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Optically transparent electromagnetic applications, such as EMC windows, require high optical transparency (OT) while maintaining good electrical performance which is difficult to achieve due to trade-off between them. This paper presents a feasibility study on transparent electrodes (TE) for transparent EMI shielding applications. The proposed TEs are metal mesh film and saltwater representing solid and liquid TEs, respectively. The electrical and optical characterizations of the TEs are experimentally investigated with good agreement to numerical simulation. The MMF shows an average OT of 68.4% and strong SE of 31.4 dB, whereas the saltwater has an excellent average OT of 91.8% which is significantly higher than the conventional TEs. Moreover, the SE of planar saltwater is maintained above 22 dB with only 3 mm of thickness at the C-band (salinity 200 ppt) and it can be significantly improved by an increase in the thickness of the planar saltwater. The results prove that the proposed TEs can be considered as potential candidates for transparent electromagnetic shielding applications for different purposes.

An electromagnetic pulse (EMP) with high energy can damage electronic equipment instantly within a wide range of thousands of kilometers. Generally, a metal plate placed inside a thick concrete wall is used against an EMP, but it is not suitable for an EMP shielding window, which requires not only strong shielding effectiveness (SE) but also optical transparency (OT). In this paper, we propose a very thin and optically transparent structure with excellent SE for EMP shielding window application. The proposed structure consists of a saltwater layer held between two glass substrates and two metal mesh layers on the outside of the glass, with a total thickness of less than 1.5 cm. The SE and OT of the structure are above 80 dB and 45%, respectively, which not only meet the requirement of EMP shielding for military purposes but also retain the procedure of good observation. Moreover, the OT of the structure can be significantly improved using only one metal mesh film (MMF) layer, while the SE is still maintained high to satisfy the required SE for home applicants. With the major advantages of low cost, optical transparency, strong SE, and flexible performance, the proposed structure can be considered a good solution for transparent EMP shielding windows.

Nature-inspired structures as transparent conducting electrodes are exciting alternatives to conventional TCEs because they provide higher transmittance and conductivity at low temperatures on flexible substrates. The current work is focussed to develop a metal mesh structure with the help of plant leaf vein as a template. Bilayer metal mesh of thickness 85%) and electrical resistivity of the order of 10−4 Ω cm. The metal mesh TCE based on leaf vein template opens up new ways of obtaining large charge transfer resolving the junction resistance problem encountered in case of metal nanowires.

본 논문은 향후 투명 디스플레이, 스마트글래스(smart glass) 등의 그 활용도가 증가 추세에 있는 투명전극과 관련된 논문이며, 본 논문에서는 투명 안테나 등의 투명 고주파 수동소자 설계 시, 투명 디스플레이 등에 가장 많이 사용되고 있는 ITO(Indium-Tin-Oxide)을 이용한 박막형(thin film type) 투명전극의 낮은 전기...

This chapter summarizes the applications of EMTEs in flexible bifacial DSSCs and FTTHs. A highly efficient nanostructured flexile transparent CE fabricated by a facile and low-cost method for DSSC devices is reported. This hybrid CE consists of a nickel micro-EMTE with in situ decorated PtNPs and fully embedded in a flexible transparent substrate, and demonstrates superior optoelectronic performances and excellent mechanical flexibility under bending stress. The in situ loading of PtNPs avoids the wastage of expensive platinum material, minimizes loss in optical transparency and facilities the high electro-catalytic activity for triiodide reduction. The synergetic features of the proposed hybrid PtNP-EMTE used as CEs for flexible DSSCs enable improved power conversion efficiency. When a Ti-foil is used as the photo-anode, unifacial flexible DSSCs with PtNP-EMTE CE exhibits an excellent PCE of 6.91%. In flexible bifacial DSSCs using PtNP-coated ITO-PEN as photo-anode and the PtNP-EMTE as CE, remarkable PCEs of 5.67% (front-side illumination) and 4.87% (rear side illumination) are recorded. The front-to-rear PCE ratio of our bifacial DSSC approaches 85%, which is among the highest in published literature. These promising results show the great potential of this hybrid transparent CE in scalable production and commercialization of low-cost and efficient flexible DSSCs. Based on LEIT fabricated micro-EMTEs, a transparent and flexible thin-film heater is also fabricated, demonstrating excellent performance compared with existing products. With superior performances, our micro-EMTEs and nano-EMTEs are potential candidates for other flexible electronic devices as well.

