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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. Work funded by Generalitat Valenciana (Spain) (PROMETEO/2021/006, IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme GV/2019/021); and Universidad de Alicante (Spain), projects GRE17-06 and UATALENTO 18-10.

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. This work was supported by the “Generalitat Valenciana” of Spain (projects PROMETEO/2021/006 and IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme) and by the Universidad de Alicante, Spain (UATALENTO18-10; ACIE-20-10).

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. The work was supported by Generalitat Valenciana (projects PROMETEO/2021/006; IDIFEDER/2021/014, cofunded by European Union through the FEDER programme).

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).

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).

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).

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.

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).

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.

In this work we present a study of Holographic waveguides recorded in photopolymers. The holographic waveguides presented in this work are created by recording two holograms in a glass substrate; the first hologram acting as an in-coupler element, and the second hologram acting as an out-coupler element.

Nowadays, wearable eyeglasses and waveguides are one of the most promising applications in photonics for the holographic recording materials. Holographic techniques structures together with the optimized recording materials permit the fabrication of the high resolution structures. In the applications of see-through glasses, the light signal can be generated on the back of the human head and guided along the temples of the glass to the frontal lenses and redirected to the eye. Therefore, we need two wave-couplers, W-C, one to trap the light inside the temples, and second in the lenses one to redirect the guide light into the eye. The holography gives us a possibility when we store the holographic optical element, HOE, with a determinate wavelength and we use the display with a longer one. Our proposal is fabricating this wave-couplers for normal light incidence using photopolymers, as recording material, because we can self-fabricate them and modify their composition and optical properties. We fabricate the HOE using a 532 nm laser to guide the 632 nm light. Furthermore, in this work we present the results obtained with different family of photopolymers. This work was supported by the “Ministerio de Ciencia, Innovación y Universidades” (Spain) under projects FIS2017-82919-R (MINECO/AE/FEDER, UE) and FIS2015-66570-P (MINECO/FEDER). R.F. and M.M-V. acknowledge the financial support by the "Generalitat Valenciana” (Spain) under grants APOSTD/2018/084 and CDEIGENT/2018/024, respectively.

Innovative technologies demand versatile and environmentally compatible optical elements. In this paper we evaluated the quality of volume phase transmission lenses stored in a biocompatible photopolymer. Holographic lenses (HL) have been obtained with the same focal and diameter, for a symmetric and asymmetric experimental setups, and positive and negative focal. The quality of these lenses have been evaluated: theoretically and experimentally, from the calculation of the modulation transfer function (MTF) by capturing the point spread function (PSF) with a CCD sensor. The HLs that have shown better quality are the negative asymmetrically recorded compared with the theoretical ones. Ministerio de Economía, Industria y Competitividad (Spain) (FIS2017-82919-R and FIS2015-66570-P); Generalitat Valenciana (Spain) (PROMETEO II/2015/015; Universidad de Alicante Ayuda AII2017-12.

Notwithstanding his important scientific contributions, Sommerfeld never received the Nobel Prize in Physics, although he was responsible for a series of major achievements that amply justified the award, and also created several records related to the prize that would be very hard to beat: He is the physicist with highest number of doctoral students who were awarded a Nobel prize, namely four (Werner Heisenberg, Wolfgang Pauli, Peter Debye and Hans Bethe). He received the most nominations for the Nobel Prize in Physics, specifically 84 between 1917 and 1951 (more than any other physicist, including Otto Stern, who comes second with 82 nominations, but who was eventually awarded the prize). In 1929 he received nine nominations, including those of three Nobel Prize winners in Physics: Max Planck, James Franck and Max von Laue.

André-Marie Ampère (1775-1836) showed a great capacity for mathematics and worked on optics and chemistry. In fact, he can be considered almost an important chemist. Although he made contributions of some importance in mathematics (algebra, mathematical analysis and calculation of probabilities), undoubtedly his greatest contribution was made in the area of electromagnetism, at the age of 45 years. In 1826 he published “The Mathematical Theory of Electrodynamic Phenomena Deduced Solely from Experiment”, a book in which he states that “magnetism is electricity in motion” and “magnetic phenomena depend only on the existence and motion of electrical charges”.

This work was supported by the "Ministerio de Economía y Competitividad" (projects FIS2014-56100-C2-1-P y FIS2015-66570-P), by the "Generalitat Valenciana" (projects PROMETEOII/2015/015 and ISIC/2012/013) and by the "Universidad de Alicante" (project GRE12-14).

