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55. Bending in the holograms stored in hydrogel matrices

Author

Berramdane, Kheloud, Ramirez, Manuel G., Lucío, María Isabel, Zezza, Paola, Bañuls, María-José, Maquieira, Ángel, Morales-Vidal, Marta, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad Politécnica de Valencia. Departamento de Química, Universidad Politécnica de Valencia. Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, and Holografía y Procesado Óptico

Subjects
Bending, Física Aplicada, Photopolymers, Holograms, Química Analítica, Óptica
Abstract

The study of the optical properties and behaviour of holograms stored in hydrogel matrices when the material is immersed in liquid medium represent a very important challenge currently. Hydrogels are 3D polymer networks capable of undergoing reversible volume changes. These hydrogels can be chemically modified to obtain materials with different properties such as to be sensitive to a range of relevant analytes. Emergent applications require that the holograms stored in hydrogels be time-stable in a liquid medium. One of the most important applications of this type of system are holographic sensors. Holographic sensors have advantages over other types of sensors such as the possibility of miniaturization due to the use of holographic techniques, the ability to produce three-dimensional images, real-time quantification, possibility of low-cost mass manufacturing and label-free analyte- responsive. Due to these advantages, these sensors have great potential to be used in different areas such as environmental detection, veterinary testing, pharmaceutical bioassays and medical diagnosis. Therefore, the optical behaviour of the holograms and the optimization of the hydrogel’s matrices must be well studied. When volume phase holograms are stored in hydrogels matrices in liquid medium, the holographic planes can undergo a bending process that give rise to asymmetries in the lateral lobes around the Bragg angle. This bending affect to the diffraction efficiency, wavelength of maximum diffraction efficiency and the angular sensibility. These parameters are used as signal transducers in holographic sensors in transmission mode. The general aim of this work has been study the bending that is produced in the holographic planes when unslanted transmission volume phase holographic grating with a frequency of 1200 lines/mm have been stored in hydrogel matrices based on acrylamide (AA) and N,N'-methylenebisacrylamide (MBA) using different solvents (dimethyl sulfoxide, water and buffer solution) during the manufacturing process. Considering previous works on bending, and grating attenuated hologram. This work was supported by the by “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006 and IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme) and by the “Ministerio de Ciencia e Innovación” of Spain (projects FIS2017-82919-R and PID2019-106601RB-I00).

Published
2022

56. Creating holography: 75th anniversary of Gabor’s invention

Author

Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Holografía y Procesado Óptico, and GITE - Física, Óptica y Telecomunicaciones

Subjects
Física Aplicada, Gabor, Holography, Leith, Denisyuk, Hologram, Historia de la Ciencia, Nobel Prize, Óptica
Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor’s invention of the holographic method and for which he received the Nobel Prize in Physics in 1971. The year 2022 also marks the sixtieth anniversary of the publication in 1962 of two seminal papers in the field of holography. In one of them Yuri Denisyuk introduces the reflection hologram and in the other paper Emmeth Leith and Juris Upatnieks describe the holographic process from a communication- theory viewpoint. In this paper, we carry out a brief description of the different “origins” of holography, making special mention to the way Gabor, Denisyuk y Leith established the basis, which made possible the spectacular development of holography from the invention of the laser at the beginning of the decade of 1960. This work was supported by the “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006; IDIFEDER/2021/014, potential FEDER funding) and by the “Ministerio de Ciencia e Innovación” of Spain (project PID2019-106601RB-I00).

Published
2022

57. Celebrating holography anniversaries: a historical perspective

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering. College of Arquitecture and Engineering, Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering. College of Arquitecture and Engineering, Beléndez, Augusto, Sheridan, John T., and Pascual, Inmaculada

Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor?s invention of the holographic method, what he called microscopy by reconstructed wave-fronts, as well as the 60th anniversary of the publication in 1962 of two seminal papers in the field of holography: the introduction of the reflection hologram by Yuri Denisyuk, and the description of the holographic process from the point of view of communication theory by Emmett Leith and Juris Upatnieks. Within the framework of these celebrations, a historical review of the origins of holography is presented with special emphasis on the contributions of Gabor, Denisyuk and Leith to the development of holography.

Published
2022

58. Processing of Holographic Hydrogels in Liquid Media: A Study by High-Performance Liquid Chromatography and Diffraction Efficiency

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universitat Politècnica de València. Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Universitat Politècnica de València. Departamento de Química, Berramdane, Kheloud, Ramirez, Manuel G., Zezza, Paola, Lucío, María Isabel, Bañuls, María-José, Maquieira, Ángel, Morales-Vidal, Marta, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universitat Politècnica de València. Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico (IDM), Universitat Politècnica de València. Departamento de Química, Berramdane, Kheloud, Ramirez, Manuel G., Zezza, Paola, Lucío, María Isabel, Bañuls, María-José, Maquieira, Ángel, Morales-Vidal, Marta, Beléndez, Augusto, and Pascual, Inmaculada

Abstract

The storage of time-stable holographic gratings in hydrogel matrices when the material is immersed in aqueous media is a real challenge at present. The optimization of the storage stages of the holograms must be properly investigated to identify the most suitable development processes. For this reason, this work is focused on the study of the optimization of the washing stages of the hydrogels based on acrylamide and N,N’-methylenebis(acrylamide) once unslanted transmission holograms have been stored. High-performance liquid chromatography and UV-visible measurements have been employed in our system to analyze the composition of the washing solutions. PBST and DMSO:H2O are used as solvents in the washing stages. The diffraction efficiencies are measured during the washing stages and after the storing of the holograms during several days in PBST. Maximum diffraction efficiencies of 38 and 27.6% are reached when PBST and DMSO:H2O are employed, respectively, for the washing process. Holograms show temporal stability after being stored immersed in PBST at 4 °C for 4 days.

