Optimization of the Mechanical and Optical Properties of Tunable Optical Sensor Arrays (TOSA) for a Nanospectrometer in the Visible and Near Infrared Spectral Range

Tunable Optical Sensor Arrays (TOSA) based on Fabry-Pérot (FP) filters, for high quality spectroscopic applications in the visible and near infrared spectral range are investigated within this work. The optical performance of the FP filters is improved by using ion beam sputtered niobium pentoxide (Nb2O5) and silicon dioxide (SiO2) Distributed Bragg Reflectors (DBRs) as mirrors. Due to their high refractive index contrast, only a few alternating pairs of Nb2O5 and SiO2 films can achieve DBRs with high reflectivity in a wide spectral range, while ion beam sputter deposition (IBSD) is utilized due to its ability to produce films with high optical purity. However, IBSD films are highly stressed; resulting in stress induced mirror curvature and suspension bending in the free standing filter suspensions of the MEMS (Micro-Electro-Mechanical Systems) FP filters. Stress induced mirror curvature results in filter transmission line degradation, while suspension bending results in high required filter tuning voltages. Moreover, stress induced suspension bending results in higher order mode filter operation which in turn degrades the optical resolution of the filter. Therefore, the deposition process is optimized to achieve both near zero absorption and low residual stress. High energy ion bombardment during film deposition is utilized to reduce the film density, and hence the film compressive stress. Utilizing this technique, the compressive stress of Nb2O5 is reduced by ~43%, while that for SiO2 is reduced by ~40%. Filters fabricated with stress reduced films show curvatures as low as 100 nm for 70 μm mirrors. To reduce the stress induced bending in the free standing filter suspensions, a stress optimized multi-layer suspension design is presented; with a tensile stressed metal sandwiched between two compressively stressed films. The stress in Physical Vapor Deposited (PVD) metals is therefore characterized for use as filter top-electrode and stress compensating layer. Surface micromachining is used to fabricate tunable FP filters in the visible spectral range using the above mentioned design. The upward bending of the suspensions is reduced from several micrometers to less than 100 nm and 250 nm for two different suspension layer combinations. Mechanical tuning of up to 188 nm is obtained by applying 40 V of actuation voltage. Alternatively, a filter line with transmission of 65.5%, Full Width at Half Maximum (FWHM) of 10.5 nm and a stopband of 170 nm (at an output wavelength of 594 nm) is achieved. Numerical model simulations are also performed to study the validity of the stress optimized suspension design for the near infrared spectral range, wherein membrane displacement and suspension deformation due to material residual stress is studied. Two bandpass filter designs based on quarter-wave and non-quarter-wave layers are presented as integral components of the TOSA. With a filter passband of 135 nm and a broad stopband of over 650 nm, high average filter transmission of 88% is achieved inside the passband, while maximum filter transmission of less than 1.6% outside the passband is achieved.

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Cap mòbil amb tecnologia led RGBW controlat per DMX

Disseny tant a nivell de hardware com de software d’un cap mòbil amb tecnologia led RGBW controlat pel protocol DMX512. Aquest projecte es limita al disseny i a la realització de tots els elements de software i hardware necessaris per crear un prototipus de cap mòbil que pugui ser controlat mitjançant el protocol DMX. Per tant, està encarat completament cap a la vessant electrònica i de programació sense fer referència als materials i elements constructius utilitzats o sobre el disseny i estètica del producte

The Intrapreneur Innovation:Led by Medium and Small Size Companies‘Managers*(Qualitative Research)

This research is focused on an exploratory study developed with Pymes managers and theirroles as intrapreneurs. Using their leadership to impel innovation into organizations.Looking to determined how Pymes employers incentive into organizations individuals or groupinnovations. Therefore, it is possible to think that managers lead the innovation process, whichis classified gradually according to companies needs in order to improve their competitiveness.Organization must have intrapreneuring and organized culture with flexible structure to generateindividual autonomy. A characteristic is the amount of capital risk needed; that is why it isnecessary encourage their work and their risk tolerance.

Edexcel A2 biology revision guide : for SNAB and concept-led approaches.

Guía para la revisión de los recursos Edexcel para la especificación General Certificate of Education (GCE ) Biología. Salters Nuffield Advanced Biology es el material de apoyo oficial. Curso completo diseñado para mostrar a los estudiantes cómo la comprensión de muchos problemas contemporáneos requiere de un conocimiento fundamental de las ideas biológicas. Favorece el aprendizaje autónomo de una amplia gama de conocimientos, incluidos el análisis de datos, evaluación crítica de información, comunicación y trabajo cooperativo. Se basa en datos de exámenes reales para ayudar a los estudiantes a evitar errores habituales y construir mejores respuestas. Los ejemplos de preguntas de examen incluyen las de opción múltiple. Tiene las soluciones a las preguntas del texto.

Edexcel AS biology revision guide : for SNAB and concept-led approaches.

Guía para la revisión de los recursos Edexcel para la especificación General Certificate of Education (GCE ) Biología. Salters Nuffield Advanced Biology es el material de apoyo oficial. Curso completo diseñado para mostrar a los estudiantes cómo la comprensión de muchos problemas contemporáneos requiere de un conocimiento fundamental de las ideas biológicas. Favorece el aprendizaje autónomo de una amplia gama de conocimientos, incluidos el análisis de datos, evaluación crítica de información, comunicación y trabajo cooperativo. Se basa en datos de exámenes reales para ayudar a los estudiantes a evitar errores habituales y construir mejores respuestas. Los ejemplos de preguntas de examen incluyen las de opción múltiple. Tiene las soluciones a las preguntas del texto.

