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International audience; This paper concerns the protection of electro-optic and electromagnetic sensors embedded into a metallic cavity equipped with a window made of a non-electrically conducting material and optically transparent over the visible light and/or infra-red spectrum. In the presence of high intensity radiated fields, the cavity must be appropriately shielded to protect those sensors, this protection being detrimental to EM sensors sensitivity in their absence. We propose here an automatic and quasi-instantaneous activation of an electromagnetic shield printed on the window glass through the detection of the impinging electromagnetic field. The presented solution is based on thin micrometric mesh-metal film deposited on a glass substrate surrounded by a parallel arrangement of p-i-n diodes polarized by the EM field source itself. An experimental validation is performed using a reverberation chamber to generate the electromagnetic field stress while performing a shielding effectiveness measurement using the nested reverberation chamber test setup.

International audience; This study investigated the performance of a Mosaic Frequency Selective Surface (MFSS) structure for two different applications: optical transparency and absorber. The MFSS for optical transparency application is comprised of a polycarbonate substrate with permittivity, epsilon(r) of 2.9, and the MFSS for absorber application utilized a Polyethylene Terephthalate (PET) substrate with epsilon(r) of 2.7. The MFSS unit cell is composed of a conductive metallic element design that integrates the Koch fractal and the double hexagonal loop for the optical transparency application. Meanwhile, the resistive MFSS unit cell with sheet resistivity of 100 Omega/sq is utilized for the absorber application. A Computer Simulation Technology (CST) Microwave Studio software is employed to carry out the calculation and frequency response analysis for both applications. Based on the results, it was concluded that the transparent MFSS yielded a wideband stopband and passband responses (fractional bandwidth (FBW) > 50%) with a low cross-polarization (-37 dB), and a wideband absorptivity response was achieved with thin MFSS absorber. In addition, the simulated and measured responses of the transparent MFSS achieved well-fitted correlations. The findings indicated that the proposed MFSS unit cell able to provide wideband response for both applications.

In this article, an optically transparent antenna, integrated in organic light-emitting diodes (OLEDs), is proposed for sub-6 GHz 5G applications. The concept of the mesh geometry is applied to obtain high optical transparency. To validate this technique, the transparent antenna is compared with the non-transparent in terms of electrical, optical and radiation parameters. These antennas are designed on a transparent glass substrate with dimensions of 30 × 35 mm2 and using copper films. The two antennas cover the 3.5 GHz band for 5G applications. The peak gain of the transparent antenna integrated in OLEDs light sources is 5.53 dB at 3.57 GHz. The gain value, improved after the integration, can be justified by the effect of OLEDs layers.

Authors developed novel stretchable films based on epoxy resins, which showed excellent printability for various conductive or dielectric inks without any surface treatments, excellent optical transparency, and low retardations. This film is expected to be used as substrates for various printed electronics applications e.g. foldable displays or lighting devices, stretchable/wearable sensors, etc.

Authors developed novel plastic films based by epoxy resins, having very high durability against repeated folding, excellent printability for various conductive or dielectric inks without any surface treatments, excellent optical transparency and very low retardations. These films are especially recommendable as substrates to various printed electronics applications e.g. foldable displays and versatile printed electronics applications such as lighting devices, sensors, etc.

A low cost optically transparent and frequency-reconfigurable water antenna is proposed in this paper. The proposed water antenna is mainly made of plexiglass (er = 3.4) and seawater. Thus, the most distinctive feature of this water antenna is that its whole structure is almost completely optically transparent and its cost is very low. Another attractive feature of the proposed antenna is that it can achieve frequency reconfiguration. The water ground is divided into four sections, in which four work states are realized by injecting seawater into different section. Simulation results show that impedance bandwidth for| S11| < -10 dB under four different states is stable at about 22% and the tuning range is from 1.46GHz to 1.64GHz. Besides, radiation patterns and efficiency are able to maintain stability even if at different work states. Due to these features such as high optical transparency, low cost and excellent frequency reconfiguration, the proposed water antenna is very suitable for the integration of various solar cells and solar panel.

