Dr. Steffan A. E. Lewis Profile

Dr. Steffan A. E. Lewis

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Author

Publications (16)

Proceedings Article | 6 September 2022 Poster + Paper

Estimation of the position of the ELT prefocal station main axis in operation

Edoardo Maria Alberto Redaelli, Carlo Zanoni, Sebastian Schmid, Paul Jolley, Martin Brinkmann, Ulrich Lampater, Steffan Lewis

Proceedings Volume 12182, 121822C (2022) https://doi.org/10.1117/12.2629187

KEYWORDS: Sensors, Finite element methods, Computer simulations, Telescopes, Superposition, Stars, Spherical lenses, Retroreflectors, Photovoltaics, Motion measurement

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Proceedings Article | 29 August 2022 Poster + Paper

The manufacturing and AIV plan for the Extremely Large Telescope Prefocal Stations

Asier Larringan, Gaizka Murga, Steffan Lewis, Paul Jolley

Proceedings Volume 12182, 1218238 (2022) https://doi.org/10.1117/12.2629221

KEYWORDS: Manufacturing, Optics manufacturing, Optical fabrication, Metrology, Optical alignment, Mirrors, Inspection, Optical fabrication equipment, Control systems, Control systems design

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SPIE Journal Paper | 5 April 2022

Structural, thermal, and optical performance analysis applied to subsystems of the European Extremely Large Telescope

Ronald Holzlöhner, Aglaé Kellerer, Ulrich Lampater, Steffan Lewis, Carlo Zanoni

JATIS, Vol. 8, Issue 02, 021504, (April 2022) https://doi.org/10.1117/12.10.1117/1.JATIS.8.2.021504

KEYWORDS: Thermography, Optical components, Sensors, Mirrors, Computer aided design, Motion models, Telescopes, Systems modeling, Integrated modeling, Performance modeling

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Proceedings Article | 13 December 2020 Presentation + Paper

The final design for the Extremely Large Telescope prefocal stations

Asier Larringan, Amaya Múgica, Gaizka Murga, Paul Jolley, Steffan Lewis

Proceedings Volume 11445, 114451G (2020) https://doi.org/10.1117/12.2559880

KEYWORDS: Telescopes, Sensors, Large telescopes, Control systems, Optical instrument design, Mirrors, Stars, Wavefront sensors, Cameras, Diagnostics

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Proceedings Article | 9 July 2018 Paper

Extremely Large Telescope Prefocal Station A system concept

S. A. Lewis, E. Brunetto, A. Förster, C. Frank, I. Guidolin, S. Guisard, P. Hammersley, R. Holzlöhner, P. Jolley, J. Kosmalski, U. Lampater, E. Marchetti, P. La Penna, T. Pfrommer, P. Zuluaga

Proceedings Volume 10700, 107001B (2018) https://doi.org/10.1117/12.2313535

KEYWORDS: Telescopes, Sensors, Mirrors, Metrology, Wavefront sensors, Error analysis, Cameras, Interfaces, Imaging systems, Wavefronts

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Proceedings Article | 6 July 2018 Paper

MELT: an optomechanical emulation testbench for ELT wavefront control and phasing strategy

T. Pfrommer, S. Lewis, J. Kosmalski, P. La Penna, C. Frank, I. Guidolin, S. Leveque, A.-L. Cheffot, H. Bonnet, N. Kornweibel, J. Spyromilio

Proceedings Volume 10700, 107003F (2018) https://doi.org/10.1117/12.2313537

KEYWORDS: Telescopes, Sensors, Wavefronts, Control systems, Mirrors, Diagnostics, Interfaces, Near infrared, Imaging systems, Wavefront sensors

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We present an optomechanical test bench setup (MELT) for testing and validating key functionalities to be used on the Extremely Large Telescope (ELT) during the periods of system verification, wavefront control commissioning, through the handover to science, up to regular diagnostic, monitoring, and validation tasks during operations.

The main objectives of MELT are to deploy and validate the telescope control system, to deploy and validate wavefront control algorithms for commissioning and operations, as well as to produce and validate key requirements for the phasing and diagnostic station (PDS) of the ELT.

The purpose of MELT is to deploy optomechanical key components such as a segmented primary mirror, a secondary mirror on a hexapod, an adaptive fourth mirror, and a fast tip/tilt mirror together with their control interfaces that emulate the real telescope optomechanical conditions. The telescope control system, deployed on MELT can test control schemes with the active mounts emulating the real ELT optomechanical control interfaces.

The presented optomechanical setup uses the Active Segmented Mirror (ASM) with its piezo-driven 61 segments and a diameter of 15 cm. It was designed, built, and used on sky during the Active Phasing Experiment (APE).

