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This paper discusses the implementation of high dynamic range in the coming generation of studio home entertainment video formats and the technical considerations that led to the adoption of a perceptually-tuned electro-optical transfer function for high dynamic range mastering and distribution. It also covers the value of display-referred systems based on a reference rendering versus historical scene-referred systems based on relative luminance and camera characteristics. [ABSTRACT FROM AUTHOR]

Polymer dispersed nano-sized liquid crystal (LC) composite which is an optically isotropic liquid crystal (OILC) has been investigated looking for its application to flexible liquid crystal displays (LCDs). In the device, nematic LC droplets with its diameter of 242nm are dispersed in polymer matrix so that the LCD has many advantages such as free touch mura, high contrast ratio, rubbing free, wide viewing angle and its phase stability with least hysteresis. However, it needs to overcome high operating voltage and low transmittance. Optimization of LC mixture and controlling ratio of LC and Polymer in the mixture to overcome such barriers are required. [ABSTRACT FROM AUTHOR]

A flash-lamp pumped electro-optically Q -switched dual-wavelength Nd:YLF laser is demonstrated. Two Nd:YLF crystals placed in two cavities are employed to generate orthogonally polarized 1047 nm and 1053 nm radiations, respectively. The two cavities are jointed together by a polarizer and share the same electro-optical Q -switch. Two narrow-band pass filters are used to block unexpected oscillations at the hold-off state of the electro-optical Q -switch. In this case, electro-optical Q -switching is able to operate successfully. With pulse synchronization realized, the maximum output energy of 66.2 mJ and 83.9 mJ are obtained for 1047 nm and 1053 nm lasers, respectively. Correspondingly, the minimum pulse width is both 17 ns for 1047 nm and 1053 nm lasers. Sum frequency generation is realized. This demonstrates the potential of this laser in difference-frequency generations to obtain terahertz wave. [ABSTRACT FROM AUTHOR]

Electro-optical imaging sensors are widely distributed and used for many different purposes, including civil security and military operations. However, laser irradiation can easily disturb their operational capability. Thus, an adequate protection mechanism for electro-optical sensors against dazzling and damaging is highly desirable. Different protection technologies exist now, but none of them satisfies the operational requirements without any constraints. In order to evaluate the performance of various laser protection measures, we present two different approaches based on triangle orientation discrimination on the one hand and structural similarity on the other hand. For both approaches, image analysis algorithms are applied to images taken of a standard test scene with triangular test patterns which is superimposed by dazzling laser light of various irradiance levels. The evaluation methods are applied to three different sensors: a standard complementary metal oxide semiconductor camera, a high dynamic range camera with a nonlinear response curve, and a sensor hardened against laser dazzling. [ABSTRACT FROM AUTHOR]

A new electro-optical chromophore with 4-(bis(2-hydroxyethyl)amino)-2,6-dipropoxybenzaldehyde as electron donor was synthesized and characterized by H NMR and mass spectra. Poly(methyl methacrylate) doped with this new chromophore at different loading densities was prepared in thermo-optical films by spin coating. These films showed low optical absorption at communication wavelength, good thermal stability and large thermo-optics coefficients. [ABSTRACT FROM AUTHOR]

Electrically detected magnetic resonance (EDMR) is a commonly used technique for the study of spin-dependent transport processes in semiconductor materials and electro-optical devices. Here, we present the design and implementation of a compact setup to measure EDMR, which is based on a commercially available benchtop electron paramagnetic resonance (EPR) spectrometer. The electrical detection part uses mostly off-the-shelf electrical components and is thus highly customizable. We present a characterization and calibration procedure for the instrument that allowed us to quantitatively reproduce results obtained on a silicon-based reference sample with a "large-scale" state-of-the-art instrument. This shows that EDMR can be used in novel contexts relevant for semiconductor device fabrication like clean room environments and even glove boxes. As an application example, we present data on a class of environment-sensitive objects new to EDMR, semiconducting organic microcrystals, and discuss similarities and differences to data obtained for thin-film devices of the same molecule. [ABSTRACT FROM AUTHOR]

