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Conventional approaches for designing metasurfaces with the desired scattering response are often a time‐consuming and onerous process that heavily relies on the design experience and empirical methods. In this paper, a time and resource‐efficient design method is proposed for the synthesis of multiple metasurface polarizers with an efficient automated data generation process by utilizing the structure validation surrogate model (SVSM). Moreover, a novel attention and space‐to‐depth enhanced adaptive tandem network (ASE‐ATN) is proposed which integrates symmetry‐aware space‐to‐depth (SA‐SPD) along with the attention mechanism for efficient feature extraction. Several design examples of metasurfaces with linear polarization to orthogonal linear polarization (LP‐OLP) and/or linear polarization to circular polarization (LP‐CP) conversion capabilities are provided to verify the performance of the proposed method. The feasibility of the proposed method is demonstrated through the fabrication and measurement of a dual‐band dual‐polarization converter. [ABSTRACT FROM AUTHOR]

The manipulation of electromagnetic waves using metasurfaces is important in areas such as stealth and communication. In this paper, we reported on the use of an element-based polarizer for the first step, which enables the incident electromagnetic waves to integrate into the cross-polarized waves with a relative bandwidth of 88% within 15–37.1 GHz. Then, an eight-element coding metasurface based on the Pancharatnam–Berry phase is presented for circular polarization anomalous reflection. The simulated values show that our work can achieve a high-efficiency (94%) and wide-angle (70°) anomalous reflection under normal incidence. The simulated values present good agreement with the experimental values. Our work reveals the ability to manipulate the waves and electromagnetic stealth. [ABSTRACT FROM AUTHOR]

A fiber-based surface plasmon resonance (SPR) sensor is investigated in this study. Initially, a D-shaped optical fiber is studied under different types and brands of light sources, optical spectrometers, and polarizing angles. The best stability with low noise is a supercontinuum light source with Avantes spectrometer. Using the polarizer controller to tune the width and dip shows the minimum absorption point when waveplates are set at 90°, 0°, and 45°. The temperature effects are recognized as shifts in absorption ranging from 30 to 60 °C for fiber-based SPR (with and without a polarizer controller). In the photoelastic effect, the sensor shows significant variation according to the applied load, with a maximum sensitivity of 1.05 nm/g at 5 g weight. Stability, response time, and selectivity are also discussed. Results are used to analyze the plasmonic sensor efficiency for Hg ions detection. It appears that there is a lack of information regarding the light types and polarization angles within a D-shaped fiber for Hg ions SPR sensor. As of now, there seems to be no published literature that has thoroughly explored this topic under different conditions. [ABSTRACT FROM AUTHOR]

This study presents the development of ultra‐thin azo‐dye polarizers, notable for their minimal thickness (100‐200 nm) and superior optical performance, with polarization efficiency exceeding 99.9%, extinction ratios above 4000, transmittance over 45.3%, and dichoric ratio over 100. Utilizing cost‐effective solution‐processing methods, we fabricate these high‐performance polarizers and determine optimal experimental conditions for peak efficacy. Our research includes comprehensive Scanning Electron Microscopy analyses to understand the microstructural properties of these azo‐dye thin film polarizers, contributing significantly to the field of advanced display technologies. [ABSTRACT FROM AUTHOR]

We have developed a new polarizer system named "Light Control Polarizer (LCP)" that has a shading effect comparable to that of light control films (LCF) while significantly improving on‐axis luminance loss. The LCP exhibits a louver effect of 1.4% at a 60° polar angle and 1.1% at a ‐60° polar angle in vertical direction, with a 20% increase in on‐axis luminance over LCF and a 12% increase in contrast ratio (CR). These characteristics allow the LCP to work as an alternative to LCF providing with effective light shielding in the vertical direction without sacrificing display luminance. [ABSTRACT FROM AUTHOR]

