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Showing papers on "Bend radius published in 2015"


Journal ArticleDOI
TL;DR: A smooth, ultra-flexible, and transparent electrode was developed from silver nanowires embedded in a colorless polyimide (cPI) by utilizing an inverted film-processing method, and the fabricated flexible devices showed only slight performance reductions of <3% even after repeated foldings with a 30 μm bending radius.
Abstract: A smooth, ultra-flexible, and transparent electrode was developed from silver nanowires (AgNWs) embedded in a colorless polyimide (cPI) by utilizing an inverted film-processing method. The resulting AgNW-cPI composite electrode had a transparency of >80%, a low sheet resistance of 8 Ω/□, and ultra-smooth surfaces comparable to glass. Leveraging the robust mechanical properties and flexibility of cPI, the thickness of the composite film was reduced to less than 10 μm, which is conducive to extreme flexibility. This film exhibited mechanical durability, for both outward and inward bending tests, up to a bending radius of 30 μm, while maintaining its electrical performance under cyclic bending (bending radius: 500 μm) for 100,000 iterations. Phosphorescent, blue organic light-emitting diodes (OLEDs) were fabricated using these composites as bottom electrodes (anodes). Hole-injection was poor, because AgNWs were largely buried beneath the composite's surface. Thus, we used a simple plasma treatment to remove the thin cPI layer overlaying the nanowires without introducing other conductive materials. As a result, we were able to finely control the flexible OLEDs' electroluminescent properties using the enlarged conductive pathways. The fabricated flexible devices showed only slight performance reductions of <3% even after repeated foldings with a 30 μm bending radius.

187 citations


Journal ArticleDOI
TL;DR: It is found that high-order OAM modes show preferable tolerance to the ring ellipticity and fiber bending, which can potentially enable Pbit/s total transmission capacity and hundreds bit/s/Hz spectral efficiency in a single TA-MOMRF.
Abstract: We present a compact (130 μm cladding diameter) trench-assisted multi-orbital-angular-momentum (OAM) multi-ring fiber with 19 rings each supporting 22 modes with 18 OAM ones. Using the high-contrast-index ring and trench designs, the trench-assisted multi-OAM multi-ring fiber (TA-MOMRF) features both low-level inter-mode crosstalk and inter-ring crosstalk within a wide wavelength range (1520 to 1630 nm), which can potentially enable Pbit/s total transmission capacity and hundreds bit/s/Hz spectral efficiency in a single TA-MOMRF. Moreover, the effective refractive index difference of even and odd fiber eigenmodes induced by the ellipticity of ring and fiber bending and their impacts on the purity of OAM mode and mode coupling/crosstalk are analyzed. It is found that high-order OAM modes show preferable tolerance to the ring ellipticity and fiber bending. The designed fiber offers favorable tolerance to both small ellipticity of ring (<−22 dB crosstalk under an ellipticity of 0.5%) and small bend radius (<−20 dB crosstalk under a bend radius of 2 cm).

123 citations


Journal ArticleDOI
TL;DR: A pose-sensing system for soft robot arms integrating a set of macrobend stretch sensors that is immune to electrical noise and magnetic fields, safe, and suitable for modular implementation in multi-link soft continuum robotic arms is introduced.
Abstract: This paper introduces a pose-sensing system for soft robot arms integrating a set of macrobend stretch sensors. The macrobend sensory design in this study consists of optical fibres and is based on the notion that bending an optical fibre modulates the intensity of the light transmitted through the fibre. This sensing method is capable of measuring bending, elongation and compression in soft continuum robots and is also applicable to wearable sensing technologies, e.g. pose sensing in the wrist joint of a human hand. In our arrangement, applied to a cylindrical soft robot arm, the optical fibres for macrobend sensing originate from the base, extend to the tip of the arm, and then loop back to the base. The connectors that link the fibres to the necessary opto-electronics are all placed at the base of the arm, resulting in a simplified overall design. The ability of this custom macrobend stretch sensor to flexibly adapt its configuration allows preserving the inherent softness and compliance of the robot which it is installed on. The macrobend sensing system is immune to electrical noise and magnetic fields, is safe (because no electricity is needed at the sensing site), and is suitable for modular implementation in multi-link soft continuum robotic arms. The measurable light outputs of the proposed stretch sensor vary due to bend-induced light attenuation (macrobend loss), which is a function of the fibre bend radius as well as the number of repeated turns. The experimental study conducted as part of this research revealed that the chosen bend radius has a far greater impact on the measured light intensity values than the number of turns (if greater than five). Taking into account that the bend radius is the only significantly influencing design parameter, the macrobend stretch sensors were developed to create a practical solution to the pose sensing in soft continuum robot arms. Henceforward, the proposed sensing design was benchmarked against an electromagnetic tracking system (NDI Aurora) for validation.