Published
2022

59. Adulterant Detection in Peppermint Oil by Means of Holographic Photopolymers Based on Composite Materials with Liquid Crystal

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Miloua, Wafaa, Ortuño, Manuel, Navarro-Fuster, Víctor, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Miloua, Wafaa, Ortuño, Manuel, Navarro-Fuster, Víctor, Beléndez, Augusto, and Pascual, Inmaculada

Abstract

Diffraction gratings are recorded in a holographic photopolymer containing nematic liquid crystal and peppermint oil. The presence of the oil modifies the polymerization and the holographic response. The composite containing oil adulterated with triethyl citrate obtains a diffraction efficiency related to the oil’s purity. The results obtained suggest the possibility of developing a holographic chemical analysis method for quality control of raw materials.

Published
2022

60. Projectile motion revisited: Does the distance between the launcher and the object always increase?

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Castilla-La Mancha. Departamento de Física Aplicada, Universidad Nacional de Educación a Distancia (UNED). Centro Asociado de Albacete, Escobar García, Isabel, Arribas Garde, Enrique, Ramírez Vázquez, Raquel, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Castilla-La Mancha. Departamento de Física Aplicada, Universidad Nacional de Educación a Distancia (UNED). Centro Asociado de Albacete, Escobar García, Isabel, Arribas Garde, Enrique, Ramírez Vázquez, Raquel, and Beléndez, Augusto

Abstract

In this paper, we have shown that parabolic motion from a critical launch angle has an unexpected property related to the distance between the object and the launcher. This distance decreases in a time interval that occurs between two moments: one, in which distance has a maximum and another in which it has a minimum. As it will be shown, this only happens in launch angles greater than cos∅c = 1/3, that is ∅c ≅ 70.53º. The launch we have studied occurs from the ground and we have not taken into account air friction. We have not considered the possible variations in the acceleration of gravity, that is, we have taken it as a constant throughout the movement of the projectile. We have used dimensionless coordinates so that the focus is on the angular variable. In addition, at the end of the study, we have used polar variables to visualize what happened. This is a very didactic approach, which can be used in the first year of STEM university degrees. It will also prove useful for teachers that wish to explain parabolic motion in their classes.

Published
2022

61. Polarimetric analysis of cross-talk phenomena induced by the pixelation in PA-LCoS devices

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Francés, Jorge, Márquez, Andrés, Neipp, Cristian, Puerto, Daniel, Gallego, Sergi, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Francés, Jorge, Márquez, Andrés, Neipp, Cristian, Puerto, Daniel, Gallego, Sergi, Pascual, Inmaculada, and Beléndez, Augusto

Abstract

Liquid crystal on silicon (LCoS) microdisplays are an element commonly found in advanced photonic applications. Phase-only modulation and spatial light modulators (SLMs) use parallel-aligned LCoS (PA-LCoS) microdisplays due to their large resolution and small pixel size. However, the crosstalk between neighbouring pixels induces several phenomena, i.e. the smoothing of the electric field in the interpixel region known as fringing fields, out-of-plane reorientation of the liquid crystal director, and diffraction effects due to the finite pixel grid pattern. These effects degrade the performance in SLM applications. Therefore, a rigorous numerical analysis is carried out based on a full 3D model that estimates the LC director distribution of the PA-LCoS microdisplay through uniform applied voltages. Once the LC director distribution is known, a numerical finite-difference scheme simulates light propagation across the structure. Here, the impact of crosstalk is analysed from the polarimetric point of view for different pixel and interpixel sizes. It has been found that the finite-patterned pixel scheme induces the phenomena previously addressed, degrading the responses of the Stokes vector components S0, and S1 and also the degree of polarization (DOP). Furthermore, the impact over these parameters is generally inversely proportional to the fill factor. To isolate the influence of diffraction, out-of-plane, and fringing fields effects is challenging since all phenomena are mixed in both time and space, however we have found some useful trends.

Published
2022

62. Green and wide acceptance angle solar concentrators

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Morales-Vidal, Marta, Lloret, Tomás, Ramirez, Manuel G., Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Morales-Vidal, Marta, Lloret, Tomás, Ramirez, Manuel G., Beléndez, Augusto, and Pascual, Inmaculada

Abstract

A low-toxicity photopolymer was employed to prepare holographic solar concentrators (HSCs). The main aim of this study is to obtain a versatile holographic element to concentrate the sunlight from different relative positions of the Sun during the day, avoiding the need of expensive tracking systems. Multiplexed holographic elements that combine symmetric and asymmetric holographic lenses of low frequency (545 l/mm) have been recorded in the same plate to concentrate the sunlight from sunrise to sunset. The holographic behavior of HSCs has been studied by measuring the angular diffraction efficiency at 633 nm (close to the maximum response of silicon cells). The efficiency of the complete system “HSC-solar cell” has been evaluated by measuring the short-circuit current (Isc) under solar illumination at different incident angles. This study overcomes the trade-off between good efficiency and high incident acceptance angle, showing an important breakthrough to obtain wide acceptance angle systems.

