Wide-angle, high-extinction-ratio, infrared polarizing beam splitters using frustrated total internal reflection by an embedded centrosymmetric multilayer

A centrosymmetric multilayer stack of two transparent thin-film materials, which is embedded in a high-index prism, is designed to function as an efficient polarizer or polarizing beam splitter (PBS) under conditions of frustrated total internal reflection over an extended range of incidence angles. The S(LH)kLHL(HL)kS multilayer structure consists of a high-index center layer H sandwiched between two identical low-index films L and high-index-low-index bilayers repeated (k times) on both sides of the central trilayer maintaining the symmetry of the entire stack. For a given set of refractive indices, all possible solutions for the thicknesses of the layers that suppress the reflection of p-polarized light at a specified angle, and the associated reflectance of the system for the orthogonal s polarization, are determined. The angular and spectral sensitivities of polarizing multilayer stacks employing 3, 7, 11, 15, and 19 layers of BaF2 and PbTe thin films embedded in a ZnS prism, operating at λ=10.6 μm, are presented. The 15- and 19-layer stack designs achieve extinction ratios (ER) \u3e30 dB in both reflection and transmission over a 46°-56° field of view inside the prism. Spectral analysis reveals additional discrete polarizing wavelengths other than the design wavelength (λ=10.6 μm). The 11-, 15-, and 19-layer designs function as effective s-reflection polarizers (|Rs|2\u3e99%) over a 2-3 μm bandwidth. The effect of decreasing the refractive index contrast between the H and L layers on the resulting ER is also considered

Embedded centrosymmetric multilayer stacks as complete-transmission quarter-wave and half-wave retarders under conditions of frustrated total internal reflection

A centrosymmetric multilayer stack of two transparent materials, which is embedded in a high-index prism, can function as a complete-transmission quarter-wave or half-wave retarder (QWR or HWR) under conditions of frustrated total internal reflection. The multilayer consists of a high-index center layer sandwiched between two identical low-index films with high-index–low-index bilayers repeated on both sides of the central trilayer, maintaining the symmetry of the entire stack and constituting a QWR ( Δt=90° or 270°) or HWR (Δt=180°) in transmission. A QWR design at wavelengthλ=1.55 μm is presented that employs an 11-layer stack of Si and SiO2 thin films, which is embedded in a GaP cube prism. The intensity transmittances for the p and s polarizations remain \u3e99% and Δt deviates from 90° by \u3c±3°over a 100 nm spectral bandwidth (1.5⩽λ⩽1.6 μm) , and by ⩽±7° over an internal field view of ±1°(incidence angle 44°⩽ϕ0⩽46° inside the prism). An HWR design at λ=1.55 μm employs seven layers of Si andSiO2 thin films embedded in a Si cube, has an average transmittance \u3e93% , and Δt that differs from 180° by\u3c±0.3° over a 100 nm bandwidth (1.5⩽λ⩽1.6 μm) and by \u3c±17° over an internal field view of ±1° . The sensitivity of these devices to film-thickness errors is also considered

Polarizing properties of embedded symmetric trilayer stacks under conditions of frustrated total internal reflection

An all-transparent symmetric trilayer structure, which consists of a high-index center layer coated on both sides by a low-index film and embedded in a high-index prism, can function as an efficient polarizer or polarizing beam splitter under conditions of frustrated total internal reflection over a wide range of incidence angles. For a given set of refractive indices, all possible solutions for the thicknesses of the layers that suppress the reflection of either the p or s polarization at a specified angle, as well as the reflectance of the system for the orthogonal polarization, are determined. A 633 nm design that uses a MgF2-ZnS-MgF2 trilayer embedded in a ZnS prism achieves an extinction ratio (ER)\u3e40 dB from 50° to 80° in reflection and an ER\u3e20 dB from 58° to 80° in transmission. IR polarizers that use CaF2-Ge-CaF2 trilayers embedded in a ZnS prism are also considered