122 citations


Journal ArticleDOI
TL;DR: It is shown that re-arranging the nested anti-resonant tubes in the cladding to be adjacent has the effect of significantly reducing leakage as well as bending losses, and for reaching high loss extinction ratios between the fundamental mode and higher order modes.
Abstract: We report on numerical design optimization of hollow-core anti-resonant fibers with the aim of reducing transmission losses. We show that re-arranging the nested anti-resonant tubes in the cladding to be adjacent has the effect of significantly reducing leakage as well as bending losses, and for reaching high loss extinction ratios between the fundamental mode and higher order modes. We investigate two versions of the proposed design, one optimized for the mid-IR and another scaled down version for the near-IR and compare them in detail with previously proposed anti-resonant fiber designs including nested elements. Our proposed design is superior with respect to obtaining the lowest leakage losses and the bend losses are also much lower than for the previous designs. Leakage losses as low as 0.0015 dB/km and bending losses of 0.006 dB/km at 5 cm bending radius are predicted at the ytterbium lasing wavelength 1.06 µm. When optimizing the higher-order-mode extinction ratio, the low leakage loss is sacrificed to get an effective single-mode behavior of the fiber. We show that the higher-order-mode extinction ratio is more than 1500 in the range 1.0-1.1 µm around the ytterbium lasing wavelength, while in the mid-IR it can be over 100 around λ = 2.94 μm. This is higher than the previously considered structures in the literature using nested tubes.

90 citations


Patent
22 Jan 2015
TL;DR: In this article, a glass element having a thickness from 25 μm to 125 μm, a first primary surface, a second primary surface and a compressive stress region extending from the first primary to a first depth, the region defined by a compressed stress σI of at least about 100 MPa at the first surface.
Abstract: A glass element having a thickness from 25 μm to 125 μm, a first primary surface, a second primary surface, and a compressive stress region extending from the first primary surface to a first depth, the region defined by a compressive stress σI of at least about 100 MPa at the first primary surface. Further, the glass element has a stress profile such that it does not fail when it is subject to 200,000 cycles of bending to a target bend radius of from 1 mm to 20 mm, by the parallel plate method. Still further, the glass element has a puncture resistance of greater than about 1.5 kgf when the first primary surface of the glass element is loaded with a tungsten carbide ball having a diameter of 1.5 mm.

69 citations


Journal ArticleDOI
TL;DR: In this article, the fabrication and characterization of highly flexible indium-gallium-zincoxide (IGZO)-based thin-film transistors (TFTs) and integrated circuits on a transparent and thin polymer substrate is presented.
Abstract: In this paper, we present the fabrication and characterization of highly flexible indium-gallium–zinc-oxide (IGZO)-based thin-film transistors (TFTs) and integrated circuits on a transparent and thin polymer substrate. Mechanical reliability tests are performed under bending conditions down to a bending radius of 2 mm. All the TFT parameters show only a weak dependence on mechanical strain. TFTs can withstand bending strain up to 0.75% without any significant change in the device operation. Mechanical reliability is further demonstrated to a higher TFT integration level by ring oscillators and 8-b transponder chips operating at a bending radius of 2 mm.