This paper presents a novel wideband low-profile linear-to-circular polarizer based on high refractive-index metamaterials in the X band. The proposed design is a multilayer structure that is built from two kinds of metamaterial unit cells consisting of 4-H-shaped strips and 1-H-shaped strips. Combining the two unit cells realizes the flexible and independent control of the refractive index difference between two orthogonal E-field components and thus achieves a consistent 90-degree phase delay over a wide bandwidth. Moreover, the proposed unit cell shows a high refractive index, which contributes to lowering the height of the LP-CP polarizer. In order to improve the axial ratio (AR) bandwidth, two impedance-matching layers are introduced to combat the reflection loss on the metamaterial-air boundary. Nevertheless, the proposed design can provide a wide 3 dB AR bandwidth of 37.7% and a low insertion loss of 0.5 dB with a thin profile of $0.21~{\lambda }_{0}$ . The prototype was fabricated and measured, while the experimental results agree well with the simulated ones, thus validating the working mechanism and its practical feasibility.

In fields such as polarization navigation and imaging, there is a demand for polarizers to simultaneously possess a high transmittance and extinction ratio. However, most studies focus solely on a single metric for polarizer design. To address this issue, this paper proposed a metasurface polarizer with a transition layer and its efficient design method, aiming to enhance the polarizers' transmittance and extinction ratio performance simultaneously. An all-dielectric metasurface polarizer with a TiO2 transition layer was designed, and a tandem neural network was constructed by combining forward prediction and inverse design networks. The network is successfully trained by utilizing structural parameters and spectral response Tx and Ty datasets collected through simulation software. A high-performance metasurface polarizer was designed under the desired metrics with a transmittance of 90% and an extinction ratio of 40 dB. The proposed method in this paper made progress in the comprehensive optimization of polarizer performance. It is more accurate and efficient compared to other design methods and is better suited for practical applications. [ABSTRACT FROM AUTHOR]

The polarizer film is an important component in the Thin-film-transistor liquid crystal displays (TFT-LCDs), which is a multilayer composite film developed by using dichromatic material stretching film technology. However, the polarizer film is liable to fail in hygrothermal circumstances. In this work, we analyzed a polarizer film shipped from China to Brazil that failed due to the ocean environment. By analyzing the structure, composition, and crystallinity of the polarizer film, Polyvinyl Alcohol (PVA) layer of the polarizer film has larger crystallinity, and there are bonding pores between the PVA layer and the Triacetyl Cellulose (TAC) layer. Under the action of the marine environment, the I3− ions in the PVA layer were released, resulting in the separation of PVA layer and TAC layer at the bonding pores, and then forming bright spots. Furthermore, through analyzing the marine environment and simulated environmental experiments, it was determined that the thermal environmental factor induces the release of I3− ions in the PVA layer. Finally, based on the failure process and failure mechanism of the polarizer, improvement measures to prevent the occurrence of bright spots of the polarizer are proposed. [ABSTRACT FROM AUTHOR]

We unveil a highly efficient circular polarizer based on twisted double Td − WTe2 thin film in the transmissive and reflective modes. This polarizer can transform a linearly polarized incident wave into a circularly polarized one with extremely high extinction ratios by simply adjusting the orientation of the incident polarization plane. The proposed structure provides switching between the right-handed and left-handed circular polarizations (RCP and LCP) in the output wave by tuning the frequency and, in particular, the polarization direction of the incident wave. Furthermore, the twist angle of the thin films can control the handedness of the converted wave to be either LCP or RCP. Owing to the high efficiency of the polarization conversion and accessibility of the realization of the proposed structure, it may have potential applications as a polarization manipulator in the optical sensing, communication, and defense industry.

Summary: This paper proposed the design of a broadband linear‐to‐circular reflecting polarizer for X‐band applications. The polarizer is designed with three‐arm dipole‐shaped unit cells with a full ground plane to get wideband performance. The incident linear polarized wave is converted to a right‐handed circularly polarized wave upon reflection from the polarizer. The footprint of the unit cell is 9 × 9 mm, which is printed on a FR‐4 substrate. Fabricated prototype is measured for its performances like polarization conversion ratio (PCR), fractional bandwidth, and aperture efficiency. The PCR is about 97%, and the fractional bandwidth is 64% with the aperture efficiency of more than 80%. Polarizer performance is analyzed in transverse electric and transverse magnetic modes, and they are stable up to 40° of various incident angles. The polarizer exhibits the 3‐dB axial ratio bandwidth from 8 to 12 GHz, which is suitable for satellite applications. [ABSTRACT FROM AUTHOR]