Published
2022

63. Creating holography: 75th anniversary of Gabor’s invention

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., and Pascual, Inmaculada

Abstract

The year 2022 marks the 75th anniversary of Dennis Gabor’s invention of the holographic method and for which he received the Nobel Prize in Physics in 1971. The year 2022 also marks the sixtieth anniversary of the publication in 1962 of two seminal papers in the field of holography. In one of them Yuri Denisyuk introduces the reflection hologram and in the other paper Emmeth Leith and Juris Upatnieks describe the holographic process from a communication- theory viewpoint. In this paper, we carry out a brief description of the different “origins” of holography, making special mention to the way Gabor, Denisyuk y Leith established the basis, which made possible the spectacular development of holography from the invention of the laser at the beginning of the decade of 1960.

Published
2022

64. Adulterant detection in peppermint oil by means of holographic photopolymers based on composite materials with liquid crystal

Author

Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Miloua, Wafaa, Ortuño, Manuel, Navarro-Fuster, Víctor, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Miloua, Wafaa, Ortuño, Manuel, Navarro-Fuster, Víctor, Beléndez, Augusto, and Pascual, Inmaculada

Abstract

In this work, we use a holographic dispersed liquid crystal (HPDLC) to detect a substance added as adulterant to peppermint oil. Volume diffraction gratings are recorded in two samples of HPDLC with and without peppermint oil respectively using a Nd:YAG laser tuned at 532 nm. The adulterant is detected due to the differences obtained for the maximum diffraction efficiency, which are related to the purity of the oil.

Published
2022

65. Bending in the holograms stored in hydrogel matrices

Author

Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad Politécnica de Valencia. Departamento de Química, Universidad Politécnica de Valencia. Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Berramdane, Kheloud, Ramirez, Manuel G., Lucío, María Isabel, Zezza, Paola, Bañuls, María-José, Maquieira, Ángel, Morales-Vidal, Marta, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad Politécnica de Valencia. Departamento de Química, Universidad Politécnica de Valencia. Instituto Interuniversitario de Investigación de Reconocimiento Molecular y Desarrollo Tecnológico, Berramdane, Kheloud, Ramirez, Manuel G., Lucío, María Isabel, Zezza, Paola, Bañuls, María-José, Maquieira, Ángel, Morales-Vidal, Marta, Beléndez, Augusto, and Pascual, Inmaculada

Abstract

The study of the optical properties and behaviour of holograms stored in hydrogel matrices when the material is immersed in liquid medium represent a very important challenge currently. Hydrogels are 3D polymer networks capable of undergoing reversible volume changes. These hydrogels can be chemically modified to obtain materials with different properties such as to be sensitive to a range of relevant analytes. Emergent applications require that the holograms stored in hydrogels be time-stable in a liquid medium. One of the most important applications of this type of system are holographic sensors. Holographic sensors have advantages over other types of sensors such as the possibility of miniaturization due to the use of holographic techniques, the ability to produce three-dimensional images, real-time quantification, possibility of low-cost mass manufacturing and label-free analyte- responsive. Due to these advantages, these sensors have great potential to be used in different areas such as environmental detection, veterinary testing, pharmaceutical bioassays and medical diagnosis. Therefore, the optical behaviour of the holograms and the optimization of the hydrogel’s matrices must be well studied. When volume phase holograms are stored in hydrogels matrices in liquid medium, the holographic planes can undergo a bending process that give rise to asymmetries in the lateral lobes around the Bragg angle. This bending affect to the diffraction efficiency, wavelength of maximum diffraction efficiency and the angular sensibility. These parameters are used as signal transducers in holographic sensors in transmission mode. The general aim of this work has been study the bending that is produced in the holographic planes when unslanted transmission volume phase holographic grating with a frequency of 1200 lines/mm have been stored in hydrogel matrices based on acrylamide (AA) and N,N'-methylenebisacrylamide (MBA) using different solvents (dimethyl sulfoxide, water and buff

Published
2022

66. Parameter analysis for LCoS devices as a function of the voltage and wavelength

Author

Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y anatomía, Sánchez-Montes, Adriana R., Márquez, Andrés, Martínez Guardiola, Francisco Javier, Francés, Jorge, Neipp, Cristian, Calzado Estepa, Eva María, Puerto, Daniel, Pascual, Inmaculada, Gallego, Sergi, Beléndez, Augusto, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y anatomía, Sánchez-Montes, Adriana R., Márquez, Andrés, Martínez Guardiola, Francisco Javier, Francés, Jorge, Neipp, Cristian, Calzado Estepa, Eva María, Puerto, Daniel, Pascual, Inmaculada, Gallego, Sergi, and Beléndez, Augusto

Abstract

A model describing the parameter and wavelength dependencies not only of retardance, but also its flicker in liquid-crystal-on-silicon spatial light modulators (LCoS SLMs), is presented. We provide results for different digital addressing sequences producing different levels of flicker.

Published
2022

67. Photopolymers comparison for see-through applications

Author

Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Sirvent-Verdú, Joan Josep, Bravo Francés, Juan Carlos, Colomina-Martínez, Jaume, Neipp, Cristian, Puerto, Daniel, Gallego, Sergi, Beléndez, Augusto, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Sirvent-Verdú, Joan Josep, Bravo Francés, Juan Carlos, Colomina-Martínez, Jaume, Neipp, Cristian, Puerto, Daniel, Gallego, Sergi, and Beléndez, Augusto

Abstract

We have developed a coupled waveguide system based on slanted transmission gratings recorded in photopolymers. In this work we compare the behavior of four different photopolymers for this high demanded application.