This study experimentally investigated mechanical and impact performances of an alkali-activated slag (AAS) concrete reinforced with hooked-end steel fibres. The compressive, flexural and impact behaviour of AAS concrete with different volume fractions (0·0%, 0·5%, 1·0%, 1·5% and 2·0%) of steel fibre were evaluated. To examine the impact resistance of steel fibre reinforced AAS concrete, a total of 20 panel specimens (200 mm wide, 200 mm long and with a constant thickness of 50 mm) were fabricated and subjected to spherical projectile impact at velocities ranging from 150 m/s to 300 m/s measured by an electro-optical device. Projectiles of diameter 20 mm and mass 38 g were accelerated using a laboratory gas gun, and the impact resistance of the AAS concrete panels was assessed from their resistance to projectile impact in terms of average crater diameter, penetration depth and average scabbing diameter after impact testing. The main findings indicate that the addition of hooked-end steel fibres to AAS concrete improves mechanical properties such as compressive and flexural strength and impact performance. These results indicate that this new cement-less concrete may be an optimal alternative to conventional ordinary Portland cement concrete for various applications in the construction industry. [ABSTRACT FROM AUTHOR]

We report on a ferroelectric chiral smectic C (C*) phase obtained in a mixture of a nematic liquid crystal (NLC) and a chiral nonmesogenic dopant. The existence of C* phase was proven by calorimetric, dielectric and optical measurements, and also by X-rays analysis. The smectic C* which is obtained in such a way can flow, allowing to restore the ferroelectric liquid crystal layer structure in the electro-optical cells after action of the mechanical stress, as it happens with the cells filled with NLC. The proposed method of obtaining smectic C* material allows us to create innovative electro-optical cell combining the advantages of NLC (mechanical resilience) and smectic C* (high switching speed). [ABSTRACT FROM AUTHOR]

Comprehensive maritime domain awareness includes detection, tracking, and identification of vessels, and we describe work concerned with the detection and tracking elements of this problem. Millions of maritime vessels operate without the means for their positions to be independently tracked, presenting a problem for safety and security of life at sea. To date, visible wavelength imaging from space has been of limited use for vessel detection and tracking due to poor area coverage provided by individual satellites. This situation is now changing. We present a survey of currently operating spacecraft carrying electro-optical imagers offering adequate imaging resolution and commercial data availability. We model the coverage provided by 54 satellites and 85 sensors over a target area to assess the value of these assets for space-based maritime domain awareness. The results show that useful levels of coverage can now be obtained through the collective observations of existing spacecraft, although on-board resources will limit the amount of imagery that can be acquired. The launch of large numbers of high-resolution imaging nanosatellites produced by private companies will improve this coverage, and the increasing capability of small satellite platforms offers the possibility of a dedicated Electro-Optical Space-Based Maritime Domain Awareness constellation that can realise the full benefit of the concept. We propose a cooperative approach, based on cloud computing and crowdsourcing philosophies, to the operation of the ground segment and the sharing and analysis of image data, to create an effective constellation of satellites and associated data handling infrastructure that can be used to enhance maritime security, and improve the safety of lives at sea. [ABSTRACT FROM PUBLISHER]

c -axis alignment in a polymer or crystal structure has drawn attention in numerous scientific and technological applications, including crystals, thin film growth, electro-optic devices, and phase difference optics. We here demonstrate a new approach based on retardation measurement that can obtain the direction of the c -axis alignment. This is employed to visualize the three-dimensional direction of continuous crystals as a thin optical film utilizing a liquid crystal panel, using retardation analysis equipment with high resolution measurement capability. The direction of the c -axis alignment is shown so as to allow a detailed characterization of the direction perpendicular to the plane. In this analysis, the direction of the c -axis alignment is identified, and differences between molecules at inequivalent sites are quantified. The results suggest that the excellent lubrication properties of the c -axis alignment may be due to a significant localization in lateral directions. [ABSTRACT FROM AUTHOR]