Metasurfaces, composed of micro-nano-structured planar materials, offer highly tunable control over incident light and find significant applications in imaging, navigation, and sensing. However, highly efficient polarization devices are scarce for the extended shortwave infrared (ESWIR) range (1.7~2.5 μm). This paper proposes and demonstrates a highly efficient all-dielectric diatomic metasurface composed of single-crystalline Si nanocylinders and nanocubes on SiO2. This metasurface can serve as a nanoscale linear polarizer for generating polarization-angle-controllable linearly polarized light. At the wavelength of 2172 nm, the maximum transmission efficiency, extinction ratio, and linear polarization degree can reach 93.43%, 45.06 dB, and 0.9973, respectively. Moreover, a nonpolarizing beam splitter (NPBS) was designed and deduced theoretically based on this polarizer, which can achieve a splitting angle of ±13.18° and a phase difference of π. This beam splitter can be equivalently represented as an integration of a linear polarizer with controllable polarization angles and an NPBS with one-bit phase modulation. It is envisaged that through further design optimization, the phase tuning range of the metasurface can be expanded, allowing for the extension of the operational wavelength into the mid-wave infrared range, and the splitting angle is adjustable. Moreover, it can be utilized for integrated polarization detectors and be a potential application for optical digital encoding metasurfaces. [ABSTRACT FROM AUTHOR]

It has been established that in order to obtain a high-quality image of a surface structure in polarized light with crossed nicols and to accurately quantify the bainitic fraction in Kh2G2S2MF grade structural steel, alongside with the LePera reagent, Nital reagent can be used. It has been established that the brightness level of martensite in polarized light does not depend on the etching time of 22Kh2G2S2MF and 44Kh2G2S2MF grade steel being at the background level. [ABSTRACT FROM AUTHOR]

Pancharatnam—Berry (PB) phase metasurface, as a special class of gradient metasurfaces, has been paid much attention owing to the robust performance for phase control of circularly polarized waves. Herein, we present an element-based polarizer for the first step, which enables the incident electromagnetic waves into the cross-polarized waves with the relative bandwidth of 71%, and the polarization conversion ratio exceeds 90% at 6.9–14.5 GHz. Then an eight-elements coding polarizer based on the PB phase is presented for the applications on beam control and radar cross section reduction. The simulated values indicate that the reduction of radar cross section is more than 10 dB at 6–16 GHz. Our work reveals the availability of manipulating the waves, beamforming in communication systems and electromagnetic stealth, and so on. [ABSTRACT FROM AUTHOR]

A new polarizer system has been developed to improve the light efficiency and on‐axis contrast of LCDs by reflecting and recycling oblique light. The new polarizer system realizes an 8% increase in on‐axis brightness and on‐axis contrast. [ABSTRACT FROM AUTHOR]

Optical isolation with high-quality, large-aperture polarizers is commonly used in high-power laser facilities to suppress retro-reflected pulses. However, it is hard to manufacture these polarizers. We propose an approach of optical isolation with two plasma-electrode Pockels cells instead of large-aperture polarizers. In this approach, Nd:glass slabs placed at the Brewster′s angle are used as polarizers. The analysis results and the application performances in the Xingguang (Star Light) XG-III PW beamline indicate that this approach can supply good protection to optical components in laser facilities.