Published
2022

68. Holography: 50th anniversary of Dennis Gabor’s Nobel Prize: Part I. A historical perspective

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Beléndez, Augusto, Sheridan, John T., and Pascual, Inmaculada

Abstract

A historical review of the origins of holography is presented. Special emphasis is placed on the contributions of Gabor, Denisyuk and Leith to the development of holography, to motivate and inspire students and young researchers.

Published
2022

69. Holography: 50th anniversary of Dennis Gabor’s Nobel Prize: Part II. An engineering perspective

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Sheridan, John T., Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, Sheridan, John T., Beléndez, Augusto, and Pascual, Inmaculada

Abstract

The holographic principle, discovered by Gabor, and realized by Leith & Upatnieks and Denisyuk is discussed. The intrinsic value of this idea and its continuing ability to motivate and inspire engineers and applied physicists is reviewed.

Published
2022

70. Precise-Integration Time-Domain for Optical Anisotropic Media

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Sirvent-Verdú, Joan Josep, Francés, Jorge, Gallego, Sergi, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Sirvent-Verdú, Joan Josep, Francés, Jorge, Gallego, Sergi, and Beléndez, Augusto

Abstract

The Precise-Integration Time-Domain (PITD) formulation permits to break through the Courant- Friedrich-Levy (CFL) condition, which limits the accuracy, stability, and indirectly the applicability of the traditional Finite-Difference Time-Domain (FDTD) method. This characteristic permits considering larger time steps than the largest one fixed by the CFL condition. As the conventional FDTD scheme, PI also takes the spatial derivatives through the central finite-difference scheme. This step sets up a set of ordinary differential equations (ODEs) that are solved using the PI Technique. Here, the technique is applied to different periodic and anisotropic optical media. More precisely, to anisotropic polarization gratings (PG). PG is based on a periodically patterned, uniaxial birefringence in the grating plane that modulates the polarization of light instead of its amplitude.

Published
2022

71. Holographic Lens Resolution Using the Convolution Theorem

Author

Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Física Aplicada, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Lloret, Tomás, Morales-Vidal, Marta, Navarro-Fuster, Víctor, Ramirez, Manuel G., Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Física Aplicada, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Lloret, Tomás, Morales-Vidal, Marta, Navarro-Fuster, Víctor, Ramirez, Manuel G., Beléndez, Augusto, and Pascual, Inmaculada

Abstract

The similarity between object and image of negative asymmetrical holographic lenses (HLs) stored in a low-toxicity photopolymer has been evaluated theoretically and experimentally. Asymmetrical experimental setups with negative focal lengths have been used to obtain HLs. For this purpose, the resolution of the HLs was calculated using the convolution theorem. A USAF 1951 test was used as an object and the impulse responses of the HLs, which in this case was the amplitude spread function (ASF), were obtained with two different methods: using a CCD sensor and a Hartmann Shack (HS) wavefront sensor. For a negative asymmetrically recorded HL a maximum resolution of 11.31 lp/mm was obtained. It was evaluated at 473 nm wavelength. A theoretical study of object-image similarity had carried out using the MSE (mean squared error) metric to evaluate the experimental results obtained quantitatively.

Published
2022

72. Second comment on 'Maxwell's equations and Lorentz transformations'

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Beléndez, Augusto, Sirvent-Verdú, Joan Josep, Gallego, Sergi, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Beléndez, Augusto, Sirvent-Verdú, Joan Josep, and Gallego, Sergi

Abstract

Aguirregabiria et al (2022) Eur. J. Phys. 43 035603 obtained the Lorentz transformations by assuming the invariance of Maxwell's equations in vacuum under inertial transformations. However, they do not initially assume that these transformations must be linear. Later, Redzic (2022) Eur. J. Phys. 43 068002 indicates that it is necessary to explicitly assume the linearity of these transformations to avoid a remarkable and surprising result. Now it is shown that it is not necessary to make the assumption that the transformation equations between inertial reference frames must be linear, but that this linearity is a consequence of the homogeneity of space-time.

Published
2022

73. Monte-Carlo based analysis of polarimetric calibration of liquid crystal devices

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Márquez, Andrés, Sánchez-Montes, Adriana R., Francés, Jorge, Puerto, Daniel, Calzado Estepa, Eva María, Gallego, Sergi, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Márquez, Andrés, Sánchez-Montes, Adriana R., Francés, Jorge, Puerto, Daniel, Calzado Estepa, Eva María, Gallego, Sergi, Pascual, Inmaculada, and Beléndez, Augusto

Abstract

An advanced polarimetric model for liquid crystal devices is presented and the sources of uncertainty to determine the values of its parameters are evaluated using a Monte-Carlo approach.

Published
2022

80. Monte-Carlo based analysis of polarimetric calibration of liquid crystal devices

Author

Márquez, Andrés, Sánchez-Montes, Adriana R., Francés, Jorge, Puerto, Daniel, Calzado Estepa, Eva María, Gallego, Sergi, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, and Holografía y Procesado Óptico

Subjects
Liquid crystal, Polarimetry
Abstract

An advanced polarimetric model for liquid crystal devices is presented and the sources of uncertainty to determine the values of its parameters are evaluated using a Monte-Carlo approach. Work funded by the “Generalitat Valenciana” (Spain) (IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme; and projects PROMETEO/2021/006 and BEST/2021/021), “Ministerio de Ciencia e Innovación” of Spain (project PID2019-106601RB-I00), by the ‘‘Universidad de Alicante’’ (UATALENTO18-10; ACIE-20-10). ARS-M wishes to thank the “Generalitat Valenciana” for a grant (GRISOLIAP/2021/106).

