Abstract: The semiconductor device of the present invention comprises an optical transmission region, and a light receiving part for converting light propagating through the optical transmission region to an electrical signal, wherein the optical transmission region comprises a two-dimensional optical waveguide layer, and wherein at least a portion of the light receiving part is embedded in the optical transmission region, whereby the present invention can provide a semiconductor device having reduced direction dependency when light propagating through the optical transmission region is received.

Abstract: In a layered board, an insulating layer is interposed between a first layer capable of transmitting an electrical signal or an optical signal and a second layer capable of transmitting the electrical signal or the optical signal, interconnection of the signal between the first layer and the second layer is established through a signal connecting path penetrating the insulating layer, and the signal connecting path has both a function of transmitting the electrical signal and a function of transmitting the optical signal.

Abstract: An electronic circuit board having an optical wiring layer sandwiched between two electrical wiring layers. The optical wiring layer is structured to be a two-dimensional optical waveguide. An E/O device and an O/E device are provided in the optical wiring layer or at an interface between the optical wiring layer and the electrical wiring layer. A via piercing the optical wiring layer connects the two electrical wiring layers. It is possible to efficiently input and output light to and from an optical wiring layer.

Abstract: Disclosed herein is an aluminum hydroxide having specific characteristics, and a tire tread rubber composition and a pneumatic tire employing the aluminum hydroxide, which allow grip performance and abrasion resistance to increase and rolling resistance to decrease and are superior in processibility. The aluminum hydroxide has a loosed bulk density of not more than 0.60 g/cm3, a DOP oil absorption of at least 70 cm3/100 g and less than 250 cm3/100 g, and a BET specific surface area of at least 30 m2/g and less than 350 m2/g. 5-150 parts by weight of the aluminum hydroxide is blended with 100 parts by weight of a rubber component to obtain the tire tread rubber composition. The rubber component preferably includes at least 60 parts by weight of styrene-butadiene rubber having a styrene content of 20-60% by weight.

Abstract: An optoelectric integrated device includes a three-dimensional solid semiconductor crystal, such as a silicon ball, and a plurality of optical devices including a light-emitting device and a light-receiving device integrated on the surface of the semiconductor crystal. Light is emitted and received between the light-emitting device and the light-receiving device through the interior of the semiconductor crystal used as an optical wiring medium.

Abstract: A rubber composition which can improve performance on icy and snowy road sufficiently and a tire using the same. The rubber composition comprises 2 to 30 parts by weight of staple fibers having an average fiber diameter of 10 to 100 &mgr;m and an average fiber length of 0.01 to 4 mm, and 1 to 10 parts by weight of particles having a Moh's hardness of at least 5 and an average particle size of at most 500 &mgr;m based on 100 parts by weight of a diene rubber. The tire of the present invention is prepared by using the rubber composition for tread. Examples of the particle are pumice, quarts, emery and the like.

Abstract: To provide a rubber composition for breaker having balanced properties among rigidity, heat resistance, adhesiveness, humid aging adhesion and elongation, and a pneumatic tire having a breaker layer or a belt layer comprising the rubber composition. A rubber composition for breaker comprises 55 to 65 parts by weight of carbon black, 5 to 15 parts by weight of silica, 3.5 to 4.5 parts by weight of sulfur, at least 0.08 part by weight of cobalt, a resorcinol resin and a methylene donor based on 100 parts by weight of a rubber component containing a natural rubber and/or an isoprene rubber as a main component.

Abstract: A pneumatic tire having at least one layer of carcass, an inner liner made of a rubber composition (a) comprising a rubber component (a′) consisting essentially of 60 to 95% parts by weight of a halogenated butyl rubber and 5 to 40% by weight of a regular butyl rubber, and a rubber layer located between the carcass and the inner liner, which made of a rubber composition (b) comprising a diene rubber, sulfur and a sulphenamide vulcanization accelerator; the amount of sulfur in the rubber composition (b) being represented by the equation (I):

Abstract: The semiconductor device of the present invention comprises an optical transmission region, and a light receiving part for converting light propagating through the optical transmission region to an electrical signal, wherein the optical transmission region comprises a two-dimensional optical waveguide layer, and wherein at least a portion of the light receiving part is embedded in the optical transmission region, whereby the present invention can provide a semiconductor device having reduced direction dependency when light propagating through the optical transmission region is received.

Abstract: A studless tire contains tread portion made of vulcanized rubber, compounded from 100 parts by weight of rubber and 2 to 30 parts by weight of short fibers, and the tread portion has a ground connecting region with sipes, formed by pressing thin plates onto the tread rubber during vulcanizing, whereby the thin plates orient the short fibers in a radial direction. Preferably, the short fibers have a diameter of not more than 30 &mgr;m and a length of from 0.3 to 20 nm, and the thickness of the thin plates or the width of the sipes ranges from 0.2 to 0.5 mm with spacings being sipes less than 10 mm. The short fibers are circumferentially oriented before pressing the thin plates, and the total length in mm of axial component of all sipes ranges from 0.05 to 0.15 times the area in mm2 of ground contacting region.