Switchable polarization makes ferroelectrics a critical component in memories, actuators and electro-optic devices, and potential candidates for nanoelectronics. Although many studies of ferroelectric switching have been undertaken, much remains to be understood about switching in complex domain structures and in devices. In this work, a combination of thin-film epitaxy, macro- and nanoscale property and switching characterization, and molecular dynamics simulations are used to elucidate the nature of switching in PbZr0.2Ti0.8O3 thin films. Differences are demonstrated between (001)-/(101)- and (111)-oriented films, with the latter exhibiting complex, nanotwinned ferroelectric domain structures with high densities of 90° domain walls and considerably broadened switching characteristics. Molecular dynamics simulations predict both 180° (for (001)-/(101)-oriented films) and 90° multi-step switching (for (111)-oriented films) and these processes are subsequently observed in stroboscopic piezoresponse force microscopy. These results have implications for our understanding of ferroelectric switching and offer opportunities to change domain reversal speed. [ABSTRACT FROM AUTHOR]

In this work, BaWO nanospheres were successfully prepared by hydrothermal process. The bipolar resistive switching behavior of Ag/BaWO/FTO device is observed. Moreover, this resistive switching behavior can be modulated by white light. The device can maintain superior stability in the dark and under white-light illumination. This study is useful for developing the light-controlled nonvolatile memory devices. [ABSTRACT FROM AUTHOR]

The most commonly used commercial conducting glass is the coated SnO2:F glass substrate. However, it usually presents poor morphological properties and therefore is not adequate for solar cell applications. In this work, we report results about the morphological properties improvement of commercial conductive glass by the deposition of a SnO2 buffer layer by spray pyrolysis technique. The use of a high resistivity transparent layer (buffer) onto low resistivity transparent oxide has been found to improve the solar cell performance. The methodology for improving film morphology through the deposition of SnO2 buffer layers by spray pyrolysis technique, with appropriate electro-optical properties, is presented. The solar cell results related to the use of an automatized spray pyrolysis system are presented. [ABSTRACT FROM AUTHOR]

An electro-optic tunable device is fabricated by the incorporation of silica nanoparticles as a dopant into polymer-dispersed liquid crystal composite film followed by UV curing through polymerisation-induced phase separation process. These silica-modified fibrous aggregates of polydimethylsiloxane provide stability to the nematic liquid crystal molecules. The interaction between dispersed silica nanoparticles and modified polymer network improves the polymer/liquid crystal interface, which was successfully analysed through scanning electron microscopy. It also controlled the birefringence in nematic liquid crystal droplets and provided optical stability to the off-state (opaque) scattering of an electro-optic device. The electrical tuning of photoluminescence intensity during the stage triggering from ‘Switch OFF state’ to ‘Switch ON state’ shows dependence on the morphology of composite films. It can find out potential applications in electrically switchable shutters in display market. [ABSTRACT FROM AUTHOR]

The complex of measurements necessary for high-quality radiometric measurements of the Earth to be performed using space electrooptical instruments, including hyperspectrometric instruments, has been considered. This complex was developed in order to maintain the uniformity of measurements according to Russian legislation. In addition to organizational measures, it is necessary to determine the interrelation between radiometric data and geophysical parameters received using these data and to solve the methodological problems of the Earth observation instrument (EOI) radiometric calibration and in-orbit verification of EOI radiometric characteristics. The considered approaches are largely close to the statements of the international document 'Quality Assurance Framework for Earth Observation-QA4EO'. [ABSTRACT FROM AUTHOR]

The cis- and trans-configurational isomers of 3 are designed and investigated as chemodosimeters for CN- ions for the first time. The cis-3 reveals a NIR absorbance at 717 nm (vs. trans-3, 620 nm), and such a configurational difference can be attributed to the acidity as well as position of the binding site (CH group). A probable sensing mechanism involving cyanide-driven carbanion electron-transfer oxidation is proposed. [ABSTRACT FROM AUTHOR]

The electronic states as well as interband and intraband electrooptical transitions are considered for the narrow gap InSb nanotube in the field of homogeneously charged ring. The problem is solved in the framework of the variational approach. The field of the charged ring is brought to the field of the modified one dimensional Coulomb-like potential. Physically appropriate wave functions are suggested for this potential and the intensities of the threshold frequencies of the electrooptical transitions are calculated. [ABSTRACT FROM AUTHOR]

The article discusses physical tests undertaken by DI-Aries, an energy-mass ion spectrometer used for space research to measure the energy distribution function of ion component of plasma which was developed by Phobes-Grunt space mission by the Russian Space Agency. Topics discussed include electro-optical plan of DI-Aries, DI-Aries being tested in a automatic vacuum chamber with ion source and satisfactory value of mass and image characteristics being observed.

