode, business.industry, optical fiber sensors, Distributed feedback fiber laser, Distributed acoustic sensing, Laser, hydrophone, Noise floor, Fiber optic sensor, fiber laser acoustic sensors, business, multiplexed sensing
Abstract

International audience; We report for the first time a multiplexed array of 12 distributed feedback fiber lasers (DFB FLs) on a single optical fiber, separated by only 100 GHz (0.8 nm) in the C-band. These lasers are pumped by a 200 mW laser diode at 1480 nm with no apparent impact on the sensor noise floor despite the fact that the residual reflections from adjacent gratings may be enhanced due to the smaller wavelength separation. Each DFB FL, especially developed for serial multiplexing, exhibits low lasing threshold typically between 1 and 2 mW, low intensity noise and very low frequency noise (less than 30 dB re 1 Hz²/Hz at 1 kHz from optical carrier). From these experimental results, extension to 32 DFB FLs array (on 100 GHz ITU grid) multiplexed on one fiber will be discussed.

Published
2012
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4. 20 ns smooth pulse generation in single mode actively Q-switched double clad Yb-doped fiber laser

Author

Patrick Beaure d'Augères, Thierry Chartier, David Pureur, Alain Mugnier, Quantel-Lannion (QSA), Quantel, Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne

Subjects
Active laser medium, Materials science, business.industry, Single-mode optical fiber, Physics::Optics, Pulse duration, Polarization-maintaining optical fiber, 02 engineering and technology, Injection seeder, 021001 nanoscience & nanotechnology, Laser, 01 natural sciences, Q-switching, law.invention, 010309 optics, Optics, law, Fiber laser, 0103 physical sciences, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business
Abstract

Master Oscillator - Power Fiber Amplifier (MOPFA) configuration is a standard configuration for pulsed fiber laser systems used in material processing applications. To improve the marking process efficiency, it is benefit to increase the output peak power of these lasers, which can be obtained by reducing the oscillator pulse width. Q-switched fiber lasers are a priori good candidates for this purpose. However, in these systems, the longitudinal distribution of the gain medium and the length of fiber components determine a cavity length longer than in bulk lasers. One consequence is strong intensity variations along the fiber which can leads to multipeaks generation [1]. On the other hand, to decrease pulse duration, the pump power must be increased and this leads to detrimental nonlinear effects. To avoid these problems, the power density is usually reduced by using large mode area fibers but with a detrimental effect on the spatial beam quality [2]. In this paper, we theoretically investigate the design of an all-fiber, acousto-optically-modulated single-mode ytterbium-doped double-clad fiber laser, in order to achieve the minimum pulse duration with energies on the order of 100 µJ. These results are then used for experimental realizations. We demonstrate, for the first time to the best knowledge of the authors, in Q-switch single mode architecture, 20 ns pulse width generation with smooth pulse shape, at 20 kHz repetition rate.

Published
2009
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5. Design of all-solid photonic-bandgap fibers for Raman-free propagation

Author

L. Provino, David Pureur, Stéphane Blin, Alain Mugnier, Thierry Chartier, Nicholas Traynor, Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne, Plate-Forme d'Etudes et de Recherche sur les Fibres Optiques Spéciales (Perfos), association PERFOS, Plate-Forme d'Etudes et de Recherche sur les Fibres Optiques Spéciales (PERFOS), Quantel-Lannion (QSA), Quantel, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS), and Chartier, Thierry

Subjects
Amplified spontaneous emission, Optical fiber, Materials science, [SPI.OPTI] Engineering Sciences [physics]/Optics / Photonic, health care facilities, manpower, and services, education, Physics::Optics, 02 engineering and technology, 01 natural sciences, law.invention, 010309 optics, symbols.namesake, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, 0202 electrical engineering, electronic engineering, information engineering, Stokes wave, health care economics and organizations, Photonic crystal, business.industry, Attenuation, stomatognathic diseases, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, symbols, Optoelectronics, Photonics, business, Raman spectroscopy, Raman scattering
Abstract