60 citations


Journal ArticleDOI
TL;DR: The results indicate that the roles of the left and right steps may be functionally different during bend sprinting, and this specificity should be considered when designing training programmes.
Abstract: This study investigated changes in performance and technique that occur during maximal effort bend sprinting compared with straight-line sprinting under typical outdoor track conditions. Utilising a repeated measures design, three-dimensional video analysis was conducted on seven male sprinters in both conditions (bend radius: 37.72 m). Mean race velocity decreased from 9.86 to 9.39 m/s for the left step (p = 0.008) and from 9.80 to 9.33 m/s for the right step (p = 0.004) on the bend compared with the straight, a 4.7% decrease for both steps. This was mainly due to a 0.11 Hz (p = 0.022) decrease in step frequency for the left step and a 0.10 m (p = 0.005) reduction in race step length for the right step. The left hip was 4.0° (p = 0.049) more adducted at touchdown on the bend than the straight. Furthermore, the bend elicited significant differences between left and right steps in a number of variables including ground contact time, touchdown distance and hip flexion/extension and abduction/adduction angles. The results indicate that the roles of the left and right steps may be functionally different during bend sprinting. This specificity should be considered when designing training programmes.

46 citations


Journal ArticleDOI
TL;DR: Broadband, efficient, all-dielectric metamaterial-waveguide bends that redirect light by 180 deg.
Abstract: We designed, fabricated, and characterized broadband, efficient, all-dielectric metamaterial-waveguide bends (MWBs) that redirect light by 180 deg. The footprint of each MWB is 3 μm×3 μm and redirection is achieved for single-mode waveguides spaced by 1.3 μm, which corresponds to an effective bend radius of 0.65 μm ( 80% and ∼70%, respectively. Furthermore, the MWBs have an operating bandwidth >66 nm (design) and >56 nm (experiments). Our design methodology that incorporates fabrication constraints enables highly robust devices. The methodology can be extended to the general routing of light in tight spaces for large-scale photonic integration.

38 citations


Journal ArticleDOI
TL;DR: In this article, both CNT-based flexible cathode and anode were fabricated by first attaching the vacuum filtered CNT film/mixed cellulose eater (MCE) filter membrane to an adhesive semi-cured poly(dimethyl siloxane) substrate, and then peeling off the MCE filter membrane.
Abstract: Utilizing carbon nanotubes (CNTs) as substitutes for the conventional rigid indium–tin oxide (ITO) electrodes, all CNT based flexible field emission devices (FEDs) were possible to prepare with a novel film transfer method. In the method, both CNT-based flexible cathode and anode were fabricated by first attaching the vacuum filtered CNT film/mixed cellulose eater (MCE) filter membrane to an adhesive semi-cured poly(dimethyl siloxane) substrate, and then peeling off the MCE filter membrane. Effects of bending direction and bending radius on field emission properties were studied. The field emission performance of the convex bending device was worse than that of the flat device and deteriorated further with the decrease of bending radius. In contrast, the concave bending device exhibited better field emission properties than the flat device; nevertheless, its field emission properties decreased as the concave bending radius reduced below a certain value. The method achieved two successes. One is that the interfacial interaction between CNT films and the flexible substrate was greatly enhanced. The other is that the transfer process improved the field emission properties due to the increase of vertically aligned CNT tips. Compared with traditional methods applied in FED preparation, the novel modified transfer method is organic free, easy to control, cheap, and environment friendly.

27 citations


Journal ArticleDOI
TL;DR: In this paper, a 60µm core diameter Yb free Er-La-Al doped single-trench fiber having a 0.038 ultra-low-NA, fabricated using conventional MCVD process in conjunction with solution doping technique.
Abstract: We demonstrate a 60µm core diameter Yb free Er-La-Al doped single-trench fiber having a 0.038 ultra-low-NA, fabricated using conventional MCVD process in conjunction with solution doping technique. Numerical simulations predict an effective single mode operation with effective area varying from 1,820µm2 to 1,960µm2 (taking bend-induced modal distortion into account) for different thicknesses of trenches and resonant rings at a constant bend radius of 25cm. Moreover, all solid structure favors easy cleaving and splicing. Experimental measurements demonstrate a robust effective single mode operation. Furthermore, with a 4%-4% laser cavity, this fiber shows a record efficiency of 46% with respect to the absorbed pump power.

