Search results for "IPM"
showing 10 items of 1361 documents
Efficient photo-thermal activation of gold nanoparticle-doped polymer plasmonic switches
2012
International audience; We report on the photo-thermal activation of dielectric loaded plasmonic switches comprised of gold nanoparticle-doped polymer deposited onto a gold film. The plasmonic switches rely on a multi-mode interferometer design and are fabricated by electron beam lithography applied to a positive resin doped with gold nanoparticles at a volume ratio of 0.52%. A cross-bar switching is obtained at telecom wavelengths by pumping the devices with a visible beam having a frequency within the localized surface plasmon resonance band of the embedded nanoparticles. By comparing the switching performances of doped and undoped devices, we show that for the modest doping level we cons…
Three-dimensional characterization of extreme ultraviolet mask blank defects by interference contrast photoemission electron microscopy
2008
A photoemission electron microscope based on a new contrast mechanism "interference contrast" is applied to characterize extreme ultraviolet lithography mask blank defects. Inspection results show that positioning of interference destructive condition (node of standing wave field) on surface of multilayer in the local region of a phase defect is necessary to obtain best visibility of the defect on mask blank. A comparative experiment reveals superiority of the interference contrast photoemission electron microscope (Extreme UV illumination) over a topographic contrast one (UV illumination with Hg discharge lamp) in detecting extreme ultraviolet mask blank phase defects. A depth-resolved det…
Refractive micro-optical elements for surface plasmons: from classical to gradient index optics.
2010
Controlling the propagation of surface plasmons along a metal-dielectric interface is a key feature for the development of surface plasmon based circuits. We have designed various two-dimensional refractive dielectric optical elements for surface plasmons (SP) and characterized their capacity to route SP, using near- or far-field techniques. We first present basic devices analogous to usual optical components and the associated challenges for SP optics. We then use a metamaterial approach to locally vary the refractive index and fabricate gradient index structures for SP circuitry.
Optical quality of rotationally symmetrical contact lenses derived from their power profiles.
2017
To present a methodology for evaluating the optical quality of rotationally symmetrical contact lenses (CLs) from a single power profile.Simulated rotationally symmetrical power profiles corresponding to different CLs designs (monofocal, two-zone center-near bifocal, and four-zone center-distance bifocal) were used to calculate the wavefront error profile by means of numerical integration. Then, each lens wavefront error profile was spun around the center to obtain the lens wavefront error surface. From the surface, monochromatic optical transfer functions (OTF), simulated images and the visual Strehl ratio based on the OTF (VSOTF) were obtained for different distances and pupil sizes (3 an…
Optical experiments on a crystallizing hard-sphere–polymer mixture at coexistence
2010
We report on the crystallization kinetics in an entropically attractive colloidal system using a combination of time resolved scattering methods and microscopy. Hard sphere particles are polystyrene microgels swollen in a good solvent (radius a=380nm, starting volume fraction 0.534) with the short ranged attractions induced by the presence of short polymer chains (radius of gyration rg = 3nm, starting volume fraction 0.0224). After crystallization, stacking faulted face centred cubic crystals coexist with about 5% of melt remaining in the grain boundaries. From the Bragg scattering signal we infer the amount of crystalline material, the average crystallite size and the number density of cry…
Simultaneous remote extraction of multiple speech sources and heart beats from secondary speckles pattern
2009
The ability of dynamic extraction of remote sounds is very appealing. In this manuscript we propose an optical approach allowing the extraction and the separation of remote sound sources. The approach is very modular and it does not apply any constraints regarding the relative position of the sound sources and the detection device. The optical setup doing the detection is very simple and versatile. The principle is to observe the movement of the secondary speckle patterns that are generated on top of the target when it is illuminated by a spot of laser beam. Proper adaption of the imaging optics allows following the temporal trajectories of those speckles and extracting the sound signals ou…
Optimization of a polarization imaging system for 3D measurements of transparent objects
2009
This paper presents a multispectral imaging system for 3D reconstruction of transparent objects based on "shape from polarization" technique. The originality of this work relies on a multispectral active lighting system which enables to cope with the two ambiguities on the zenith angle and azimuth angle. A calibration step allows optimising the polarimetric measurements. Example of a reconstructed transparent object is presented.
A Comparative Study of Cyclic Fatigue of 10 Different Types of Endodontic Instruments: an in Vitro Study
2019
Objective This study was designed to test the null hypothesis that there were no significant differences between size 25 files F360, F6 SkyTaper, Hyflex EDM, iRace, Neoniti, One Shape Protaper Next, Reciproc, Revo-S and Wave One Gold in terms of resistance to cyclic fatigue and length of broken fragments. Material and methods 300 new size 25 files of the systems studied were selected (n=30). The instruments were mechanized with a X-Smart Plus endo motor at the speed and torque recommended by the manufacturer, holding the instruments steady with a clamping mechanism, with passive adjustment and without pressure in a stainless-steel block. The time was calculated in seconds until fracture. Th…
Influence of Instrument Size on the Accuracy of Different Apex Locators: An In Vitro Study
2008
The aim of this in vitro investigation was to determine the accuracy of 4 different electronic apex locators (EALs) with 3 different instrument sizes. For this study 146 roots were embedded in an agar solution. Electronic measurements were made to the physiologic foramen (apical constriction) with the Elements Apex Locator, Justy II, Raypex 5, and ProPex II and K-type files sizes 08, 10, and 15. Statistical significances were calculated with the sign test (P < .001). Exact measurements to the physiologic foramen were made with the Elements Apex Locator, 36.99%, 39.04%, and 44.93%; Justy II, 38.62%, 32.41%, and 43.41%; Raypex 5, 42.76%, 39.31%, and 39.06%; and ProPex II, 38.62%, 43.45%, and …
Komparativno istraživanje oblikovanja četiriju rotirajućih sustava
2015
Svrha: U ovom istraživanju analizirali smo rezno područje, vrijeme instrumentacije, održavanje anatomije korijenskog kanala i neinstrumentirana područja dobivena korištenjem instrumenata F360®, Mtwo®, RaCe® i Hyflex® u ISO veličini 35. Materijali i metode: Odabrano je 120 zuba s jednim ravnim kanalom i podijeljeni su u četiri grupe. Radna duljina određena je radiološki. Zubi su rezani dijamantnim diskom, a presjeci su promatrani stereoskopskim mikroskopom Nikon SMZ-2T pod svjetiljkom Intralux 4000-1. Grupe su oblikovane predoperativnom analizom AutoCAD. Zubi su rekonstruirani s pomoću K-proširivača #10 i epoksi ljepila. Svaka grupa instrumentirana je jednim od četiriju sustava. Vrijeme inst…