Blue phases-special chiral liquid crystalline mesophases-are promising candidates for electro-optic devices with improved performance and simplified fabrication. A necessary precondition for possible applications is a significantly enhanced temperature range of their existence, which can be achieved by a cross-linked polymer network formed by in situ polymerization. Unlike many other mesophases, blue phases are optically isotropic if no voltage is applied. Regarding the transmission of a blue phase cell placed between crossed polarizers, the optical isotropy enables-at least in principle-a perfect dark state, independent of the viewing angle, without the necessity of any alignment layer. The application of an in-plane electric field induces a strong birefringence (Kerr effect). The effective Kerr constants are much larger than those of isotropic liquids, and the switching times between the dark and the induced bright state are in the submillisecond range. Some basic properties of blue phases, state-of-the-art performance, and remaining challenges of the development of polymer-stabilized blue phases are reviewed in this article. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We present an experimental setup to dramatically reduce a measurement time for obtaining spatial distributions of terahertz electric-field (E-field) vectors. The method utilizes the electro-optic sampling, and we use a charge-coupled device to detect a spatial distribution of the probe beam polarization rotation by the E-field-induced Pockels effect in a (110)-oriented ZnTe crystal. A quick rotation of the ZnTe crystal allows analyzing the terahertz E-field direction at each image position, and the terahertz E-field vector mapping at a fixed position of an optical delay line is achieved within 21 ms. Video-rate mapping of terahertz E-field vectors is likely to be useful for achieving real-time sensing of terahertz vector beams, vector vortices, and surface topography. The method is also useful for a fast polarization analysis of terahertz beams. [ABSTRACT FROM AUTHOR]

In this paper, we designed the offset frequency locking and active frequency stabilization system for the continuous-wave (CW) and electro-optical Q-switched RF-excited waveguide CO2 lasers to provide an ideal light source for coherent radar. The CW laser is used as a local laser, and the pulsed laser is used as a main laser, which can produce Q-switched and cavity-dumped laser synchronously. A closed-loop laser frequency control system was used to stabilize the Q-switched laser at the gain curve center frequency and to lock the two lasers at a selected heterodyne frequency. The system includes two parts: 1) pulsed laser frequency stabilization and 2) offset frequency locking. The frequency stabilization part can keep the Q-switched laser oscillating at the peak of the gain curve by measuring the pulse build-up time continuously and controlling the cavity length. The offset frequency locking circuits keep the heterodyne frequency around the selected frequency by measuring the frequency of the beat signals and controlling the CW laser cavity length. In the experiment, the long-term frequency shift of the pulse laser was measured to be less than ±16 MHz and the offset frequency fluctuation was less than ±2 MHz when the frequency control system was in a closed-loop operation. [ABSTRACT FROM AUTHOR]

This paper describes the measurement of an organic photovoltaic using an electro-optic probe. We verify the validity of the electro-optic probe by comparing it with a conventional electric probe. The electric field distribution of the organic photovoltaic is examined on the basis of results of the test board measurement using the electro-optic probe and results of the test board simulation using an electromagnetic field simulator. We succeed in failure diagnosis of the organic photovoltaic in three failure modes. We found that the organic photovoltaic has a failure cell, and the electro-optic probe is successfully applied to failure diagnosis of organic photovoltaic. [ABSTRACT FROM AUTHOR]

