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[Keyword] surface(404hit)

201-220hit(404hit)

  • Surface Waves along a Boundary of Single Negative Material

    Masashi HOTTA  Mitsuo HANO  Ikuo AWAI  

     
    LETTER-Microwaves, Millimeter-Waves

      Vol:
    E88-C No:2
      Page(s):
    275-278

    Existence of a surface wave along the boundary between the semi-infinite materials, one of which is a free-space and the other is a material with either negative permeability or negative permittivity, is theoretically investigated. Surface waves exist in only limited combination of negative and positive signs of the material parameters. In addition, by analyzing the surface wave in a finite-thickness slab with negative permeability, its mode profile has been obtained for two different types of symmetry. From these results, the present paper predicts the possibility of a surface wave directional coupler based on a single slab transmission along its top and bottom surfaces.

  • Analysis of Adsorbing Molecules on Pt Surface Using Electrochemical Impedance Spectroscopy

    Kenshi HAYASHI  Kosuke HAYAMA  Kumi MASUNAGA  Wataru FUTAGAMI  Seung-Woo LEE  Kiyoshi TOKO  

     
    PAPER-Bioelectronic and Sensor

      Vol:
    E87-C No:12
      Page(s):
    2087-2092

    Chemical sensor which can be used for a multi-purpose chemical measurement to detect various chemical substances with a small number of a sensor array was investigated. It was confirmed that chemical compounds adsorbed strongly and irreversibly on a platinum surface using conventional electrochemical methods and an instrumental surface analysis. The adsorbates were also analyzed by means of an electrochemical impedance spectroscopy under dynamic potential scan; measured impedance reflects CPE (constant phase element) properties of the electrode surface. The method provides a convenient technique for the surface analysis of adsorbing chemicals. The CPE response profile was modified through chemical adsorption/desorption and the interaction between the polarized surface and chemical substances. Consequently, various profiles depending on chemical substances were obtained and it had quantitative and qualitative information about chemicals interacting with the surface. The present method which does not require a specific electrochemical reaction can be applied for multi-purpose chemical sensors and also simple chemical analyses.

  • Backlight Unit with Double Surface Light Emission Using a Single Micro-Structured Light-Guide Plate

    Kalil KALANTAR  Shingo MATSUMOTO  Tatsuya KATOH  Toshiyuki MIZUNO  

     
    INVITED PAPER

      Vol:
    E87-C No:11
      Page(s):
    1954-1961

    A double surface light emission backlight that uses single light-guide plate, has been developed for illumination of two liquid-crystal displays (LCD) on its front and rear, to be used in a cellular phone. The light-guide plate has a trapezoid cross-section with arrays of optical micro deflector and micro prism on the front and the rear surfaces, respectively. Propagated light, forward and backward, inside the light-guide plate are controlled and directed toward LCDs using only two prism sheets with internal reflection characteristic, each for the front and the rear. Only three optical components and four light-emitting diodes (LEDs) are used in the new structure compared with ten components and six LEDs of the current type. Comparing with the current type, the thickness and power consumption of the new backlight are reduced by a factor of 0.59 and 0.67, respectively.

  • Shrink-Wrapped Boundary Face (SWBF) Algorithm for Mesh Reconstruction from Unorganized 3D Points

    Young-Kyu CHOI  Bon-Ki KOO  Byoung-Tae CHOI  

     
    LETTER-Computer Graphics

      Vol:
    E87-D No:9
      Page(s):
    2283-2285

    A new mesh reconstruction method, called the shrink-wrapped boundary face (SWBF) algorithm, is proposed for approximating a surface from a set of unorganized 3D points. SWBF overcomes the genus-0 spherical topology restriction of previous shrink-wrapping based mesh generation technique. Furthermore, SWBF is much faster since it requires only local nearest-point-search in the shrinking process. Our experimental results demonstrate that SWBF is very robust and efficient, and it is expected to become a general solution for reconstructing a mesh from an unorganized points cloud.

