Abstract: A fiber with which a further enhanced electric field intensity is obtained when a compressive force is applied across the longitudinal axis of the fiber. The fiber is composed of a potential generating filament having at least one interior angle of less than 120° in a contour shape in a sectional view in a direction perpendicular to a longitudinal axis of the fiber.

Abstract: An example objective of the present invention is to provide a method for detecting a tyrosine residue in a sample and a compound that can be used in the method. One aspect of the present embodiment relates to a method for detecting a tyrosine residue in a sample, wherein fluorescence emission from a reaction product of a terbium compound represented by the predetermined formula and a tyrosine residue is detected.

Abstract: A wireless power feeding system capable of long distance and highly efficient space transmission of power is provided. A wireless power feeding system includes a power transmitter, a power receiver, and a power receiving body. The power transmitter generates electromagnetic waves. The power receiver is supplied with power by means of the electromagnetic waves received from the power transmitter using a magnetic field resonance phenomenon. The power receiving body is inserted into an electromagnetic field created by the power transmitter and the power receiver, and receives power by means of the electromagnetic field.

Abstract: A wireless power feeding system capable of long distance and highly efficient space transmission of power is provided. A wireless power feeding system includes a power transmitter, a power receiver, and a power receiving body. The power transmitter generates electromagnetic waves. The power receiver is supplied with power by means of the electromagnetic waves received from the power transmitter using a magnetic field resonance phenomenon. The power receiving body is inserted into an electromagnetic field created by the power transmitter and the power receiver, and receives power by means of the electromagnetic field.

Abstract: The present invention provides a surface-emission type semiconductor laser wherein an effective length of a cavity is reduced, thereby enabling to realize a higher-speed direct modulation. In the surface-emission type semiconductor laser according to the present invention, when supposing the optical path length (L) of a resonator part relative to a lasing wavelength ?0 to be given as 0.9×?0?L?1.1×?0, and denoting the refractive indexes of a high refractive index layer and a low refractive index layer of a dielectric DBR by nH1 and nL1; the average refractive index within an optical path length ?0/4 in the semiconductor in contact with the dielectric DBR by nS1; and the refractive indexes of the high refractive index layer and the low refractive index layer of a semiconductor DBR by nH2 and nL2, respective materials to be used are selected so as to satisfy the following conditions (1) and (2): nH1>f(nS1)nL12+g(nS1)nL1+h(nS1),??(1) where f(nS1)=0.0266 nS12?0.2407 nS1+0.6347; g(nS1)=?0.0508 nS12+0.

Abstract: An optical communication system for performing data transmission with optical signals comprises a first optical transmitter and a first optical receiver. The first optical transmitter has a first surface-emitting laser including an active layer of a multiple quantum well structure having a quantum well layer of InxGa1-xAs (0.15?x?0.35), the first surface-emitting laser having an oscillation wavelength ranging from 1000 nm to 1100 nm inclusive. The first optical transmitter transmits an optical signal generated by the first surface-emitting laser. The first optical receiver is connected to the first optical transmitter by a first optical transfer path, and receives the optical signal transmitted from the first optical transmitter through the first optical transfer path.

Abstract: A surface emitting laser is provided with a first multilayer Bragg reflecting mirror including a first layer, a second multilayer Bragg reflecting mirror including a second layer, and an optical resonator unit that is held between these multilayer Bragg reflecting mirrors and includes an active layer. Further, the optical resonator unit contacts with the first layer and second layer respectively. The effective refraction index neff of the resonator unit is larger than either the first layer or the second layer, and an optical length neffL of the optical resonator unit has a relationship with an oscillating wavelength ? of the surface emitting laser to satisfy the following relationship: 0.5?<neffL?0.7?.

