The simultaneous multiple surface (SMS) method in 3-D geometry is presented. Given two orthotomic input ray bundles and another output bundles, the provides an optical system with free-form surfaces that deflects rays of into corresponding vice versa. In nonimaging applications, enables controlling light emitted by extended source much better than single free-form-surface designs, also optics contour to be shaped without efficiency losses. expected find applications imaging optics.

In order to achieve competitive system costs in mass-production, it is essential that CPV concentrators incorporate sufficient manufacturing tolerances. This paper presents an advanced concentrator optic comprising a Fresnel lens and refractive secondary element, both with broken rotational symmetry, producing the desired light concentration high tolerance (high acceptance angle) as well excellent homogenization by Köhler integration. compares conventional Fresnel-based concentrators.

By having a single optical element combine the light of several high luminance LEDs, source can be formed, with shape and emission characteristics adaptable to nearly all illumination problems. The illuminance distribution this virtual facilitates generation desired intensity pattern via its imaging-stye projection into far field. This is achieved by one refractive reflective freeform surface, both calculated simultaneously 3D SMS method, which herein demonstrated for an LED automotive headlamp.

There are great concerns about degradation of agricultural soils. It has been suggested that cultivating different plant species intercropped with coffee plants can increase microbial diversity and enhance soil sustainability. The objective this study was to evaluate enzyme activity (urease, arylsulfatase phosphatase) alterations in C N mineralization rates as related legume cover crops planted between rows plants. Soil samples were collected a field experiment conducted for 10 years sandy...

So far, illumination optics design for extended sources (like LEDs) has been mainly treated as perturbations of ideal point without any extent. Such approaches work well provided that this case is approximately met. However, the demand very compact luminaires equipped with modern high-brightness LEDs results in configurations where actual size cannot be ignored. Here, we develop a “wavefront tailoring” method producing prescribed patterns while fully encompassing source size. We combine...

In this work, we present a multifield direct design method for ultrashort throw ratio projection optics. The allows us to directly calculate two freeform mirror profiles, which are fitted by odd polynomials and imported into an optical program as excellent starting point. Afterward, these mirrors represented XY polynomial surfaces further optimization. final configuration consists of off-the-shelf lens greatly shorten the regular distance from 2 m 48 cm 78.3 inch diagonal screen. values...

The Simultaneous Multiple Surfaces design method (SMS), proprietary technology of Light Prescription Innovators (LPI), was developed in the early 1990's as a two dimensional method. first embodiments had either linear or rotational symmetry and found applications photovoltaic concentrators, illumination optics optical communications. SMS designed devices perform close to thermodynamic limit are compact simple; features that especially beneficial with today's high brightness LEDs. extended 3D...

Concentration photovoltaic (CPV) systems might produce quite uneven irradiance distributions (both on their level and spectral distribution) the solar cell. This effect can be even more evident when CPV system is slightly off-axis, since they are often designed to assure good uniformity only at normal incidence. The non-uniformities both in absolute content produced by systems, originate electrical losses multi-junction cells (MJSC). works focused integration of ray-tracing methods for...

Multi-chip and large size LEDs dominate the lighting market in developed countries these days. Nevertheless, a general optical design method to create prescribed intensity patterns for this type of extended sources does not exist. We present strategy which source target pattern are described by means "edge wavefronts" system. The goal is then finding an optic coupling wavefronts, current work monolithic part comprising up three freeform surfaces calculated with simultaneous multiple surface...

Most cost-effective concentrated photovoltaics (CPV) systems are based on an optical train comprising two stages, the first being a Fresnel lens. Among them, Fresnel-Köhler (FK) concentrator stands out owing to both performance and practical reasons. We describe experimental measurements procedure for FK modules. This includes three main types of measurements: electrical efficiency, acceptance angle, irradiance uniformity at solar cell plane. have collected here features different prototypes...

The potential for cost reduction in parabolic troughs (PT) large collector fields is real and will be achieved a variety of different ways. One problem certainly contributing to the costs Solar Thermal Electricity (STE) PT fact that have significant quantity receiver lines pipes bringing heat transfer fluid off from them. very pipe length (for instance 50MW Spain) source losses parasitic due pumping power, but also other related number pumps, amount (costly) circulating etc. In any given...

Defining and measuring spatial inequalities across the urban environment remains a complex elusive task which has been facilitated by increasing availability of large geolocated databases. In this study, we rely on mobile phone dataset an entropy-based metric to measure attractiveness location in Rio de Janeiro Metropolitan Area (Brazil) as diversity visitors’ residence. The results show that given measured entropy is important descriptor socioeconomic status location, can thus be used proxy...

A field experiment was conducted for ten years in a sandy soil the north part of Paraná State, Brazil. The samples were collected at 0-10 cm depth, both under coffee canopy and inter row space between plants, following treatments: Control, Leucaena leucocephala, Crotalaria spectabilis, breviflora, Mucuna pruriens, deeringiana, Arachis hypogaea Vigna unguiculata. legume crops influenced microbial activity, space. cultivation leucocephala increased biomass C, N P. Although L. provided higher...

The objective of this work was to evaluate the effect coffee (Coffea arabica L.) population densities on chemical and microbiological properties an Oxisol. carried out soil samples 0-20 cm depth originated from experimental site which had been used for tree spacing studies during 15 years, in Paraná State, Brazil. Eight populations were evaluated: 7143, 3571, 2381, 1786, 1429, 1190, 1020, 893 trees/ha. Increasing plant increased pH, exchangeable Ca, Mg, K, extractable P, organic carbon,...

The Simultaneous Multiple Surface (SMS) method in 3D geometry is presented. Giving two orthotomic input ray bundles and other output bundles, the provides an optical system with free-form surfaces that deflects rays of into corresponding vice versa. In nonimaging applications, allows controlling light emitted by extended source much better than single designs, also enables optics contour to be shaped without efficiency losses. expected find applications imaging

Getting a lower energy cost has always been challenge for concentrated photovoltaic. The FK concentrator enhances the performance (efficiency, acceptance angle and manufacturing tolerances) of conventional CPV system based on Fresnel primary stage secondary lens, while keeping its simplicity potentially low‐cost manufacturing. At same time F‐XTP (Fresnel lens+reflective prism), at first glance better potential but significantly higher sensitivity to errors. This work presents comparison...

The optical design presented here has been done in order to achieve superior performance comparison with the state-of-the-art Fresnel CPV systems. consists of a Photovoltaic Concentrator (CPV) comprising lens (F) as Primary Optical Element (POE) and dielectric solid RXI Secondary (SOE), both free-form surfaces (i.e. neither rotational nor linearly symmetric). It is first time RXI-type geometry applied secondary. This concentrator ultra-high CAP value ready accommodate more efficient cells...

An LED backlight has been designed using the flow-line design method. This method allows a very efficient control of light extraction. The is confined inside guide by total internal reflection, being extracted only specially calculated surfaces: ejectors. Backlight designs presented here have optical efficiency up to 80% (including Fresnel and absorption losses) with an FWHM below 30 degrees. experimental results first prototype are shown.