Transparent antennas and radio-frequency (RF) components have recently attracted much attention because they can be monolithically integrated with lighting and photodetection devices for creating compact and multi-functional modules. In this work, we theoretically studied and experimentally manufactured high-performance, large-area conductive nanocomposites, which provide the unprecedented optical transparency (~96%) and moderately high electric conductivity (~ 12.5 Ω/sq). We have experimentally demonstrated several transparent antennas working at different frequencies: a flexible printed dipole antenna (2.95 GHz), a high-gain Fabry-Perot (FP) cavity antenna based on the optically-transparent metasurface (8 GHz), and a multifunctional RF -solar energy harvesting platform (~2.4 GHz). Our high-performance transparent antennas may find a broad range of applications in future wearable electronics and internet-of-thing (IoT).

In this article the technique of non-invasive determination of a iron level in a blood and, therefore, hemoglobin is proposed. The system operates on the basis of changes in the optical transparency of tissue under the influence of an external magnetic field, based on the fact that the tissue is saturated with blood containing the iron. Since the change in transparency is extremely small, a number of measures have been taken to highlight the useful signal, namely, at first, a constant component determined by the average illumination of the receiver is excluded, and then the signal is detected through the implementation of synchronous detection, which allows recognizing the signal at a signal-to-noise ratio of −100 dB.

This paper proposes a novel concept of an optically invisible antenna-on-display (AoD) realized using photolithography that can be integrated in active display panels such as OLEDs and LCDs. The proposed approach is exemplified for future millimeter-wave 5G mobile devices. A multi-layer structure with AoD is proposed and designed for potential beam-steering applications. The designed and fabricated 1×8 AoD exhibits 9.16 dBi boresight gain at 28 GHz while maintaining 88% optical transparency.

Recently, oxide-based thin film transistors (TFTs) are considered as a potential alternative to Si -based TFTs in backplane technology for the active-matrix display application due to its good optical transparency and excellent uniformity over large area [1]–[2]. Among all the oxide semiconductors, TiO 2 , with its high transparency to visible light, low-cost growth method, as well as great chemical and mechanical stability, has attracted more attentions [2]–[4]. TiO 2 -based TFTs with appreciable performances have been reported in some previous works, demonstrating their potential in display applications [2]–[6]. Herein, we present high-performance TFTs based on 15 nm ultrathin body TiO 2 with record on/off current ratio of $4.87\times 10^{8}$ and average subthreshold swing (SS) of 129 mV/dec.

an optically transparent monopole antenna based on indium tin oxide (ITO) is investigated in this paper. The optically transparent ITO thin film is used as the conductive layer, which is coated on an optically transparent glass substrate. The proposed antenna not only owns the merit of ultra-wide bandwidth, but also possesses a high optical transparency and light weight, and it is expected to be easily integrated to the surface of windows, and applied in many ultra wideband applications, with little chance of detection.

The temporary assembly of Glass and polystyrene (PS) substrates, regarding organic-inorganic hybrid structures, enable new opportunities for realizing flexible devices based on thin-film transistors (TFTs). In this paper, we report a new method for bonding of glass and polystyrene substrates with vacuum ultraviolet-ozone (VUV/O3) surface treatment without employing heat as well as debonding with high-low temperature circle in the fabrication procedure of display process. The integrated area of bonding pairs were measured to be >75% after keeping in storage at room temperature (~25oC) about 24 h, which represents a superior strength. Moreover, with nearly no flaw bonding interface the polystyrene-glass bonding pair performs superb optical transparency. Detailed properties characterization of bonding interfaces and VUV/O3 treated surfaces were implemented and analyzed. In debonding part, with a view to the thermal expansion discrepancy between two substrates we successfully separate glass and polystyrene substrates after high-low thermal circle (100-0oC). This feasible technique to achieve effective bonding and debonding of glass and polystyrene substrates in fabrication process for display devices.