Edexcel AS physics revision guide : for SHAP and concept-led approaches.

Guía para la revisión de los recursos Edexcel para la especificación General Certificate of Education (GCE ) Física. Salters-Horners Advanced Physics (SHAP) es el material de apoyo oficial. Es un curso completo que cubre la física a través de los contextos de la vida real, que combina los conceptos clave que sustenta la física, con la oportunidad de adquirir las habilidades que los físicos necesitan hoy. Favorece el aprendizaje autónomo y construye una amplia gama de conocimientos, incluidos el análisis de datos, evaluación crítica de información, comunicación y trabajo cooperativo. Se basa en datos de exámenes reales para ayudar a los estudiantes a evitar errores habituales y construir mejores respuestas. Los ejemplos de preguntas de examen incluyen las de opción múltiple. Tiene las soluciones a las preguntas del texto.

Edexcel A2 physics revision guide : for SHAP and concept-led approaches.

Guía para la revisión de los recursos Edexcel para la especificación General Certificate of Education (GCE ) Física. Salters-Horners Advanced Physics (SHAP) es el material de apoyo oficial. Es un curso completo que cubre la física a través de los contextos de la vida real, que combina los conceptos clave que sustenta la física, con la oportunidad de adquirir las habilidades que los físicos necesitan hoy. Favorece el aprendizaje autónomo con una amplia gama de conocimientos, incluidos el análisis de datos, evaluación crítica de información, comunicación y trabajo cooperativo. Se basa en datos de exámenes reales para ayudar a los estudiantes a evitar errores habituales y construir mejores respuestas. Los ejemplos de preguntas de examen incluyen las de opción múltiple. Tiene las soluciones a las preguntas del texto.

An improved algorithm for generating global window brightness temperatures from multiple satellite infrared imagery

An improved algorithm for the generation of gridded window brightness temperatures is presented. The primary data source is the International Satellite Cloud Climatology Project, level B3 data, covering the period from July 1983 to the present. The algorithm rakes window brightness, temperatures from multiple satellites, both geostationary and polar orbiting, which have already been navigated and normalized radiometrically to the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer, and generates 3-hourly global images on a 0.5 degrees by 0.5 degrees latitude-longitude grid. The gridding uses a hierarchical scheme based on spherical kernel estimators. As part of the gridding procedure, the geostationary data are corrected for limb effects using a simple empirical correction to the radiances, from which the corrected temperatures are computed. This is in addition to the application of satellite zenith angle weighting to downweight limb pixels in preference to nearer-nadir pixels. The polar orbiter data are windowed on the target time with temporal weighting to account for the noncontemporaneous nature of the data. Large regions of missing data are interpolated from adjacent processed images using a form of motion compensated interpolation based on the estimation of motion vectors using an hierarchical block matching scheme. Examples are shown of the various stages in the process. Also shown are examples of the usefulness of this type of data in GCM validation.

Cooled Infrared Dichroic Beamsplitters and Filters for the MIRI Spectrometer and Imager (5-29µm)

The spectral design and fabrication of cooled (7K) mid-infrared dichroic beamsplitters and bandpass filter coatings for the MIRI spectrometer and imager are described. Design methods to achieve the spectral performance and coating materials are discussed.

Mid-infrared filters for astronomical and remote sensing instrumentation

As improvements to the optical design of spectrometer and radiometer instruments evolve with advances in detector sensitivity, use of focal plane detector arrays and innovations in adaptive optics for large high altitude telescopes, interest in mid-infrared astronomy and remote sensing applications have been areas of progressive research in recent years. This research has promoted a number of developments in infrared coating performance, particularly by placing increased demands on the spectral imaging requirements of filters to precisely isolate radiation between discrete wavebands and improve photometric accuracy. The spectral design and construction of multilayer filters to accommodate these developments has subsequently been an area of challenging thin-film research, to achieve high spectral positioning accuracy, environmental durability and aging stability at cryogenic temperatures, whilst maximizing the far-infrared performance. In this paper we examine the design and fabrication of interference filters in instruments that utilize the mid-infrared N-band (6-15 µm) and Q-band (16-28 µm) atmospheric windows, together with a rationale for the selection of materials, deposition process, spectral measurements and assessment of environmental durability performance.

Assessment of the consistency of near-infrared water vapor line intensities using high-spectral-resolution ground-based Fourier transform measurements of solar radiation

Calculations of the absorption of solar radiation by atmospheric gases, and water vapor in particular, are dependent on the quality of databases of spectral line parameters. There has been increasing scrutiny of databases such as HITRAN in recent years, but this has mostly been performed on a band-by-band basis. We report nine high-spectral-resolution (0.03 cm(-1)) measurements of the solar radiation reaching the surface in southern England over the wave number range 2000 to 12,500 cm(-1) (0.8 to 5 mm) that allow a unique assessment of the consistency of the spectral line databases over this entire spectral region. The data are assessed in terms of the modeled water vapor column that is required to bring calculations and observations into agreement; for an entirely consistent database, this water vapor column should be constant with frequency. For the HITRAN01 database, the spread in water vapor column is about 11%, with distinct shifts between different spectral regions. The HITRAN04 database is in significantly better agreement (about 5% spread) in the completely updated 3000 to 8000 cm(-1) spectral region, but inconsistencies between individual spectral regions remain: for example, in the 8000 to 9500 cm(-1) spectral region, the results indicate an 18% (+/- 1%) underestimate in line intensities with respect to the 3000 to 8000 cm(-1) region. These measurements also indicate the impact of isotopic fractionation of water vapor in the 2500 to 2900 cm(-1) range, where HDO lines dominate over the lines of the most abundant isotope of H2O.