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.

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: The present invention provides a two-dimensional photonic crystal in which an absolute photonic band gap (PBG), i.e. a photonic band gap that is effective for both the TE-polarized light and the TM-polarized light within a predetermined wavelength range, is created with an adequate bandwidth. The body 21 is provided with holes 22 arranged in a triangular lattice pattern, where the basic shape of the hole is an equilateral triangle. This shaping and arranging of the holes creates an absolute PBG. Each corner of the equilateral triangle is cut along an arc to leave an adequate distance between the neighboring holes (i.e. an adequate width of the connecting portion of the body). This design makes it possible to enlarge each hole 22 while ensuring an adequate strength of the two-dimensional photonic crystal. This construction creates an absolute PBG having a large width.

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: The present invention provides a polarized light mode converter which can be provided within a two-dimensional photonic crystal or can be smoothly connected to a two-dimensional photonic crystal. In a two-dimensional photonic crystal made of a slab-like main body provided with a plurality of different refractive index regions (for example, holes 22) arranged in a lattice in the main body, where the different refractive index regions have a refractive index different from that of the main body, a polarized light conversion waveguide 23 is formed which is comprised of defects of the different refractive index regions arranged linearly whose a cross-sectional shape is asymmetrical in a vertical and in a horizontal direction. The polarized light conversion waveguide 23 can be, for example, realized by providing, on a side of the waveguide, holes 221 and 222 extending in a direction oblique to a the main body surface.

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: The present invention has been made for providing a photonic crystal capable of multiplexing or demultiplexing light within a wavelength band having a certain width. It includes a slab-shaped body 21 provided with plural forbidden band zones 211 and 212, and holes 221 and 222 having different sizes are arranged in the forbidden band zones with different cycles, respectively. Also formed are a trunk waveguide 24 extending along the direction inclined by +30 degrees from a perpendicular of the boundary 23 between the forbidden band zones 211 and 212, and a branch waveguide 25 extending along the direction inclined by ?30 degrees.

Abstract: The present invention provides a diffraction grating light-emitting diode in which the external quantum efficiency is improved by appropriately setting the period of holes when the holes are two-dimensionally periodically formed. A light-emitting diode is configured by laminating, on a sapphire substrate, an n-type GaN layer, an InGaN/GaN active layer, a p-type GaN layer, and a transparent electrode layer. Further, a large number of holes are two-dimensionally periodically formed in the transparent electrode layer, the p-type GaN layer, the InGaN/GaN active layer, and the n-type GaN layer so as to extend in a direction substantially perpendicular to these layers.

Abstract: The present invention is aimed at providing a two-dimensional photonic crystal wavelength multiplexer/demultiplexer capable of multiplexing and demultiplexing both TE and TM-polarized lights. In the wavelength multiplexer/demultiplexer, first and second resonators having the same resonance wavelength ?r are provided between first and second waveguides and which are separately provided in a two-dimensional photonic crystal having a photonic band gap for the TE polarization. A first polarization converter for converting a TM-polarized light to a TE-polarized light is provided on the first waveguide 121 between the first and second resonators and. Similarly, a second polarization converter for converting a TE-polarized light to a TM-polarized light is provided on the second waveguide between the first and second resonators and.

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: 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: A two-dimensional photonic crystal according to the present invention includes a first layer having a dielectric first layer slab in which first layer holes having a refractive index lower than that of the first layer slab are arranged cyclically, a second layer formed on the first layer, including dielectric columns having a refractive index higher than the air arranged in the air with the same cycle as the first layer hole, and a third layer having a dielectric third layer slab in which third layer holes having a refractive index lower than that of the third layer slab are arranged cyclically. Thus, it is possible to obtain the two-dimensional photonic crystal that can create a wider complete PBG than before regardless of the polarization of light and can be manufactured easily.

Abstract: In a double edge triggered flip-flop circuit, a first latch circuit latches input data at either one of rising edge and falling edge of clock signal. A second latch circuit, which is provided in parallel with the first latch circuit, latches the input data at the other of the either one of rising edge and falling edge of the clock signal. At least one of the first latch circuit and the second latch circuit is configured by an SRAM (Static Random Access Memory) type.