Polarizing properties of embedded symmetric trilayer stacks under conditions of frustrated total internal reflection

An error in the application of the design procedure described in a previous paper [Appl. Opt. 45, 1650 (2006)] has been corrected, and new revised figures are included in this erratum

Polarizing properties of embedded symmetric trilayer stacks under conditions of frustrated total internal reflection

An all-transparent symmetric trilayer structure, which consists of a high-index center layer coated on both sides by a low-index film and embedded in a high-index prism, can function as an efficient polarizer or polarizing beam splitter under conditions of frustrated total internal reflection over a wide range of incidence angles. For a given set of refractive indices, all possible solutions for the thicknesses of the layers that suppress the reflection of either the p or s polarization at a specified angle, as well as the reflectance of the system for the orthogonal polarization, are determined. A 633 nm design that uses a MgF2-ZnS-MgF2 trilayer embedded in a ZnS prism achieves an extinction ratio (ER)\u3e40 dB from 50° to 80° in reflection and an ER\u3e20 dB from 58° to 80° in transmission. IR polarizers that use CaF2-Ge-CaF2 trilayers embedded in a ZnS prism are also considered

Polarizing properties of embedded symmetric trilayer stacks under conditions of frustrated total internal reflection

An error in the application of the design procedure described in a previous paper [Appl. Opt. 45, 1650 (2006)] has been corrected, and new revised figures are included in this erratum

Continental Santa Anita, Tlajomulco de Zúñiga

En el reporte PAP se plasma todo el proceso que se planteó y llevo a cabo, para lograr la realización del proyecto PAP en la empresa huésped. Se manejó el proyecto con Project managment, para determinar todas las fases del proyecto, los alcances esperados con los entregables, los tiempos y finalmente obtener los resultados en los tiempos estimados. En este documento, se desglosa por capítulos, donde se toman en cuenta los tópicos principales para la explicación del desarrollo del proyecto, siempre mencionando los aspectos superficiales del proyecto a cumplir, cuidando la confidencialidad de la empresa huésped.ITESO, A.C

Acacia Horrida (L.) Willd.: refugio de artrópodos benéficos en la costa peruana

El huarango (Acacia horrida (L.) Willd., 1806) es una leguminosa arbustiva utilizada como cerco vivo en áreas agrícolas para prevenir la erosión, mejorar la nutrición del suelo y servir, además, como refugio para artrópodos benéficos, contribuyendo así a la sostenibilidad de los agroecosistemas productivos. Por ello, se quiso conocer las especies de artrópodos benéficos asociados a A. horrida en agroecosistemas de la costa centro y sur del Perú. Para ello, se colectó especímenes en cercos vivos de A. horrida cercanos a cultivos de hortalizas de La Molina (Lima), campos de mandarina y palto en Cañete (Lima) y huertos caseros con camote y frutales en Los Aquijes (Ica). Los resultados obtenidos permitieron encontrar en La Molina arañas Salticidae y Argiope sp., insectos depredadores como Harmonia axyridis Pallas, 1773, Cycloneda sanguinea Linnaeus, 1743, Scymnus rubicundus Erichson, 1847 y parasitoides del género Bracon. En Cañete se encontró la araña Gasteracantha cancriformis Linnaeus, 1758, insectos depredadores como C. sanguinea, S. rubicundus, Ceraeochrysa cincta (Schneider, 1851), Allograpta sp., Tachycompilus sp., y parasitoides como Venturia sp., Campoletis sp. Anomalon sinuatum Morley, 1912, subfamilias Cryptinae, Campopleginae (Ichneumonidae), Braconinae, Microgastrinae, Opiinae (Braconidae) y la familia Eulophidae. En Los Aquijes se encontró C. sanguinea, Hippodamia convergens Guérin-Méneville, 1842, Polistes sp. y parasitodes del género Bracon, siendo estos últimos depredados por arañas de la familia Thomisidae. Se concluye que al menos 22 taxa de artrópodos benéficos están asociados a A. horrida como refugio