Published
2022
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83. Analytical evaluation of normalization criteria for the diffraction efficiency of blazed gratings on LCoS devices

Author

Márquez, Andrés, Martínez Guardiola, Francisco Javier, Francés, Jorge, Neipp, Cristian, Calzado Estepa, Eva María, Puerto, Daniel, Alvarez, Mariela L., Gallego, Sergi, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, and Holografía y Procesado Óptico

Subjects
Física Aplicada, Blazed gratings, Diffraction efiiciency, Liquid-crystal-on-silicon spatial light modulators, Óptica
Abstract

Through analytical expressions, three experimental-based normalizations are evaluated for the diffraction efficiency of blazed gratings on LCoS devices. We find that non-inclusion of the fill factor, usually the case, leads to wrong conclusions. Ministerio de Ciencia e Innovación, Spain (FIS2017-82919-R (MINECO/AEI/FEDER, UE)); Generalitat Valenciana, Spain (IDIFEDER/2021/014, potential FEDER funding); Universidad de Alicante, Spain (UATALENTO18-10).

Published
2021

84. Tunable focal photopolymer lenses printed for the first time by laser-induced-forward transfer without a sacrificial layer

Author

Puerto, Daniel, Gallego, Sergi, Constantinescu, Cătălin-Daniel, Florian, Camilo, Ortuño, Manuel, Márquez, Andrés, Pascual, Inmaculada, Beléndez, Augusto, Alloncle, Anne Patricia, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Aix-Marseille University. CNRS, Lab Lasers Plasmas et Procédés Photoniques, Princeton University. Princeton Institute for the Science and Technology of Materials, and Holografía y Procesado Óptico

Subjects
Tunable lenses, Física Aplicada, Photopolymers, Lens array, Óptica
Abstract

The fabrication of polymeric lens arrays on flexible surfaces for its use in wide-field visual systems is a challenge that is being addressed by using the Laser Induced Forward Transfer (LIFT) technique. The objective is to achieve polymer laser printing by improving both the overall printing quality and the manufacturing time of these lens matrices compared to other techniques. Another challenge when using tunable polymers is the customization of tunable focal lenses dynamically controlling their optical properties. In this work we address both aspects by using a tunable photopolymer thanks to liquid crystal molecules, such as H-PDLC. The work was supported by the “Ministerio de Ciencia e Innovación” of Spain (projects FIS2017-82919-R; PID2019-106601RB-I00), by the ‘‘Universidad de Alicante’’ (UATALENTO18-10; ACIE-20-10), and by Generalitat Valenciana (projects BEST/2021/021; IDIFEDER/2021/014, potential FEDER funding), and Marie Skłodowska Curie Postdoctoral Global Fellowship “FOCUSIS” grant agreement 844977.

Published
2021

87. 2D Green’s tensor for the analysis of dielectric structures with translational geometries

Author

Taleb, Soumia Imane, Neipp, Cristian, Francés, Jorge, Martínez Guardiola, Francisco Javier, Alvarez, Mariela L., Márquez, Andrés, Gallego, Sergi, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, and Holografía y Procesado Óptico

Subjects
Scattering, Maxwell equations, Física Aplicada, Green’s tensor, Óptica
Abstract

In this work we present simulations of dielectric structures based on the volume integral method. The formalism is based on the solution of Helmholtz equation using the Green’s tensor technique. By using this technique, the second order differential equation (Helmholtz equation) is transformed into an implicit integral equation. In this work the two dimensional Green tensor will be derived in order to study dielectric structures with translational symmetry. The method is firstly compared with other methods existing in the literature for homogeneous circular dielectric cylinders in order to test the validity of the method proposed. Then numerical simulations of other structures such as dielectric cylinders with elliptical base are performed. This work was supported by the “Ministerio de Ciencia e Innovación” (Spain) under project FIS2017-82919-R (MINECO/AEI/FEDER, UE).

Published
2021

88. Influence of the introduction of peppermint oil as additive in the composition of HPDLC photopolymer and holographic response obtained

Author

Miloua, Wafaa, Ortuño, Manuel, Morales-Vidal, Marta, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, and Holografía y Procesado Óptico

Subjects
Liquid crystal, Física Aplicada, Holography, Photopolymer, Óptica
Abstract

Holography is an optical technique that allows the recording and the reconstruction of the wave front of an object; and it permits us to obtain the three dimensional images of a material. The use of photopolymers is justified by their properties such as the higher diffraction efficiency with an acceptable energetic sensitivity, and other special characteristic, which are added just by adding liquid crystal, like the capacity of variation of the electro optical properties by means of an electric field. In this article, attempt has been made to see the influence of the introduction of peppermint oil as additive in the composition of HPDLC to see the different holographic responses. Volume diffraction gratings are recorded in two samples of HPDLC with and without peppermint oil respectively using a Nd:YAG laser tuned at 532 nm. Peppermint oil is used in this study since it.s a naturel oil with specified properties that are compatible with the HPDLC photopolymer. The proprieties related to viscosity, density color and solubility are similar to those of the stander components of the photopolymer Since it is very important to develop material with ecofriendly properties, the use of natural components in these materials can improve properties related to environment as peppermint oil has the similar properties as the other components, and also It can be a good concurrent to replace some of the components to have a more ecofriendly photopolymer Peppermint oil is soluble in the photopolymer. When the oil is added to the composition, the diffraction efficiency is decreased. This could be related to the polymerization or the PIPS process. Este trabajo ha sido financiado por el Ministerio de Ciencia e Innovación con los proyectos FIS2017-82919-R (MINECO/AEI/FEDER, UE) y PID2019-106601RB-I00, y la Generalitat Valenciana con el proyecto CDEIGENT/2018/024.