  • The 3D Measurement and Analysis of High Precision Surfaces Using Con-Focal Optical Methods

    John McBRIDE  Christian MAUL  

     
    INVITED PAPER

      Vol:
    E87-C No:8
      Page(s):
    1261-1267

    The paper reviews methods for the measurement and analysis of high precision surfaces. A number of measurement techniques are discussed with the emphasis on the application of con-focal methods. The various techniques are compared in terms of measurement times, data density, and the ability to detect near vertical surfaces, and steps. The two sensing methods discussed are the auto-focus laser method and the white light methods. Particular applications considered are in the measurement of eroded electrical contact surfaces, spherical and near spherical surfaces, and MEMS. The particular emphasis here is on the metrology of such surfaces and devices and methods for the assessment of complex micro-machined surfaces. The paper points to a number of directions for improved metrology and discusses these in the context of the application given.

  • Design Optimization Methodology for On-Chip Spiral Inductors

    Kenichi OKADA  Hiroaki HOSHINO  Hidetoshi ONODERA  

     
    PAPER

      Vol:
    E87-C No:6
      Page(s):
    933-941

    This paper presents a methodology for optimizing the layout of on-chip spiral inductors using structural parameters and design frequency in a response surface method. The proposed method uses scattering parameters (S-parameter) to express inductor characteristics, and hence is independent of spiral geometries and equivalent circuit models. The procedure of inductor optimization is described, and a design example is presented.

  • A Novel Approach to Sampling the Coiled Tubing Surface with an Application for Monte Carlo Direct Lighting

    Chung-Ming WANG  Peng-Cheng WANG  

     
    PAPER-Computer Graphics

      Vol:
    E87-D No:6
      Page(s):
    1545-1553

    Sampling is important for many applications in research areas such as graphics, vision, and image processing. In this paper, we present a novel stratified sampling algorithm (SSA) for the coiled tubing surface with a given probability density function. The algorithm is developed from the inverse function of the integration for the areas of the coiled tubing surface. We exploit a Hierarchical Allocation Strategy (HAS) to preserve sample stratification when generating any desirable sample numbers. This permits us to reduce variances when applying our algorithm to Monte Carlo Direct Lighting for realistic image generation. We accelerate the sampling process using a segmentation technique in the integration domain. Our algorithm thus runs 324 orders of magnitude faster when using faster SSA algorithm where the order of the magnitude is proportional to the sample numbers. Finally, we employ a parabolic interpolation technique to decrease the average errors occurred for using the segmentation technique. This permits us to produce nearly constant average errors, independent of the sample numbers. The proposed algorithm is novel, efficient in computing and feasible for realistic image generation using Monte Carlo method.

  • Surface Deformation Displays for Virtual Environment Using the Fuzzy Model

    MinKee PARK  Hideki HASHIMOTO  

     
    PAPER

      Vol:
    E87-D No:6
      Page(s):
    1422-1432

    In this paper, a new method for displaying a surface deformation is proposed to provide sufficient realism in virtual environment. The approach selected in this paper is based on the fuzzy model and it is sufficient that only one additional rule be added to the fuzzy model to display a surface deformation. Furthermore, designers can easily determine which parameters should be used and how much they should be changed in order to alter shapes as required. The proposed method, thus, is a simple, but effective technique that can also be applied to real time operation and makes it possible to act on several surface points simultaneously. The results of the computer simulation are also given to demonstrate the validity of the proposed algorithm.

  • Two-Sapphire-Rod-Resonator Method to Measure the Surface Resistance of High-Tc Superconductor Films

    Toru HASHIMOTO  Yoshio KOBAYASHI  

     
    PAPER-General Methods, Materials, and Passive Circuits

      Vol:
    E87-C No:5
      Page(s):
    681-688

    Precise designs are presented for sapphire rod resonators of three types, which have been proposed by the IEC/TC90/WG8 in the standard measurement method of the surface resistance Rs of high-Tc superconductor (HTS) films; an open-type, a cavity-type and a closed-type. In order to separate TE011 and TE013 modes, which are used in Rs measurements, from the other modes, appropriate dimensions for these three resonators are determined from mode charts calculated from a rigorous analysis based on the mode matching method, taking account of an uniaxial-anisotropic characteristic of sapphire. Comparison of the open-type resonator with the closed-type is performed. For the open-type, the unloaded Q values of both the TE011 and TE013 modes are reduced by radiations of a leaky state TM310 mode. Finally, validity of the design and a two-sapphire-rod-resonator method will be verified by experiments.

