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Dorénavant, l’école se doit de développer une culture nourrie par la collégialité de tous les acteurs qui amène la direction de l’école et les enseignants à oeuvrer ensemble comme collègues tout en cherchant à être apprenants les uns des autres dans l’amélioration de leur potentiel, voire du potentiel de l’équipe tout entière (Gather-Thurler, 2000). Cette équipe devrait fonctionner comme une communauté d’apprentissage où les membres apprennent les uns des autres et où le leadership est exercé à tour de rôle par les diverses personnes en tenant compte de leurs préoccupations à un moment donné. La question qui se pose est la suivante : comment peut-on favoriser un tel mode de fonctionnement? Cet article fait état d’une recherche où l’utilisation de la dynamique causale a servi à mieux définir les facteurs favorables à l’implantation réussie d’une communauté d’apprentissage professionnelle. Le groupe a identifié plusieurs facteurs qui ont été regroupés de la façon suivante : 1) le leadership de la direction d’école et des enseignants, 2) des attitudes positives pour travailler en collaboration telles que l’ouverture d’esprit, l’engagement, la volonté de partager ses connaissances, de s’entraider ainsi que de prendre des risques, l’humilité pour remettre en question le statut quo, le respect des autres, la confiance, 3) les ressources, 4) le temps pour discuter et échanger, 5) les données sur les résultats des élèves. Cet écrit fournit également aux directions d’école des occasions de réflexion sur la façon de transformer leur rôle pour laisser plus de place au dialogue collaboratif., Schools must develop a culture nourished by collegiality, leading administrators and teachers to work together as colleagues while learning from each other and improving their potential, and therefore the potential of the entire team (Gather-Thurler, 2000). This team should function as a learning community where members learn from each other and where a variety of people take turns as leaders, depending on the concerns at any given moment. The following question was asked: How can this type of working method be promoted? This article describes research using the causal dynamic to better define factors that would encourage the successful implantation of a professional learning community. The group identified several factors, grouped together as follows: 1) leadership of school administration and teachers, 2) positive attitudes for working in collaboration, such as open mindedness, commitment, the desire to share knowledge and help each other and take risks, the humility to question the status quo, respect for others, trust, 3) resources, 4) time for discussions and exchanges, 5) data on student results. This article also offers school administrators opportunities for reflection on how to transform their roles in order to leave more room for collaborative dialogue., De ahora en adelante, la escuela debe desarrollar una cultura alimentada por la colegialidad de todos los actores, lo que conduce a la dirección de la escuela y a los maestros a trabajar en tanto que colegas que tratan de aprender unos de otros a mejorar su potencial, incluso el potencial de todo el equipo (Gather – Thurler, 2000). Ese equipo deberá funcionar como una comunidad de aprendizaje en la cual los miembros aprenden los unos de los otros y en la cual las diversas personas ejercen el liderazgo cada quien a su turno, tomando en consideración sus preocupaciones a un momento dado. La cuestión que surge es la siguiente: ¿Cómo se puede favorecer esa manera de funcionar? Este artículo rinde cuentas de una investigación en la cual la utilización de la dinámica causal sirvió a mejorar la definición de los factores favorables al logro de la implantación de una comunidad de aprendizaje profesional. El grupo identificó varios factores que fueron reagrupados de la siguiente manera: 1) el liderazgo de la dirección de la escuela y de los maestros, 2) las actitudes positivas para trabajar en colaboración tales que la amplitud de miras, el compromiso, la voluntad de compartir sus conocimientos, de ayudarse mutuamente y de correr riesgos, la humildad de cuestionar el estatus quo, el respeto de los demás y la confianza, 3) los recursos, 4) el tiempo par poder discutir e intercambiar, 5) los datos sobre los resultados de los alumnos. Este texto ofrece asimismo a la dirección de las escuelas la ocasión de reflexionar sobre la manera de transformar su rol para otorgar más espacio al dialogo colaborativo.

Since the release of its first microbolometric camera developed for terahertz (THz) wavelengths in 2009 [1], INO has been continually working to improve the quality of its THz images. This paper presents an overview of the evolution of INO’s THz imaging system, with a particular focus on the optical elements.