Abstract: The present invention provides a rubber composition for tire tread having compatibility between low fuel consumption and abrasion resistance, especially abrasion resistance under severe condition. The rubber composition for tire tread is obtained by adding carbon black containing silica as 10 to 55 parts by weight based on a rubber component of 100 parts by weight and silica coupling agent of 2 to 8% by weight based on the carbon black containing silica.

Abstract: There is provided a rubber composition for a tire tread having a remained despersibility of reinforcing agents without increased rubber hardness, an improved performance on snow and ice road, and an improved abrasion resistance, and inhibited from increasing in hardness or inhibited from increasing in hardness with the passage of time. A rubber composition for a tire tread, which comprises (a) a diene rubber, (b) glass fibers, (c) a reinforcing agent, and 1 to 15 parts by weight of (d-1) inorganic powders having a Mohs hardness of less than 6.5 and an average particle-size of less than 25 &mgr;m and/or (d-2) silicone rubber powders based on 100 parts by weight of the diene rubber.

Abstract: An optoelectric integrated device includes a three-dimensional solid semiconductor crystal, such as a silicon ball, and a plurality of optical devices including a light-emitting device and a light-receiving device integrated on the surface of the semiconductor crystal. Light is emitted and received between the light-emitting device and the light-receiving device through the interior of the semiconductor crystal used as an optical wiring medium.

Abstract: Aluminum hydroxide having specific characteristics, and a tire tread rubber composition and a pneumatic tire employing the aluminum hydroxide, which allow grip performance and abrasion resistance to increase and rolling resistance to decrease and are superior in processibility, are provided.

Abstract: A semiconductor laser capable of controlling a polarization mode of output light is disclosed. In a fabrication method of the laser, after two laser portions are independently formed, the laser portions are positioned to be optically coupled to each other. In another fabrication method of the laser, after at least portions of two laser portions are separately formed, an irregularly-formed portion at a boundary portion therebetween is removed. The fabrication method can be facilitated and a degree of freedom in the polarization control can be increased, since the two laser portions are separately formed.

Abstract: A surface light-emitting device includes an active layer and a set of reflectors. The reflectors are arranged on both opposite sides of the active layer such that light can be emitted in a direction perpendicular to the active layer. At least a portion of the reflectors includes a plurality of layers of compound semiconductors at least one of which includes nitrogen. Current is injected into the active layer, and the intensity of the light emitted from the surface light-emitting device is changed by the current modulated in accordance with a signal to be transmitted. At least one of the layers of compound semiconductors may also include aluminum.

Abstract: A fabrication method of a semiconductor laser capable of controlling a polarization mode of output light is disclosed. In the fabrication method, after two laser portions are independently formed, the laser portions are positioned to be optically coupled to each other. In another fabrication method of the laser, after at least portions of two laser portions are separately formed, an irregularly-formed portion at a boundary portion therebetween is removed. The fabrication method can be facilitated and a degree of freedom in the polarization control can be increased, since the two laser portions are separately formed.

Abstract: In an optical device having a diffraction grating and at least two surfaces for reflecting light, the oscillation state is switched between a first oscillation state mainly based on resonance by distributed reflection by the diffraction grating, and a second oscillation state mainly based on Fabry-Perot resonance between the two surfaces. The characteristics of one of two modes to be used are improved at the cost of coherence of the other mode.

Abstract: An optical semiconductor device, such as an optical flter and an oscillation polarization selective semiconductor device for switching oscillation polarization modes between two different polarization modes, includes at least one gain region, at least one lossy region, a first control unit for controlling the gain region to control a gain spectrum of the device, and a second control unit for controlling the lossy region to control a cavity loss spectrum of the device such that a polarization dependency with respect to the two different polarization modes is imparted to the cavity loss spectrum. The gain region includes a light waveguide with an active layer which allows the two different polarization modes. The lossy region includes a light waveguide which allows the two different polarization modes.

Abstract: An improved compound semiconductor device, such as a distributed Bragg reflection type or distributed feedback type laser device, having regions with and regions without a diffraction grating. The device is fabricated without exhibiting surface irregularities by growing a first epitaxial layer on a semiconductor substrate, forming a fine uneven structure on the surface of the first epitaxial layer and growing a second epitaxial layer on the fine uneven structure. The fine uneven structure has a surface shape which exposes crystal orientations that facilitate subsequent epitaxial growth. In one embodiment, portions of the fine uneven structure are formed as a diffraction grating while other portions are formed insufficiently uneven to have a diffraction effect for any usable light wavelength. The fine uneven structure may suitably be shallow, have a short pitch or be provided at a slant to the light propagation direction, in order to preclude a diffraction effect.