Several beam paths after the telescope optical train on MELT are conditioned and guided to wavefront sensors and cameras, sensitive to wavelength bands in the visible and infrared to emulate wavefront commissioning and phasing tasks. This optical path resembles part of the phasing and diagnostics station (PDS) of the ELT, which is used to acquire the first star photons through the ELT and to learn the usage and control of all the ELT optomechanics. The PDS will be developed, designed, and built in-house at ESO. MELT helps its design by providing a detailed test setup for defining and deploying system engineering tasks, such as detailed functional analysis, definition of tasks to be carried out, and technical requirements, as well as operational commissioning aspects.

The bench test facility MELT will in the end help us to be as much as possible prepared when the telescope sends the first star light through the optical train to be able to tackle the unforeseeable problems and not be caught up with the foreseeable ones.

Proceedings Article | 9 August 2016 Paper

Progress along the E-ELT instrumentation roadmap

Suzanne Ramsay, Mark Casali, Michele Cirasuolo, Sebastian Egner, Peter Gray, Juan Carlos Gonzáles Herrera, Peter Hammersley, Christoph Haupt, Derek Ives, Lieselotte Jochum, Markus Kasper, Florian Kerber, Steffan Lewis, Vincenzo Mainieri, Antonio Manescau, Enrico Marchetti, Sylvain Oberti, Paolo Padovani, Christian Schmid, Johannes Schimpelsberger, Ralf Siebenmorgen, Orsolya Szecsenyi, Roberto Tamai, Joël Vernet

Proceedings Volume 9908, 99081T (2016) https://doi.org/10.1117/12.2232407

KEYWORDS: Spectrographs, Adaptive optics, Cameras, Telescopes, Spectral resolution, Interfaces, Space telescopes, Laser guide stars, Mirrors, Sensors

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Proceedings Article | 27 July 2016 Paper

Comparison between observation and simulation of sodium LGS return flux with a 20W CW laser on Tenerife

R. Holzlöhner, D. Bonaccini Calia, D. Bello, D. Budker, M. Centrone, I. Guidolin, W. Hackenberg, S. Lewis, G. Lombardi, I. Montilla, F. Pedichini, F. Pedreros Bustos, T. Pfrommer, M. Reyes Garcia Talavera, S. Rochester

Proceedings Volume 9909, 99095E (2016) https://doi.org/10.1117/12.2233072

KEYWORDS: Sodium, Optical simulations, Laser guide stars, Continuous wave operation, Polarization, Laser systems engineering, Laser guide stars, Optical simulations, Magnetism, Laser processing, Fiber lasers, Laser applications

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Proceedings Article | 27 July 2016 Paper

Prefocal station mechanical design concept study for the E-ELT

Paul Jolley, Enzo Brunetto, Christoph Frank, Steffan Lewis, Enrico Marchetti

Proceedings Volume 9906, 99062H (2016) https://doi.org/10.1117/12.2232957

KEYWORDS: Space telescopes, Telescopes, Optical sensing, Sensors, Mechanical engineering, Mirrors, Optical instrument design, Kinematics, Computer aided design, Earthquakes

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Proceedings Article | 27 July 2016 Paper

Sodium vapor cell laser guide star experiments for continuous wave model validation

Felipe Pedreros Bustos, Ronald Holzlöhner, Dmitry Budker, Steffan Lewis, Simon Rochester

Proceedings Volume 9909, 99095P (2016) https://doi.org/10.1117/12.2232524

KEYWORDS: Absorption, Sodium, Laser guide stars, Continuous wave operation, Polarization, Electroluminescent displays, Chemical species, Magnetism, Mesosphere, Spectrum analysis

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Proceedings Article | 26 July 2016 Paper

AO WFS detector developments at ESO to prepare for the E-ELT

Mark Downing, Mark Casali, Gert Finger, Steffan Lewis, Enrico Marchetti, Leander Mehrgan, Suzanne Ramsay, Javier Reyes

Proceedings Volume 9909, 990914 (2016) https://doi.org/10.1117/12.2232504

KEYWORDS: Adaptive optics, Detector development, Sensors, CMOS sensors, Cameras, Imaging systems, Quantum efficiency, CMOS sensors, Telescopes, Near infrared, Optical instrument design

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Proceedings Article | 7 August 2014 Paper

Assembly and test results of the AOF laser guide star units at ESO

W. Hackenberg, D. Bonaccini Calia, B. Buzzoni, M. Comin, C. Dupuy, F. Gago, I. Guidolin, R. Guzman, R. Holzloehner, L. Kern, J. Kirchbauer, S. Lewis, J. Lizon, S. McLay, T. Pfrommer, M. Quattri, J. Quentin, R. Ridings

Proceedings Volume 9148, 91483O (2014) https://doi.org/10.1117/12.2057167

KEYWORDS: Telescopes, Mirrors, Laser guide stars, Interfaces, Calibration, Adaptive optics, Wavefronts, Temperature metrology, Camera shutters, Lasers