Imaging in the Terahertz (THz) and millimeter-wave (mm-wave) bands offer advantages over doing do in other conventional bands, such as the visible, infrared (IR). The THz band ranges from 300 GHz to 3 THz or in wavelength, 1 mm to 100 μm. These longer wavelengths allows THz radiation to pass unobscured through some materials allowing for imaging hidden threats or defects within such materials. Going further, millimeter-waves cover the spectral band of 30 – 300 GHz, or 10 cm to 1 mm. In addition to passing through denser materials, they also have much less atmospheric absorption, thus are ideal for imaging in adverse weather conditions. In the THz/mm-wave, the greatest challenge to real-time active imaging was previously the lack of compact sensor arrays. INO has overcome this by optimizing its microbolometer focal plane array (originally developed for the infrared) for the longer wavelengths, covering both the THz and mm-wave bands. The remaining challenge for active imaging is how to obtain useful imagery using coherent sources. INO has been working on improving the quality of the illumination beam over the past few years, as well as designing high quality fast imaging optics. This paper will focus on the different techniques that have been tested across the THz and into the mm-wave bands in both transmission and reflection imaging modes. The impact on image quality will be demonstrated, and their implications to developing useful systems for different applications will be discussed.

INO has a wide experience in the design and fabrication of different kinds of microbolometer focal plane arrays (FPAs). In particular, a 512x3 pixel microbolometer FPA has been selected as the sensor for the New Infrared Sensor Technology (NIRST) instrument, one of the payloads of the SACD/Aquarius mission. In order to make the absolute temperature measurements necessary for many infrared Earth observation applications, the microbolometer FPA must be integrated into a package offering a very stable thermal environment. The radiometric packaging technology developed at INO presents an innovative approach since it was conceived to be modular and adaptable for the packaging of different microbolometer FPAs and for different sets of assembly requirements without need for requalification of the assembly process. The development of the radiometric packaging technology has broadened the position of INO as a supplier of radiometric detector modules integrating FPAs of microbolometers inside a radiometric package capable of achieving the requirements of different space missions. This paper gives an overview of the design of INO’s radiometric package. Key performance parameters are also discussed and the test campaign conducted with the radiometric package is presented.

The adaptive optics system for the Thirty Meter Telescope (TMT) is the Narrow-Field InfraRed Adaptive Optics System (NFIRAOS). Recently, INO has been involved in the optomechanical design of several subsystems of NFIRAOS, including the instrument selection mirror (ISM), the beam splitter (NBS), and the source simulator system (NSS) comprising the focal plane mask (FPM), the laser guide star (LGS), and natural guide star (NGS) sources. This paper presents an overview of these subsystems and the optomechanical design approaches used to meet the optical performance requirements under environmental constraints., Optomechanical Engineering 2017, 9 - 10 August 2017, San Diego, California, United States

The VISTA IR Camera has now completed its detailed design phase and is on schedule for delivery to ESO's Cerro Paranal Observatory in 2006. The camera consists of 16 Raytheon VIRGO 2048×2048 HgCdTe arrays in a sparse focal plane sampling a 1.65 degree field of view. A 1.4m diameter filter wheel provides slots for 7 distinct science filters, each comprising 16 individual filter panes. The camera also provides autoguiding and curvature sensing information for the VISTA telescope, and relies on tight tolerancing to meet the demanding requirements of the f/1 telescope design. The VISTA IR camera is unusual in that it contains no cold pupil-stop, but rather relies on a series of nested cold baffles to constrain the light reaching the focal plane to the science beam. In this paper we present a complete overview of the status of the final IR Camera design, its interaction with the VISTA telescope, and a summary of the predicted performance of the system.

Field experiments conducted in 2002 and 2003 evaluated the effects of timing of inflorescence removal on propagule formation, growth and development of Astilbe ×arendsii, Hemerocallis spp. and Hosta spp. Four timings of inflorescence removal were tested: 1) no removal (control), 2) removal at inflorescence emergence, 3) removal at preflower, and 4) Removal at full flower. Propagule formation in Astilbe was not enhanced by inflorescence removal. Hemerocallis plants with their inflorescences removed at emergence produced 25% more divisions than plants with their inflorescences removed at preflower. For Hosta, plants with inflorescences removed at pre- and full flower produced respectively 40% and 53% more divisions than control plants. These results have economic implications for commercial bare-root production, which need to be verified on a larger field scale.

CCAT1 is a submillimeter telescope currently under development that will be located at an altitude of 5600 meters in the Andes mountains of northern Chile. The atmospheric transmission at this site will allow CCAT to achieve high sensitivity over a wide field of view and a broad wavelength range to provide an unprecedented capability for deep, large area multicolor submillimeter surveys. In order to achieve high aperture efficiencies out to frequencies of ~ 1 THz, the 162 individual panels that form the 25 meter aperture of CCAT must be aligned to a tolerance of a few microns rms. The design of a wavefront sensor to achieve this goal is presented.