Abstract: Holes 12 are created in a slab-shaped body 11. On the first surface 131 of the body 11, the holes 12 are arranged at the lattice points of a triangular lattice 141. On the second surface 132, they are arranged at the lattice points 122 located at positions corresponding to the gravity center of a triangular lattice 141. Three air columns 12A obliquely extend from each lattice point 121 to the nearest three lattice points 122. Similarly, three air columns 12A obliquely extend from each lattice point 122 to the nearest three lattice points 121. In this construction, a periodic structural unit 16 consisting of three holes is created within the body 11 and this unit has a C3v-symmetrical shape at any section 14 parallel to the body 11. Due to this symmetry and the obliquely extending form of the air column 12A, a complete PBG with a large width is obtained. In one embodiment, a broad complete PBG whose width equals 15% of its middle value is obtained.

Abstract: A plurality of third fixed potential lines are wired in parallel. A group of high-potential-side fixed potential lines containing a first fixed potential line and a second fixed potential line are wired in a plurality at predetermined intervals in a direction perpendicular to the third fixed potential line. In a layout region, surrounded by a pair of adjacent third fixed potential lines and a pair of groups of adjacent high-potential-side fixed potential lines, where a first element or a second element is arranged, either one of the first fixed potential line and the second fixed potential line is wired between the pair of third fixed potential lines. In a layout region used for second elements, a second fixed potential line connecting a pair of second fixed potential lines contained respectively in a pair of groups of high-potential-side fixed potential lines that form the layout region is wired between a pair of third fixed potential lines that form the layout region.

Abstract: The present invention provides a polarized light mode converter which can be provided within a two-dimensional photonic crystal or can be smoothly connected to a two-dimensional photonic crystal. In a two-dimensional photonic crystal made of a slab-like main body provided with a plurality of different refractive index regions (for example, holes 22) arranged in a lattice in the main body, where the different refractive index regions have a refractive index different from that of the main body, a polarized light conversion waveguide 23 is formed which is comprised of defects of the different refractive index regions arranged linearly whose a cross-sectional shape is asymmetrical in a vertical and in a horizontal direction. The polarized light conversion waveguide 23 can be, for example, realized by providing, on a side of the waveguide, holes 221 and 222 extending in a direction oblique to a the main body surface.

Abstract: The present invention provides an optical multiplexer/demultiplexer that can be smaller in size and higher in Q-factor or efficiency. This object is achieved by the following construction. In a slab-shaped body 11, low refractive index areas 12 having a refractive index lower than that of the material of the body 11 are periodically arranged to construct a two-dimensional photonic crystal, in which a waveguide 13 is formed by not boring holes 12 linearly. A donor type cluster defect 14 is formed by not boring holes 12 at two ore more lattice points located adjacent to the waveguide 13. With this construction, only a specific wavelength of light included in the light propagating through the waveguide 13 resonates at the donor type cluster 14, and the light thus trapped is released to the outside (demultiplexing). Conversely, only a specific wavelength of light may be introduced through the donor type cluster defect 14 into the waveguide 13 (multiplexing).

Abstract: The present invention has been made for providing a photonic crystal capable of multiplexing or demultiplexing light within a wavelength band having a certain width. It includes a slab-shaped body 21 provided with plural forbidden band zones 211 and 212, and holes 221 and 222 having different sizes are arranged in the forbidden band zones with different cycles, respectively. Also formed are a trunk waveguide 24 extending along the direction inclined by +30 degrees from a perpendicular of the boundary 23 between the forbidden-band zones 211 and 212, and a branch waveguide 25 extending along the direction inclined by ?30 degrees.

Abstract: The present invention is aimed at providing a two-dimensional photonic crystal wavelength multiplexer/demultiplexer capable of multiplexing and demultiplexing both TE and TM-polarized lights. In the wavelength multiplexer/demultiplexer, first and second resonators and having the same resonance wavelength ?r are provided between first and second waveguides and which are separately provided in a two-dimensional photonic crystal having a photonic band gap for the TE polarization. A first polarization converter for converting a TM-polarized light to a TE-polarized light is provided on the first waveguide 121 between the first and second resonators and. Similarly, a second polarization converter for converting a TE-polarized light to a TM-polarized light is provided on the second waveguide between the first and second resonators and.

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.