This work demonstrates a novel, reflective-type, dual-polarized multiband polarization transformer for various C to Ku band applications. The design constitutes a top FSS printed on a thin FR-4 grounded dielectric substrate. A y / x -polarized incident wave experiences linear-circular conversion from 4.61 to 4.71 GHz (right-hand circular polarized (RHCP)/left-hand circular polarized (LHCP)), 5.44 to 7.68 GHz (LHCP/RHCP), 10.13 to 14.98 GHz (RHCP/LHCP), and 16.68 to 17.19 GHz (LHCP/RHCP) with 3.41, 34.15, 38.63, and 3.01% FBW, respectively. In addition, it performs linear-cross conversions with a minimum 90% polarization conversion ratio (PCR) from 4.92 to 5.18 GHz, 8.32 to 9.41 GHz, and 15.56 to 16.25 GHz with 5.15, 12.30, and 4.34% FBW. Multiple surface plasmonic resonances are responsible for these polarization conversions in different bands. The device performance is angular stable for both transverse electric (TE) and transverse magnetic (TM) incidences. The design novelty lies in compacted periodicity 0.112 λL , low-profile thickness 0.037 λL with a multi-conversion (switching the orthogonal circular rotation in consecutive bands), and stable angular response, which can potentially be used in real-time applications. [ABSTRACT FROM AUTHOR]

We propose an original technique for the grating metasurfaces fabrication by low-power ultraviolet laser treatment of fluorinated graphene (FG) films with the focus on terahertz applications. The laser treatment reduces dielectric FG to its conductive counterparts, increasing DC conductivity to 170 S·m−1 for treated areas. The electromagnetic response of the grating metasurfaces studied by THz time-domain spectroscopy in the 100 GHz–1 THz frequency range demonstrates enhanced resonant transmittance through metasurfaces. The intensity and position of transmittance peak could be tuned by changing the metasurface geometry, i.e. the period of the structure and width of the reduced and unreduced areas. In particular, the decrease of the reduced FG area width from 400 to 170 μ m leads to the shift of the resonance peak from 0.45 THz to the higher frequencies, 0.85 THz. Theoretical description based on the multipole theory supported by finite element numerical calculations confirms the excitation of the dark state in the metasurface unit cells comprising reduced and unreduced FG areas at resonance frequency determined by the structure geometrical features. Fabricated metasurfaces have been proved to be efficient narrowband polarizers being rotated by 50° about the incident THz field vector. [ABSTRACT FROM AUTHOR]

In this paper, we present an ultra-wideband linear-polarization converter with excellent efficient asymmetric transmission characteristics. Numerical simulations present that the polarization conversion ratio is greater than 0.9 at 4.6 - 14.0 GHz and its asymmetric transmission parameter reaches 0.7 at the same frequency region. The microwave experiment is performed to prove the simulations, and the experimental results coincide with the simulation results. The mechanisms of polarization conversion and asymmetric transmission are explained by distributions of surface current and electric field. The superposition of multiple resonances broadens the bandwidth. We believe that our work is of great significance to potential applications for manipulating electromagnetic waves. [ABSTRACT FROM AUTHOR]

In this paper, a sandwiched polarizer with three-layer dielectric structure under Littrow mounting is proposed. Rigorous coupled-wave analysis is used to optimize the parameters of the polarizer structure. In addition, modal method is added in this research to investigate the precise process of energy coupling in the grating. With the incidence wavelength of 800 nm, high efficiencies of 99.5% for TE polarization and 99.1% for TM polarization can be achieved under the optimal grating parameters. The presented novel high-efficiency polarizer has certain application value in optical fiber communication and laser system. [ABSTRACT FROM AUTHOR]

Optical isolation with high-quality, large-aperture polarizers is commonly used in high-power laser facilities to suppress retro-reflected pulses. However, it is hard to manufacture these polarizers. We propose an approach of optical isolation with two plasma-electrode Pockels cells instead of large-aperture polarizers. In this approach, Nd:glass slabs placed at the Brewster′s angle are used as polarizers. The analysis results and the application performances in the Xingguang (Star Light) XG-III PW beamline indicate that this approach can supply good protection to optical components in laser facilities. [ABSTRACT FROM AUTHOR]

In fields such as polarization navigation and imaging, there is a demand for polarizers to simultaneously possess a high transmittance and extinction ratio. However, most studies focus solely on a single metric for polarizer design. To address this issue, this paper proposed a metasurface polarizer with a transition layer and its efficient design method, aiming to enhance the polarizers’ transmittance and extinction ratio performance simultaneously. An all-dielectric metasurface polarizer with a TiO2 transition layer was designed, and a tandem neural network was constructed by combining forward prediction and inverse design networks. The network is successfully trained by utilizing structural parameters and spectral response Tx and Ty datasets collected through simulation software. A high-performance metasurface polarizer was designed under the desired metrics with a transmittance of 90% and an extinction ratio of 40 dB. The proposed method in this paper made progress in the comprehensive optimization of polarizer performance. It is more accurate and efficient compared to other design methods and is better suited for practical applications.