Published
2021

90. Codification effect in the error number introduced in a HDSS

Author

Martínez Guardiola, Francisco Javier, Márquez, Andrés, Calzado Estepa, Eva María, Gallego, Sergi, Puerto, Daniel, Morales-Vidal, Marta, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, and Holografía y Procesado Óptico

Subjects
PA-LCoS, Física Aplicada, Almacenamiento digital, Modelado, Holografía, Dispositivos de cristal líquido, Relación señal-ruido, Óptica
Abstract

En este trabajo se presentan resultados preliminares sobre el efecto de la codificación de los datos digitales introducidos en un sistema de almacenamiento holográfico de información. Para ello se introducen una serie de fuentes de ruido que afectan a las imágenes que usamos como entrada de datos. Estas fuentes de ruido son las que se observan principalmente en el montaje real, por lo que se trata de imitar la degradación del sistema para poder tener un modelo que nos ayude a identificar los parámetros más disruptivos en el tratamiento óptico de la señal y cómo influye la introducción de una codificación en dicha imagen. In this work we present preliminary results about the codification effect over the digital data introduced in a Holographic Data Storage System (HDSS). In this sense, we introduce a series of noise sources that affects to the images used as data in the system input. These noise sources are related with the different degradations that we observed in the real setup, we are trying to model the system degradation in order to obtain a computational model that helps us to indentify the more disruptive parameters in the optical signal processing and how affects the introduction of a codification in the input image. Este trabajo ha sido financiado por el Ministerio de Ciencia e Innovación con los proyectos FIS2017-82919-R (MINECO/AEI/FEDER, UE) y PID2019-106601RB-I00, la Generalitat Valenciana con los proyectos CDEIGENT/2018/024 y GV/2019/021, y la Universidad de Alicante con el proyecto UATALENTO18-10.

Published
2021

92. Holography: 50th Anniversary of Dennis Gabor’s Nobel Prize. Part I. A historical perspective

Author

Beléndez, Augusto, Sheridan, John T., Pascual, Inmaculada, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, University College Dublin. School of Electrical and Electronic Engineering, and Holografía y Procesado Óptico

Subjects
Emmett Leith, Dennis Gabor, Yuri Denisyuk, Física Aplicada, Holography, Historical perspective, Óptica
Abstract

A historical review of the origins of holography is presented. Special emphasis is placed on the contributions of Gabor, Denisyuk and Leith to the development of holography, to motivate and inspire students and young researchers. This work was supported by the by “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006 and IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme), by the “Ministerio de Ciencia e Innovación” of Spain (projects FIS2017-82919-R and PID2019-106601RB-I00), and by the Science Foundation Ireland, The Irish Research Council for Science Engineering and Technology, Enterprise Ireland, and the European Commission.

Published
2021
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93. FACTORES QUE AFECTAN EL RENDIMIENTO ACADÉMICO

Author

Ramirez-Vazquez, Raquel, Escobar, Isabel, Beléndez, Augusto, and Arribas, Enrique

Subjects
Factores, Alumnos, Sistema educativo, Rendimiento académico, Ámbitos, Scopes, Academic performance, Students, Factors, Desempenho acadêmico. Fatores. Âmbito. Alunos. Sistema educativo
Abstract

Every teacher has several questions in mind. He wonders if the planned objectives have been achieved, if the students meet the expectations, what resources I use to evaluate them. Classifying students by their academic performance, they are usually separated between high and low performance, without further nuances. In this study we intend to know the factors that affect academic performance and the traits of the teachers preferred by students, which allow greater communication in class. For this, a questionnaire was applied to a sample of 176 students in the last cycle of Primary Education (11-12 years) and first cycle of Secondary Education (12-13 years) in the city of Albacete (Spain). The results are clear, the students prefer the following qualities among their teachers: sympathy, good humor, carrying out complementary and extracurricular activities, understanding, motivation and respect. And the least preferred trait was demand.Every teacher has several questions in mind. He wonders if the planned objectives have been achieved, if the students meet the expectations, what resources I use to evaluate them. Classifying students by their academic performance, they are usually separated between high and low performance, without further nuances. In this study we intend to know the factors that affect academic performance and the traits of the teachers preferred by students, which allow greater communication in class. For this, a questionnaire was applied to a sample of 176 students in the last cycle of Primary Education(11-12 years) and first cycle of Secondary Education(12-13 years) in the city of Albacete (Spain). Todo profesor tiene en mente varios interrogantes. Se pregunta sobre si se habrán alcanzados los objetivos previstos, sobre si los alumnos cumplen con las expectativas, qué recursos utilizo para evaluarlos. Clasificando a los alumnos por su rendimiento académico, se suelen separar entre alto y bajo rendimiento, sin más matices. En este estudio pretendemos conocer los factores que afectan el rendimiento académico y los rasgos de los profesores preferidos por los alumnos, que permiten una mayor comunicación en clase. Para ello se aplicó un cuestionario a una muestra de 176 alumnos de último ciclo de Educación Primaria (11-12 años) y primer ciclo de Educación Secundaria (12-13 años) en la ciudad de Albacete (España). Los resultados son claros, los alumnos/as prefieren las siguientes cualidades entre sus profesores/as: la simpatía, el buen humor, la realización de actividades complementarias y extraescolares, la comprensión, la motivación y el respeto. Y el rasgo menos preferido fue la exigencia. Todo profesor tiene en mente varios interrogantes. Se pregunta sobre si se habrán alcanzados los objetivos previstos, sobre si los alumnos cumplen con las expectativas, qué recursos utilizo para evaluarlos. Clasificando a los alumnos por su rendimiento académico, se suelen separar entre alto y bajo rendimiento, sin más matices. En este estudio pretendemos conocer los factores que afectan el rendimiento académico y los rasgos de los profesores preferidos por los alumnos, que permiten una mayor comunicación en clase. Para ello se aplicó un cuestionario a una muestra de 176 alumnos de último ciclo de Educación Primaria (11-12 años) y primer ciclo de Educación Secundaria (12-13 años) en la ciudad de Albacete (España). Los resultados son claros, los alumnos/as prefieren las siguientes cualidades entre sus profesores/as: la simpatía, el buen humor, la realización de actividades complementarias y extraescolares, la comprensión, la motivación y el respeto. Y el rasgo menos preferido fue la exigencia.