Abstract: The present invention provides a surface-emission type semiconductor laser wherein an effective length of a cavity is reduced, thereby enabling to realize a higher-speed direct modulation. In the surface-emission type semiconductor laser according to the present invention, when supposing the optical path length (L) of a resonator part relative to a lasing wavelength ?0 to be given as 0.9×?0?L?1.1×?0, and denoting the refractive indexes of a high refractive index layer and a low refractive index layer of a dielectric DBR by nH1 and nL1; the average refractive index within an optical path length ?0/4 in the semiconductor in contact with the dielectric DBR by nS1; and the refractive indexes of the high refractive index layer and the low refractive index layer of a semiconductor DBR by nH2 and nL2, respective materials to be used are selected so as to satisfy the following conditions (1) and (2): nH1>f(nS1)nL12+g(nS1)nL1+h(nS1),??(1) where f(nS1)=0.0266 nS12?0.2407 nS1+0.6347; g(nS1)=?0.0508 nS12+0.

Abstract: A surface emitting laser is provided with a first multilayer Bragg reflecting mirror including a first layer, a second multilayer Bragg reflecting mirror including a second layer, and an optical resonator unit that is held between these multilayer Bragg reflecting mirrors and includes an active layer. Further, the optical resonator unit contacts with the first layer and second layer respectively. The effective refraction index neff of the resonator unit is larger than either the first layer or the second layer, and an optical length neffL of the optical resonator unit has a relationship with an oscillating wavelength ? of the surface emitting laser to satisfy the following relationship: 0.5?<neffL?0.7?.

Abstract: A surface emitting laser including a semiconductor substrate, a semiconductor substrate, a first reflector formed on the semiconductor substrate, an active layer formed on the first reflector, a tunnel junction layer formed above a part of the active layer, a semiconductor spacer layer which covers the tunnel junction layer, a second reflector formed on the semiconductor spacer layer in a region above the tunnel junction layer, a first electrode formed in the periphery of the second reflector on the semiconductor spacer layer, and a second electrode electrically connected to a layer lower than the active layer, wherein a layer thickness of the semiconductor spacer layer in the region directly above the tunnel junction layer is thinner than the layer thickness of the semiconductor spacer layer in the region directly below the first electrode.

Abstract: An optical communication system for performing data transmission with optical signals comprises a first optical transmitter and a first optical receiver. The first optical transmitter has a first surface-emitting laser including an active layer of a multiple quantum well structure having a quantum well layer of InxGa1-xAs (0.15?x?0.35), the first surface-emitting laser having an oscillation wavelength ranging from 1000 nm to 1100 nm inclusive. The first optical transmitter transmits an optical signal generated by the first surface-emitting laser. The first optical receiver is connected to the first optical transmitter by a first optical transfer path, and receives the optical signal transmitted from the first optical transmitter through the first optical transfer path.

Abstract: A vehicle-mounted optical communication system, which uses an optical signal to perform data transmission, comprises a first optical transmitter and an optical receiver. The first optical transmitter, which is mounted on a vehicle, has a multiple quantum well structure, in which an active layer has a quantum well layer of InxGa1-xAs (where 0.15?x?0.35), and includes a first surface emitting laser the oscillation wavelength of which is between 1000 nm and 1100 nm inclusive. The first optical transmitter transmits an optical signal generated by the first surface emitting laser. The optical receiver, which is mounted on the vehicle and connected to the first optical transmitter via a first optical transmission path, receives the optical signal, which was transmitted by the first optical transmitter, via the first optical transmission path.

Abstract: In an avalanche photodiode having a separated electron injection type light absorbing layer/multiplication layer structure, the multiplication layer comprises In(1−x−y)AlxGayAs with the composition thereof being graded from InAlAs on the light absorbing layer side to InGaAs and preferably has a thickness of not more than 0.1 &mgr;m. By virtue of the above construction, very low noise characteristics and ultraspeed characteristics can be attained in photodetectors at 1 &mgr;m wavelength for long distance optional communications.

Abstract: A semiconductor photonic element is provided, which realize low threshold current and satisfactory characteristics in the high temperatures and/or high output operating condition.