Polarimetry is a highly sensitive method to quantify changes of the polarization state of light when passing through matter and is therefore widely applied in material science. The progress of synchrotron and X-ray free electron laser (XFEL) sources has led to significant developments of X-ray polarizers, opening perspectives for new applications of polarimetry to study source and beamline parameters as well as sample characteristics. X-ray polarimetry has shown to date a polarization purity of less than 1.4x10-11, enabling the detection of very small signals from ultrafast phenomena. A prominent application is the detection of vacuum birefringence. Vacuum birefringence is predicted in quantum electrodynamics and is expected to be probed by combining an XFEL with a petawatt-class optical laser. We review how source and optical elements affect X-ray polarimeters in general and which qualities are required for the detection of vacuum birefringence. [ABSTRACT FROM AUTHOR]

Metasurface that features flexible capability of light intensity modulation is widely applied to generate grayscale nanoprinting. To encode multiple grayscale nanoprintings into a single metasurface, different settings of analyzers are typically required. Here, a wavelength-multiplexed metasurface with no need of analyzer is proposed to realize a dual-channel continuous grayscale nanoprintings. The proposed metasurface is composed of two layers of nanobricks (NBs), where each layer of NBs independently acts as a polarizer under the light illumination at two selected wavelengths. By tailoring the orientation angles of NBs, distinct continuous grayscale nanoprintings with high fidelity and no crosstalk are encoded into two wavelength-dependent channels. Meanwhile, the proposed configuration can still generate the same high-quality nanoprintings with a large misalignment appearing between two layers of NBs, possessing outstanding structural robustness. The proposed wavelength-multiplexed strategy offers new insights into multi-channel display and paves the way for low-crosstalk display, high-density optical information storage and optical encryption. • A wavelength-multiplexed metasurface is proposed to realize a dual-channel continuous grayscale nanoprintings. • Each layer of nanobricks independently acts as a polarizer under the light illumination at two selected wavelengths. • By tailoring the orientation angles of nanobricks, distinct grayscale nanoprintings are encoded into two channels. • Meanwhile, the proposed configuration possesses outstanding structural robustness. • The proposed strategy offers new insights into multi-channel display. [ABSTRACT FROM AUTHOR]

Metasurfaces, composed of micro-nano-structured planar materials, offer highly tunable control over incident light and find significant applications in imaging, navigation, and sensing. However, highly efficient polarization devices are scarce for the extended shortwave infrared (ESWIR) range (1.7~2.5 μm). This paper proposes and demonstrates a highly efficient all-dielectric diatomic metasurface composed of single-crystalline Si nanocylinders and nanocubes on SiO2. This metasurface can serve as a nanoscale linear polarizer for generating polarization-angle-controllable linearly polarized light. At the wavelength of 2172 nm, the maximum transmission efficiency, extinction ratio, and linear polarization degree can reach 93.43%, 45.06 dB, and 0.9973, respectively. Moreover, a nonpolarizing beam splitter (NPBS) was designed and deduced theoretically based on this polarizer, which can achieve a splitting angle of ±13.18° and a phase difference of π. This beam splitter can be equivalently represented as an integration of a linear polarizer with controllable polarization angles and an NPBS with one-bit phase modulation. It is envisaged that through further design optimization, the phase tuning range of the metasurface can be expanded, allowing for the extension of the operational wavelength into the mid-wave infrared range, and the splitting angle is adjustable. Moreover, it can be utilized for integrated polarization detectors and be a potential application for optical digital encoding metasurfaces.