The new high precision polarimeter for the “Observatoire du Mont Megantic” (POMM) is an instrument designed to observe exoplanets and other targets in the visible and near infrared wavebands. The requirements to achieve these observation goals are posing unusual challenges to structural and mechanical designers. In this paper, the detailed design, analysis and laboratory results of the key mechanical structure and sub-systems are presented. First, to study extremely low polarization, the birefringence effect due to stresses in the optical elements must be kept to the lowest possible values. The double-wedge Wollaston custom prism assembly that splits the incoming optical beam is made of bonded α-BBO to N-BK-7 glass lenses. Because of the large mismatch of coefficients of thermal expansion and temperatures as low as -40°C that can be encountered at Mont-Megantic observatory, a finite element analysis (FEA) model is developed to find the best adhesive system to minimize stresses. Another critical aspect discussed in details is the implementation of the cascaded rotating elements and the twin rotating stages. Special attention is given to the drive mechanism and encoding technology. The objective was to reach high absolute positional accuracy in rotation without any mechanical backlash. As for many other instruments, mass, size and dimensional stability are important critera for the supporting structure. For a cantilevered device, such as POMM, a static hexapod is an attractive solution because of the high stiffness to weight ratio. However, the mechanical analysis revealed that the specific geometry of the dual channel optical layout also added an off-axis counterbalancing problem. To reach an X-Y displacement error on the detector smaller than 35μm for 0-45° zenith angle, further structural optimization was done using FEA. An imaging camera was placed at the detector plane during assembly to measure the actual optical beam shift under varying gravitational loading.

A polarimeter, to observe exoplanets in the visible and infrared, was built for the “Observatoire du Mont Megantic” (OMM) to replace an existing instrument and reach 10-6 precision, a factor 100 improvement. The optical and mechanical designs are presented, with techniques used to precisely align the optical components and rotation axes to achieve the targeted precision. A photo-elastic modulator (PEM) and a lock-in amplifier are used to measure the polarization. The typical signal is a high DC superimposed to a very faint sinusoidal oscillation. Custom electronics was developed to measure the AC and DC amplitudes, and characterization results are presented.

Field experiments were conducted in 2002 and 2003 to evaluate the effects of selected plant growth regulators on propagule production in Hemerocallis `Happy Returns' and Hosta `Gold Standard'. Benzyladenine (BA), chlormequat chloride (Cycocel), ethephon (Ethrel), prohexadione calcium (Apogee), and an experimental preparation of commercial seaweed extract (Acadian Seaplants Limited Liquid Seaweed Concentrate) amended with BA and IBA were tested at two times of application and three rates of application. Results with Hemerocallis showed that the application of the seaweed/PGR mixture at 3000 mg·L–1, Cycocel at 3000 mg·L–1 or BA at 2500 mg·L–1 applied at flowering, increased the number of plants producing two divisions compared to control plants. In Hosta, no increase in divisions under any treatments was observed.

The image quality of a HMD apparatus composed of a camera, a data processing chain, a display and a reimaging optical element is evaluated. Its most problematic components are identified for further improvement.

Laser based video projectors (LBVP) are relatively new on the scene of video display. LBVPs consist of laser beams that are scanned and synchronously modulated. An important characteristic of the LBVP is the very short lifetime of the pixels. Each pixel produces light only for the very short time during which the laser beam passes on it. The short transients make the measurement of a LBVP image’s properties more difficult to obtain in comparison to conventional display devices. The validity of the results is even questionable when conventional methods are used to measure the characteristics of LBVP images. This paper presents an alternative method for the characterization of brightness and contrast of LBVP images that is expected to provide more reliable results.

The use of uncooled microbolometer detectors for space infrared (IR) imaging application requires high optical throughput, which leads to very fast optical design (~f/1). This directly translates into stringent requirements for components, assembly and alignment. The Institut National d'Optique (INO) in Quebec City, Canada, designed such a system for the NIRST IR Camera. The instrument is part of the Aquarius/SAC-D satellite, a cooperative mission conducted jointly by NASA and the Comision Nacional de Actividades Espaciales (CONAE) of Argentina. Due to the tight volume and mass allocation, the NIRST camera module is an all refractive design. Since the Camera is made of two lens barrels co-registered to cover the same ground area at different wavelength bands, it also adds coregistration alignment constraints. This paper presents the optomechanical solutions and alignment scheme that enabled the successful design and flight qualification. Trade-off study between thermally induced stress and structural stiffness of the lens RTV bond is discussed. Special attention is given to lens subcell alignment integrity under random vibration encountered during launch. Detailed Finite Element Analysis (FEA) is used to check early design assumptions. Test results of the final vibration campaign are also presented.

