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Conference on current developments in lens design and optical engineering XXI

作者： Allain, Guillaume Thibault, Simon Ctr Opt Photon & Laser Quebec City PQ Canada Univ Laval Dept Phys Genie Phys & Opt Quebec City PQ Canada

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

The design of high quality very wide-angle optical systems (FFOv > 100 degrees) relies on distortion to obtain a sufficient resolution at, usually, the center of the field of view. Using distortion shape as a parameter during optimization to reach a magnification target is a common technique to achieve optical foveation during the lens design process. This method allows resolution enhancement at selected parts of the field of view since less care is given to parts of the image that are deemed less important. However, accurate control of distortion can be a challenge during optical design since the standard aspherics polynomials don't correlate directly to image magnification. This may in fact slow down optimization since the merit function is much less optimized to approach a solution. In this paper, we address this problem by presenting a method to simplify distortion control during the optical design phase. To achieve this, the use of orthogonal polynomials is used for defining the optical surface shape and will then be used to compare the height of the image plane at a given field of view. We show that in the case of simple and paraxial system, this process is orthogonal and achieve a solution in a single optimization step. We will finally discuss the limits of this method and how it applies to modern lens design problems.

关键词： optical design Foveated imaging Distortion Control Orthogonal polynomials Shape specification

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STATUS OF AEOLUS-2 MISSION PRE-DEvELOPMENT ACTIvITIES

STATUS OF AEOLUS-2 MISSION PRE-DEVELOPMENT ACTIVITIES

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2022 International Conference on Space Optics, ICSO 2022

作者： Heliere, Arnaud Wernham, Denny Mason, Graeme Fehr, Thorsten De villele, Geraud Corselle, Bertrand Lecrenier, Olivier Belhadj, Thomas Bravetti, Paolo Arnaud, Sylvain Bon, Didier Lingot, Philippe Foulon, Roland Marchais, Denis Olivier, Mickael D'Ottavi, Alessandro verzegnassi, Fulvia Mondello, Alessia Coppola, Francesco Landi, Guglielmo Hoffmann, Hans-Dieter Esser, Dominik Prieto, Lucia Perez Wührer, Christian Rivers, Christopher European Space Agency Airbus Defence and Space SAS Germany Leonardo Spa Germany Airbus Defence and Space Gmbh Germany Ray Bell Teledyne E2V

ISBN: (纸本)9781510668034

The European Space Agency's (ESA) Aeolus satellite was launched on 22 August 2018 from Centre Spatial Guyanais in Kourou, French Guyana. The Aeolus data has been extensively analysed by a number of meteorological centres and found to have a positive impact on NWP forecasts, particularly in the tropics and polar regions. These positive results, along with the successful in-orbit demonstration of the measurement concept and associated technologies utilised on Aeolus, resulted in a statement of interest from EUMETSAT in a future, operational DWL mission in the 2030 to mid-2040's timeframe and a request to ESA to carry out the necessary pre-development activities for such a mission. This paper will describe the current status of instrument predevelopment activities that are being performed in the frame of a potential Aeolus-2 mission. The main inputs for a future Doppler Wind Lidar (DWL) instrument that have been used are: lessons learned from the Aeolus development phases and the in-orbit operations and performance;initial inputs from EUMETSAT including a total mission lifetime of higher than 10-15 years utilizing 2 spacecraft (implying a lifetime of 5.5 years for each) with a launch of the first satellite in 2030, increased robustness and operability of the instrument, and an emphasis on reduction of recurrent costs;the maximum utilization of the demonstrated design heritage;and a number of recommendations for the requirements of a future DWL mission from the Aeolus Scientific Advisory Group (ASAG). These inputs have been collated and combined into a set of preliminary requirements which have been used as the basis for a dedicated Instrument Consolidation Study. An extensive review and trade-off of the above inputs by Airbus Defence & Space, ESA, and independent experts, resulted in the decision to baseline a bi-static instrument design. In addition, three instrument subsystem pre-development activities are currently running: two laser transmitter pre-developments and

关键词： optical radar

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The importance of Petzval correction in generalized Offner designs 11

The importance of Petzval correction in generalized Offner d...