A novel design of all-fiber coupled Electro-Optic (EO) sensors is introduced. Special fiber apparatus is used instead of free-space-coupling using bulk optics such as conventional lenses. The reflectance dependence on some parameters of the sensor is analyzed, such as the incident angle, the thickness of the crystal, the space between collimator and crystal, the under tested E-field, etc.. According to the analysis, the exact thickness of the LiTaO3 crystal is calculated when attached to the collimator, which can make the reflectance and sensitivity to maximum. [ABSTRACT FROM AUTHOR]

Liquid-crystalline polymers are materials of considerable scientific interest and technological value. An important subset of these materials exhibit rubber-like elasticity, combining the optical properties of liquid crystals with the mechanical properties of rubber. Moreover, they exhibit behaviour not seen in either type of material independently, and many of their properties depend crucially on the particular mesophase employed. Such stretchable liquid-crystalline polymers have previously been demonstrated in the nematic, chiral-nematic, and smectic mesophases. Here, we report the fabrication of a stretchable gel of blue phase I, which forms a self-assembled, three-dimensional photonic crystal that remains electro-optically switchable under a moderate applied voltage, and whose optical properties can be manipulated by an applied strain. We also find that, unlike its undistorted counterpart, a mechanically deformed blue phase exhibits a Pockels electro-optic effect, which sets out new theoretical challenges and possibilities for low-voltage electro-optic devices. [ABSTRACT FROM AUTHOR]

This paper measures the dielectric constant and loss tangent of methacryloyloxy–propyltrimethoxysilane (MAPTMS) sol-gel films over a wide range of microwave frequencies. Samples were prepared by spin-coating sol-gel films onto metallized borosilicate glass substrates. The dielectric properties of the sol-gel were probed up to 50 GHz with several different sets of coplanar waveguide transmission lines electroplated onto sol-gel films. The dielectric constant and loss tangent are determined to be approximately 3.1 and \3\times \10^-3 at 35 GHz, respectively. This demonstration shows that MAPTMS sol-gel is a viable material for integration with high-speed electrical and electrooptic devices. [ABSTRACT FROM PUBLISHER]

The representative recent works of us, Optical Single Crystals Group, NIMS, Japan, are reviewed. Our group has been working on the development of novel single crystals for electro-optical applications based on the Czochralski technique. Here, 3 kinds of topics are reviewed. 1st one is transparent conductive β- single crystals as semiconductor, which has quite large bandgap, 4.8 eV, for LED and power device applications. 2nd one is a new concept of phospher material, single-crystal phospher, based on Y3AI5O12 single crystal. These single-crystal phosphers are promising for highly efficient, resin-free, high brightness white LEDs/LDs. 3rd one is superior magneto-optical single crystals for optical isolators. {Tb3}[Sc2-xLux](Al3)Oi2 single crystals for near infrared to visible region, and CeF3/PrF3 single crystals for UV region are realized. [ABSTRACT FROM AUTHOR]

A novel differential technique of femtoseconds pump-probe laser beam to test energy transport properties of nanomaterials, based on an electro-optic device, is presented. As opposed to the standard methods, ours allows the modulation of the probe-beam. As will be shown, the differential method overcomes the drawbacks of the existing technologies for nanomaterials. These drawbacks includes the time resolution of the collected data, the signal to noise ratio and the time to record the reflectance data. [ABSTRACT FROM AUTHOR]

The detection of solar neutrinos by means of a liquid scintillator requires very low levels of radioactivity throughout the whole active volume. The selection of clean detector materials and the purification of the scintillator are necessary, but not sufficient conditions. It is also crucial that during the filling operations the scintillator is not contaminated, either by air or by getting in contact with dirty surfaces. This paper describes the procedures which we adopted to minimize these risks and achieve very good levels of radio-purity which we finally got in Borexino. [ABSTRACT FROM AUTHOR]