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Proceedings Article | 21 July 2014 Paper

ESO adaptive optics facility progress and first laboratory test results

Robin Arsenault, Pierre-Yves Madec, Jérome Paufique, Paolo La Penna, Stefan Stroebele, Elise Vernet, Jean-Francois Pirard, Wolfgang Hackenberg, Harald Kuntschner, Johann Kolb, Nicolas Muller, Aurea Garcia-Rissmann, Miska Le Louarn, Paola Amico, Norbert Hubin, Jean-Louis Lizon, Rob Ridings, Pierre Haguenauer, Jose Abad, Gerhard Fischer, Volker Heinz, Mario Kiekebusch, Javier Argomedo, Ralf Conzelmann, Sebastien Tordo, Rob Donaldson, Christian Soenke, Philippe Duhoux, Enrico Fedrigo, Bernard Delabre, Andrea Jost, Michel Duchateau, Mark Downing, Javier Reyes Moreno, Antonio Manescau, Domenico Bonaccini Calia, Marco Quattri, Christophe Dupuy, Ivan Guidolin, Mauro Comin, Ronald Guzman, Bernard Buzzoni, Jutta Quentin, Steffan Lewis, Paul Jolley, Max Kraus, Thomas Pfrommer, Roberto Biasi, Daniele Gallieni, Remko Stuik, Wilhelm Kaenders, Bernhard Ernstberger, Axel Friedenauer

Proceedings Volume 9148, 914802 (2014) https://doi.org/10.1117/12.2054859

KEYWORDS: Adaptive optics, Telescopes, Cameras, Laser guide stars, Wavefront sensors, Calibration, Turbulence, Actuators, Stars, Space telescopes

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Proceedings Article | 13 September 2012 Paper

ESO adaptive optics facility progress report

Robin Arsenault, Pierre-Yves Madec, Jerome Paufique, Paolo La Penna, Stefan Stroebele, Elise Vernet, Jean-Francois Pirard, Wolfgang Hackenberg, Harald Kuntschner, Lieselotte Jochum, Johann Kolb, Nicolas Muller, Miska Le Louarn, Paola Amico, Norbert Hubin, Jean-Louis Lizon, Rob Ridings, Jose Abad, Gert Fischer, Volker Heinz, Mario Kiekebusch, Javier Argomedo, Ralf Conzelmann, Sebastien Tordo, Robert Donaldson, Christian Soenke, Philippe Duhoux, Enrico Fedrigo, Bernard Delabre, Andreas Jost, Michel Duchateau, Mark Downing, Javier Moreno, Reinhold Dorn, Antonio Manescau, Domenico Bonaccini Calia, Marco Quattri, Christophe Dupuy, Ivan Guidolin, Mauro Comin, Ronald Guzman, Bernard Buzzoni, Jutta Quentin, Steffan Lewis, Paul Jolley, Maximilian Kraus, Thomas Pfrommer, Roberto Biasi, Daniele Gallieni, Clementine Bechet, Remko Stuik

Proceedings Volume 8447, 84470J (2012) https://doi.org/10.1117/12.926074

KEYWORDS: Telescopes, Adaptive optics, Mirrors, Space telescopes, Wavefront sensors, Sensors, Optics manufacturing, Actuators, Control systems, Interfaces

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Proceedings Article | 13 September 2012 Paper

The ESO transportable LGS Unit for measurements of the LGS photon return and other experiments

D. Bonaccini Calia, I. Guidolin, A. Friedenauer, M. Hager, V. Karpov, T. Pfrommer, R. Holzlöhner, S. Lewis, W. Hackenberg, G. Lombardi, M. Centrone, F. Pedichini

Proceedings Volume 8450, 84501R (2012) https://doi.org/10.1117/12.926898

KEYWORDS: Telescopes, Sodium, Continuous wave operation, Pulsed laser operation, Polarization, Laser guide stars, Adaptive optics, Wavefront sensors, Wavefronts, Receivers

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Proceedings Article | 28 July 2010 Paper

PM fiber lasers at 589nm: a 20W transportable laser system for LGS return flux studies

Domenico Bonaccini Calia, Axel Friedenauer, Vladimir Protopopov, I. Guidolin, Luke Taylor, Vladimir Karpov, Manfred Hager, Wallace R. Clements, Bernhard Ernstberger, Steffan Lewis, Wilhelm Kaenders

Proceedings Volume 7736, 77361U (2010) https://doi.org/10.1117/12.857991

KEYWORDS: Fiber lasers, Radiofrequency ablation, Laser stabilization, Telescopes, Laser guide stars, Polarization, Pulsed laser operation, Second-harmonic generation, Bragg cells, Lasers

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Showing 5 of 16 publications

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