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Conference on current developments in lens design and optical engineering XXI

作者： Rogers, John R. Rakich, Andrew Synopsys Inc 199 S Los Ro Bles Ave Pasadena CA 91101 USA Mersenne Opt Consulting 41 Rimu Rd Raumati Beach 5032 Paraparaumu New Zealand

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

In this paper we examine the third-order aberrations of the "generalized Offner" family of designs comprising three concentric mirrors, with the first and third mirrors being not necessarily identical in radius and including the possibility that the object might be displaced from the common centers of curvature. We develop analytic expressions relating the first-order and third-order properties of the system to the radii of the three mirrors and to the object distance. Although one might expect a ring-field system to be relatively tolerant of field curvature, we show that the Petzval Sum affects the other aberrations in an extraordinary manner.

关键词： lens design aberration theory monocentric concentric

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design of an anastigmatic three-mirror telescope using freeform surfaces 11

Design of an anastigmatic three-mirror telescope using freef...

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Conference on current developments in lens design and optical engineering XXI

作者： Alvarado-Martinez, J. J. Granados-Agustin, F. S. vazquez-y Montiel, S. Cornejo-Rodriguez, A. A. INAOE Luis Enrique Erro 1 Sta Maria Tonanzintla Cholula Pue Mexico UIEPA Los Ilanos Kilometro 1 San Andres Tlayehualanci Ahuacatlan Pue Mexico

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

This paper proposes the design of an anastigmatic three-mirror telescope using freeform surfaces for the correction of spherical aberration, coma, astigmatism, and field curvature, allowing a wide field of view (FOv) and high resolution. For the structure of this telescope, it is proposed to use only two optical elements where the primary and tertiary mirrors are integrated into an only optical element and the secondary mirror in the other, thus achieving a considerable reduction in the difficulty of alignment and assembly. To achieve a high performance of the telescope, the system was decentered (off-axis design), avoiding the loss of energy due to the obscuration of the M-2 in the on-axis system. In addition, to solve the difficult access to the focus.

关键词： optical design three-mirror system freeform on-axis system off-axis system

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Comparison of passive athermalization results of LWIR optical designs utilizing different infrared optical materials 11

Comparison of passive athermalization results of LWIR optica...

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Conference on current developments in lens design and optical engineering XXI

作者： Kucukcelebi, Doruk Sakarya, Dogan Ugur Kemalpasa Mahallesi Sehit Yuzbasi Adem Kutlu TR-06780 Ankara Turkey

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

In this paper, different optical designs, which are composed of different LWIR optical materials, are utilized for passive athermalization and their performance in athermalization are analyzed. The optical designs are carried out by preserving the athermal property as well as keeping the image quality at higher levels within the working temperature between -40 degrees C and +60 degrees C. Our designs consist of two different infrared optical elements to maintain the focus positions as stable as possible within the working temperature. The passive athermalization process begins with the calculation of athermalization conditions of candidate material properties. By taking into account these conditions, athermal material pairs are chosen. The optical design begins with an optimization process using paraxial optics. In order to reduce aberrations such as coma, astigmatism, spherical and chromatic, aspherical surfaces are utilized during the optimization process. At the end of the design phase, the performance of different configurations of athermal optical material pairs, which are enclosed by aluminum alloy housing material, are presented.

关键词： Athermalization infrared optical design two-element optical material pair Long Wave Infrared (LWIR)

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Ultrashort Throw lenses with Catadioptric Relay Suitable for Flat and Curved Screens 11

Ultrashort Throw Lenses with Catadioptric Relay Suitable for...

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Conference on current developments in lens design and optical engineering XXI

作者： Nishikawa, Jun Nishiyama, Mariko Sony Corp R&D Ctr Atsugi Kanagawa Japan

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

In the past two decades, to realize high resolutions and low distortions while miniaturizing optical systems, various ultrashort throw lenses (USTs) have been proposed. In this work, ultrashort throw lenses with a catadioptric relay (USTCRs) with rotational symmetry are proposed to provide the solution. First, the initial design method of the USTCR and the optimized design solution are presented. Although this optical system with a throw ratio of 0.26:1 has resolutions and distortions equivalent to those of conventional UST with one aspherical mirror, the depth of focus (DOF) on the panel side becomes 1.31 times deeper with appropriate corrections of the field curvature. The total length of the lens is reduced to 0.89 times, the area of the main mirror is reduced to 0.22 times, and the number of lenses is reduced from 13 to 9 elements. Based on these results, several optical designs for USTCR have been tried and an optical design with robustness has been proposed. By optimizing the power of each lens group, the decenter sensitivity improved to 0.46 times for parallel decenter and 0.55 times for tilt decenter. By optimizing glass materials, the shift of focal plane can be suppressed to 0.56 times when the temperature increases by 30 degrees C. An USTCR suited for a curved screen has also been proposed. By introducing appropriate constraints that correct distortions, high resolutions and low distortions have been realized while maintaining a wide angle of view. USTCRs suited for various curved screens are currently underway.