This chapter presents the LEIT fabrication for micro-EMTEs in detail. The LEIT fabrication approach replaces vacuum-based metal deposition with an electrodeposition and is potentially suitable for high-throughput, large-volume and low-cost production. This approach can be easily adapted to make flexible and even stretchable devices Jang et al. (IEEE transaction on Antenna and Propagation, 2015 [1]). Prototype copper micro-EMTEs are fabricated on flexible COC films with superior electrical conductivity and optical transmittance. FoM (σdc/σopt) values as high as 1.5 × 104 have been demonstrated on the sample copper micro-EMTEs. This fabrication process has been demonstrated to be able to scale for a larger EMTE area and a wide range of materials. Because of the electrode’s embedded nature, excellent mechanical, chemical, and environmental stability were observed

Indium thin oxide (ITO)-free planar perovskite solar cells (PSCs) were fabricated at a low temperature (150 &deg, C) in this work based on the transparent electrode of photolithography processed nickel/gold (Ni/Au) mesh and the high conductivity polymer, PH1000. Ultrathin Au was introduced to increase the conductivity of metal mesh, and the optimal hexagonal Ni (30 nm)/Au (10 nm) mesh (line width of 5 &mu, m) shows a transmittance close to 80% in the visible light region and a sheet resistance lower than 16.9 &Omega, /sq. The conductive polymer PH1000 not only smooths the raised surface of the metal mesh but also enhances the charge collection ability of metal mesh. The fabricated PSCs have the typical planar structure (glass/Ni-Au mesh/PH1000/PEDOT:PSS/MAyFA1&minus, yPbIxCl3&minus, x/PCBM/BCP/Ag) and the champion PSC (0.09 cm2) obtains a power conversion efficiency (PCE) of 13.88%, negligible current hysteresis, steady current density and PCE outputs, and good process repeatability. Its photovoltaic performance and stability are comparable to the reference PSC based on the ITO electrodes (PCE = 15.70%), which demonstrates that the Ni/Au mesh transparent electrodes are a promising ITO alternative to fabricate efficient PSCs. The relatively lower performance of Ni/Au based PSC results from the relatively slower charge extraction and stronger charge recombination than the ITO based PSC. Further, we tried to fabricate the large area (1 cm2) device and achieve a PCE over 6% with negligible hysteresis and steady current density and PCE outputs. The improvements of perovskite film quality and interface modification should be an effective approach to further enhance the device performance of Ni/Au based PSCs, and the Ni/Au mesh electrode may find wider applications in PSCs and flexible devices.

The electrochemical part of the transfer function of an electrochemical transducer is studied. The transduction processes are simulated, the processing of the mechanical signal in time is shown, and the electrochemical part of the transfer function of the electrochemical transducer with mesh electrodes is calculated. We also measured directly the electrochemical part of the transfer function of an electrochemical transducer with mesh electrodes by direct control of the mechanical flow of electrolyte in the channel of the transducer. A good agreement of the calculations with the experiment was found. The method of a priori estimation of the electrochemical efficiency of a transducing element, irrespective of which hydromechanical oscillatory system it is built in, is extremely important for the development of microelectronic electrochemical devices.

A metal mesh device has a structure in which through-holes of the same shape are periodically placed on a thin metal film, and the selection of such a structure makes it possible to sense objects of various sizes. In this study, we showed the structure of the metal mesh device and the relationship between the detectable optical domain and the size of the objects to be measured. In addition, from measurement of changes in electromagnetic wave transmission characteristics of the metal mesh device due to specific adsorption of particles with a mean diameter of 100 nm with surface modification with Streptavidin to a metal mesh device fixed with biotin, we showed that even large particles can be sensed. Based on these examinations, we showed that, by using a metal mesh device with detectable optical domain corresponding to the size of objects, even objects that are larger than protein can be sensed.

A foldable organic light-emitting diode display integrating a touch sensor is fabricated. The touch sensor has an in-cell structure where metal-mesh sensor electrodes are formed in a counter substrate. It is demonstrated that touch on the entire panel surface, including a bent portion, is detected and that the touch panel operates correctly after 100,000 folding operations with a radius of curvature of 5 mm.

An 8.67-inch foldable OLED display with an in-cell touch sensor, in which metal-mesh sensor electrodes are formed in a counter substrate of the display, is fabricated. The OLED display demonstrates normal operation after 105 folding operation with 5 mm as the radius of curvature.

