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Volume 30, Issue 2
Displaying 1-8 of 8 articles from this issue
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Topical Papers on Recent Trends of Photonic Crystals
Laser Review
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Toshihiko BABA2002 Volume 30 Issue 2 Pages 58
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSDownload PDF (129K) -
Noritsugu YAMAMOTO, Susumu NODA2002 Volume 30 Issue 2 Pages 59-64
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSThree-dimensional photonic crystals with complete photonic bandgap operating at mid-infrared to optical communication wavelengths are developed. The crystal is constructed by stacking semiconductor/air stripes utilizing wafer-fusion and very precise alignment technique based on laser beam diffraction pattern observation. The complete bandgap is observed and the bandgap effect larger than 40 dB is successfully achieved. Photonic crystal waveguide with sharp bend is designed and developed as an important step to realize ultra-small optical integrated circuits.View full abstractDownload PDF (558K) -
Masaya NOTOMI, Akihiko SHINYA, Eiichi KURAMOCHI, Itaru YOKOHAMA, Koji ...2002 Volume 30 Issue 2 Pages 65-69
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSWe study various types of 2D and 3D Si-based photonic crystal structures that are promising for future photonic integrated circuit application. Concerning 2D SOI photonic crystal slabs, we confirm the formation of a wide photonic bandgap in optical communication wavelengths, and realized efficient single-mode line-defect waveguides by structural tuning. Concerning 3D photonic crystals, we use a combination of the lithography technique and autocloning deposition method to realize complicated 3D structures. By using this strategy, we fabricate 3D full gap photonic crystals and 3D/2D hybrid photonic crystals.View full abstractDownload PDF (421K) -
Toshiaki IWAI, Koji FURUNISHI, Katsuhiro ISHII, Kuon INOUE2002 Volume 30 Issue 2 Pages 70-74
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSThe colloidal crystallization of fine particles is a phenomenon of great interest in connection with the research on the fabrication of photonic crystals. This paper describes a newly proposed method, in which self-arrangement and self-assembly of particles are generated under radiation force, i.e. gradient and scattering forces, and capillary force, respectively. The hexagonal structure in the Fourier-transformed patterns of 2D colloidal crystals shows that the triangular lattice structure is successfully fabricated by the proposed method. This paper is concerned with the principle of newly proposed method, capturing and self-arranging particles by radiation pressure, self-assembling particles by the desiccation process, the enlarging of colloid crystal, and the verification of the triangular lattice structure.View full abstractDownload PDF (401K) -
James B. COLE, Shigeki YAMADA, Yoshifumi KATAYAMA2002 Volume 30 Issue 2 Pages 75-80
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSWe have introduced a high accuracy version of the Yee algorithm based on nonstandard finite differences for which the error is ε∼(h/λ)2 compared with ε∼(h/λ)6 for the ordinary one. This high accuracy allows the use of coarse numerical grids, which greatly reduces the computational cost. Realistic two-dimensional calculations can run on a personal computer, while three-dimensional ones can run on a fast workstation. Using this high accuracy algorithm, we developed computational models and methods to simulate optical propagation in photonic crystals, and to compute their transmission spectra, and bandgap structures. In addition, methodologies were developed to accurately represent arbitrary lattice structures on coarse grids.View full abstractDownload PDF (1999K)
Laser Original
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Yutaka HIBINO, Guochun XU, Kunio AWAZU2002 Volume 30 Issue 2 Pages 81-86
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSA novel way for specific immobilization of heparin on polysulfone (PSF) via laser irradiation is summarized. Free Electron Laser (FEL) wavelengths tuned to 6.18 and 6.31 µm, the typical absorption band of carboxyl group of heparin and stretching absorption of aromatic rings in polysulfone respectively, were chosen to illuminate thin heparin film formed on PSF surfaces. The modification at the wavelength of 6.18 µm resulted in surface hydrophilicity and resistance to platelet adhesion. Surface elemental analysis on XPS implied the bounding of heparin on polymer surface. On the contrary, the modification at the wavelength of 6.31 µm showed no statistical difference with controls in terms of hydrophilicity as well as elemental composition. This effect of variation in laser wavelengths is considered as coming from the structural and environmental differences of light-absorbing groups.View full abstractDownload PDF (525K)
Technical Note
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Masahiro SUZUKI, Katsuhiro UNO, Kan-ichi FUJII2002 Volume 30 Issue 2 Pages 87-90
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSAs a method for qualitative judgment of a perfect ball, two faces of the ball are observed at the same time. A horizontal mirror is used in practical examination. Twin Arago points that appear at the center portion in the shadow are used for qualitative estimation of sphericity. The clear concentric-circular fringes, which spread in the whole space between the Arago point and the circumference of the ball, are also an effective way to judge the perfect ball qualitatively. The panchromatic light source provided by a white-light laser gives clearer images than monochromatic laser light source. The color decomposition from the white mode into the monochromatic modes enables visual recognition of the wavelength dependence of the diffraction angle.View full abstractDownload PDF (403K) -
Kazuhiko ISHIKAWA, Katsuhiko ASADA, Kiyoshi TAMAYAMA, Masahiro UEDA2002 Volume 30 Issue 2 Pages 91-93
Published: February 15, 2002
Released on J-STAGE: October 21, 2009
JOURNAL FREE ACCESSAn optical system has been proposed for monitoring the vibration amplitude of a plumbing from a distant position. The system was composed of a sensor head including a white light source, retro-reflector, a CCD camera, and a data processing system including a computer and a display. It was found from the experiment that a commercial CCD camera with an pixel size of 7.4 µm × 7.4 µm, 3.5 × 105 pixels, a camera size of 4.88 mm × 3.6 mm, and a focal length of 51.8 mm is sufficient to obtain a spatial resolution of 0.2 mm for a vibration amplitude in an observed plane of 135 mm in width and 101 mm in height at a distance of 1.43 m from the plumbing. For such a practical applications in a manufacturing plant as a camera position of 10 m from the observed plane, the spatial resolution decreases to 1.4 mm, but the observed plane becomes approximately 942 mm × 707 mm.View full abstractDownload PDF (104K)
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