On June 13, but in 1831 the Scottish physicist James Clerk Maxwell was born. In 1865, one hundred and fifty years ago, he published an article titled A Dynamical Theory of the Electromagnetic Field, which not only included the electromagnetic field equations (today known as «Maxwell’s equations»), but also predicted the existence of electromagnetic waves moving at the speed of light, and presented the electromagnetic theory of light. In this article he stated: «it seems we have strong reason to conclude that light itself (including radiant heat, and other radiations if any) is an electromagnetic disturbance in the form of waves propagated through the electromagnetic field according to electromagnetic laws». He was not wrong. Then, in 2015, we celebrate the 150th anniversary of the electromagnetic theory of light, which is one of the milestones commemorated in the International Year of Light and Light-Based Technologies (IYL 2015).

In this work the split-field finite-difference time-domain method (SF-FDTD) applied to the analysis of two-dimensionally periodic structures is accelerated for Intel Xeon Phi coprocessors and NVIDIA GPUs platforms. The performance achieved by the novel Intel coprocessors is compared with GPU computing and the sequential code optimized by the compiler and parallelized by means of OpenMP in a single CPU with several cores. The results show that in all cases the CUDA version of the 3D SF-FDTD algorithm is more than thirteen times faster compared to the sequential code and until three times faster compared to the Intel Xeon Phi coprocessor. It is worth to note that the speed up obtained by the Intel Xeon Phi coprocessor is achieved using the sequential code of the CPU program since it is based on the Intel Many Integrated Core (MIC) architecture. Therefore, the time costs needed for launching applications on Intel Xeon Phi coprocessors are dramatically reduced compared to the efforts needed for developing CUDA codes compatible with the NVIDIA GPUs. This work was supported by the “Ministerio de Economía y Competitividad” of Spain under project FIS2011-29803-C02-01, by the “Generalitat Valenciana” of Spain under projects ISIC/2012/013 and GV/2014/076, and by the "Universidad de Alicante" of Spain under project

On 20 December 2013, the United Nations General Assembly 68th Session proclaimed 2015 the International Year of Light and Light-based Technologies (IYL 2015) to highlight the fundamental role of light and its technologies in all human activities. Light is at the origin of life, it has inspired beauty, painters, poets, architects… and is essential to photography, cinema, theatre or television because there is no doubt that light affects the emotional response of the audience. We just need to look around us to verify that the numerous applications of light in science, engineering, architecture, medicine, communications, culture, art and leisure have revolutionized society.

Este trabajo ha sido financiado por el Ministerio de Economía y Competitividad (FIS2011-29803-C02-01 y FIS2011-29803-C02-02) y por la Generalitat Valenciana (PROMETEO/2011/021, ISIC/2012/013).

The work was supported by the “Ministerio de Economía y Competitividad” of Spain under projects FIS2011-29803-C02-01 and FIS2011-29803-C02-02 and by the “Generalitat Valenciana” of Spain under projects PROMETEO/2011/021 and ISIC/2012/013.

Parallel-aligned liquid crystal on silicon (PA-LCoS) displays have become the most attractive spatial light modulator device for a wide range of applications, due to their superior resolution and light efficiency, added to their phase-only capability. Recently we proposed a novel polarimetric method, based on Stokes polarimetry, enabling the characterization of their linear retardance and the magnitude of their associated phase fluctuations, if existent, as it happens in most of digital backplane PA-LCoS devices. In this work we describe the characterization technique together with its predictive capability, and we show some experimental analysis we have performed to delimitate its robustness dealing with the repeatibility and reproducibility of the technique. The calibrated retardance and phase fluctuation values can then be used to estimate the performance of the PA-LCoS device in applications, such as in diffractive optics. Work supported by Min. de Trabajo y Competitividad of Spain (projects FIS2011-29803-C02-01 and FIS2011-29803-C02-02), by Gen. Valenciana of Spain (projects PROMETEO/2011/021 and ISIC/2012/013), and by Universidad de Alicante (project GRE12-14).

This work pretends to optimize the standard composition of the PVA/Acrylamide photopolymer, changing its composition in order to improve its spatial resolution. To do this, a chain transfer agent, 4,4'-azobis (4-cyanopentanoic acid) (ACPA) was introduced in the photopolymer and its concentration was modified. Thus, the optimal concentration which gets obtain the maximum diffraction efficiency for high spatial frequencies was found. To quantify the improvement that occurs with the inclusion of the ACPA in the PVA/Acrylamide photopolymer, holographic reflexion gratings of 4553 lines/mm were stored. Moreover, diffraction efficiency obtained with the different concentrations of ACPA was measured to compare the obtained results. This work was supported by the “Generalitat Valenciana” (Spain) under project PROMETEO/2011/021, ISIC/2012/013 and GV/2012/099 and by “Ministerio de Ciencia e Innovación” (Spain) under projects FIS2011-29803-C02-01 and FIS2011-29803-C02-02.