18 research outputs found
Measuring micro-displacements of specular surfaces using speckle interferometry
The displacement field of an object surface can be measured by using speckle interferometry. This technique is based on the phenomenon of laser speckle and consists in correlating speckle interferograms taken after and before the deformation of the surface. The main requirement is that the surface under study must be optically rough to generate the speckle patterns to be correlated. In this paper, we present a very simple and intuitive method based on speckle interferometry to measure out-of-plane displacements on specular reflecting surfaces that generate no speckle patterns. The method consists in a modified digital speckle pattern interferometer which requires no special equipment other than that used in conventional speckle interferometers. The proposed method could find useful application in the measurement of thermal deformation of mirrors.Fil: Dolinko, Andrés Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Ingeniería Agrícola y Uso de la Tierra; ArgentinaFil: Galizzi, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; Argentin
Measurement of non-monotonous phase changes in temporal speckle pattern interferometry using a correlation method without a temporal carrier
Recently, a phase evaluation method was proposed to measure nanometric displacements by means of digital speckle pattern interferometry when the phase change introduced by the deformation is in the range [0,π) rad. This method is based on the evaluation of a correlation coefficient between two speckle interferograms generated by both deformation states of the object. In this paper, we present a novel technique to measure non-monotonous displacements in temporal speckle pattern interferometry using a correlation method without a temporal carrier. In this approach, the sign ambiguity is resolved automatically due to the introduction of a function that determines the correct sign of the displacement between two consecutive speckle interferograms. The rms phase errors introduced by the proposed method are determined using computer-simulated speckle interferograms. An application of the phase retrieval method to process experimental data is also presented.Fil: Tendela, Lucas Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Galizzi, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Federico, Roque Alejandro. Instituto Nacional de Tecnología Industrial. Centro de Electrónica e Informática; ArgentinaFil: Kaufmann, Guillermo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentin
Optical study of laser biospeckle activity in leaves of Jatropha curcas L. A noninvasive analysis of foliar endophyte colonization
Currently, the detection of endophytic fungi is determined mostly by invasive
methods, including direct isolation of fungal organismsfrom plant tissue in
growth media, molecular detection of endophyticfungi DNA from plant material by
PCR, or evaluation under microscopy techniques.In this work we explore the
potential of laser biospeckle activity (LBSA) to be usedfor the detection of
endophytic colonization of leaves of a promising energy crop, Jatropha curcas
L. We compared the laser biospeckle activityof endophyte infected and
uninfected J. curcas leaves. The differences between blade and veins (including
midrib) of the studied leaves was validated and growth parameters of the
studied plants were also analyzed using the normalized weigthed generalized
differencescoefficient (nWGD). The obtained results showeda relationship
between the endophytic burden of leaves and the LBS, suggesting that LSBA is a
useful tools to detect endophytic colonization in situ.Also, the increasedwater
movements inside leaves promoted by endophytic colonizationcould be explainby
the obtained data
A novel approach for measuring nanometric displacements by correlating speckle interferograms
Recently, two phase evaluation methods were proposed to measure nanometric displacements by means of digital speckle pattern interferometry when the phase changes introduced by the deformation are in the range [0, π) rad. However, one of these techniques requires separate recording of the intensities of the object and the reference beams which correspond to both the initial and the deformed interferograms. The other technique only works to measure out-of-plane displacements. In this paper, we present a novel approach that overcomes these limitations. The performance of the proposed method is analyzed using computer-simulated speckle interferograms and it is also compared with the results obtained with a phase-shifting technique. Finally, an application of the proposed phase method used to process experimental data is illustrated.Fil: Tendela, Lucas Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Galizzi, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentin
Joint transform correlator optical encryption system: Extensions of the recorded encrypted signal and its inverse Fourier transform
In this work we study the joint transform correlator setup, finding two analytical expressions for the extensions of the joint power spectrum and its inverse Fourier transform. We found that an optimum efficiency is reached, when the bandwidth of the key code is equal to the sum of the bandwidths of the image plus the random phase mask (RPM). The quality of the decryption is also affected by the ratio between the bandwidths of the RPM and the input image, being better as this ratio increases. In addition, the effect on the decrypted image when the detection area is lower than the encrypted signal extension was analyzed. We illustrate these results through several numerical examples.Fil: Galizzi, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Cuadrado Laborde, Christian Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. Universidad Catolica Argentina; Argentin
Experimental evaluation of a 3D wavelet-based phase recovery method in temporal speckle pattern interferometry