In this paper, metasurfaces with optical transparency is proposed to control either the propagation or the scattering of microwave. Specifically, we have designed a band-pass frequency selective surface (FSS) with a transmission window around 1.6 GHz and a coding metasurface for suppressing the backward scattering with broad working band from 7.8 to 15 GHz. The proposals provide new opportunities to tailor the microwave propagation and scattering with simultaneously high transmittance in visible frequencies, which could offer many benefits in practical uses, such as window and solar panel applications.

Inorganic glass is promising material for carrier substrate of fan-out WLP and PLP process due to its stiffness, optical transparency, heat resistance and flatness. In addition, adjustability and flexibility of coefficient of thermal expansion is exceptionally useful to suppress warpage after molding process. In this paper, technical features of glass will be described.

This paper presents an optically transparent wideband High Impedance Surface (HIS) at 5 GHz. The surface is designed on acrylic substrate. Results show a good matching between the proposed circuit model, EM simulations, and measurements. The ±90° BW is 1 GHz (from 4.5 to 5.5 GHz) and the optical transparency is 80%.

This paper present the design and performance results of transparent Butler Matrix (BM) using Micro-metal Mesh (MM) conductive film as a conducting element and a glass as a substrate. The transparent Micro-metal Mesh (MM) conductive film have a very remarkable properties. Not only high optical transparency, it also high in electrical conductivity. It has a sheet resistance of 0.7 Ω/sq and a visible-light transmission (VBLT) of 75% respectively. The transparent Butler Matrix (BM) operates at 2.45 GHz frequency. These type of Butler Matrix (BM) can be installed to the glass surface of the building for the future 5G wireless communication internally where beam forming is required.

We demonstrated a flexible and transparent benzene sensor using cobalt-metalloporphyrin (Co-MPP)-functionalized few-layer MoS 2 as sensing material for the first time. The sensor detected benzene down to 10 ppm at room temperature. The functionalization with Co-MPP catalysts enhanced sensitivity (ΔR/R 0 ) over 250% compared to pristine MoS 2 . The fabricated sensor showed good mechanical flexibility and optical transparency, which is advantageous for a wide variety of chemical sensing applications.

Device-wafer bonding provides a platform for the implementation of ultra-high-efficiency multijunction solar cell designs, by allowing optimal subcell bandgap combinations to be attained while using only high-quality materials lattice-matched to their growth substrates. One promising new method for achieving wafer bonding is to use carbon nanotube composite thin films as the bonding agent between subcells grown on dissimilar substrates. In this paper we present the first demonstration of CNT-composite bonding of III–V materials, and evaluate its suitability for solar-cell integration in terms of optical transparency, electrical conductivity, bond uniformity and robustness, and bonded-device electrical performance. Another, relatively more mature method for device-wafer integration is that of direct semiconductor bonding technology. In order to provide a basis for comparison with CNT-bonding, we also summarize the latest achievements of the SBT solar cell development effort at Spectrolab.

This paper outlines the market for transparent optical networks and how these have developed, from their simple origins of saving the costs of OEO regeneration in point-to-point WDM links, to today's ring and mesh networks with flexible/reconfigurable nodal traffic access, using multi-way ROADM's. The paper then reviews and compares the technology options for multi-way ROADM's and the impact that full optical transparency has on the overall network design. The paper also considers alternative approaches, using OEO conversion and electrical switching, and suggests where these or transparent optical switching may be most applicable in an increasingly cost-sensitive environment.

In this paper, we present optically transparent flexible conductive polymer antennas for radio frequency identification systems. The designs for these antennas are presented along with simulated and measured results of antenna radiating properties. These conductive polymer antennas are compared to antennas with the same design fabricated out of copper. Finally, we include an analysis of the optical transparency of the conductive polymer antennas.

Self-assembled porphyrin wires are fabricated using various nitroporphyrin molecular units. 5-nitro-10,15,20-triheptylporphyrin is found to give the greatest optical transparency and straights wires. A focused ion beam (FIB) is used to demonstrate milling and shaping of the wires.

We discuss the development of a monolithically integratable optical isolator. The device is a semiconductor optical amplifier with a magnetized ferromagnetic metal contact. 12.7 dB of isolation combined with optical transparency has been demonstrated.

