Abstract: An objective of the present invention is to provide a two-dimensional photonic crystal in which a complete photonic band gap (PBG), i.e. a photonic band gap that is effective for both a TE-polarized light and a TM-polarized light within a predetermined wavelength range, is created and an adequate width of the complete PBG can be ensured. A slab-shaped body 21 consisting of a birefringent material is provided with holes 22 periodically arranged in a triangular lattice pattern, where a plane shape of the hole is an equilateral triangle. The PBG for the TE-polarized light and the PBG for the TM-polarized light can be independently set by adjusting anisotropy in the refractive index of the body 21, i.e. a refractive index in a direction vertical to the body 21 and a refractive index in a direction parallel to the body 21. This construction makes it possible to ensure an adequate width of the complete PBG.

Abstract: A front cover (1) is engaged with a plate-like slide mounting bracket (3b), a liquid crystal panel (2) is fixed to the front cover (1) by a panel contact portion (31) of the slide mounting bracket (3b), and a back cover (5) is fixed to the front cover (1) through the plate-like slide mounting bracket (3b) by screwing a screw into a tapped hole (33). As a result, it is possible to narrow a width (b) which is obtained by subtracting a width of an overlap portion of the liquid crystal display panel (2) from a width (B) of a frame portion of the front cover (1) because no fixing boss for mounting the back cover (5) is required for the front cover (1). Consequently, the frame of the front cover (1) can be narrowed.

Abstract: A method and system of refining natural gas that improves the quality of liquefied natural gas and enables separation and recovery of hydrocarbons other than methane. The method of refining natural gas containing methane; any other hydrocarbon selected from the group consisting of ethane, ethylene, propane, propylene, n-butane, isobutane, 1-butene, n-pentane, and isopentane; carbon dioxide; and hydrogen sulfide, includes adjusting a pressure and temperature of the natural gas so that the methane is in the gas phase, the other hydrocarbon in the liquid phase, and the carbon dioxide and the hydrogen sulfide in the solid phase, respectively; separating the natural gas, of which the pressure and temperature has been adjusted, into a gas containing the methane and a suspension liquid; and separating the separated suspension liquid into a liquid containing the other hydrocarbon and a solid containing the carbon dioxide and the hydrogen sulfide.

Abstract: In 2D photonic crystals, cavities having a heightened Q factor are made available, wherein combining the high Q cavities with waveguides affords channel add/drop filters having high resolution. In a cavity constituted by a point defect within a 2D photonic crystal, the 2D photonic crystal is configured by an arrangement, in a two-dimensional lattice of points defined in a slab (1), of low-refractive-index substances (2) having a low refractive index relative to the slab (1) and being of identical dimension and shape. The point defect (4) contains a plurality of three or more lattice points that neighbor one another, and in these lattice points no low-refractive-index substances (2) are arranged; therein the dimension of the low-refractive-index substance (2) that should be arranged to correspond to at least one of the lattice points nearest the point defect (4) is dimensionally altered from a predetermined dimension.

Abstract: A semiconductor device includes a first wiring layer, a second wiring layer and a third wiring layer. The first wiring layer is formed on a semiconductor substrate. The second and the third wiring layer wiring layers are arranged in a direction intersecting with the first wiring layer on respective sides of the wiring layer. An air bridge wiring intersects the second and third wiring layers sandwiching an air layer above the first wiring layer therewith. The overall shape of the air bridge wiring has an upward convex curvature in an arch shape and the transverse sectional shape of the air bridge wiring is in the form of a downward concave curvature.

Abstract: A highly sensitive and compactible target substance sensor for detection of the target substance using a photonic crystal and a method thereof are provided. The sensor of the present invention includes an electromagnetic wave source of supplying an electromagnetic wave, a photonic sensor element, and a detector. The photonic sensor element has photonic crystalline structure and is configured to include a sensor waveguide for introducing the electromagnetic wave, and a sensing resonator electromagnetically coupled to the sensor waveguide for resonating the electromagnetic wave at specific wavelength. The sensing resonator is exposed to an atmosphere including the target substance so as to vary a characteristic of the electromagnetic wave emitted from the sensing resonator. The detector is configured to receive the electromagnetic wave emitted from the sensing resonator to recognize an intensity variation of the electromagnetic wave and issue a signal indicative of a characteristic of the target substance.