We test the performance of a phase recovery method based on a three-dimensional directional wavelet transform applied to the intensity signal measured by temporal speckle pattern interferometry (TSPI). We present and discuss several sources of uncertainty by analyzing experimental datasets recorded for an in-plane interferometer without introducing a temporal carrier. The dynamic phase data measured with the proposed method are compared with those obtained from the well-known one-dimensional Fourier transform phase recovery technique. In the Fourier method, the filtered Fourier transform for each intensity pixel is evaluated along the temporal direction. In contrast, the three-dimensional directional wavelet transform method uses the information of adjacent pixels and then increases the performance of the recovered dynamic phase results. The advantages and limitations of the three-dimensional directional wavelet transform approach are discussed, and a summary of conclusions from the analysis of TSPI data is also given.Fil: Galizzi, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Federico, Roque Alejandro. Instituto Nacional de Tecnología Industrial. Centro de Electrónica e Informática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kaufmann, Guillermo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentin
Tilt scanning interferometry: A numerical simulation benchmark for 3D metrology
Tilt scanning interferometry (TSI) is a novel experimental technique that allows the measurement of multicomponent displacement fields inside the volume of a sample. In this paper, we present a simulation model that allows for the evaluation of the speckle fields recorded in TSI when this technique is applied to the analysis of semitransparent scattering materials. The simulation is based on the convolution of the optical impulsive response of the optical system and the incident field amplitude. Different sections of the simulated imaging system are identified and the corresponding optical impulsive responses are determined. To evaluate the performance of the proposed model, a known internal displacement field as well as the illumination and detection strategies in a real TSI system are numerically simulated. Then, the corresponding depth-resolved out-of-plane and in-plane changes of phase are obtained by means of the data processing algorithm implemented in a TSI system.Fil: Galizzi, Gustavo Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. University of Loughborough; Reino UnidoFil: Ruiz, Pablo D.. University of Loughborough; Reino UnidoFil: Kaufmann, Guillermo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas. Universidad Nacional de Rosario. Centro Internacional Franco Argentino de Ciencias de la Información y de Sistemas; Argentin
Optical study of laser biospeckle activity in leaves of Jatropha curcas L.: a non-invasive and indirect assessment of foliar endophyte colonization
Currently, the detection of endophytic fungi is mostly determined by invasive methods, including direct isolation of fungal organisms from plant tissue in growth media, molecular detection of endophytic fungi DNA from plant material by PCR, or evaluation using microscopy techniques. In this work, we explore the potential of laser biospeckle activity (LBSA) for the detection of endophytic colonization of leaves of a promising energy crop, Jatropha curcas L. We compared the laser biospeckle activity of endophyte infected and uninfected J. curcas leaves. The differences between blade and veins (including midrib) of the studied leaves were validated and growth parameters of the studied plants were also analyzed using the normalized weighted generalized differences coefficient (nWGD), which characterizes a particular laser bioactivity behavior. The obtained results showed a relationship between the endophytic burden of leaves and the LBSA, suggesting that LBSA is a useful tool to indirectly detect endophytic colonization in situ. Also, the increased water movements inside leaves promoted by endophytic colonization could be explained by the obtained data.Fil: D'Jonsiles, Maria Fernanda. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Galizzi, Gustavo Ernesto. Universidad Nacional de Rosario. Facultad de Ciencias Exactas, Ingeniería y Agrimensura; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; ArgentinaFil: Dolinko, Andrés Ezequiel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Novas, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Ceriani Nakamurakare, Esteban Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; ArgentinaFil: Carmaran, Cecilia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentin
The DUNE Far Detector Vertical Drift Technology, Technical Design Report
International audienceDUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals
The DUNE Far Detector Vertical Drift Technology, Technical Design Report
DUNE is an international experiment dedicated to addressing some of the questions at the forefront of particle physics and astrophysics, including the mystifying preponderance of matter over antimatter in the early universe. The dual-site experiment will employ an intense neutrino beam focused on a near and a far detector as it aims to determine the neutrino mass hierarchy and to make high-precision measurements of the PMNS matrix parameters, including the CP-violating phase. It will also stand ready to observe supernova neutrino bursts, and seeks to observe nucleon decay as a signature of a grand unified theory underlying the standard model. The DUNE far detector implements liquid argon time-projection chamber (LArTPC) technology, and combines the many tens-of-kiloton fiducial mass necessary for rare event searches with the sub-centimeter spatial resolution required to image those events with high precision. The addition of a photon detection system enhances physics capabilities for all DUNE physics drivers and opens prospects for further physics explorations. Given its size, the far detector will be implemented as a set of modules, with LArTPC designs that differ from one another as newer technologies arise. In the vertical drift LArTPC design, a horizontal cathode bisects the detector, creating two stacked drift volumes in which ionization charges drift towards anodes at either the top or bottom. The anodes are composed of perforated PCB layers with conductive strips, enabling reconstruction in 3D. Light-trap-style photon detection modules are placed both on the cryostat's side walls and on the central cathode where they are optically powered. This Technical Design Report describes in detail the technical implementations of each subsystem of this LArTPC that, together with the other far detector modules and the near detector, will enable DUNE to achieve its physics goals