Aquarius/SAC-D is a cooperative international mission conducted jointly by the National Aeronautics and Space Administration of the United States of America and the Comision Nacional de Actividades Espaciales of Argentina. Jointly developed by CONAE and the Canadian Space Agency, the New IR Sensor Technology (NIRST) instrument will monitor high temperature events. NIRST has one band in the mid-wave infrared and two bands in the thermal infrared. The baseline design of the NIRST is based on microbolometer technology developed jointly by INO and the CSA. This paper will first present an overview of the design of the NIRST camera module. The manufacturing and qualification activities for the Flight Model will be described and key performance parameters, as measured during the verification campaign, will be reported.

INO has extensive experience in the design and fabrication of focal plane arrays (FPAs) of uncooled microbolometers. In particular, the FPA of 512×3 microbolometers, developed in collaboration with the Canadian Space Agency (CSA), has been selected for use in the NIRST (New Infrared Sensor Technology) radiometer of the SAC-D Aquarius mission. The FPA has been designed for pushbroom scanning of the Earth to provide radiometric data in the mid- and long-wave infrared for the monitoring of fires as well as thermal mapping of ocean temperature. Uncooled microbolometer detectors are suited for space applications due to their low power consumption while still exhibiting adequate performance. Furthermore, the spectral range of their response could be tuned from the mid- to the far-infrared to meet different mission requirements. In order to ensure that the detector receives only the thermal contribution from the desired target and to minimize radiometric error due to variation of the temperature of the surrounding during the measurements, a radiometric package is required. In a radiometric package the detector environment is thermally stabilized by means of a temperature controlled radiation shield. The radiation shield should also be designed to prevent stray radiation from reaching the detector. Under the Space Technology Development Program of the CSA, INO has designed, assembled and tested a radiometric package in order to characterize its performance and compatibility with the space environment. The operating spectral band is defined by the spectral characteristics of a bandpass filter placed in front of the FPA. For typical space missions, the package must pass standard environmental tests without degradation of its performance (thermal cycling from -55 to +85 °C according to MIL-STD-810, random acceleration up to 14 G RMS from 20-2000 Hz and shock up to 75 G). In order to ensure reliability in those conditions while maintaining optimum performance, an adequate selection of materials is necessary. In this paper, INO's radiometric packaging technology for uncooled microbolometer FPA's will be presented. The selection of materials will be discussed and the final choices presented based on thermal simulations and experimental data. The effects of different design parameters on the performance, such as material, shape and thickness of radiation shield and choice of adhesive have been studied. An instantaneous noise equivalent temperature difference (NETD) of ~ 20 mK was obtained under the measurement conditions (broadband LWIR, 140 ms integration time, f/1 optics, characterization in flood exposure). The design of the package reduced the contribution of environmental temperature variations on the offset of the sensor. The equivalent response of the package varied less than 0.08 °C per degree of variation of the temperature of the package. The package also showed low sensitivity to stray radiation as a result of the effectiveness of the radiation shield design. The device successfully passed the prescribed environmental tests without degradation of performance.

An Imaging Fourier Transform Spectrometer (IFTS), named FTS-2, is being developed by the University of Lethbridge for use with the SCUBA-2 sub-millimeter bolometric camera on the James Clerk Maxwell Telescope (JCMT). The FTS-2 optical model was developed and optimized in Zemax by the Institut National d'Optique (INO) to maximize the FOV and efficiency over a range of spectral resolutions. The IFTS has been designed as a folded system including corner cubes in the interferometer moving mirror, and extended polynomial surfaces in the interferometer folding mirrors. The instrument design for FTS-2 is described elsewhere; here we present an analysis of the modeled performance of the IFTS in terms of achievable Field Of View (FOV), spot pattern and vignetting, at Zero Path Difference (ZPD) and for the 2 resolution modes. The predicted imaging performance is compared to that of the SCUBA-2 camera alone.

We present the optomechanical design of a polarimeter to be used with the SCUBA-2 camera at the James-Clerk-Maxwell Telescope. The polarimeter, built to study polarized sub-millimeter radiations, has a clear aperture of 269 mm and is composed of three optical elements: a calibration polarizer, a half wave plate rotating at a speed of up to5 Hz, and an analyzer polarizer. All three elements can be placed in and out of the beam, depending on the telescope's observation mode.