Two-dimensional (2D) materials exhibit fascinating and outstanding optoelectronic properties, laying the foundation for the development of novel optoelectronic devices. However, ultra-weak light absorption of 2D materials limits the performance of the optoelectronic devices. Here, a structure of MoS2/graphene/Au integrated onto the side-polished fiber (SPF) is proposed to achieve a high-performance fiber-integrated multifunction-in-one optoelectronic device. It is found that the device can absorb the transverse magnetic (TM) mode guided in the SPF and generate photocurrents as a polarization-sensitive photodetector, while the transverse electric (TE) mode passes with low loss through the device, making the device simultaneously a polarizer. In the device, the MoS2 film and the Au finger electrode can enhance the TM absorption by 1.75 times and 24.8 times, respectively, thus allowing to achieve high performance: a high photoresponsivity of 2.2 × 105 A/W at 1550 nm; the external quantum efficiency (EQE) of 1.76 × 107%; a high photocurrent polarization ratio of 0.686 and a polarization efficiency of 3.9 dB/mm at C-band. The integration of 2D materials on SPF paves the way to enhance the light–2D material interaction and achieve high performance multifunction-in-one fiber-integrated optoelectronic devices.

The well-known magnetoelectric dipole (ME-dipole) has huge adoption in antenna designs. In this paper, we manage to implement ME-dipoles in metasurfaces. The unit cell of an ME-dipole metasurface consists of a cross slot etched on the middle metal layer and an ME-dipole loaded on each side of the middle metal layer. The unit cell of an ME-dipole metasurface is designed based on the antenna theory, i.e., one ME-dipole works as a receiving antenna while the other ME-dipole works as a transmitting antenna. The metasurface is then formed by arraying these unit cells in a periodic grid with optimal cell size. Three ME-dipole metasurfaces, including a frequency selective surface (FSS), a polarizer, and a transmitarray, are presented to show the potential of the proposed metasurface design method. The proposed concept and the design method are validated using simulation as well as experiments.

In this article, a new tunable absorber and polarizer using one-dimensional anisotropic graphene photonic crystal (1D AGPC) is proposed for terahertz applications. The optical properties of the 1D AGPC structure is obtained through the transfer matrix method (TMM) calculations. In our design, a single defect layer is introduced in the 1D AGPC structure to increase its absorption. The absorption coefficient is further modified by optimizing the AGPC parameters such as the number of photonic crystal periods, the defect layer thickness, and the chemical potential of graphene. The modified structure can provide perfect absorption with a narrow bandwidth of 0.05 THz. On the other hand, considering the anisotropic optical properties of graphene, polarization dependence of the absorption coefficient is investigated. This feature of the structure can be employed to realize a tunable terahertz polarizer by adjusting incident angle at θ0 = 80°. In this way, high tunable polarization extinction ratio of 6.1 dB to 11.63 dB with respectively very narrow bandwidth of 0.031 THz to 0.023 THz are obtained. The maximum insertion losses within the tunable frequency range are as low as 0.023 dB and 0.031 dB. Hence, our design may have potential applications in narrow-band optoelectronic devices at the terahertz frequency range.

In this article, we optimized the preparation process of Hard Coat (HC) materials, studied the influence of UV and postbake parameters on curing rate and film surface warpage, improved the warpage of the film during the curing process, and successfully prepared a high‐hardness HC film that can be applied to touch display. At the same time, by optimizing the pretreatment of the film surface, the adhesion of the Anti‐Fingerprint (AF)material on the HC surface is improved, so that the surface of HC film has no scratches after abrasion test, and the WCA is kept above 110°, which meets requirement the of touch display. [ABSTRACT FROM AUTHOR]

This article presents a dual-circularly polarized array antenna based on gap waveguide technology operating at E-band. Double-grooved circular waveguide polarizers that utilize two annulus grooves placed at 45° and 135° offset from both excitation ports are used in this work. The operating principles of the polarizer are analyzed. Multilayer design using gap waveguide is implemented on the basis of the polarizer. The antenna consists of six layers, including three layers for the feeding networks, one layer for the polarizer, one layer of back cavity, and another layer of radiating grid. A 2 $\times $ 2 unit cell is proposed first and employed to realize an 8 $\times $ 8 planar array. Corporate feeding networks that use compact E-plane T-junctions and H-plane T-junctions are proposed. The antenna has been fabricated and verified by measurements. The measured results of S-parameters agree well with the simulation and show that reflection coefficients are better than −10 dB for both circular polarizations (CPs) from 76 to 81 GHz. The measured isolation between the input ports is larger than 25 dB in the operating band. The far-field measurements show that the antenna has realized gain larger than 24 dBi and axial ratios less than 1.5 dB from 76 to 81 GHz at boresight direction. [ABSTRACT FROM AUTHOR]