Imbalanced water management in a proton exchange membrane (PEM) fuel cell significantly reduces the cell performance and durability. Visualization of water distribution and transport can provide greater comprehension toward optimization of the PEM fuel cell. In this work, we are interested in water flooding issues that occurred in flow channels on cathode side of the PEM fuel cell. The sample cell was fabricated with addition of a transparent acrylic window allowing light access and observed the process of flooding formation (in situ) via a CCD camera. We then explore potential use of terahertz (THz) imaging, consisting of femtoelectron-based THz source and off-angle reflective-mode imaging, to identify water presence in the sample cell. We present simulations of two hydration states (water and nonwater area), which are in agreement with the THz image results. A line-scan plot is utilized for quantitative analysis and for defining spatial resolution of the image. Implementing metal mesh filtering can improve spatial resolution of our THz imaging system.

We present a new touch panel structure using a metal mesh and Ag nanowire film on one side of the base material. It is confirmed that the fabricated touch panel has low electrical resistance and equivalent touch sensitivity compared to a conventional touch panel using ITO or Ag nanowire.

An Al-N system optical absorption layer has been developed, to be used for Al-based metal mesh electrodes on touch screen panels. The triple-layered electrode effectively suppresses the optical reflection in both visible light and the blue color region and exhibits excellent wet etching property that accommodates micro-fabrication. Due to its high noise immunity and contact sensitivity originating from its low electrical resistivity, the proposed metal mesh electrodes are useful for touch-sensitive panels in the next generation ultra-high-resolution displays. key words: touch screen panel, metal mesh electrode, projected capacitive, invisible, etching property

We have newly developed the mutual-capacitive touch screen using double layered metal mesh electrodes with separated floating electrodes in borders between X- and Y-directional electrodes. We have defined the effect of the floating electrode with an electric field simulation and improved the sensitivity and the response time of the touch screen by separating the floating electrode into several small patterns.

A hybrid printing technique has been developed to manufacture high resolution metal mesh as flexible transparent conductors. The metal mesh structures are made by embedding silver nanoparticles inks into trenches which are patterned by high resolution nanoimprinting technology. Compared to other nanosilver type or metal mesh type of transparent conductors, the new technology can make much finer metal mesh ( 88%). The transparent conductor sheets can be roll-to-roll printed, which offers significant cost advantage over ITO electrodes. The new technology has been successfully implemented in high volume manufacturing of touch panel sensors for displays, as well as adapted to making flexible OLED.

We have developed a new high performance projected capacitive touch screen which has double layered metal mesh electrodes. By using high conductive metal electrodes and optimizing the mesh design, high sensitive 15-inch diagonal self capacitance touch screen and 8-inch diagonal mutual capacitance touch screen, both of which are optically bonded to LCD modules, have been developed.

Separating and detecting specific polarisations at multiple frequencies can be required for a number of scientific cases. However, in some cases, constraints on polarisation are defined by the choice of detectors used. In this paper we will present two devices that have been designed and built to increase performance when designing an optical system with these constrains. They are a polarisation sensitive dichroic plate and a linear polarisation rotator. Both are broadband and low loss and can be scaled to work from 20 GHz to 10 THz.

Terahertz frequencies experiments has motivated the development of new sources, detectors and optical components. Here we will present a review of THz bandpass filters ranging from 0.4 to 10 THz. We also demonstrate our fabrication process, simulations and experimental results.

Transparent conductive oxide (TCO) is an important part in the construction of dye-sensitized solar cells (DSCs) because of its low sheet resistance, sufficient light transparent ability and high photoelectrical response as a porous photo-electrode material of DSCs. However, the use of TCO for the two DSC electrodes can result in significant cost increase for the less effective DSCs compared to Si based solar cell. Therefore, the replacement of TCO is required for the commercial production of DSCs. In this study, TCO electrodes are replaced by stainless steel mesh. The 3.44[%] efficiency of the prepared TCO-less DSCs sample was obtained.

We report on a recently developed superior ITO-alternative transparent conductor, based on metal mesh technology. Trademarked by Rolith, Inc as NanoWeb®, metal mesh has the narrowest lines on the market (< 1 micron), which assures complete invisibility of the mesh under the most strict illumination conditions. It has also removed the necessity to optimize metal mesh design for each display structure, since it does not create a visible Moire fringes, as do other metal mesh conductors on the market. We report also on “best-in-class” optical, electrical and mechanical performance of NanoWeb conductor fabricated on glass plates and PET films.

