Search results for "Lens"

showing 10 items of 948 documents

The posterior chamber phakic refractive lens (PRL): a review

2012

Implantation of phakic intraocular lenses (pIOLs) is a reversible refractive procedure, preserving the patient’s accommodative function with minimal induction of higher order aberrations compared with corneal photoablative procedures. Despite this, as an intraocular procedure, it has potential risks such as cataracts, chronic uveitis, pupil ovalization, corneal endothelial cell loss, pigmentary dispersion syndrome, pupillary block glaucoma, astigmatism, or endophthalmitis. Currently, only two models of posterior chamber pIOLs are commercially available, the implantable collammer lens (STAAR Surgical Co.) and the phakic refractive lens (PRL; Zeiss Meditec). The number of published reports on…

Phakic Intraocular Lensesmedicine.medical_specialtygenetic structuresmedicine.medical_treatmentVisual performanceOptical qualityReviewAstigmatismRefraction OcularPhakic intraocular lensPhakic refractive lens (PRL)CataractPupilEndophthalmitisLens Implantation IntraocularCataractsOphthalmologyRefractive surgeryMyopiamedicineHumansRefractive surgeryÓpticaPosterior chamber phakic intraocular lensbusiness.industryPatient SelectionEquipment Designmedicine.diseaseeye diseasesOphthalmologyAberrations of the eyemedicine.anatomical_structureLens (anatomy)Posterior Capsule of the LensOptometrysense organsbusinessEye
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Cardiovascular effects of the methanol and dichloromethanol extracts fromMentha suaveolensEhrh.

2001

Methanol and dichloromethanol extracts of the leaves and stems of Mentha suaveolens Ehrh. have been tested for their effects on resting arterial blood pressure, heart rate and noradrenaline induced hypertension. Both extracts administered by i.v. bolus to urethane anaesthetized normotensive rats reduced the mean arterial blood pressure and heart rate, while only the dichloromethanol extract prevented the noradrenaline induced hypertension.

Pharmacologymedicine.medical_specialtybusiness.industryMentha suaveolensHemodynamicsPharmacognosyPharmacologyfood.foodlaw.inventionchemistry.chemical_compoundBolus (medicine)Blood pressurefoodEndocrinologychemistrylawInternal medicineHeart rateMedicineMethanolbusinessPhytotherapyPhytotherapy Research
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Flamenc de Xile, Flamenco chileno (VER0000233)

Chilean flamingo (Anglès), Flamant du Chili (Francès), Chileflamingo (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 10-2 Adultos

Phoenicopterus chilensis (Molina 1782)PhoenicopteridaeFlamencos
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Flamenc de Xile, Flamenco chileno (VER0000232)

Chilean flamingo (Anglès), Flamant du Chili (Francès), Chileflamingo (Alemany) Gabinet de Vertebrats (Departament de Zoologia), Facultat de Ciències Biològiques (Campus de Burjassot), C/ Doctor Moliner, s/n, Bloque B. 5é plant, Burjassot (Valencia). Armari: 10-2 Adultos

Phoenicopterus chilensis (Molina 1782)PhoenicopteridaeFlamencos
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The fast photon detection system of COMPASS RICH-1

2007

Abstract A fast photon detection system has been built for the upgrade of COMPASS RICH-1, the large size gaseous RICH detector in use at the COMPASS Experiment at the CERN SPS since 2001. The photon detectors of the central region have been replaced by a new system based on multi-anode photomultipliers coupled to individual fused silica lens telescopes and a fast readout electronics system, while in the outer region the existing MWPCs with CsI photocathodes have been equipped with a new readout system, based on the APV chip. RICH-1 has been successfully operated in its upgraded version during the 2006 run. We report on the upgrade design and construction, and on the preliminary characteriza…

PhotomultiplierNuclear and High Energy PhysicsPhotonMulti-anode photomultiplier tubesPhysics::Instrumentation and DetectorsUV lensesCOMPASS; Multi-anode photomultiplier tubes; Photon detection; RICH; UV lenses; Nuclear and High Energy Physics; InstrumentationCOMPASSlaw.inventionFAST-RICH; DEUTERON; READOUT; DESIGNOpticsDESIGNlawMulti-anode photomultiplier tubeCompassCOMPASS experimentRICHInstrumentationNuclear and High Energy PhysicPhysicsLarge Hadron Colliderbusiness.industryDetectorREADOUTDEUTERONLens (optics)UpgradePhoton detectionFAST-RICHUV lenseHigh Energy Physics::Experimentbusiness
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Lacunar fractal photon sieves

2007

We present a new family of diffractive lenses whose structure is based on the combination of two concepts: photon sieve and fractal zone plates with variable lacunarity. The focusing properties of different members of this family are examined. It is shown that the sieves provide a smoothing effect on the higher order foci of a conventional lacunar fractal zone plate. However, the characteristic self-similar axial response of the fractal zone plates is always preserved.