Stimulated Raman scattering (SRS) is one of the most deleterious effect while propagating high-peak-power nanosecond-long pulses in an optical fiber. The main property of SRS is to shift part of the pump energy to lower frequencies (Stokes wave) at a rate which is proportional to the pump intensity times the Stokes intensity [1]. This effect can therefore be reduced by attenuation of the Stokes wave. Photonic-bandgap fibers (PBGF) are suitable for Raman-free propagation due to their intrinsic spectral filtering properties. The use of an all-solid PBGF for Raman filtering has been demonstrated in [2]. In this paper, we focus on the design of all-solid PBGFs for Raman-free propagation, and evaluate their performance by using an efficient spectrally-resolved model which has recently been developed [3].

Published
2009
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6. Development of a mobile system based on laser-induced breakdown spectroscopy and dedicated to in situ analysis of polluted soils

Author

Martine Potin-Gautier, Bruno Bousquet, T. Boriachon, E. Brasseur, I. Le Hécho, Grégoire Travaillé, P. Wazen, M. Larregieu, A. Diard, S. Tellier, K. Michel-Le Pierres, Lionel Canioni, S. Belbèze, Amina Ismaël, S. Roy, Centre de physique moléculaire optique et hertzienne (CPMOH), Université Sciences et Technologies - Bordeaux 1-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Laboratoire de Chimie Analytique Bio-Inorganique et Environnement (LCABIE), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), QUANTEL, Quantel, and ANTEA

Subjects
In situ, Polluted soils, Soil test, [SDE.MCG]Environmental Sciences/Global Changes, Soil science, 02 engineering and technology, 01 natural sciences, Analytical Chemistry, law.invention, law, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Laser-induced breakdown spectroscopy, Spectroscopy, Instrumentation, LIBS, Moisture, [SDE.IE]Environmental Sciences/Environmental Engineering, 010401 analytical chemistry, In-situ, 021001 nanoscience & nanotechnology, Laser, Data variability, 6. Clean water, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Sample representativeness, Environmental chemistry, Principal component analysis, Soil water, Environmental science, 0210 nano-technology
Abstract

International audience; Principal Components Analysis (PCA) is successfully applied to the full laser-induced breakdown spectroscopy (LIBS) spectra of soil samples, defining classes according to the concentrations of the major elements. The large variability of the LIBS data is related to the heterogeneity of the samples and the representativeness of the data is finally discussed. Then, the development of a mobile LIBS system dedicated to the in-situ analysis of soils polluted by heavy metals is described. Based on the use of ten-meter long optical fibers, the mobile system allows deported measurements. Finally, the laser-assisted drying process studied by the use of a customized laser has not been retained to overcome the problem of moisture.

Published
2008
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7. High loop rate adaptive optics flood illumination ophthalmoscope with structured illumination capability

Author

Pedro Mecê, C. Petit, Serge Meimon, Kate Grieve, Aurélie Bonnefois, Laurent M. Mugnier, Jose A. Sahel, Jessica Jarosz, Michel Paques, Elena Gofas-Salas, DOTA, ONERA, Université Paris Saclay (COmUE) [Palaiseau], Université Paris Saclay (COmUE)-ONERA, Institut de la Vision, Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Paris Adaptive-Optics for Retinal Imaging and Surgery (Paris Group), Quantel Medical, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts (CHNO), and The University of Pittsburgh School of Medicine (Department of Ophtalmology)