20 citations


Journal ArticleDOI
01 Aug 2015-Urology
TL;DR: Performance characteristics of these new holmium:YAG optical fibers differed significantly but performance was on par or better than historical controls.

01 Jan 2015
TL;DR: In this article, the first pass of radial- rotary profiling of wheel crowns is used to determine the normal and shear stresses at bending radius of profiling roll while shaping and on stretching edge of die body while drawing.
Abstract: There considered questions concerning determination of stress field during form alteration of wheel crowns from steel cylindrical works at the first pass of radial- rotary profiling. There also fulfilled process analysis of drawing process of cylindrical pieces made of sheet metal. Determination of stresses at bending radius of profiling roll while shaping and on stretching edge of die body while drawing is of great interest, as coupling areas of various profile elements of crown are the most loaded and on the value of meridian stress depends the possibility of getting of high-quality piece per stretching pass. Results of theoretical research allow to analyze stresses, which arise while deforming, and determine group of technological and constructional parameters of profiling and stretching process, which affect greatly the value and distribution of normal and shear stresses.

Patent
03 Sep 2015
TL;DR: In this paper, the axially variable stiffening mechanism is adjustable between a first state in which an actuation of the control tendon produces a first bend radius in the steerable distal section and a second state that produces a second bend radius.
Abstract: A medical instrument comprises an elongate flexible body including a proximal section and a steerable distal section. The instrument also comprises a control tendon extending within the elongate flexible body. The instrument also comprises an axially variable stiffening mechanism including a first conduit extending through a second conduit. The axially variable stiffening mechanism is adjustable between a first state in which an actuation of the control tendon produces a first bend radius in the steerable distal section and a second state in which the actuation of the control tendon produces a second bend radius in the steerable distal section. The second bend radius is different than the first bend radius.

Patent
04 Nov 2015
TL;DR: In this article, a backplane of an electronic device assembly includes a glass composition substantially free of alkali ions, an elastic modulus of about 40 GPa to about 100 GPa, and a final thickness from about 20 μm to about100 μm.
Abstract: An electronic device assembly includes a backplane having a glass composition substantially free of alkali ions, an elastic modulus of about 40 GPa to about 100 GPa, and a final thickness from about 20 μm to about 100 μm. The primary surfaces of the backplane are characterized by a prior material removal to the final thickness from an initial thickness that is at least 20 μm greater than the final thickness. The assembly also includes a protect layer on the first primary surface of the backplane; and a plurality of electronic components on the second primary surface of the backplane. In addition, the backplane is configured with at least one static bend having a bend radius between about 25 mm and about 5 mm. The electronic components of the electronic device assembly can include at least one thin film transistor (TFT) element or organic light emitting diode (OLED) element.

Journal ArticleDOI
TL;DR: In this article, a mathematical model of equivalent bending radius was used to analyze the effect of bending strain on the critical current of yttrium barium copper oxide (YBCO) tapes in distorted bending mode.
Abstract: A mathematical model of equivalent bending radius was used to analyze the effect of bending strain on the critical current of yttrium barium copper oxide (YBCO) tapes in distorted bending mode. The relationship between critical current and twist pitch under different bending radii was measured. For enough larger twist pitch, even though the bending radius was smaller than the critical bending radius, the equivalent bending radius was always greater than the critical bending radius. Only when the bending radius was less than the critical bending radius and the twist pitch was reduced to a certain extent, the equivalent bending radius was smaller than the critical bending radius. As a consequence, the critical current dropped sharply and cannot be restored. The model and analytical equation was feasible and can be used for the design of solenoid YBCO magnet.