  • Experimental Study of Non-specular Wave Scattering from Building Surface Roughness for the Mobile Propagation Modeling

    Hary BUDIARTO  Kenshi HORIHATA  Katsuyuki HANEDA  Jun-ichi TAKADA  

     
    PAPER-Antenna and Propagation

      Vol:
    E87-B No:4
      Page(s):
    958-966

    In the urban area, buildings are the main scatterer which dominate the mobile propagation characteristics. However, reflection, diffraction, and scattering on the building surfaces in the radio environment induce undesirable multipath propagation. Multipath prediction with respect to a building surface has been conventionally based on an assumption that reflection from the surface has a substantial specular direction. However non-specular scattering from the building surface can affect the channel characteristics as well as specular scattering. This paper presents multipath characteristics of non-specular wave scattering from building surface roughness based on the experimental results. Superresolution method was applied as an approach to handle the signal parameters (DoA, ToA) of the individual incoming waves reflected from building surface roughness. The results show that the multipaths can be detected at many scatterers, such as ground, window's glass, window's frames and bricks surface, as well as directly from the transmitter. Most of the scattered waves are arriving closely from specular directions. The measured reflection coefficients were well bounded by reflection coefficients of the theoretically smooth and random rough surface. The Fresnel reflection coefficient formula, considering the finite thickness of the building surface and Gaussian scattering correction, give better prediction for glass and bricks reflection coefficient measurement.

  • High Index-Contrast 2D Photonic Band-Edge Laser

    Soon-Hong KWON  Yong-Hee LEE  

     
    INVITED PAPER

      Vol:
    E87-C No:3
      Page(s):
    308-315

    Free-standing 2D slab photonic band-edge lasers based on square lattice and triangular lattice are realized by optical pumping at room-temperature. Both in-plane-emission and surface-emission photonic band-edge lasers are observed and compared. Analyses on optical loss mechanisms for finite-size photonic band-edge lasers are also discussed.

  • All-Optical Regeneration Using a Vertical-Cavity Surface-Emitting Laser with External Light Injection

    Yutaka ONISHI  Fumio KOYAMA  

     
    PAPER-Lasers, Quantum Electronics

      Vol:
    E87-C No:3
      Page(s):
    409-415

    We propose a novel optical signal processing using an optically pumped vertical-cavity surface-emitting laser (VCSEL) with an external light input. The mode transition between a fundamental and a 1st-high-order transverse mode is induced by an external light injection. Since a single mode fiber (SMF) spatially selects a fundamental transverse mode as an output signal, we are able to realize a nonlinear transfer function, which will be useful in future photonic networks. The mode transition characteristic of a 1.55 µm optically pumped two-mode VCSEL has been simulated by using a two-mode rate equation, which includes the effects of spatial hole burning and spectral hole burning as gain saturation coefficients. We focus on the detuning effect in the injection locking. When the wavelength of an input light with a fundamental mode is slightly longer than that of a VCSEL operating in a 1st-high-order transverse mode, the transverse mode of the VCSEL is switched to a fundamental mode at a critical input power level. This gives us an ideal transfer function for 2R (reamplification and reshaping) regeneration. Also, the proposed scheme may enable polarization insensitive signal processing, which is a unique feature in surface emitting lasers.