Subjects
Male, Optics and Photonics, IMAGE PROCESSING, Light, Image quality, Computer science, RETINAL NERVE FIBER LAYER, Structured illumination microscopy, Image processing, OPTIQUE ADAPTATIVE, 01 natural sciences, 010309 optics, 03 medical and health sciences, 0302 clinical medicine, Optics, OPHTALMIC OPTICS AND DEVICES, 0103 physical sciences, medicine, Humans, OPHTALMOLOGY, FUNCTIONAL MONITORING AND IMAGING, Electrical and Electronic Engineering, Adaptive optics, Engineering (miscellaneous), ACTIVE OR ADAPTIVE OPTICS, Retina, Pixel, Stray light, business.industry, Ophthalmoscopes, OPHTALMOLOGIE, EYE MOVEMENTS, Retinal Vessels, Equipment Design, eye diseases, Atomic and Molecular Physics, and Optics, medicine.anatomical_structure, STRAY LIGHT, Regional Blood Flow, Temporal resolution, 030221 ophthalmology & optometry, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Female, MEDICAL AND BIOLOGICAL IMAGING, business, IMAGE QUALITY, WAVE FRONT SENSING
Abstract

International audience; The design and performance of an adaptive optics flood illumination ophthalmoscope (AO-FIO) platform, based on eye motion and dynamic aberrations experimental analysis, are described. The system incorporates a custom-built real-time controller, enabling up to 70 Hz loop rate without jitter, and an AO-corrected illumination capable of projecting high-resolution features in the retina. Wide-field (2.7°×5.4°) and distortionless images from vessel walls, capillaries, and the lamina cribrosa are obtained with an enhanced contrast and signal-to-noise ratio, thanks to careful control of AO parameters. The high spatial and temporal resolution (image acquisition up to 200 Hz) performance achieved by this platform enables the visualization of vessel deformation and blood flow. This system opens up the prospect of a return to favor of flood illumination adaptive optics systems provided that its high pixel rate and structured illumination capabilities are exploited.; La conception et la performance de l’ophtalmoscope plein champ assisté par Optique Adaptative (OA), basés sur des analyses expérimentales des mouvements et aberrations oculaires, sont décrites. Le système est composé d’un calculateur en temps-réel qui permet d’atteindre une vitesse de boucle d’asservissement de 70Hz. Le système permet aussi la projection de motifs dans la rétine. Grâce au contrôle et la maîtrise d’un système d’Optique Adaptative, des images à grand champ (2.7x5.4°) sans distorsion des différentes régions de la rétine présentent une amélioration de contraste et de rapport signal sur bruit. La haute résolution spatio-temporelle permet également la visualisation des déformations vasculaire et du flux sanguin. Ce système ouvre des nouvelles perspectives en ophtalmoscopie plein-champ, qui pourrait s'imposer dans les années à venir à condition que sa haute résolution temporelle et sa capacité de projeter des motifs d’illumination soient exploitées.

Published
2018
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8. Fixational eye movement: a negligible source of dynamic aberration

Author

Jean-Marc Conan, Pedro Mecê, Serge Meimon, Kate Grieve, Jessica Jarosz, Cyril Petit, Michel Paques, ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Quantel Medical, Institut de la Vision, Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts (CHNO), Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and André, Cécile

Subjects
[SPI.OPTI] Engineering Sciences [physics]/Optics / Photonic, Zernike polynomials, Computer science, WAVE-FRONT SENSING, 01 natural sciences, Deformable mirror, Pupil, Article, DETECTION, 010309 optics, 03 medical and health sciences, symbols.namesake, 0302 clinical medicine, 0103 physical sciences, OPHTHALMOLOGY, Computer vision, [SDV.MHEP.OS]Life Sciences [q-bio]/Human health and pathology/Sensory Organs, Adaptive optics, ACTIVE OR ADAPTIVE OPTICS, OPTIQUE ACTIVE, business.industry, EYE MOVEMENTS, Eye movement, OPHTHALMIC OPTICS AND DEVICES, Atomic and Molecular Physics, and Optics, Fixational eye movements, VISION, [SDV.MHEP.OS] Life Sciences [q-bio]/Human health and pathology/Sensory Organs, 030221 ophthalmology & optometry, symbols, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Artificial intelligence, business, FRONT ONDE, Biotechnology
Abstract