Journal ArticleDOI
TL;DR: In this paper, a model based on a back propagation neural network (BPNN) is introduced to reveal the relationship of bending radius with angle of die α, indentation s, pitch p, and width of strip w.
Abstract: Incremental in-plane bending (IIB) is a new and advanced flexible manufacturing technology for small-lot production of strip with various bending radii. The strip of sheet metal is bent incrementally by a beating inclined punch. The bending radius is strongly affected by mechanical properties of the material, geometry of the strip, and processing parameters. It is difficult to predict the bending radius due to the complex synergistic effects of the controlling parameters. How to predict the bending radius accurately has therefore become a key point to be urgently solved in the development of this advanced forming technology. In this paper, a model based on a back propagation neural network (BPNN) is introduced to reveal the relationship of bending radius with angle of die α, indentation s, pitch p, and width of strip w. Out of 14 different BPNN architectures trained, the 4-9-9-1 BPNN with two hidden layers having nine neurons trained with the Levenberg-Marquardt algorithm (trainlm) is found to be the optimum network model, and the prediction error is less than 2 % on average. Otherwise, a 1-9-9-4 reverse BPNN is developed to build the processing window for a given bending radius. Meanwhile, taking section moment of inertia I as a quantitative index of forming stability, α, p, s, w0 are optimized as design variables in order to make objective functions of I maximized simultaneously. Finally, to verify its predictive capability, the present approach is applied to a case study, and the optimal combination of parameters for stable forming during IIB is obtained.

Journal ArticleDOI
TL;DR: In this paper, an inner aluminum alloy thin-walled tube with a diameter-to-thickness ratio of 63 and relative bending radius of 2.2 was successfully formed under the internal pressure of 25 MPa.
Abstract: Bending of an aluminum alloy thin-walled tube with larger diameter-to-thickness ratio is more difficult than that of a mild steel or stainless steel tube due to its low elastic modulus and yield strength. To solve this problem, experiments were conducted on hydro-bending of bi-layered tubes, which consist of an outer mild steel tube and an inner aluminum alloy thin-walled tube. The wrinkling behavior, springback, cross-sectional non-circularity, and wall thickness variation of the inner aluminum alloy tube were analyzed. It has been shown that the internal pressure plays a prominent role in preventing the wrinkling due to an additional axial tensile stress being introduced to the inner tube through welding the inner tube ends onto the surface of the outer tube. By increasing the internal pressure to a critical value, it is helpful to reduce the magnitude of compressive stress at the inner side of bent tubes, so the onset of winking is prevented. The springback and the cross-sectional non-circularity become smaller, while the thinning rate gets bigger with pressure increasing. Finally, a sound aluminum alloy thin-walled tube with diameter-to-thickness ratio of 63 and relative bending radius of 2.2 was successfully formed under the internal pressure of 25 MPa.

Patent
04 Nov 2015
TL;DR: A bendable stack assembly that includes a glass element having a composition substantially free of alkali ions, an elastic modulus of about 40 GPa to about 100 GPa, and a final thickness from about 20 µm to approximately 100 µm, was presented in this paper.
Abstract: A bendable stack assembly that includes a glass element having a composition substantially free of alkali ions, an elastic modulus of about 40 GPa to about 100 GPa, a final thickness from about 20 µm to about 100 µm, a first primary surface substantially in tension upon a bending of the element, and a second primary surface substantially in compression upon the bending, the primary surfaces characterized by a prior material removal to the final thickness from an initial thickness that is at least 20 µm greater than the final thickness. The glass element also includes a protect layer on the first primary surface. In addition, the glass element is characterized by an absence of failure when the element is held during the bending at a bend radius of about 15 mm for at least 60 minutes at about 25C and about 50% relative humidity.

Journal ArticleDOI
Tao Chen1, Zhong Xie1, Zhihong Li1, Yanming Zhou1, Hai-Yan Guo 
TL;DR: In this article, a method of suppressing the oscillatory behavior of bending loss of polymer optical fibers (POFs) by partially removing the cladding and core was proposed, and the bending loss monotonicity with improved linearity was obtained for POFs with small bending radius in a large range of bending angles.
Abstract: Bending loss of polymer optical fibers (POFs) shows unexpected oscillatory behaviors due to the interference between whispering gallery mode and core mode for the cases of small bending radius and large bending angle. We have found a novel method of suppressing the oscillatory behavior of bending loss of POFs. By partially removing the cladding and core, the bending loss monotonicity with improved linearity was obtained for POFs with small bending radius in a large range of bending angles for the first time. This method is useful in the application of extreme large strain (e.g., ≥60%) sensors of POF.