An integrated TM-pass/TE-stop polarizer centered at 850 nm is designed in this paper. The proposed polarizer is designed on a Si3N4 on insulator platform with tilted subwavelength gratings (SWG). Since the tilted SWGs have much more of an impact on the effective index of the TE polarization state than that of the TM polarization state, they help to achieve high TM and low TE transmission simultaneously. After geometries optimization, the polarizer's working bandwidth, which is defined as the wavelength region with an extinction ratio higher than 20 dB, is determined to be 185 nm under a SWG tilting angle of 30 degrees. At the same time, the insertion loss is always less than 0.45 dB over the entire working wavelength band. Finally, the results of fabrication tolerance analysis show that the SWG ridge width jitter only degrades the polarizer's working bandwidth by 16 nm. [ABSTRACT FROM AUTHOR]

Modern wireless networks, stationary terrestrial and satellite systems use many modern technologies to increase communication channels information capacity. They save limited frequency resources. In satellite communications the polarization signal processing is applied to reuse the allocated frequency bands. Usage of circularly polarized electromagnetic waves, which transmit useful signals, reduces fading effects and eliminates disadvantages introduced by multipath propagation interferences. In this case the distortion levels for signals with an odd number of electromagnetic waves reflections in the receiving antenna systems will be reduced down to the thresholds of their cross-polarization isolation. Besides, in the case of orthogonal polarizations usage, the achieved information capacity of the applied wireless communication channel multiples almost by the factor of two. The type of polarization of the used electromagnetic wave strongly determinates the peculiarities of the process of its propagation in the space or transmission line. Polarization signal processing is frequently carried out in horn feed systems of the reflector antennas. Such feed networks and systems allow to transmit and receive signals with several kinds of polarization at the same time. The fundamental element of dual circular polarization antenna feed networks is a waveguide polarization duplexer. The phase, isolation and matching characteristics of a polarization converter strongly influence on the functionality and polarization discrimination possibilities of the entire reflector antenna system. Therefore, the development and optimization of the characteristics of waveguide polarizers for satellite communication antennas is a crucial technical problem, which must be solved by fast and accurate methods. The comparison of electromagnetic performance of waveguide polarizers with sizes obtained using a fast single-mode technique and by more accurate trust region optimization method is carried out in this research. The results for differential phase shift, level of voltage standing wave ratio, ellipticity coefficient and cross-polarization discrimination are shown and discussed.

In AMOLED modules, the circular polarizer will shrink and generate stress in high temperature and humidity environment, leading to bending and deformation of the entire module. This paper explores the influence of different OCA storage modulus and distributions on the warpage of AMOLED modules by simulation. [ABSTRACT FROM AUTHOR]

We propose a carrier-depletion type Si optical modulator for transverse electric (TE) polarization loaded with an integrated polarizer. The integrated TE-pass polarizer with a bent waveguide has a compact and simple structure and demonstrate a polarization extinction ratio of 41.3 dB and insertion loss of 0.67 dB. This Si optical modulator loaded with the integrated polarizer achieved a maximum extinction ratio of 54.5 dB. It is expected to have a wide range of applications in digital coherent optical communication and optical sensing fields. [ABSTRACT FROM AUTHOR]

In this paper, an ultra-wideband (UWB) polarizer with high performance based on the metasurface is designed and demonstrated, which is composed of a dielectric substrate with a double-gap circular pattern and metal film. Multiple strong resonance points enable the design to achieve the conversion from incident linearly polarized waves to cross-polarized waves at 6.49–11.64 GHz, with a fractional bandwidth of 56.8% and a corresponding polarization conversion rate (PCR) of 90%. The PCR remains above 90% at 6.49–11.52 GHz when the electromagnetic wave is obliquely incident between 0° and 30°. Furthermore, the surface current distribution of the polarizer is discussed to explain the physical mechanism. The sample is fabricated for microwave validation. Compared with previous reports, the proposed polarizer has a larger bandwidth and higher efficiency and is expected to be used in microwave communications, antennas, radar cross section reduction, and other fields. [ABSTRACT FROM AUTHOR]