关键词： ultrashort throw projector projection lens catadioptric relay lens lens design lens system design concave mirror curved screen mirror system design

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Using optical diagnostics for near field blast testing 8th

Using optical diagnostics for near field blast testing

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8th International Conference on Structural engineering, Mechanics and Computation (SEMC)

作者： Langdon, G. S. Curry, R. J. Rigby, S. E. Pickering, E. G. Clarke, S. D. Tyas, A. Gabriel, S. Yuen, S. Chung Kim von Klemperer, C. J. Univ Sheffield Dept Civil & Struct Engn Sheffield S Yorkshire England Univ Cape Town BISRU Dept Mech Engn Rondebosch South Africa Univ Cape Town Dept Mech Engn Rondebosch South Africa

ISBN: (纸本)9781003348443

The ability to measure the structural and material response to air-blast loading is vital to developing a proper understanding of near-field blast loading and response. Computational modelling has advanced significantly but, until recently, experimental techniques lagged behind. This paper discusses recent advances in these experimental techniques. The first part describes a bilateral test programme between the UK and South Africa. The high-speed imaging and digital image correlation system at Cape Town gives repeatable and accurate impulse distributions across a central strip of a panel, useful for model validation. Flexural wave behaviour was observed from the transient velocity and displacement profiles, giving good insights into the mechanics of plate response from blast loads. The second part demonstrates the value of high-speed stereo-imaging for measuring the transient response of blast loaded fibre reinforced polymer panels and sandwich structures. The peak displacements. elastic rebounds and transient oscillations provide valuable insights into the damage propagation within these types of structures. The final part of the paper describes some of the continued developments since the success of those early trials, resulting in a new optical diagnostics for blast capability at the University of Sheffield. The imaging system operates at higher frame rates and can cover a wider region of interest on the structure. Ultra-high speed imaging is also shown to be a useful tool for visualising detonations fronts in explosive charges and the expanding fireball.

关键词： Fiber reinforced plastics

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designing for Degradation: Transient Devices Enabled by (Nano)Cellulose

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ADvANCED MATERIALS 2024年第0期 e2401560页

作者： Andrew, Lucas J. Lizundia, Erlantz MacLachlan, Mark J. Univ British Columbia Dept Chem 2036 Main Mall Vancouver BC V6T 1Z1 Canada Univ Basque Country UPV EHU Fac Engn Bilbao Dept Graph Design & Engn Projects Life Cycle Thinking Grp Bilbao 48013 Spain Basque Ctr Mat Applicat & Nanostruct BCMaterials UPV EHU Sci Pk Leioa 48940 Spain Univ British Columbia Stewart Blusson Quantum Matter Inst 2355 East Mall Vancouver BC V6T 1Z4 Canada Kanazawa Univ WPI Nano Life Sci Inst Kanazawa 9201192 Japan UBC BioProd Inst 2385 East Mall Vancouver BC V6T 1Z4 Canada

Transient technology involves materials and devices that undergo controlled degradation after a reliable operation period. This groundbreaking strategy offers significant advantages over conventional devices based on non-renewable materials by limiting environmental exposure to potentially hazardous components after disposal, and by increasing material circularity. As the most abundant naturally occurring polymer on Earth, cellulose is an attractive material for this purpose. Besides, (nano)celluloses are inherently biodegradable and have competitive mechanical, optical, thermal, and ionic conductivity properties that can be exploited to develop sustainable devices and avoid the end-of-life issues associated with conventional systems. Despite its potential, few efforts have been made to review current advances in cellulose-based transient technology. Therefore, this review catalogs the state-of-the-art developments in transient devices enabled by cellulosic materials. To provide a wide perspective, the various degradation mechanisms involved in cellulosic transient devices are introduced. The advanced capabilities of transient cellulosic systems in sensing, photonics, energy storage, electronics, and biomedicine are also highlighted. current bottlenecks toward successful implementation are discussed, with material circularity and environmental impact metrics at the center. It is believed that this review will serve as a valuable resource for the proliferation of cellulose-based transient technology and its implementation into fully integrated, circular, and environmentally sustainable devices. Recent progress in transient devices enabled by (nano)cellulosic materials is reviewed. Transiency mechanisms, advantages of nanocelluloses, and a suite of applications are discussed. A circular thinking approach coupled with life cycle assessment is applied to critically revisit the potential, advantages, and challenges of nanocellulose-enabled transient devices for future ma