Journal ArticleDOI
Jiang Sun1, Yanhui Qi1, Zexin Kang1, Lin Ma1, Shuisheng Jian1 
TL;DR: In this paper, a modified multitrench fiber (MTF) design with two gaps numerically through the scalar FD-BPM algorithm is proposed and investigated, and a large effective mode area (920μm2 ) is achievable with high loss ratio (>100.
Abstract: We propose and investigate a modified multitrench fiber (MTF) design with two gaps numerically through the scalar FD-BPM algorithm. Excellent potential in mode area scaling, suppression of high-order modes (HOMs), and resistance to bending is demonstrated. Loss ratio between HOMs and the fundamental mode is more than 50 possibly over a wide range of high-index-ring thickness, gap width, bending radius, and bending orientation. Therefore, the required fabrication accuracy decreases. At 1050-nm wavelength and 20-cm bend radius, large effective mode area (920 μm2 ) is achievable with high loss ratio (>100). The fabricating technologies, carving grooves in the ordinary MTF and inserting rods in these grooves, can be possibly used to fabricate our modified two-gap-MTF.

Patent
11 Aug 2015
TL;DR: In this article, a stack assembly is provided that includes a glass layer having a thickness, a first and second primary surfaces and a compressive stress region extending from the second primary surface to a first depth.
Abstract: A stack assembly is provided that includes a glass layer having a thickness, a first and second primary surface and a compressive stress region extending from the second primary surface to a first depth; and a second layer coupled to the second primary surface. The glass layer is characterized by: an absence of failure when the layer is held at a bend radius from about 3 to 20 mm, a puncture resistance of greater than about 1.5 kgf when the second primary surface is supported by (i) an ~25 µm thick PSA and (ii) an ~50 µm thick PET layer, and the first primary surface is loaded with a stainless steel pin having a flat bottom with a 200 µm diameter, a pencil hardness of at least 8H, and a neutral axis within the glass layer located between the second primary surface and half of the first thickness.

Journal ArticleDOI
TL;DR: In this paper, the authors introduced two important types of testing loads (i.e., entire reverse of bend and torsion with several cycles) to investigate the optical and flexible characteristics of film-type cholesteric liquid crystal displays (ChLCDs).
Abstract: Given that the induced stress resulting from fatigue bending or torsional loads increases with increasing display thickness, the long-term mechanical reliability of display modules in soft electronics has attracted considerable attention. Therefore, understanding the related failure mechanism and stress contour distribution in the display structure is important and necessary, particularly in torsional load application. This study introduces two important types of testing loads (i.e., entire reverse of bend and torsion with several cycles) to investigate the optical and flexible characteristics of film-type cholesteric liquid crystal displays (ChLCDs). The bending radius and the torsion angle used are 20 mm and ${\pm}{\hbox{10}}^{\circ}$ , respectively. The stress contour and possible failure location of the testing specimens are obtained by using non-linear finite element analysis (FEA). Results indicate that a significant optical characteristic decay occurs beyond 1000 testing times. In 11,000 cycles of fatigue bending and torsion tests, 45% and 55% decay change rates, respectively, are obtained for the National Television System Committee. Accordingly, a worse situation occurs at the torsion test. This phenomenon is attributed to a two-direction bend torsion exerted on the tested ChLCD. The foregoing behavior is validated by using FEA.