Published
2020

94. Closed-form solutions for the quadratic mixed-parity nonlinear oscillator

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Castilla-La Mancha. Departamento de Física Aplicada, Beléndez, Augusto, Hernández Prados, Antonio, Beléndez, Tarsicio, Arribas Garde, Enrique, Alvarez, Mariela L., Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Universidad de Castilla-La Mancha. Departamento de Física Aplicada, Beléndez, Augusto, Hernández Prados, Antonio, Beléndez, Tarsicio, Arribas Garde, Enrique, and Alvarez, Mariela L.

Abstract

Closed-form exact solutions for periodic motions of a nonlinear oscillator, which contains a quadratic mixed-parity restoring force, are derived analytically. This oscillator is characterised by two real parameters, which are the coefficients of the linear and the quadratic terms, and has single-well potential. All possible combinations of positive and negative values of these coefficients providing periodic motions are considered, and two families of exact solutions are obtained in terms of Jacobi elliptic functions. The periods are given in terms of the complete elliptic integral of the first kind, the behaviour of these periods as a function of the initial amplitude is analysed, and the exact solutions for certain values of these parameters are plotted.

Published
2021

95. Validation of Fresnel–Kirchhoff Integral Method for the Study of Volume Dielectric Bodies

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Taleb, Soumia Imane, Neipp, Cristian, Francés, Jorge, Márquez, Andrés, Alvarez, Mariela L., Hernández Prados, Antonio, Gallego, Sergi, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Taleb, Soumia Imane, Neipp, Cristian, Francés, Jorge, Márquez, Andrés, Alvarez, Mariela L., Hernández Prados, Antonio, Gallego, Sergi, and Beléndez, Augusto

Abstract

In this work, we test a nondestructive optical method based on the Fresnel–Kirchhoff integral, which could be applied to different fields of engineering, such as detection of small cracks in structures, determination of dimensions for small components, analysis of composition of materials, etc. The basic idea is to apply the Fresnel–Kirchhoff integral method to the study of the properties of small-volume dielectric objects. In this work, we study the validity of this method. To do this, the results obtained by using this technique were compared to those obtained by rigorously solving the Helmholtz equation for a dielectric cylinder of circular cross-section. As an example of the precision of the method, the Fresnel–Kirchhoff integral method was applied to obtain the refractive index of a hair by fitting the theoretical curve to the experimental results of the diffraction pattern of the hair measured with a CCD camera. In a same manner, the method also was applied to obtain the dimensions of a crack artificially created in a piece of plastic.

Published
2021

96. Waveguide couplers based on HPDLC for see-through applications: initiator optimization

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Gallego, Sergi, Puerto, Daniel, Neipp, Cristian, Ortuño, Manuel, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Gallego, Sergi, Puerto, Daniel, Neipp, Cristian, Ortuño, Manuel, Pascual, Inmaculada, and Beléndez, Augusto

Abstract

Polymer nanocomposites are designed and engineered on a nanometer scale with versatile applications including optics and photonics. During the last two decades, different photopolymerizable nano-compounds were introduced and developed to modify polymer properties. In this sense, inorganic and organic nanoparticles have been introduced to increase the refractive index modulation and/or to reduce the shrinkage. Liquid crystal polymer composites have been added to the category of active photopolymer materials with an electrically switchable option. Nowadays, in the design of smart glasses some problems remain on the table, like power consumption, the limitation of the resolution, the wide field of view, etc. The inclusion of holographic optical element has provided some possible solutions. In particular the photopolymers have been reported a good system to bring the photons produced in the image creation to the eye. Our group proposed an alternative scheme using transmission holographic elements. The fabrication architecture was tested with different photopolymers in order to optimize their chemical composition, and we proposed three schemes adapted to each material properties. In this paper we study the influence of the initiator concentration, for Holographic polymer dispersed liquid crystal photopolymer, on the refractive index modulation and on the tunable properties of these holographic optical elements.

