Iluminando con LEDs

En este trabajo se analizan las posibilidades de la tecnología de iluminación LED, comparándola con otras tecnologías como la lámpara halógena o la fluorescente. Se tratan aspectos clave como el rendimiento luminoso, el ahorro energético y la duración de las lámparas. Al mismo tiempo se introducen apuntes históricos del desarrollo de las tecnologías de iluminación que permiten una visión global y una reflexión sobre el futuro

Determinación de las constantes ópticas y el espesor de materiales de registro holográfico

Este trabajo ha sido subvencionado por la CICYT (proyecto MAT2000-1361-C04-04) y la Oficina de Ciencia y Tecnología de la Generalitat Valenciana (proyecto GV01-130)

Performance analysis of SSE and AVX instructions in multi-core CPUs and GPU computing on FDTD scheme for solid and fluid vibration problems

In this work a unified treatment of solid and fluid vibration problems is developed by means of the Finite-Difference Time-Domain (FDTD). The scheme here proposed takes advantage from a scaling factor in the velocity fields that improves the performance of the method and the vibration analysis in heterogenous media. Moreover, the scheme has been extended in order to simulate both the propagation in porous media and the lossy solid materials. In order to accurately reproduce the interaction of fluids and solids in FDTD both time and spatial resolutions must be reduced compared with the set up used in acoustic FDTD problems. This aspect implies the use of bigger grids and hence more time and memory resources. For reducing the time simulation costs, FDTD code has been adapted in order to exploit the resources available in modern parallel architectures. For CPUs the implicit usage of the advanced vectorial extensions (AVX) in multi-core CPUs has been considered. In addition, the computation has been distributed along the different cores available by means of OpenMP directives. Graphic Processing Units have been also considered and the degree of improvement achieved by means of this parallel architecture has been compared with the highly-tuned CPU scheme by means of the relative speed up. The speed up obtained by the parallel versions implemented were up to 3 (AVX and OpenMP) and 40 (CUDA) times faster than the best sequential version for CPU that also uses OpenMP with auto-vectorization techniques, but non includes implicitely vectorial instructions. Results obtained with both parallel approaches demonstrate that massive parallel programming techniques are mandatory in solid-vibration problems with FDTD.The work is partially supported by the “Ministerio de Economía y Competitividad” of Spain under project FIS2011-29803-C02-01, by the Spanish Ministry of Education (TIN2012-34557), by the “Generalitat Valenciana” of Spain under projects PROMETEO/2011/021 and ISIC/2012/013, and by the “Universidad de Alicante” of Spain under project GRE12-14

Polymerizable Materials for Diffractive Optical Elements Recording

The technologies based on holographic and photonic techniques related to the optical storage and optical processing of information are rapidly evolving. One of the key points of this evolution are the new recording materials able to perform under the most specific situations and applications. In this sense, the importance of the photopolymers is growing spectacularly. This is mainly due to their versatility in terms of composition and design together with other interesting properties such as self-processing capabilities. In this chapter, we introduce the diffractive optical elements (DOE) generation in these materials and some of the most important parameters involved in this process. The deep knowledge of the material is essential to model its behavior during and after the recording process and we present different techniques to characterize the recording materials. We also present a 3D theoretical diffusion model able to reproduce and predict the experimental behavior of the recording process of any kind of DOE onto the photopolymers. The theoretical results will be supported by experimental analysis using a hybrid optical-digital setup, which includes a liquid crystal on silicon display. Besides this analysis, we study a method to improve the conservation and characteristics of these materials, an index-matching system

Holographic Data Storage Using Parallel-Aligned Liquid Crystal on Silicon Displays

The parallel-aligned liquid crystal on silicon (PA-LCoS) microdisplay has become a widely used device for the photonics community. It is a very versatile tool that can perform several tasks which transforms it into a key element in many different photonics applications. Since our group is interested in holography, in this chapter, we want to use these displays as the data entry point for a holographic data storage system (HDSS). Due to the novelty of this kind of device, we have done an intense work characterizing it. These efforts are reflected in this chapter where the reader will find two different characterization methods that will enable to predict the performance of the device in a specific application. Additionally, we present how a phase-only device can be used as a data pager using different modulation schemes and combined with a photopolymer as the holographic recording material

Análisis de la acción tutorial en ingeniería y arquitectura. Gestión eficaz del tiempo

En este trabajo expondremos un análisis exhaustivo de como se ha desarrollado la acción tutorial en la Escuela Politécnica Superior de la Universidad de Alicante en el curso 2014/2015. El marcado carácter de voluntariedad de la acción tutorial en nuestro centro por parte de estudiantes y tutores permite que el trabajo se realice más satisfactoriamente tanto por parte de tutores como por parte de los estudiantes, puesto que han decidido seguir el plan por ello mismos y no como una imposición. Además expondremos nuestras experiencias en el desarrollo del Taller de Gestión Eficaz del Tiempo, taller desarrollado en nuestro centro bajo la tutela de la experta Nuria Alberquilla, que tiene entre otros muchos objetivos el aprendizaje y puesta en práctica de técnicas para realizar una gestión eficaz del tiempo, con un mejor equilibrio entre la vida académica y personal y la identificación de los principales factores externos e internos que influyen en los resultados obtenidos, y cómo mejorarlos

Holographic behavior model of polyvinylalcohol/acrylamide based photopolymer

Agradecimientos: A Cristian Neipp López e Inmaculada Pascual Villalobos, directores de la Tesis Doctoral, por sus consejos, explicaciones y ánimos.Se presentan diversos modelos y algoritmos para caracterizar el comportamiento de un fotopolímero como material de registro holográfico. Dicha caracterización se realiza principalmente mediante el registro de redes holográficas en el material. Por un lado se estudia la propagación de la luz dentro de las estructuras periódicas almacenadas y por otro la formación del holograma en el material. Para constatar la validez de los modelos propuestos se presentandiversos experimentos realizados con un fotopolímero basado en polivinilalcohol/archilamida.In order to characterize the behavior of photopolymers as holographic recording material some models and algorithms are presented. Holographic gratings with different spatial frequencies are recorded to characterize the material. The research has two main goals, the study of the light propagation inside periodic structures recorded in the materials and the modeling of the hologram formation in photopolymers. To check experimentally the models and algorithms proposed we use a polyvinylalcohol/acrylamide based photopolymer.Este trabajo ha sido subvencionado por los Ministerios de Ciencia y Tecnología y de Educación y Ciencia del Estado Español (proyectos MAT2000-1361-C04-04, MAT2004-04881-C02-01 y FIS2005-05881-C02-02)

Quadern de fonaments físics de la informàtica

Es un quadern en Valencià per assolir les competències de l'Assignatura de Fonaments Físics de la Informàtica (teoría, problemes i laboratori).Servei de Promoció del Valenci

Advances in novel optical materials and devices

Editorial of Advances in Novel Optical Materials and Devices

Diffractive and interferometric methods to characterize photopolymers with crystal liquid molecules as holographic recording material

We present two methods, interferometry at the zero spatial frequency limit and analysis of diffracted orders for very low spatial frequency gratings, to characterize photopolymers with dispersed nematic liquid crystals. These methods provide us information in real time about the transformations taking place inside the material during recording.This work was supported by the "Ministerio de Economía y Competitividad" of Spain under projects FIS2011-29803-C02-01 and FIS2011-29803-C02-02 and by the "Generalitat Valenciana" of Spain under project PROMETEO/2011/021