Patent
04 Feb 2015
TL;DR: In this paper, a portable cable bending radius acceptance checker is presented, which consists of two equally-long long rods, a short rod and an installation block, which can unfold by 90 degrees to the two sides respectively.
Abstract: The invention discloses a portable cable bending radius acceptance checker which comprises two equally-long long rods, a short rod and an installation block. One end of each of the two long rods is in damping hinge to the installation block; the two long rods can unfold by 90 degrees to the two sides respectively; the short rod is slidably connected to the installation block; the short rod is engraved with the lengths calculated through different cable standard bending radius standard values; the short rod is provided with a pin hole; by enabling a pin shaft to pass through the pin hole, the short rod can realize position fixation thereof on the installation block; and the free ends of the two long rods and the free end of the short rod are respectively provided with a rubber wire sleeve. The portable cable bending radius acceptance checker has the advantages of being low in cost, light and portable, and simple in operation identity and the like, and is a qualitative tool for cable bending radius acceptance.

Journal ArticleDOI
Haisu Li1, Guobin Ren1, Yixiao Gao1, Yudong Lian1, Min Cao1, Shuisheng Jian1 
TL;DR: In this paper, a single-mode trench-assisted bend-insensitive fibers (SM-TA-BIFs) based on the particle swarm optimization (PSO) was proposed.
Abstract: We present a novel design strategy of single-mode trench-assisted bend-insensitive fibers (SM-TA-BIFs) based on the particle swarm optimization (PSO). A performance index (PI) is defined as the ratio of bending loss to mode-field-diameter to evaluate the fiber performance comprehensively. For the PSO design of SM-TA-BIF, the fitness function is constructed by PI and Gauss weighting function, and cutoff wavelength is applied as the constraint condition. The minimum PI can be achieved by the Gauss weighting fitness function with a target bending radius. With the same trench parameters, but a trench located further away from the center, the average PI of the optimized SM-TA-BIF could be 3.2 times lower than that of a commercial BIF at a bending radius of 5 mm within the entire $C$ -band.

Patent
08 Oct 2015
TL;DR: A flexible display includes a plurality of pixel chips, chixels, provided on a flexible substrate as mentioned in this paper, and the chixels and the light emitters thereon may be shaped, sized and arranged to minimize chixel, pixel, and sub-pixel gaps and to provide a desired bend radius of the display.
Abstract: A flexible display includes a plurality of pixel chips, chixels, provided on a flexible substrate. The chixels and the light emitters thereon may be shaped, sized and arranged to minimize chixel, pixel, and sub-pixel gaps and to provide a desired bend radius of the display. The flexible substrate may include light manipulators, such as filters, light converters and the like to manipulate the light emitted from light emitters of the chixels. The light manipulators may be arranged to minimize chixel gaps between adjacent chixels.

Journal ArticleDOI
TL;DR: In this article, a novel design of porous octagonal photonic crystal fiber with a metal-coated central hole was investigated and analyzed in the terahertz (THz) range.
Abstract: In this study, a novel design of porous octagonal photonic crystal fibre with a metal-coated central hole is investigated and analysed in the terahertz (THz) range. The suggested structure is analysed near a frequency of 1.0 THz by using the full vectorial finite difference method. The effects of the structure geometrical parameters and bending radius on the mode effective index, effective mode area and attenuation of the proposed design are investigated. The numerical results reveal that the effective mode area with a metal-coated central hole is smaller than that of porous core without a metal-coated central hole by 80%. In addition, very low attenuation can be obtained because of the porosity inside the core region.

Proceedings ArticleDOI
06 Sep 2015
TL;DR: In this article, the authors demonstrate the feasibility of mechanically flexible and stretchable coplanar waveguide (CPW) transmission lines at millimeter-wave frequencies at 40 GHz.
Abstract: In this paper we demonstrate the feasibility of mechanically flexible and stretchable coplanar waveguide (CPW) transmission lines at millimeter-wave frequencies. Our approach is based on meander horseshoe-shaped CPW line on 125 µm-thick Polyethylene Naphthalate (PEN) dielectric substrate. The desired meander shape pattern of the conductor is structured using a nanosecond pulsed laser source operating at 351 nm wavelength by the precise patterning of a 1 µm-thick conductive film deposited on a plastic foil. The cutout is realized by following the outer meander shape path of the structure providing an ultra-flexible/stretchable interconnect line. An experimental attenuation below 0.12 dB·mm−1 for a 13 mm length of signal conductor has been obtained at 40 GHz. When submitted to bending on a semi-cylinder of known radius, the measured transmission coefficient show small variations less than 0.05 dB even for bending radius in the centimeter range.

