Electronic Speckle Pattern Interferometry (ESPI) and Shearography (ESPSI) techniques have been used in the field of non-destructive testing for a long time, providing accuracy, and allowing whole field analysis of pure deformation (ESPI) or the gradient of deformation (ESPSI). One of the major weaknesses of this two techniques is linked to speckle de-correlation. When the deformation process produces a displacement greater than a certain proportion of the speckle size, there is a severe loss of coherence which limits the application of these techniques to processes with strong or fast deformations. In order to avoid this limitation, the use of a dynamically updated reference frame is tested in this work. First, in ESPI and ESPSI setups, a metacrylathe bar is used as specimen for testing procedures, and finally a human jaw bone will be used in an ESPSI setup. One basic and regular-shaped object, the bar, and a structurally 3D complex structure, the human jaw bone, with complex elastic properties are the samples to test.
In response to ever growing data traffic, significant efforts are being made to increase optical network capacity.
One promising candidate is mode-division multiplexing (MDM) in few-mode fibers, which uses space as a new
information-bearing dimension. A fundamental element for MDM is a modal transformer. Modal transformation
can be implemented in a free-space basis by using multi-region phase plates. In this work we present the design,
fabrication and characterization of monolithic binary phase plates by highly-uniform Ag+/Na+ ion-exchange in
glass. Diffracted optical field intensities have been measured and high quality mode transformation has been
confirmed.
Electronic Speckle Pattern Interferometry (ESPI) has been used in experiments to measure
displacement on the surface of bones undergoing external forces. However in order to asses directly the
derivative of the displacements a related technique, Shearography, is used. This technique has been
applied in biomechanical experiments although limited to small pieces of bone to determine their
elastic properties. In this work we propose the use of Shearing Speckle Interferometry to evaluate the
mechanical behaviour of the human mandible under compressive stress, simulating masticatory forces
or impacts, in order to analyze the strain distribution on mandibular bone.
We show how confocal microscopy can be used as a simple, fast and flexible technique to fabricate multiple diffractive
masks on a single plate. These masks are useful to make full bandgap photonic crystals with a woodpile structure in a
single illumination step. The versatility for the control of the confocal microscope allows to define the illumination area
and codify the features of the diffractive mask in a simple and straightforward way. The period of the diffraction grating
can be easily established by modifying the illumination area. This allows to control the dimensions of the woodpile
structures and consequently the bandgap spectral range of the fabricated structures.
In this work is presented a macroscopic quantum-mechanical analysis of quantum light progression in different
kinds of integrated photonic waveguide structures with coupled modes, and therefore with validity, for instance,
for integrated optical waveguides (conventional integrated optics), photonic crystal waveguides, nano-optical
waveguides (plasmonic modes) and so on. The main goal of the work is to give a consistent and explicit derivation
of the quantum Momentum operator, and therefore to calculate the corresponding Heisenberg's Equations.
Quantum propagation of nonclassical light states are analyzed in different linear and nonlinear integrated devices.
In this work we present an analysis of the propagation, based on the Dirac equation, of spinor-electron quantum
modes, that is, of spinor-electron guided waves in asymmetric 2D and 1D semiconductor nanostructures.
Spinor-electron modes are calculated by means of Dirac equation in an asymmetric 2D semiconductor structures,
analogous to the wellknown optical modes of the conventional integrated optics; moreover, by means of standard
methods well stablished in integrated photonics, such as Marcatili method or Knox-Toulios method, 1D electron
waveguides are studied. The study of these nanoelectronic devices based on electron waveguides in semiconductors
is directed to understand better the possibilities of linking between nanoelectronic and nanophotonic
devices.
A nonlinear integrated optical device, presenting an intrinsic bistable behaviour by means of the Kerr effect produced by counterpropagating beams, is presented. The proposed feedback mechanism, which preserves the spatial shape of the beams, is based on the transverse modal coupling of the beams to optical fibers through integrated multilenses. An optimum waveguiding design is presented to allow both the fabrication of this device by hybrid
integration on glass and show the results of bistability.
In this work we present the study of step-index channel directional couplers which can be fabricated on a buffer planar guide in a such a way that they can be properly designed to support separable modal fields, though the index profile is non separable. The main advantage of this approach is the great simplicity in the analysis, design and
fabrication of the directional couplers, or other different integrated strucutures, since it is possible to apply, for instance, the effective index method obtaining a quasi-exact solution for the modal fields. Analytical and numerical results will be presented to confirm that an accurate design of the operation properties of the
directional coupler can be achieved.