To evaluate the contribution of fixational eye movements to dynamic aberration, 50 healthy eyes were examined with an original custom-built Shack-Hartmann aberrometer, running at a temporal frequency of 236Hz, with 22 lenslets across a 5mm pupil, synchronized with a 236Hz pupil tracker. A comparison of the dynamic behavior of the first 21 Zernike modes (starting from defocus) with and without digital pupil stabilization, on a 3.4s sequence between blinks, showed that the contribution of fixational eye movements to dynamic aberration is negligible. Therefore we highlighted the fact that a pupil tracker coupled to an Adaptive Optics Ophthalmoscope is not essential to achieve diffraction-limited resolution., Pour évaluer la contribution des mouvements oculaires de fixation à l'aberration dynamique, 50 yeux sains ont été examinés avec un aberromètre du type Shack-Hartmann, fonctionnant à une fréquence temporelle de 236Hz, avec 22 micro-lentilles sur une pupille de 5mm, synchronisées avec un suiveur pupillaire de 236Hz. Une comparaison du comportement dynamique des 21 premiers modes de Zernike (à partir de la défocalisation) avec et sans stabilisation numérique de la pupille, sur une séquence de 3.4s entre les clignements, a montré que la contribution des mouvements oculaires de fixation à l'aberration dynamique est négligeable. Par conséquent, nous avons souligné le fait qu'un suiveur pupillaire couplé à un ophtalmoscope assisté par l’Optique Adaptative n'est pas essentiel pour obtenir une résolution limitée par la diffraction.

Published
2018
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9. Phase Locking a Clock Oscillator to a Coherent Atomic Ensemble

Author

Ralf Kohlhaas, Etienne Cantin, Arnaud Landragin, Andrea Bertoldi, Alain Aspect, Philippe Bouyer, Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Fabry / Optique atomique, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Laboratoire Photonique, Numérique et Nanosciences (LP2N), Université Sciences et Technologies - Bordeaux 1-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), Quantel, Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1 (UB)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, education.field_of_study, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Atomic Physics (physics.atom-ph), QC1-999, Local oscillator, Population, Quantum superposition, FOS: Physical sciences, General Physics and Astronomy, 01 natural sciences, Atomic clock, Physics - Atomic Physics, 010305 fluids & plasmas, Superposition principle, Interferometry, Quantum mechanics, 0103 physical sciences, Astronomical interferometer, 010306 general physics, education, Coherence (physics)
Abstract

The sensitivity of an atomic interferometer increases when the phase evolution of its quantum superposition state is measured over a longer interrogation interval. In practice, a limit is set by the measurement process, which returns not the phase, but its projection in terms of population difference on two energetic levels. The phase interval over which the relation can be inverted is thus limited to the interval $[-\pi/2,\pi/2]$; going beyond it introduces an ambiguity in the read out, hence a sensitivity loss. Here, we extend the unambiguous interval to probe the phase evolution of an atomic ensemble using coherence preserving measurements and phase corrections, and demonstrate the phase lock of the clock oscillator to an atomic superposition state. We propose a protocol based on the phase lock to improve atomic clocks under local oscillator noise, and foresee the application to other atomic interferometers such as inertial sensors., Comment: 9 pages, 7 figures

Published
2015
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10. High temporal resolution aberrometry in a 50-eye population and implications for adaptive optics error budget

Author

Cyril Petit, Michel Paques, Pedro Mecê, Jessica Jarosz, Jean-Marc Conan, Serge Meimon, ONERA - The French Aerospace Lab [Châtillon], ONERA-Université Paris Saclay (COmUE), Quantel Medical, and Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts (CHNO)

Subjects
Computer science, Population, 02 engineering and technology, Residual, 01 natural sciences, Article, WAVEFRONT SENSORS, 010309 optics, Optics, 0103 physical sciences, Aberrometry, OPHTALMOLOGY, ABERROMETRY, education, Adaptive optics, ADAPTIVE OPTICS, Wavefront, education.field_of_study, business.industry, Wavefront sensor, 021001 nanoscience & nanotechnology, Frame rate, Atomic and Molecular Physics, and Optics, Temporal resolution, [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, 0210 nano-technology, business, Biotechnology
Abstract