Touch screen panel is one of the most innovative parts in modern electronic devices. We developed a single-layer printed metal-mesh touch screen sensor using projective capacitive touch sensing. The sensing electrodes and routing electrodes are printed at once forming a single layer by reverse-offset printing using Ag nanoparticle ink. Each sensing electrode is composed of rectangular metal mesh. In this paper, we described the manufacturing process of 5“ single-layer printed metal-mesh touch sensor implemented on transparent plastic film.

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.

© 2014 IEEE.This paper shows simulated and measured results of ultra-low cost metal mesh filters on electrically thick substrates for millimeter-wave and THz bands. It provides a broad overview of metal mesh filters currently available and suggest why it is worth moving to an electrically thick substrate for ultra-low cost applications. We demonstrate scalable traditional metal mesh filters on 525 μm thick fused silica substrates. In addition, trapped-mode excitation is exploited to improve out-of-band rejection at higher frequencies. The measured results prove that these filters are scalable in the THz range using cost-effective micromachining manufacturing. This work opens up the possibility of using electrically thick metal mesh filters for ultra-low cost applications.

Metal mesh sensors that work at higher frequencies were developed and tested. The experimental results indicated that the sensitivity at 10 THz was 50 times that at 1 THz. The high sensitivity was attributed to the localized electromagnetic field and the optical thickness of the sample.

We have recently designed, built and measured an alternative solution to the use of classical dielectric material in anti-reflection coatings. A metal-mesh pattern has been designed to cover a frequency band greater than 90%. We discuss measurements and illustrate the extension for bi-refringent materials.

We report on the fabrication and optical properties of thin metal films periodically patterned with square hole arrays of 2 micron pitch, which behave as substrateless plasmonic devices at mid-infrared frequencies. Large (3×3 mm2) meshes were fabricated by metallizing a patterned silicon nitride membrane. The mid-infrared spectra display resonant absorption lines with a Q-factor up to 22 in both transmission and reflection, due to the interaction of the radiation with surface plasmon modes on both faces of the film, allowed by substrate removal. The devices can be used to fabricate surface plasmon-based chemical sensors employing mid-infrared radiation.

We review our recent results on development of passive quasi-optical selective devices based on single- and multilayer metal mesh structures with subwavelength topology of mesh cells designed for filtering radiation at frequencies from a few tens GHz up to ten THz: frequency filters, polarizers, metastructures.

We have been developing novel widely tunable terahertz wave sources using nonlinear optical effects, and we have suggested a whole range of real-life applications using terahertz CT, metal mesh sensor, and time of flight tomography.

In this report we discuss main types of metal mesh based selective components of THz-quasi-optics required for applications in experiments at Novosibirsk terahertz free electron laser. The first experimental results on development of thin-film metal mesh polarizers and frequency filters by photolithographic and electroforming techniques are presented.

Thermophotovoltaic power conversion offers efficiencies (∼13%) higher than the currently used Si/Ge thermoelectric generators (∼6%) for Radioisotope powered space vehicles. Low bandgap GaSb TPV cells exhibit good spectral response in the 1 to 2 micron range and are hence well suited for such applications. In this work, we report on a novel idea to further enhance TPV system efficiencies by integrating the GaSb PV cell front metal contact with the TPV spectral control component, a band‐pass filter. A GaSb TPV Cell with integrated band‐pass filter contact was fabricated and its electrical and optical characteristics measured.

A new metal mesh coupler that makes use of a tunneling effect of evanescent waves between a metal mesh and a dielectric plate, has been proposed as a quasi-optical component for millimeter and submillimeter wavelengths. Theoretical calculation and experimental measurement performed from 40 GHz to 60 GHz show that the transmittance of the coupler can be changed more than 50% for the variation of a spacing less than 0.18 mm between a capacitive mesh and a silicon plate at around 57 GHz. >

In conclusion we have shown a dielectric coated metal mesh that behave like a filter with the passband wavelength shift by n times its origin value and at the sametime increasing its aperture by n2. In addition, if we can chose a right dielectric material the application of mesh filter could extend considerably.

Metal mesh devices were developed with a greater sensitivity at 10 THz than at 1 THz. Detection of a biotin– streptavidin combination was tested using these devices operating at 40 THz to evaluate their high-sensitivity capability. Experimental results showed that the combination was clearly detected label-free by a red spectral shift, indicating the possibility of using these metal mesh devices for medical inspections.