Abstract: An object of the present invention is to provide a two-dimensional photonic crystal which can be used for optical path changeover switches or the like to allow switching of a path. A first area 121 and a second area 122 provided with holes 131 and 132 having a difference in the period and size are created on a body 11, and a main waveguide 15 is formed to obliquely cross a boundary 14 between these areas. A branch waveguide 17 branched from the main waveguide 15 into the first area 121 side is also formed by using a crossing point between the main waveguide 15 and the boundary 14 as a starting point. The second area 122 is heated to change a refractive index of the body within the area, so that a frequency band which can be passed through the main waveguide 15 of the second area 122 is changed.

Abstract: A plurality of flip-flop circuits, having different circuit configurations, which perform an identical digital signal processing are mixed on a single semiconductor substrate. A first flip-flop circuit among the plurality of flip-flop circuits receives a clock signal supplied from outside the flip-flop circuits, through at least two stage inverters, and operates with clock signals outputted from the inverters. A second flip-flop circuit receives the clock signal supplied from outside the flip-flop circuits through at least one inverter having a less number of stages than the number of stages of the inverter contained in the first flip-flop circuit, and operates with at least one of the clock signal and a clock signal outputted from the inverter.

Abstract: An object of the present invention is to provide a multiplexer/demultiplexer capable of preventing a decrease in multiplexing/demultiplexing efficiency due to an error in wavelength or due to a crosstalk with other wavelengths. A two-dimensional photonic crystal having holes 22 cyclically arranged is provided with an input waveguide 23 and an output waveguide 24. Located between the two waveguides are two point-like defects 25 and 26, each consisting of a region devoid of the holes 22. From the light including various wavelengths and propagating through the input waveguide 23, the two point-like defects extract a ray of light having a wavelength determined by the shape of the point-like defects and introduce it into the output waveguide 24.

Abstract: The present invention aims to provide a two-dimensional photonic crystal having an optical resonator, which allows the control of the front/back emission ratio of light. To achieve this object, a refractive index member made of a material having a refractive index different from that of air is mounted on a two-dimensional photonic crystal having a body in which holes are periodically arranged. In this construction, the body and the refractive index member cooperatively function as an optical resonator located at the position where the refractive index member is mounted. The light emitted from this optical resonator is stronger on the side having a higher refractive index, i.e. on the side where the refractive index member is mounted. Accordingly, the light emitted from the side where the refractive index member is mounted is stronger than the light emitted from the other side. The ratio of the emission intensity of the two rays of light and, i.e.

Abstract: The present invention intends to provide a two-dimensional photonic crystal having a high level of mechanical strength and functioning as a high-efficiency resonator. The two-dimensional photonic crystal according to the present invention includes a slab layer 31 under which a clad layer 32 is located. In the slab layer 31, areas 35 having a refractive index different from that of the slab layer 31 are cyclically arranged to create a two-dimensional photonic crystal. A portion of the cyclic arrangement of the areas 35 are omitted to form a point-like defect 36. This defect 36 functions as a resonator at which a specific wavelength of light resonates. An air-bridge cavity 37 facing the point-like defect 36 is formed over a predetermined range of the clad layer 32. In this construction, the clad layer 32 supports the slab layer 31 except for the range over which the air-bridge space 37 is formed. Therefore, the two-dimensional photonic crystal has a high level of mechanical strength.

Abstract: A chassis has positioning plates which are perpendicular to each other formed by cutting and bending a plate material, attachment convex portions which are formed by press work of the plate material, and which are projected out in bending direction of the positioning plates, and L-shaped attachments. Aboard has a pair of slits into which a pair of the positioning plates inserted, and attachment holes. The board is positioned in two directions by a pair of the positioning plates, thereby the board can be positioned with a high degree of accuracy.

Abstract: An object of the present invention is to provide a two-dimensional photonic crystal in which conditions for both the TE-polarized light and the TM-polarized light can be easily satisfied. A body includes a first area having a triangular lattice pattern arrangement of a circular hole and a second area having a triangular lattice pattern arrangement of an equilateral triangular holes. Therefore, the TE-PBG which is a photonic band gap (PBG) for the TE-polarized light is created in the first area, and the TM-PBG which is a PBG for the TM-polarized light is created in the second area. Parameters such as the period and size of the holes can be independently set for the first area and the second area, so that an energy region common to the TE-PBG and the TM-PBG (i.e. absolute PBG) can be made larger and easily created.