In this paper the potential benefits and challenges for the introduction of optically transparent network elements in metro and backbone networks are discussed. The migration from current to next technology generation transport equipment is assessed.

Room temperature carrier lifetimes of both type-I and type-II InP-based multiple quantum wells near optical transparency were measured using the pump-probe technique. Longer carrier lifetime in the type-II sample was observed.

Today's optical networks usually still perform electrical signal processing at the nodes. However, optical switching is available which allows transparent data transmission along lightpaths. Additionally, hardware cost can be reduced by saving on transponders. We investigate different approaches for providing selective regeneration while considering the impact of physical transmission limitations. Mathematical programs are formulated to obtain optimal results.

We investigate WDM layer network cost in typical North American networks and show that optical transparency at degree 2 and system reach between 1000-2000 km is sufficient for traffic loads between 1 -13 Tb/s.

Summary form only given, as follows. In this study, we examined the potentiality of boron nitride (BN) thin films as a protective layer in PDPs. It has unique properties allowing the possibility of this application. We synthesized BN thin films by the ion plating method and investigated the properties of these films such as optical transparency, second electron emission and plasma-erosion resistance. The properties of these films were strongly influenced by the processing parameters in ion plating process.

The investigation carried out on the industrial crystals and analysis of the works of the different authors show that any choice of one or another method for the improvement of the qualities of the KH/sub 2/PO/sub 4/ (KDP) and KD/sub 2/PO/sub 4/ (DKDP) crystals depends on the specific application of the crystals and the types of defects in the crystals. The thermal conditioning can be effectively used for recovering optical transparency of gamma, X-ray, or UV irradiated crystals. The thermal and laser conditioning methods improving laser damage threshold are effective for the crystals used for the frequency, conversion of the high-intensive laser radiation. It is necessary to use the ionizing radiation conditioning method for the crystals worked.. at the ionizing irradiation conditions.

We have developed a method for fabricating almost any type of optical surfaces in diamond. The method consists of the following steps: First, a polymer film, spun onto diamond substrates of optical quality, is patterned by lithographic processes. Next, the surface relief is transferred into the underlying diamond by use of inductively coupled plasma dry etching in an oxygen/argon chemistry. Using this technique, we have successfully demonstrated the fabrication of diamond spherical microlenses, blazed gratings, Fresnel lenses, subwavelength gratings and diffractive fan-out elements. The spherical microlenses had apertures of 90 μm and f-number of 4. The phase error, measured with a Twyman-Green interferometer at 633 nm, was found to be less than 31 nm. The diffraction efficiency for the blazed grating was measured to be 68% at 400 nm, with a theoretical maximum of 71%. The subwavelength grating was designed for reducing surface reflections at a wavelength of 10.6 μm. Spectrophotometric results show that the optical transmission was increased from 70%, using a non-structured diamond substrate, to 97%, using our subwavelength structured diamond. Finally, the fan-out element has been tested with a 6 kW carbon-dioxide laser, to microstructure pieces of PMMA. The results are excellent, showing diffraction limited spots.

A phantom model of a human body made of polyacrylamide containing a nonionic surface-active agent, salt, sucrose, and alcohol has been developed to evaluate the local SAR distribution inside the biological body. The phantom is completely transparent before electromagnetic power is absorbed. It becomes white and opaque however by absorbing electromagnetic power so that it can be used to visualize the three-dimensional distribution of the absorbed electromagnetic power. By making use of this clouding phenomenon caused by the temperature increase, we can visualize or measure the electromagnetic power in three-dimensional ways in terms of SAR. The soft phantom models have been developed so far. The purpose of the present study is to develop the stiff phantom that is used without being supported by a container. The phantom composition is given at several frequencies in this paper. Polyacrylamide gel is used in this study because of its good optical transparency before clouding.

The concept of optical transparency in fibre networks and its positive and also negative impact on data transmission is reviewed and discussed. ITU-T Study Group 15 standardisation effort on optical transparency is reported.

Summary form only given. Here, we report on ferroelectric domain inversion in BaMgF/sub 4/ (BMF). This material has transparency to