  • Finite-Difference Time-Domain Simulation of Two-Dimensional Photonic Crystal Surface-Emitting Laser Having a Square-Lattice Slab Structure

    Mitsuru YOKOYAMA  Susumu NODA  

     
    PAPER

      Vol:
    E87-C No:3
      Page(s):
    386-392

    By means of the three-dimensional (3D) finite-difference time domain (FDTD) method, we have investigated in detail the optical properties of a two-dimensional photonic crystal (PC) surface-emitting laser having a square-lattice structure. The 3D-FDTD calculation is carried out for the finite size PC slab structure. The device is based on band-edge resonance, and plural band edges are present at the corresponding band edge point. For these band edges, we calculate the mode profile in the PC slab, far field pattern (FFP) and polarization mode of the surface-emitted component, and photon lifetime. FFPs are shown to be influenced by the finiteness of the structure. Quality (Q) factor, which is a dimensionless quantity representing photon lifetime, is introduced. The out-plane radiation loss in the direction normal to the PC plane greatly influences the total Q factor of resonant mode and is closely related with the band structure. As a result, Q factors clearly differ among these band edges. These results suggest that these band edges include resonant modes that are easy to lase and resonant modes that are difficult to lase.

  • Investigation of Single Monolayer Formation of the Evaporated Liquid Crystalline Molecules by the Surface Potential Measurement

    Takaaki MANAKA  Hajime HIGA  Dai NAKAMURA  Dai TAGUCHI  Mitsumasa IWAMOTO  

     
    LETTER-Nano-interface Controlled Electronic Devices

      Vol:
    E87-C No:2
      Page(s):
    183-184

    The formation of single monolayer of liquid crystalline molecules, 4-n-pentyl-4-cyanobiphenyl (5CB), deposited by the evaporation method in the air, was confirmed with the surface potential measurement. The surface potential increased with the time of evaporation, and the 3- or 4-minute evaporation at a source temperature of 110 gave the saturated potential, indicating the formation of single monolayer. Single monolayer formation was also supported by the comparison of the UV-visible absorption for evaporated film with LB monolayer. Positive potentials were built at the surface, indicating that CN group faces the substrate.

  • Fabrication of La-Doped YBCO and SrTiO3-Buffered LSAT Thin Films for Ramp-Edge Josephson Junctions on Superconducting Ground Plane

    Seiji ADACHI  Hironori WAKANA  Yoshihiro ISHIMARU  Masahiro HORIBE  Yoshinobu TARUTANI  Keiichi TANABE  

     
    PAPER

      Vol:
    E87-C No:2
      Page(s):
    206-211

    The deposition conditions of Y0.9Ba1.9La0.2Cu3Oy (La-YBCO) and (LaAlO3)0.3-(SrAl0.5Ta0.5O3)0.7 (LSAT) thin films were studied with the aim of fabricating ramp-edge Josephson junctions on a superconducting ground plane. These films were deposited by a magnetron sputtering method and utilized as a base electrode and an insulating layer under the electrode, respectively. YBa2Cu3Oy thick films grown by liquid phase epitaxy (LPE-YBCO) were used for a ground plane. Insertion of a SrTiO3 buffer layer between LSAT and LPE-YBCO significantly improved the flatness of the film surface. La-YBCO films with a flat surface and Tc (zero) of 87K were reproducibly obtained by DC sputtering. We have fabricated ramp-edge Josephson junctions using these films. Resistively and capacitively shunted junction (RCSJ)-like characteristics were observed in them. An Ic spread of 10.2% (at 4.2K, average Ic = 0.5 mA) was obtained for a 1000-junction series-array.

  • 3D Human Whole Body Construction by Contour Triangulation

    Bon-Ki KOO  Young-Kyu CHOI  Sung-Il CHIEN  

     
    PAPER-Computer Graphics

      Vol:
    E87-D No:1
      Page(s):
    233-243

    In the past decade, significant effort has been made toward increasing the accuracy and robustness of three-dimensional scanning methods. In this paper, we present a new prototype vision system named 3D Model Studio, which has been built to reconstruct a complete 3D model in as less as a few minutes. New schemes for a probe calibration and a 3D data merging (axis consolidation) are employed. We also propose a new semi-automatic contour registration method to generate accurate contour model from 3D data points, along with a contour triangulation based surface reconstruction. Experimental result shows that our system works well for reconstructing a complete 3D surface model of a human body.