PhotonMaterials sciencebusiness.industryFOS: Physical sciencesZone plateAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materialslaw.inventionPhoton sieveFractalOpticsDiffractive lenslawLacunarityElectrical and Electronic EngineeringPhysical and Theoretical ChemistrybusinessSmoothingPhysics - OpticsOptics (physics.optics)Optics Communications
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<title>Family of devices for the study of laser eam behavior in particular conditions</title>

2002

Laser applications in science and technology are based on the special properties of laser radiation, such as monochromaticity, coherence, beam concentration and high power density. Since the laser was discovered, an ever increasing number of applications have been found for it in the most diversified fields. Despite this, its wide possibilities are still by no means fully known or exhausted. Further development is continually taking place in the design of new systems. The generation of the photons is in itself an optic-electronic process. The trajectory of the laser beam is linear. It could be modified by a lens or by a mirror. We built some devices, in order to know how a laser beam could …

Photonbusiness.industryComputer scienceOptical engineeringNozzlePhysics::OpticsHigh power densityLaserlaw.inventionLens (optics)OpticslawbusinessScience technology and societyCoherence (physics)SPIE Proceedings
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An Ultrasonic Lens Design Based on Prefractal Structures

2016

The improvement in focusing capabilities of a set of annular scatterers arranged in a fractal geometry is theoretically quantified in this work by means of the finite element method (FEM). Two different arrangements of rigid rings in water are used in the analysis. Thus, both a Fresnel ultrasonic lens and an arrangement of rigid rings based on Cantor prefractals are analyzed. Results show that the focusing capacity of the modified fractal lens is better than the Fresnel lens. This new lens is believed to have potential applications for ultrasonic imaging and medical ultrasound fields.

Physics and Astronomy (miscellaneous)General MathematicsPhysics::Optics02 engineering and technology01 natural scienceslaw.inventionFractalOpticsCantor prefractalslaw0103 physical sciencesComputer Science (miscellaneous)Medical ultrasoundMathematics010302 applied physicsbusiness.industrylcsh:MathematicsFresnel lensUltrasonic lens021001 nanoscience & nanotechnologylcsh:QA1-939Finite element methodUltrasonic imagingLens (optics)Chemistry (miscellaneous)FISICA APLICADAUltrasonic sensorSound focusing0210 nano-technologybusinessMATEMATICA APLICADA
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Characterizing Lenses and Lensed Stars of High-magnification Single-lens Gravitational Microlensing Events with Lenses Passing over Source Stars

2012

We present the analysis of the light curves of 9 high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436, MOA-2011-BLG-093, MOA-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300, and OGLE-2011-BLG-1101/MOA-2011-BLG-325. For all events, we measure the linear limb-darkening coefficients of the surface brightness profile of source stars by measuring the deviation of the light curves near the peak affected by the finite-source effect. For 7 events, we measure the Einstein radii and the lens-source relative proper motions. Among the…

Physics010308 nuclear & particles physicsBrown dwarfFOS: Physical sciencesAstronomy and Astrophysicsgravitational lensing: microAstrophysicsMass ratioLight curveGravitational microlensing01 natural sciencesGalaxy: bulgeGalaxy: bulge gravitational lensing: microEinstein radiuslaw.inventionLens (optics)StarsAstrophysics - Solar and Stellar AstrophysicsSettore FIS/05 - Astronomia e AstrofisicaSpace and Planetary Sciencelaw0103 physical sciencesSurface brightness010303 astronomy & astrophysicsSolar and Stellar Astrophysics (astro-ph.SR)
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Probing the Broad Line Region and the Accretion Disk in the Lensed Quasars HE0435-1223, WFI2033-4723, and HE2149-2745 using Gravitational Microlensing

2017

We use single-epoch spectroscopy of three gravitationally lensed quasars, HE0435-1223, WFI2033-4723, and HE2149-2745, to study their inner structure (BLR and continuum source). We detect microlensing-induced magnification in the wings of the broad emission lines of two of the systems (HE0435-1223 and WFI2033-4723). In the case of WFI2033-4723, microlensing affects two "bumps" in the spectra which are almost symmetrically arranged on the blue (coincident with an AlIII emission line) and red wings of CIII]. These match the typical double-peaked profile that follows from disk kinematics. The presence of microlensing in the wings of the emission lines indicates the existence of two different re…

Physics010308 nuclear & particles physicsContinuum (design consultancy)FOS: Physical sciencesAstronomy and AstrophysicsQuasarAstrophysicsGravitational microlensing01 natural sciencesAstrophysics - Astrophysics of GalaxiesSpectral lineAmplitudeSpace and Planetary ScienceAstrophysics of Galaxies (astro-ph.GA)0103 physical sciencesEmission spectrumSpectroscopy010303 astronomy & astrophysicsLine (formation)
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