Abstract: An objective of the present invention is to provide a two-dimensional photonic crystal in which a complete photonic band gap (PBG), i.e. a photonic band gap that is effective for both a TE-polarized light and a TM-polarized light within a predetermined wavelength range, is created and an adequate width of the complete PBG can be ensured. A slab-shaped body 21 consisting of a birefringent material is provided with holes 22 periodically arranged in a triangular lattice pattern, where a plane shape of the hole is an equilateral triangle. The PBG for the TE-polarized light and the PBG for the TM-polarized light can be independently set by adjusting anisotropy in the refractive index of the body 21, i.e. a refractive index in a direction vertical to the body 21 and a refractive index in a direction parallel to the body 21. This construction makes it possible to ensure an adequate width of the complete PBG.

Abstract: A two-dimensional photonic crystal slab having a photonic band gap common to a light beam in the TE-like mode and a light beam in the TM-like mode includes a slab member containing a high refractive index material and low refractive index sectors, arranged in the slab member in a triangular pattern, having a triangular prism shape. The two-dimensional photonic crystal slab further includes a linear defect section that is a disordered portion in a periodic structure of a photonic crystal and extends in the ?-J direction. Light beams in the TE-like mode and light beams in the TM-like mode can be propagated through the waveguide section. A two-dimensional photonic crystal waveguide includes the two-dimensional photonic crystal slab.

Abstract: The present invention intends to provide a two-dimensional photonic crystal having a high level of mechanical strength and functioning as a high-efficiency resonator. The two-dimensional photonic crystal according to the present invention includes a slab layer 31 under which a clad layer 32 is located. In the slab layer 31, areas 35 having a refractive index different from that of the slab layer 31 are cyclically arranged to create a two-dimensional photonic crystal. A portion of the cyclic arrangement of the areas 35 are omitted to form a point-like defect 36. This defect 36 functions as a resonator at which a specific wavelength of light resonates. An air-bridge cavity 37 facing the point-like defect 36 is formed over a predetermined range of the clad layer 32. In this construction, the clad layer 32 supports the slab layer 31 except for the range over which the air-bridge space 37 is formed. Therefore, the two-dimensional photonic crystal has a high level of mechanical strength.

Abstract: In this electromagnetic wave frequency filter, an electromagnetic wave of a predetermined frequency matching a resonant frequency of a resonator 41 is transmitted from an input waveguide 2 to an output waveguide 3 through the resonator 41, and is outputted from a drop port P31. This filter has an input-waveguide-side reflector 211 and an output-waveguide-side reflector 311, which reflect the electromagnetic wave of the predetermined frequency. The electromagnetic wave frequency filter satisfies the following relation: Qinb/(1?cos ?1)<<Qv, Qinb/(1?cos ?1)=Qinr/(1?cos ?2), ?1, ?2?2N?(N=0, 1, . . .

Abstract: The present invention intends to provide a two-dimensional photonic crystal having a wide photonic band gap (PBG). In a slab-shaped body 31, a number of holes 32, whose sectional shape on a plane parallel to the slab surface is an equilateral triangle, are periodically arranged in a triangular lattice pattern. The upper and lower sides of the holes 32 are covered with the material of the body 31. The aforementioned sectional shape is uneven along the direction perpendicular to the slab surface. This construction expands the PBG for TM-polarized light and thereby increases its energy region overlapping with the PBG for TE-polarized light. This overlapping section is the complete PBG. If a ray of light whose wavelength corresponds to an energy level within the complete PBG, neither the TE-polarized nor TM-polarized component of the light can be propagated through the photonic crystal.

Abstract: An object of the present invention is to provide a two-dimensional photonic crystal which can be used for optical path changeover switches or the like to allow switching of a path. A first area 121 and a second area 122 provided with holes 131 and 132 having a different in the period and size are created on a body 11, and a main waveguide 15 is formed to obliquely cross a boundary 14 between these areas. A branch waveguide 17 branched from the main waveguide 15 into the first area 121 side is also formed by using a crossing point between the main waveguide 15 and the boundary 14 as a starting point. The second area 122 is heated to change a refractive index of the body within the area, so that a frequency band which can be passed through the main waveguide 15 of the second area 122 is changed.

Abstract: The present invention intends to provide a two-dimensional photonic crystal resonator having a high Q-value. The slab-shaped body 21 is provided with cyclically arranged holes 22. The body 21 is divided into three areas 31-33 with the holes 22 arranged with cycle distances of a1 in area 31 and a2 in areas 32 and 33, which is smaller than a1. A waveguide 23 passing through the three areas is formed by linearly eliminating the holes 22. The waveguide 23 thus formed can propagate rays of light within a wavelength band that depends on the cycle distance of the holes 22. The cycle distance of the holes in the area 31 differs from that of the areas 32 and 33, and the wavelength band of the light propagating through the waveguide accordingly differs.