International audience; We formed a database gathering the wavefront aberrations of 50 healthy eyes measured with an original custom-built Shack-Hartmann aberrometer at a temporal frequency of 236 Hz, with 22 lenslets across a 7-mm diameter pupil, for a duration of 20 s. With this database, we draw statistics on the spatial and temporal behavior of the dynamic aberrations of the eye. Dynamic aberrations were studied on a 5-mm diameter pupil and on a 3.4 s sequence between blinks. We noted that, on average, temporal wavefront variance exhibits a n−2 power-law with radial order n and temporal spectra follow a f−1.5 power-law with temporal frequency f. From these statistics, we then extract guidelines for designing an adaptive optics system. For instance, we show the residual wavefront error evolution as a function of the number of corrected modes and of the adaptive optics loop frame rate. In particular, we infer that adaptive optics performance rapidly increases with the loop frequency up to 50 Hz, with gain being more limited at higher rates.

Published
2017
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11. WINDII, the Wind Imaging Interferometer on the Upper Atmosphere Research Satellite

Author

L. L. Cogger, R. H. Wiens, R. L. Gattinger, B. Solheim, O. Peillet, F. Girod, J. F. Brun, D. J. W. Kendall, S. Brune, Charles H. Hersom, Wayne F. J. Evans, E. J. Llewellyn, P. Charlot, Y. J. Rochon, R. H. Hum, D. Harvie, Robert P. Lowe, J. M. Alunni, I. Powell, F. Pasternak, D. L. Desaulniers, J. Wimperis, W. A. Gault, Gordon G. Shepherd, William E. Ward, J. Ohrt, Gérard Thuillier, Institute for Space and Terrestrial Science [Toronto] (ISTS), York University [Toronto], Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Société Quantel [Les Ulis], AIT Advanced Information Technologies Corporation, Centre National d'Études Spatiales [Toulouse] (CNES), Department of Physics and Astronomy [Calgary], University of Calgary, CAL Corporation [Ottawa], Trent University, National Research Council of Canada (NRC), Canadian Space Agency (CSA), University of Saskatchewan [Saskatoon] (U of S), University of Western Ontario (UWO), Matra-Espace [Toulouse], Bertin Technologies, and Interoptics [Ottawa]

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, Soil Science, Aquatic Science, Oceanography, 7. Clean energy, 01 natural sciences, Wind speed, law.invention, 010309 optics, symbols.namesake, Geochemistry and Petrology, law, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), Astrophysics::Solar and Stellar Astrophysics, Emission spectrum, Physics::Atmospheric and Oceanic Physics, 0105 earth and related environmental sciences, Earth-Surface Processes, Water Science and Technology, Remote sensing, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Ecology, Airglow, Astrophysics::Instrumentation and Methods for Astrophysics, Paleontology, Michelson interferometer, Forestry, Wavelength, Interferometry, Geophysics, 13. Climate action, Space and Planetary Science, Physics::Space Physics, symbols, Environmental science, Satellite, Doppler effect
Abstract

International audience; The WIND imaging interferometer (WINDID was launched on the Upper Atmosphere Research Satellite (UARS) on September 12, 1991. This joint project, sponsored by the Canadian Space Agency and the French Centre National d'Etudes Spatiales, in collaboration with NASA, has the responsi- bility of measuring the global wind pattern at the top of the altitude range covered by UARS. WINDII measures wind, temperature, and emission rate over the altitude range 80 to 300 km by using the visible region airglow emission from these altitudes as a target and employing optical Doppler interferometry to measure the small wavelength shifts of the narrow atomic and molecular airglow emission lines induced by the bulk velocity of the atmosphere carrying the emitting species. The instrument used is an all-glass field-widened achromatically and thermally compensated phase- stepping Michelson interferometer, along with a bare CCD detector that images the airglow limb through the interferometer. A sequence of phase-stepped images is processed to derive the wind velocity for two orthogonal view directions, yielding the vector horizontal wind. The process of data analysis, including the inversion of apparent quantities to vertical profiles, is described.

Published
1993
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