关键词： biodegradable circular economy nanocellulose sustainability transiency

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Inverse designed flat optics with multilevel diffractive lenses 11

Inverse designed flat optics with multilevel diffractive len...

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Conference on current developments in lens design and optical engineering XXI

作者： Banerji, Sourangsu Meem, Monjurul Majumder, Apratim Garcia, Juan C. Hon, Philip Pies, Christian Oberbiermann, Timo Menon, Rajesh Rodriguez, Berardi Sensale Univ Utah Elect & Comp Engn Salt Lake City UT 84102 USA Northrop Grumman Corp NG Next Redondo Beach CA 90278 USA Heidelberg Instruments Mikrotech Heidelberg Germany Oblate Opt Inc San Diego CA 92130 USA

ISBN: (数字)9781510637719

ISBN: (纸本)9781510637719

In conventional imaging, the information transfer from the object to the image plane is accomplished either with the help of a traditional lens that performs a one-to-one mapping or an unconventional lens that performs a one-to-many mapping. In the first case, the image is formed directly, whereas in the second case, the image is formed after a computation. The conventional lens approach is preferred in most cases due to the high signal-to-noise ratio achievable at each image pixel. By appealing to the fact that for most of the imaging applications, it is only the intensity, which is measured by the detector, the phase of the field in the image or focal plane is a free parameter, something that comes from the inverse diffraction transform. Therefore, it is easy to visualize that this phase of the plane wave after it transmits the lens can have multiple forms. Hence, the final choice can be made based upon specific application tailored requirements like achromaticity, depth-of-focus, wide-angle imaging, etc. This concept was exploited to design an achromatic MDL via inverse design across almost the entire electromagnetic spectrum (lambda = 450 nm to 15 mu m). Furthermore, a MDL with a Field Of view (FOv) up to 50 degrees for wide-angle imaging as well as a MDL to enable an extreme Depth of Focus (EDOF) imaging of up to 6 m in the NIR were also designed.

关键词： Inverse design Diffractive lens Imaging

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Microfluidic fabrication with silver nanowires for optofluidic structures with three-dimensional operation

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SENSORS AND ACTUATORS A-PHYSICAL 2020年 315卷 112297-112297页

作者： Del Rosso, Michelle Lepard, Sydney Eswar, Rahul Collier, Christopher M. Univ Guelph Sch Engn Guelph ON N1G 2W1 Canada

With the current design of modern optical lens technology, the optical parameters and field-of-view are restricted, preventing maximum functionality. Such restrictions can be mitigated with the implementation of a three-dimensional compound-eye lens, however, the fabrication of this three-dimensional compound-eye lens is associated with several challenges. Such challenges include the development of a semi-transparent and flexible electrode material and the operation and adherence of out-of-plane optofluidic lenses to oblique interfaces. This work addresses these challenges through two experimental analyses. The first experimental analysis is a study of silver nanowires with feature size of approximately 90 nm for use as a flexible and semi-transparent electrode material, and the effects of filtering and processing methods on the electrode sheet resistance. With optimal preparation of the silver nanowires, the fabricated electrode is seen to have favourable properties for this application. The second experimental analysis is a study of the optimal hydrophobic coating for minimal hysteresis and the optical operation of out-of-plane optofluidic lenses situated on oblique interfaces, as is required for peripheral out-of-plane optofluidic lenses in a three-dimensional compound-eye lens. The out-of-plane optofluidic lenses are seen to have favourable operation and voltage control with minimal hysteresis. The results show promise towards development of wide field-of-view systems with tunable optical parameters. (C) 2020 Elsevier B.v. All rights reserved.

关键词： Microdroplet Microfluidic fabrication Out-of-plane optofluidic lens array Silver nanowires Three-dimensional compound-eye lens

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