Abstract: The invention provides a semiconductor optical modulation device which has low power dissipation, high extinction ratio and high speed response features. An n-type InP clad layer, an n.sup.- -type InAlAs-InAlGaAs composition inclination multiple layer, a p-type InP clad layer and a p.sup.+ -type InGaAs contact layer are layered on an n-type InP substrate. The layers are etched up to an intermediate location of the n-type clad layer to form a rib waveguide, and a positive electrode is formed on an upper portion of the rib waveguide. Further, a negative electrode is formed on the substrate.

Abstract: An avalanche photodiode is provided which consists of a staircase APD with a periodic multilayer structure graded in composition from InAlAs to InGa.sub.x Al.sub.(1-x) As (x>0.1) as the multiplication layer to improve the dark current characteristic. Another photodiode with separate photoabsorption and multiplication regions is provided with an electric-field relaxation layer whose bandgap is wider than that of the photoabsorption and has a triple structure with a highly-doped layer sandwiched between lightly-doped layers. This photodiode incorporates in detail on an n-type InP substrate, an avalanche multiplication layer 13 of a periodic multilayer structure graded in composition from n.sup.- -InAlAs to InGa.sub.x Al.sub.(1-x) As, a p.sup.- -InGaAs photoabsorption layer 17, and an InP electric-field relaxation triple layer 16 consisting of n.sup.-, p.sup.+, and p.sup.- layers between the avalanche multiplication layer 13 and the photoabsorption layer 17.

Abstract: On a p-type InP substrate 12, there are provided a p-type InGaAs light absorptive layer 14 and an InAlAs/InGaAs superlattice avalanche multiplier layer 15. By selecting the composition of the well layer and the barrier layer of the avalanche multiplier layer 15, a strain is applied to at least one of them so that the difference .DELTA. Ec between the energies at the lower end of the conduction band of the well layer and/or the barrier layer is increased, or the difference .DELTA. Ev between the energies at the upper end of the valence band of the well layer and/or the barrier layer is decreased, and/or the effective mass of the hole within the well layer and/or barrier layer is decreased. Thus, the ionization factor ratio is further improved, or the pile-up of the hole is alleviated, or the traveling time of the hole is shortened to achieve an avalanche multiplier semiconductor photodetector having a wide bandwidth, low noise and high response characteristic.

Abstract: An avalanche photodiode includes an avalanche multiplication layer of a hetero-periodical structure consisting of alternately provided barrier and well layers. Each barrier layer includes a multi-quantum barrier layer consisting of alternately provided short-width barrier and well layers. The barrier and well layers include respectively first and second III-group elements which meet the following conditions:E.sub.A <E.sub.B, and E.sub.A +E.sub.gA <E.sub.B +E.sub.gBorE.sub.A <E.sub.B, and E.sub.A +E.sub.gA >E.sub.B +E.sub.gBwhere E.sub.A and E.sub.B are average ionization energies of the first and second III-group elements respectively, and E.sub.gA and E.sub.gB are forbidden band gap energies, respectively.

Abstract: A dibenz[b,e]oxepin derivative represented by the formula (I) ##STR1## wherein R.sup.1 and R.sup.2 are each hydrogen, halogen, lower alkyl or alkoxy; one of R.sup.3 and R.sup.4 is lower alkoxy, and other is a group represented by the formula (II) ##STR2## wherein R.sup.5 is hydrogen or lower alkyl, A is hydroxyl, --O(CH.sub.2).sub.m --R.sup.6 (wherein m is an integer of 1-6, R.sup.6 is hydrogen, lower alkyl or alkoxy, cycloamino, or lower alkoxycarbonyl), cycloamino, di-lower alkylamino or --NH(CH.sub.2).sub.n --R.sup.7 (wherein n is an integer of 0-3, R.sup.7 is hydrogen, hydroxyl, phenyl, thiazole or cycloamino).

Abstract: A novel 3-aroyl-6,7-dihydro-5H-pyrrolo[1,2-c]imidazole-7-carboxylic acid derivative which is useful as a medicine having excellent analgesic and anti-inflammatory actions with remarkably less toxicity and side-effects.