Aquarius/SAC-D is a cooperative international mission conducted jointly by the National Aeronautics and Space Administration (NASA) of the United States of America (USA) and the Comision Nacional de Actividades Espaciales (CONAE) of Argentina. The overall mission targets the understanding of the total Earth system and the consequences of the natural and man-made changes in the environment of the planet. Jointly developed by CONAE and the Canadian Space Agency (CSA), the New IR Sensor Technology (NIRST) instrument will monitor high temperature events on the ground related to fires and volcanic events, and will measure their physical parameters. Furthermore, NIRST will take measurements of sea surface temperatures mainly off the coast of South America as well as other targeted opportunities. NIRST has one band in the mid-wave infrared centered at 3.8 um with a bandwidth of 0.8 um, and two bands in the thermal infrared, centered respectively at 10.85 and 11.85 um with a bandwidth of 0.9 um. The temperature range is from 300 to 600 K with an NEDT < 0.5 K for the mid-infrared band and from 200 to 400 K with an NEDT < 0.4 K for the thermal bands. The baseline design of the NIRST is based on micro-bolometer technology developed jointly by INO and the CSA. Two arrays of 512x3 uncooled bolometric sensors will be used to measure brightness temperatures. The instantaneous field-of-view is 534 microradians corresponding to a ground sampling distance of 350 m at the subsatellite point. A pointing mirror allows a total swath of +/− 500 km. This paper describes the detailed design of the NIRST camera module. Key performance parameters are also presented.

This paper describes our approach to the design of reflective, image-slicing Integral-Field Units. The first IFU built at the UK ATC (Ramsay-Howat et al 2004) has been successfully commissioned and is in routine use on the UKIRT. This IFU uses all diamond-turned optics and close attention was paid in the design to the manufacturability of the individual components, their alignment into groups and the overall alignment and integration of the IFU into the spectrometer. Building on this experience we are designing and making four IFUs for the MIRI on JWST where constraints on mass and launch survivability have led us to use monolithic arrays of slicing and re-imaging mirrors. This paper describes the ways in which the optical design and the manufacturing methods have each been adapted to: (a) achieve image quality, pupil alignment and mass requirements (b) ensure components can be reliably manufactured to the tolerances needed so that the IFUs can be aligned without adjustment and (c) ensure that performance is maintained after launch and cooling to 7 K. We also show that, although designed specifically for a space instrument, such a compact and reproducible IFU is well suited to instruments where multiple IFUs are required.

As detailed instrument design progresses, judgements have to be made as to what changes to allow and when models such as thermal, stray-light and mechanical structure analysis have to be re-run. Starting from a well-founded preliminary design, and using good engineering design when incorporating changes, the design detailing and re-run of the models should bring no surprises. Nevertheless there are issues for maintaining the design and model configuration to a reasonably concurrent level. Using modern modeling software packages and foresight in setting up the models the process is made efficient, but at the same time the level of detail and number of cases now needed for instrument reviews is also large in order to minimise risks. We describe examples from the detailed instrument design of the VISTA IR Camera to illustrate these aspects and outline the design and analysis methods used.

VISTA is a 4m class survey telescope designed to perform pre-planned, ground-based astronomy surveys of the Southern sky in the visible and infrared spectrum. The telescope includes a Cassegrain mounted infrared (IR) camera with a field of view of 1.65 degrees. The camera has no cold stop, and therefore the three lenses constituting the field corrector are positioned inside the cryostat of the camera. A window of 950mm diameter closes the cryostat. The lenses have a diameter of approximately 600 mm, and the third lens have its first surface with an aspheric profile. The large cryostat window and the aspheric surface of the third lens are the most difficult components to manufacture and test. To our knowledge, they are the largest Infrasil 302 components to be mounted and used inside a cryostat at 100K up to this date.

Uncooled microbolometer detectors are well suited for space applications due to their low power consumption while still exhibiting adequate performance. Furthermore, the spectral range of their response could be tuned from the mid- to the far-infrared to meet different mission requirements. If radiometric measurements are required, the radiometric error induced by variation of the temperature of the detector environment must be minimized. In a radiometric package, the detector environment is thermally stabilized by means of a temperature-controlled radiation shield. The radiation shield must be designed to prevent stray radiation from reaching the detector. A radiometric packaging technology for uncooled microbolometer FPAs is presented. The selection of materials is discussed and the final choices presented based on thermal simulations and experimental data. The radiometric stability with respect to stray light and variation of the temperature of the environment as well as the different noise components studied by means of the Allan variance are presented. It is also shown that the device successfully passed the prescribed environmental tests without degradation of performance.