Applet de Física. Polarización lineal: Ley de Malus.

Quan un feix de llum incideix sobre un conjunt de dos o més polaritzadors lineals la intensitat transmesa, que depèn de l'angle relatiu entre ells, es pot expressar mitjançant la llei de Malus. En aquesta simulació es pot veure l'efecte sobre la intensitat del feix incident de l'actuació d'un, dos i fins a tres polaritzadors lineals, dels quals podem seleccionar el seu nombre i variar l'orientació del seu eix de transmissió, comprovant d'aquesta manera el compliment de la llei de Malus.Cuando un haz de luz incide sobre un conjunto de dos o más polarizadores lineales la intensidad transmitida, que depende del ángulo relativo entre ellos, se puede expresar mediante la ley de Malus. En esta simulación se puede ver el efecto sobre la intensidad incidente de la actuación de uno, dos y hasta tres polarizadores lineales, de los que podemos seleccionar su número y variar la orientación de su eje de transmisión, comprobando de este modo el cumplimiento de la ley de Malus.When a light beam impinges on a set of two or more linear polarizers the transmitted intensity, which depends on the relative angle between them, can be expressed by Malus’law. In this simulation is possible to see the effect of one, two or three linear polarizers on the incident light beam intensity. We can select the number of polarizers and the orientation of its transmission axis, thereby checking the fulfillment of Malus’law

Demo 23. Interferencias y difracción con luz

Objetivo: Mostrar el comportamiento ondulatorio de la luz, mediante los fenómenos de difracción e interferencias. Determinar la longitud de onda de la luz emitida por un láser, midiendo exclusivamente distancias de escala macroscópica

Demo 24. Maleta de óptica geométrica con soporte magnético

Objetivo: Comprobar las leyes de la refracción y de la reflexión. Visualizar la trayectoria de los rayos de luz en diversos elementos ópticos tales como lentes, prismas y espejos, planos o esféricos, así como en instrumentos ópticos sencillos

Demo 43. Espejos esféricos

Objetivo: Obtener una imagen real por reflexión doble en dos espejos esféricos de idéntico radio de curvatura

Toward 3D integral-imaging broadcast with increased viewing angle and parallax

We propose a new method for improving the observer experience when using an integral monitor. Our method permits to increase the viewing angle of the integral monitor, and also the maximum parallax that can be displayed. Additionally, it is possible to decide which parts of the 3D scene are displayed in front or behind the monitor. Our method is based, first, in the direct capture, with significant excess of parallax, of elemental images of 3D real scenes. From them, a collection of microimages adapted to the observer lateral and depth position is calculated. Finally, an eye-tracking system permits to determine the 3D observer position, and therefore to display the adequate microimages set. Summarizing, it is reported here, for the first time we believe, the application of eye-tracking technology to the display of integral images of 3D real scenes with bright background. Although we are reporting here only a proof-of-concept experiment, this result could have direct application in a close future for the broadcasting of 3D videos recorded in professional studio, for videoconferences or for on-line professional meetings

Recent advances in the capture and display of macroscopic and microscopic 3-D scenes by integral imaging

The capture and display of images of 3-D scenes under incoherent and polychromatic illumination is currently a hot topic of research, due to its broad applications in bioimaging, industrial procedures, military and surveillance, and even in the entertainment industry. In this context, Integral Imaging (InI) is a very competitive technology due to its capacity for recording with a single exposure the spatial-angular information of light-rays emitted by the 3-D scene. From this information, it is possible to calculate and display a collection of horizontal and vertical perspectives with high depth of field. It is also possible to calculate the irradiance of the original scene at different depths, even when these planes are partially occluded or even immersed in a scattering medium. In this paper, we describe the fundaments of InI and the main contributions to its development. We also focus our attention on the recent advances of the InI technique. Specifically, the application of InI concept to microscopy is analyzed and the achievements in resolution and depth of field are explained. In a different context, we also present the recent advances in the capture of large scenes. The progresses in the algorithms for the calculation of displayable 3-D images and in the implementation of setups for the 3-D displays are reviewed

Handheld and cost-effective Fourier lightfield microscope

In this work, the design, building, and testing of the most portable, easy-to-build, robust, handheld, and cost-effective Fourier Lightfield Microscope (FLMic) to date is reported. The FLMic is built by means of a surveillance camera lens and additional off-the-shelf optical elements, resulting in a cost-effective FLMic exhibiting all the regular sought features in lightfield microscopy, such as refocusing and gathering 3D information of samples by means of a single-shot approach. The proposed FLMic features reduced dimensions and light weight, which, combined with its low cost, turn the presented FLMic into a strong candidate for in-field application where 3D imaging capabilities are pursued. The use of cost-effective optical elements has a relatively low impact on the optical performance, regarding the figures dictated by the theory, while its price can be at least 100 times lower than that of a regular FLMic. The system operability is tested in both bright-field and fluorescent modes by imaging a resolution target, a honeybee wing, and a knot of dyed cotton fibers

Integral imaging with Fourier-plane recording

Integral Imaging is well known for its capability of recording both the spatial and the angular information of threedimensional (3D) scenes. Based on such an idea, the plenoptic concept has been developed in the past two decades, and therefore a new camera has been designed with the capacity of capturing the spatial-angular information with a single sensor and after a single shot. However, the classical plenoptic design presents two drawbacks, one is the oblique recording made by external microlenses. Other is loss of information due to diffraction effects. In this contribution report a change in the paradigm and propose the combination of telecentric architecture and Fourier-plane recording. This new capture geometry permits substantial improvements in resolution, depth of field and computation time

Applet de Física. Interferencias de dos haces luminosos. Biprisma de Fresnel.

El biprisma de Fresnel es un dispositivo interferencial constituido por dos prismas delgados unidos por sus bases. Cuando el biprisma se ilumina con una fuente puntual monocromática se obtiene un patrón de interferencias, por división del frente de ondas, similar al observado en el experimento clásico de la doble rendija de Young. En esta simulación se puede analizar la dependencia de la interfranja del patrón interferencial con difrentes parámetros tales como: características del biprisma (índice de refracción y ángulo de refringencia), posición axial del biprisma y distancia a la que se encuentra la pantalla de observación.The Fresnel biprism is an interferential device comprising two thin prisms joined at their bases. When the biprism is illuminated with a monochromatic point source, a interference pattern is obtained by wavefront division, similar to that observed in the classic Young's double slit experiment. In this simulation you can analyze the dependence of the interference pattern with diferent parameters such as biprism characteristics (refractive index and angle of refraction), axial position and distance from the observation screen