Objective: Dose distribution measurements of high‐energy X‐rays from medical linear accelerators (LINAC) in water are important for quality control (QC) of the system. Although Cherenkov‐light imaging is a useful method for measuring the high‐energy X‐ray dose distribution, depth profiles have an underestimated dose at increased depths due to the angular dependency of the Cherenkov light generated in water. In this study, we use a linear polarizer to separate the majority of polarized components from the majority of unpolarized components of Cherenkov‐light images in water and then use this information to correct for angular dependencies. Methods: A water phantom, a cooled charge‐coupled device (CCD) camera, and a polarizer were installed in a black box. Then, the water phantom was irradiated from the upper side with 6 or 10 MV X‐rays, and the Cherenkov light generated in water was imaged with the polarizer axis at both parallel and perpendicular orientations to the beam. By using these images from the two orientations relative to the beam, we corrected the angular dependency of the Cherenkov light. Results: By subtracting the images measured with the polarizer perpendicular to the beams from the images measured with the polarizer parallel to the beams, we could obtain images with only the polarized components. Using these images, we could calculate the images with non‐polarized components that had similar depth profiles to those calculated with a planning system. The average difference between corrected depth profiles and those calculated with the planning system was less than 1%, while that between uncorrected depth profiles and the planning system was more than 8.3% in depths of water from 20 to 100 mm. Conclusion: We conclude that the use of the polarizer has the potential to improve the accuracy of dose distribution in Cherenkov‐light imaging of water using high‐energy X‐rays. [ABSTRACT FROM AUTHOR]

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The organic light‐emitting diode (OLED) panels showed a significant color change in the solar radiation evaluation. After exposure to solar radiation, the luminance of some OLEDs was significantly decreased. In these OLEDs, the purity of electron transport layer (ETL) material was noticeably decreased after light exposure. It was determined that some gasses came out from the pixel‐define layer (PDL) by measuring the thermal desorption spectroscopy (TDS). By these gasses, the degradation was accelerated in organic layers and cathode. When the solar radiation evaluation was done with putting the 420 nm cut‐off filter on the panel, the color variation was absolutely disappeared. We paid attention to this result that the problem was solved by blocking a near‐UV light. A new capping layer (CPL) material increasing the absorption of near‐UV light was used. While the solar radiation evaluation was passed, they had very small process margin on evaporation of red and green interlayer. Moreover, color difference of white light was increased. When a near‐UV light absorbing dye was inserted to the polarizer film, color change in the solar radiation evaluation absolutely disappeared. Finally, we could pass the solar radiation evaluation through this attempt and the OLED panels with this polarizer film applied to mass production. [ABSTRACT FROM AUTHOR]

We have successfully developed a novel near‐infrared (NIR) polarizer fabricated from dichroic dyes. Unlike conventional wire‐grid polarizers, it exhibits transparency in the visible region and polarization wavelength tunability. Improvement of iris pattern recognition by eliminating the reflected light from the cornea surface has been demonstrated. [ABSTRACT FROM AUTHOR]

In this paper, a multistage Bragg grating with various kinds of periods is introduced in the design of a reflection-based TM-pass/TE-stop polarizer. The cascade grating sections reflect a wide wavelength range of the TE polarization state. Additionally, on the other hand, the TM polarization state always passes through the waveguide. Such a design facilitates the polarizer working bandwidth, which is defined as the wavelength range with an extinction ratio of greater than 20 dB, and can reach 231 nm using only three grating sections. Meanwhile, the incision loss is always less than 0.42 dB over the working wavelength band. Furthermore, if a slightly higher loss is permitted, the polarizer working bandwidth can be extended to further than 310 nm using five grating sections. [ABSTRACT FROM AUTHOR]