Published
2021

97. Voltage dependence of retardance, flicker, and director angle orientation in reflective liquid crystal devices by average Stokes polarimetry

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Márquez, Andrés, Martínez Guardiola, Francisco Javier, Morales-Vidal, Marta, Puerto, Daniel, Francés, Jorge, Gallego, Sergi, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Márquez, Andrés, Martínez Guardiola, Francisco Javier, Morales-Vidal, Marta, Puerto, Daniel, Francés, Jorge, Gallego, Sergi, Pascual, Inmaculada, and Beléndez, Augusto

Abstract

Parallel-aligned liquid crystal on silicon devices (PA-LCoS) can be found nowadays in most of the advanced areas in optics and photonics. Many works have been dedicated to their characterization for optimum utilization in applications. However, usual techniques are based on diffractive or interferometric measurements. Recently, we proposed the use of Stokes polarimetry for a versatile yet easy to implement characterization. We show that the LCoS can modelled as a nonabsorbent reciprocal device which, combined with time-average Stokes polarimetry, enables to demonstrate robust measurements across the whole applied voltage range for the retardance and its flicker. One of the main novelties is that we also obtain the director orientation, which we show that changes across the voltage range, especially at larger applied voltages. This might affect in very sensitive applications. It might also provide a deeper insight into the internal dynamics in the LC layer.

Published
2021

98. Tunable focal photopolymer lenses printed for the first time by laser-induced-forward transfer without a sacrificial layer

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Aix-Marseille University. CNRS, Lab Lasers Plasmas et Procédés Photoniques, Princeton University. Princeton Institute for the Science and Technology of Materials, Puerto, Daniel, Gallego, Sergi, Constantinescu, Cătălin-Daniel, Florian, Camilo, Ortuño, Manuel, Márquez, Andrés, Pascual, Inmaculada, Beléndez, Augusto, Alloncle, Anne Patricia, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Aix-Marseille University. CNRS, Lab Lasers Plasmas et Procédés Photoniques, Princeton University. Princeton Institute for the Science and Technology of Materials, Puerto, Daniel, Gallego, Sergi, Constantinescu, Cătălin-Daniel, Florian, Camilo, Ortuño, Manuel, Márquez, Andrés, Pascual, Inmaculada, Beléndez, Augusto, and Alloncle, Anne Patricia

Abstract

The fabrication of polymeric lens arrays on flexible surfaces for its use in wide-field visual systems is a challenge that is being addressed by using the Laser Induced Forward Transfer (LIFT) technique. The objective is to achieve polymer laser printing by improving both the overall printing quality and the manufacturing time of these lens matrices compared to other techniques. Another challenge when using tunable polymers is the customization of tunable focal lenses dynamically controlling their optical properties. In this work we address both aspects by using a tunable photopolymer thanks to liquid crystal molecules, such as H-PDLC.

Published
2021

99. Holographic solar concentrators stored in an eco-friendly photopolymer

Author

Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Morales-Vidal, Marta, Ramirez, Manuel G., Berramdane, Kheloud, Lloret, Tomás, Gallego, Sergi, Beléndez, Augusto, Pascual, Inmaculada, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Morales-Vidal, Marta, Ramirez, Manuel G., Berramdane, Kheloud, Lloret, Tomás, Gallego, Sergi, Beléndez, Augusto, and Pascual, Inmaculada

Abstract

In this work it is shown the first characterization of holographic solar concentrators recorded in Biophotopol - one of the greenest photopolymers. Biophotopol is an acrylate-based and water-soluble photopolymer with good recycling properties. The composition of this photopolymer and their thickness are easily changeable, which implies an important advantage vs. others commercialized photopolymers. Good diffraction efficiency and wide acceptance angles are achieved on phase volume transmission holograms by using an optimized composition and thin layers. A curing stage with a white incoherent light has been performed to obtain high temporal stability together with a good diffraction efficiency. Finally, the performance of the holographic lenses as holographic solar concentrators has been evaluated with an electronic setup connected to a polycrystalline silicon photovoltaic cell and a high intensity solar simulator emitting a standard solar spectrum (AM1.5G).

Published
2021

100. Efecto de la codificación en el número de errores introducidos en un HDSS

Author

Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Martínez Guardiola, Francisco Javier, Márquez, Andrés, Calzado Estepa, Eva María, Gallego, Sergi, Puerto, Daniel, Morales-Vidal, Marta, Pascual, Inmaculada, Beléndez, Augusto, Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Martínez Guardiola, Francisco Javier, Márquez, Andrés, Calzado Estepa, Eva María, Gallego, Sergi, Puerto, Daniel, Morales-Vidal, Marta, Pascual, Inmaculada, and Beléndez, Augusto

Abstract

En este trabajo se presentan resultados preliminares sobre el efecto de la codificación de los datos digitales introducidos en un sistema de almacenamiento holográfico de información. Para ello se introducen una serie de fuentes de ruido que afectan a las imágenes que usamos como entrada de datos. Estas fuentes de ruido son las que se observan principalmente en el montaje real, por lo que se trata de imitar la degradación del sistema para poder tener un modelo que nos ayude a identificar los parámetros más disruptivos en el tratamiento óptico de la señal y cómo influye la introducción de una codificación en dicha imagen., In this work we present preliminary results about the codification effect over the digital data introduced in a Holographic Data Storage System (HDSS). In this sense, we introduce a series of noise sources that affects to the images used as data in the system input. These noise sources are related with the different degradations that we observed in the real setup, we are trying to model the system degradation in order to obtain a computational model that helps us to indentify the more disruptive parameters in the optical signal processing and how affects the introduction of a codification in the input image.

Published
2021

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