Patent
29 Jul 2015
TL;DR: In this paper, a tape-winding type optical unit optical cable and a manufacturing process of the cable are described. But the manufacturing process is not described, except that the optical unit is covered by an aramid fiber at the center.
Abstract: The invention discloses a tape winding type optical unit optical cable and a manufacturing process thereof. The tape winding type optical unit optical cable comprises an optical unit and an outer sleeve layer, wherein the optical unit comprises a tape winding type optical fiber tape and an aramid fiber at the center, wherein a water-resisting material, a ribbon and a sleeve sequentially cover the tape winding type optical fiber tape. The manufacturing process comprises the following steps: 1, manufacturing a plurality of optical fibers into the optical fiber tape by a tape combining mold; 2, winding the optical fiber tape into a closed ring through a U-shaped molding trumpet mold and forming an optical fiber column by a sizing mold; covering the water-resisting material and binding the ribbon, and putting the optical fiber column into the sleeve to form the optical unit; and 3, preparing a tape winding type central pipe optical cable or a layer hinged type optical cable, and arranging a tape combining resin pressing-in pipe on the tape combining mold, wherein the optical fiber difference between the layers of the optical fiber column is 6, the outer diameter of the optical fiber column with 6-90 cores is 636-2332 microns and the layer quantity is 1-5, and the diameter of the prepared optical unit is 1.4-4.8mm. The sleeve has a smaller diameter and the prepared optical cable has light weight and small diameter; the bending radius of the prepared optical cable is small and the construction and pavement are easy; the net-shaped optical cable tape can be in primary fusion welding and the construction is convenient.

Patent
30 Jun 2015
TL;DR: In this article, the authors proposed a self-calibration function for measuring a radius of curvature for an underground wiring pipe having a self calibration function, which is capable of constructing more accurate data with respect to the underground wires pipe and further improving a construction quality of the underground wire pipe.
Abstract: The present invention relates to a system for measuring a radius of curvature for an underground wiring pipe having a self calibration function. The present invention comprises: a first pipe diameter measurement means measuring an inner diameter of an underground pipe; a second pipe diameter measurement means measuring the inner diameter of the underground pipe and having a length different from the length of the first pipe diameter measurement means; a communication means transmitting the measured diameter of the pipe to a central processing unit; and the central processing unit calculating the actual diameter (D) of the underground pipe and calculating a radius of curvature of the underground pipe. According to the present invention, the system is capable of constructing more accurate data with respect to the underground wiring pipe and further improving a construction quality of the underground wiring pipe.

Journal ArticleDOI
TL;DR: The response bandwidth and the group delay of direct modulated (IF) signal were independent of the channel waveguide for communication speeds up to more than 3 GHz and this technique is viable for low-cost, short-length buried optical waveguides.
Abstract: Multimode polymer waveguides have been developed to create low-cost, high-speed on-board optical interconnects. Buried optical waveguides made from SU-8 in a polymethyl methacrylate polymer (PMMA) substrate covered with a thin PMMA sheet are a low-cost option for electro-optical interconnects. The propagation losses for a 600 μm×600 μm straight waveguide were 1.96, 1.32, and 1.39 dB/cm, respectively, at three different wavelengths (850, 1310, and 1550 nm). The bending loss for a 15 mm bending radius is as high as 6 dB/cm. Transition and radiation losses dominate overall loss when the bending radius is less than 30 mm. The waveguide was excited using a multimode 850 nm VCSEL transmitter and detected using butt-coupled and lens-coupled receivers. The coupling loss was about 1 dB for the butt-coupling technique and 2 dB for lens coupling. The response bandwidth and the group delay of direct modulated (IF) signal were independent of the channel waveguide for communication speeds up to more than 3 GHz. This technique is viable for low-cost, short-length buried optical waveguides.