  • Quadratic Surface Reconstruction from Multiple Views Using SQP

    Rubin GONG  Gang XU  

     
    PAPER-Image Processing, Image Pattern Recognition

      Vol:
    E87-D No:1
      Page(s):
    215-223

    We propose using SQP (Sequential Quadratic Programming) to directly recover 3D quadratic surface parameters from multiple views. A surface equation is used as a constraint. In addition to the sum of squared reprojection errors defined in the traditional bundle adjustment, a Lagrangian term is added to force recovered points to satisfy the constraint. The minimization is realized by SQP. Our algorithm has three advantages. First, given corresponding features in multiple views, the SQP implementation can directly recover the quadratic surface parameters optimally instead of a collection of isolated 3D points coordinates. Second, the specified constraints are strictly satisfied and the camera parameters and 3D coordinates of points can be determined more accurately than that by unconstrained methods. Third, the recovered quadratic surface model can be represented by a much smaller number of parameters instead of point clouds and triangular patches. Experiments with both synthetic and real images show the power of this approach.

  • A Uniform and Dense Microwave Plasma

    Kazuaki SENDA  Koutarou UMEHARA  Yuichi SAKAMOTO  

     
    PAPER-Plasma

      Vol:
    E86-C No:12
      Page(s):
    2479-2481

    Based on an experimental fact that surface wave plasmas excited by strongly coupled microwave through thin dielectric windows show nearly perfect absorption of microwave and, after diffusion, form a widely uniform dense plasma. A plasma with an uniformity of 5% over an area of 50 cm 60 cm was produced. The plasma produced by application of 2400 W total microwave power gives 1 1011 cm-3 in density and 1.5 eV in electron temperature.

  • A Global Optimization Method for Remeshing Polygonal Surface of Arbitrary Topological Type

    Jaemin KIM  Moongoo KANG  Seongwon CHO  

     
    LETTER-Algorithms

      Vol:
    E86-D No:11
      Page(s):
    2475-2478

    This article describes a new method for converting an arbitrary topology mesh into one having subdivision connectivity. First, a base mesh is produced by applying a sequence of edge collapse operations to the original mesh with irregular connectivity. Then, the base mesh is iteratively subdivided. Each subdivided mesh is optimized to reduce its distance from the original mesh and to improve its global smoothness and compactness. A set of corresponding point pairs, which is required to compute the distance from the original mesh to the subdivided mesh, is determined by combining the initial parameterization and the multi-resolution projection. Experimental results show that the proposed method yields good performance in terms of global smoothness, small distortion, and good compactness, compared with conventional methods.

  • 26 GHz Bandpass Filter and Duplexer Using TM11δ Mode Dielectric Resonators with High-Q Performance and Compact Configuration

    Akira ENOKIHARA  Hideki NANBA  Toshiaki NAKAMURA  Kojiro OKUYAMA  Toshio ISHIZAKI  Tomoki UWANO  

     
    PAPER-Microwaves, Millimeter-Waves

      Vol:
    E86-C No:11
      Page(s):
    2283-2291

    26 GHz bandpass filter and duplexer using TM11δ rectangular-mode dielectric cavity resonators are proposed. These have a configuration compact and suitable for mounting on circuit boards. The resonators consisting of the Ba(Mg,Ta)O3 ceramic material showed a high quality factor value of 2600, which is roughly comparable to that of conventional E-plane waveguide filters. The dielectric losses of the ceramic material were experimentally evaluated from the viewpoint of the high frequency operation and the dielectric loss tangent of 7.410-5 was observed at 20 GHz. A three-stage Tchebyscheff bandpass filter with 0.4% relative bandwidth was fabricated and the passband insertion loss was 1.7 dB. A duplexer designed with two TM11δ mode filters and a microstrip T-junction is also presented.

201-220hit(404hit)