We present a technique to directly process silver ion- exchanged planar waveguides fabricated in soda-lime glass. The technique, that is regarded as complementary to the conventional lithography but with the inherent advantages of the direct processing of the material, is based on laser writing with a focused laser bema from an Ar+ laser, which induces a redistribution and aggregation of the small sliver clusters created in the glass during the ion-exchange process. We give a theoretical explanation of the physical processes that take place in the glass and expose experimental reslut of processing of silver ion-exchanged guides under different irradiation conditions. We expose the possible applications of this technique to integrated optics for 2D waveguiding, to optoelectronics for one-step electrode and waveguide fabrication, to planar optics for patterning of reflective components and to diffractive optics to fabricate conventional elements. We finally demonstrate some of this applications presenting devices fabricated by means of this technique.
Ion-Exchanged Glass Integrated Optics has received a considerably attention during the laser years because of their well-known advantages. On the other hand, ion- exchanged waveguide components are finding important applications in the implementation of analogue processing devices, optical sensing devices and some kind of circuit for optical communications. Many of these develop devices are based on channel guides, however planar components with optical confinement in only one dimension have been also recognized to be among the basic components of glass integrated optics. In this paper we show the specific advantages of using these kinds of integrated optical elements. Thus, conventional photolithographic techniques can be used with a great accuracy but within the high requirements needed for channeled devices. Likewise, as it will be shown, the components can be realized by simple selective ion-exchange processes in a few steps, and with a high transmission of guided light, in a monomode regime, through the various boundaries shaping the planar components. Finally, their planar configuration facilitates considerably the use of glass integrated devices with other materials and thus a high-performance hybrid optical devices can be achieved. In short, we show various approaches to the design and fabrication of planar components and presents several passive components implementing simple functions such as: beam-splitting, focusing, and so on, which are important for optical sensing and processing applications.
A simple, effective and low cost laser writing lithographic system is presented. This system with a simple optical design and interferometric control of the alignment is able to produce smallest optical features as 1 micrometers wide with high quality edges to produce prototypes of integrated optical elements by ion exchange in research laboratories. Results of several kinds of mask that can be generated for this systems as well as some of the integrated elements produced are shown.
The study of the mechanical behavior of the human jaw during chewing is helpful in several specific medical fields that cover the maxillo-facial area. In this work, electronic speckle pattern interferometry has been applied to study dead jaw bones under external stress which simulates the deformations induced during chewing. Fringes obtained after subtraction of two images of the jaw, the image of the relaxed jaw and that of the jaw under stress, give us information about the most stressed zones. The interferometric analysis proposed here is attractive as it can be done in real time with the jaw under progressive stress. Image processing can be applied for improving the quality of fringes. This research can be of help in orthognathic surgery, for example in diagnosis and treatment of fractured jaws, in oral surgery, and in orthodontics because it would help us to know the stress dispersion when we insert an osseointegrated implant or place an orthodontic appliance, respectively. Studying fragments of human jaw some results about its elasticity and flexibility were obtained.
We propose a new metrologic application of zone plates, using interferometric techniques, in order to detect changes in the refraction index of a dielectric parallel plate under the influence of the environmental parameters. The key of this kind of interferometer is a couple of circular zone plates produced with the proper combination of initial phase shift, in order to suppress the constant phase factors introduced with the system in the equilibrium state. In this way we are in quadratic condition and then we can measure the variation parameters with great accuracy and with the advantage of knowing the sign of it produced under external actions. The influence of the several fabrications parameters are discussed.
Derived in the comunicate formula allows to find equation of basic grid for desired moire pattern and kind of displacement. As an illustration few examples of potentially practical application are given.
An improvement in the accuracy of the axial distance measurement between two planes using a simple zone plate interferometer is proposed. In this case a Fresnel zone plate with initial phase shift between the 0th and 1st diffracted orders must be designed. 1. ZONE PLATE INTERFEROMETER. A simple method of measuring angular and axial misalignments between two different planes is possible by using a common-path zone plate /ZP/ interferometer. One plane is associated with a transmission Fresnel ZP being a reference plane whereas the second is connected with a plane mirror directing diffracted beams back to the ZP. When the ZP is illuminated by a plane wave the light passing throughout it is divid ed into several diffraction orders. After freespace propagation they are reflected by a plane mirror and go back to the ZP producing now a new set of diffracted orders for each one of the incidents. With a proper spatial filter system we select only two //O of the output wavefronts in order to observe the interference pattern produced by them. One of these two waves is generated by the virtual focus of the ZP and the other by the real focus. The positions of both focii depends variously on the relative orienta tion and position of the mirror in respect to the ZP plane. The shape and the frequency of'' the fringes in the interferometric pattern give
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