A fundamental breakthrough which opened the way to the realization of the Borexino detector was the demonstration of exceptionally low, unprecedented radioactive contaminations in the liquid scintillator, obtained with its pilot prototype Counting Test Facility. Though of limited dimension, with its 4.8 m3 of active liquid core, CTF has however been a key milestone not only for Borexino, but also for the entire field of the ultra-low background searches. Here, we succinctly remind the motivations, which concurred to lay down the project, as well as the specific radiopurity challenge, which guided the design. After the description of the technical elements of the detector, the main outcomes are summarized, both regarding optical and purity scintillator properties, with special emphasis on the exceptional achievements in term of ultra-low traces of radioactive contaminants. The discussion is completed with the description of how CTF was employed for the pre-qualification of the entire inventory of the Borexino scintillator, confirming also in the final phase of its life its essential role for the success of the overall Borexino solar neutrino program. [ABSTRACT FROM AUTHOR]

Laser-induced ripples or uniform arrays of continuous near sub-wavelength or discontinuous deep sub-wavelength structures are formed on single-crystalline silicon (Si) by femtosecond (fs) laser direct writing technique. Laser irradiation was performed on Si wafers at normal incidence in air and by immersing them in dimethyl sulfoxide using linearly polarized Ti:sapphire fs laser pulses of ~110 fs pulse duration and ~800 nm wavelength. Morphology studies of laser written surfaces reveal that sub-wavelength features are oriented perpendicular to laser polarization, while their morphology and spatial periodicity depend on the surrounding dielectric medium. The formation mechanism of the sub-wavelength features is explained by interference of incident laser with surface plasmon polaritons. This work proves the feasibility of fs laser direct writing technique for the fabrication of sub-wavelength features, which could help in fabrication of advanced electro-optic devices. [ABSTRACT FROM AUTHOR]

Most active-matrix FLC (AMFLC) devices were mainly realized in the form of LCOS display rather than in the TFT platform. This is because FLC devices normally require higher power and current to drive due to the larger pixel capacitance inhering from the small cell gap. Difficulty in generating grayscale also poses great challenge in commercializing AMFLC. We proposed a new TFT pixel design incorporating ESH FLC mode and BGTFT that successfully demonstrated AMFLC display with grayscale while preserving FLC's fast switching property. [ABSTRACT FROM AUTHOR]

This paper consists of two Parts. In the Part 1, we report the experimental results and considerations of the reduction of operation voltage and response time of narrow-gap TN(NTN)-LCDs embedded with the nanoparticles of hydrophobic Aerosil silica. While, in the Part 2, we give a report of the reduction of response time, especially τofffor the decay process of optically compensated tunable birefringence (OCTB)-mode LCD. [ABSTRACT FROM PUBLISHER]

Abstract: We synthesized three new donor-modified push–pull chromophores with the same divinylenethiophenyl bridge and tricyanofuran acceptor, but with different modified donor moieties. Structure analysis and photophysical properties were carried out to compare the molecular mobility and steric hindrance effect of different donor-modified chromophores. Density functional theory calculations and thermal properties showed the different results of chromophores' microscopic nonlinearity and thermal stability. In electro-optic activities, the poling process demonstrated that guest–host electro-optic polymers containing the chromophores with different steric hindrance and molecular free mobility, required different optimal poling condition to achieve the large macroscopic electro-optic coefficients. After the exploration of the poling condition, it showed an ultra large electro-optic coefficient (266 pm/V) for electro-optic polymer WJ5-APC-2, which indicated the fine-tuning of steric hindrance and molecular free mobility of chromophore WJ5 in host polymer APC-2. Meanwhile, steric hindrance also improved the temporal stability of electro-optic coefficients for WJ5-APC-2. [Copyright &y& Elsevier]

In this paper we illustrate the ability of electrooptic sensors to perform electric (E)-field vectorial measurements. Thanks to their frequency response spreading over nine decades and to their measurement dynamics reaching 120 dB, these sensors are of high interest for some applications (near field mapping, energy line monitoring, electromagnetic compatibility, and so on). Furthermore, due to their fully dielectric structure and millimetric size, almost no perturbation is induced on the E-field to be measured, even in the near field region. This paper is focused on high-intensity pulsed E-field characterization in different environments such as air, water (bioelectromagnetism applications), or plasmas (in situ assessment of the E-field associated to an electric discharge and to the induced plasma). The use of such a technology for electrical equipment and energy line monitoring is also investigated. [ABSTRACT FROM PUBLISHER]