Abstract: An optical TDM multiplexing apparatus to multiplex a plurality of input signals in the optical stage in the time domain according to the invention comprise a plurality of signal light sources to generate optical signals each having a wavelength different from the others to carry each of the plurality of the input signals, a timing adjuster to adjust timings between the respective optical signals so that each optical signal output from the plurality of the signal light sources is disposed on a time slot different from the others in the time domain, an optical multiplexer to multiplex each optical signal output from the timing adjuster in the wavelength domain and a wavelength converter to convert each wavelength of the output light from the optical multiplexer into a predetermined wavelength.

Abstract: An optical transmitter outputs WDM signal lights comprising signal lights with 100 wavelengths of 10 Gbit/s, onto an optical transmission fiber. In the optical transmission line, a transmission fiber and a local area dispersion compensation fiber are disposed per repeater span defined by an optical amplification repeater, the local area dispersion compensation fiber is for compensating the average chromatic dispersion in the repeater span to become 2 ps/nm/km as well as a dispersion slope to become zero, and a wide area dispersion compensation fiber for compensating the average chromatic dispersion to become −0.2 ps/nm/km as well as the dispersion slope to become zero is disposed per predetermined number of optical repeater spans. The optical transmission fiber comprises a single mode optical fiber with large core diameter having a zero dispersion wavelength at a 1.3 &mgr;m band and plus chromatic dispersion at a signal wavelength band (a 1.55 &mgr;m band).

Abstract: To increase thermal efficiency by increasing the degree of constant volume of a fuel-air mixture at the time of combustion in an internal combustion engine. In an internal combustion engine, a piston slidably fitted in a cylinder is connected to a crankshaft via a connecting rod, and a cylinder head in which a combustion chamber is defined is disposed between the piston and the crankshaft. As compared with a background art internal combustion engine in which a combustion chamber is disposed opposite to a crankshaft with a piston located therebetween, a ratio of an increased amount of the volume of the combustion chamber to an increased amount of a crank angle of the piston from the top dead center position can be suppressed at a small value.

Abstract: An optical fiber transmission line for realizing satisfactory long haul transmission characteristics using two kinds of optical fibers. The optical fiber transmission line includes a plurality of local dispersion compensating spans, wide dispersion compensating spans disposed at predetermined intervals, and optical repeating amplifiers to connect each span. The local dispersion compensating span includes a first optical fiber with positive dispersion having an effective core area of 130 &mgr;m2 or more and a second optical fiber with a negative dispersion value of −50 ps/nm/km or less to transmit the light output from the first optical fiber. The wide dispersion compensating span consists of a third optical fiber having the same configuration and composition with the first optical fiber.

Abstract: An optical fiber (12a) with a large effective core area and a large chromatic dispersion value is disposed on an input side of signal light, and an optical fiber (12b) with a small effective core area and a small chromatic dispersion value or a chromatic dispersion value of negative polarity is disposed on an output side of the signal light. A pumping light source (14) generates pumping light of 1450 nm to cause Raman amplification of 1550 nm in the optical fiber (12b). The output light from the pumping light source (14) enters the optical fiber (12b) from the back through a WDM optical coupler (16). Provided that y=(Pin−&agr;)/(Pp·10 Log L) where input power of the optical fiber (12a) (i.e.

Abstract: An object of this invention is to improve transmission characteristics in WDM transmission. An optical transmitter (10) wavelength-multiplexes signal lights of wavelengths &lgr;1 through &lgr;n and outputs them onto an optical transmission line (12). Optical powers of the signal lights of the respective wavelength &lgr;1 through &lgr;n are identical or become smaller proportional to the wavelength. One repeater span of the optical transmission line (12) is composed of an optical fibers (20, 22) and an optical amplifier (24), and a gain equalizer (26) is dispersed every several repeater spans. The optical amplifier (24) in the repeater span amplifies each signal light so that optical power of a signal on the shorter wavelength side becomes smaller than that of a signal on the longer wavelength side. The gain equalizer (26) equalizes optical powers of the respective signal lights.

Abstract: An object of the present invention is to realize almost the same transmission characteristic in all wavelengths at a transmission rate of 10 Gb/s or more. An optical transmitter 10 outputs WDM signal light multiplexed with signal light of a plurality of wavelengths toward an optical transmission line 12. The optical transmission line 12 comprises an optical transmission fiber 14, an optical repeating amplifier 16 and a dispersion compensating fiber 18. The gain characteristic of the optical repeating amplifier 16 is set so that the gain becomes the maximum at the effective zero dispersion wavelength of the optical transmission line 12 and that lowers inversely proportional to the distance from the effective zero dispersion wavelength. The whole optical transmission line 12 is set so that the peak power deviation between the effective zero dispersion wavelength &lgr;0 and the wavelength &lgr;1 or &lgr;n on both end becomes approximately 4 dB.

Abstract: An object of the present invention is to prevent an increase of the degree of polarization of an output pumping light even if one of pumping light sources has a failure. Laser diodes (30a, 30b) are composed of FP-LDs made of InGaAsP to laser-oscillate at 1480 nm band. The outputs from the laser diodes (30a, 30b) enter a polarizing beam splitter (32) in orthogonal state of polarization and are combined there. The combined light by the polarizing beam splitter (32) enters a depolarizing element (34) and is depolarized there.

Abstract: An optical clock multiplier comprises a phase modulator (12) to shift a phase in pulse duration of an input optical clock pulse by &pgr;, a polarization mode dispersion device (16) having a predetermined time difference between first and second polarizations orthogonal to each other to divide an output light from the phase modulator into the first and second polarization components, and a polarization device (20) to extract one of polarization components in a third polarization practically inclined at an angle of 45° against the first polarization and a fourth polarization orthogonal to the third polarization out of the output light from the polarization mode dispersion device.

Abstract: A bridge tap branches from a two-wire transmission line for communications and is connected to a terminal-function assisted noise filter which is then connected at the downstream end with a telephone. The terminal-function assisted noise filter comprises a terminal circuit (an impedance matching circuit with four ports) and a noise removing circuit. The terminal circuit consists mainly of two resistors connected in series with the bridge tap and a capacitor connected in parallel with the same. Accordingly, the impedance matching circuit and the noise filter equipped with the impedance matching circuit can be implemented where the communicating action of a data communication device over the main line is protected from being interfered by reflection waves derived from the bridge tap.

Abstract: A method of electroless plating for processing a plating surface to form a barrier layer being capable of uniformly forming a barrier layer and reducing the consumption of a processing solution, comprising a step of feeding a processing solution used in at least one of the pre-processing steps of the electroless plating and the electroless plating step to the plating surface for puddling treatment, or, using a processing solution at least containing, with respect to one mole of a first metallic material supplying a main ingredient of the barrier layer, three or more moles of a completing agent and three or more moles of reducing agent and having a pH value adjusted to 9 or more and stored in an atmosphere of an inert gas or ammonia gas, and a corresponding electroless plating apparatus.

Abstract: To realize an optical demultiplexer with a constant chromatic dispersion value, an optical signal of wavelength (&lgr;1) enters a port (A) of an optical circulator (10), and an optical signal of wavelength (&lgr;2) enters a port (A) of an optical circulator (12). A port (B) of the optical circulator (10) connects to a port (X0) of an interleaved optical filter (14), and a port (B) of the optical circulator (12) connects to a port (X1) of the optical filter (14). A port (Y0) of the optical filter (14) connects to a port (Y1) of the optical filter (14) through an optical isolator (16). The optical isolator (16) allows the optical propagation from the port (Y0) to the port (Y1) of the optical filter (14) and refuses the optical propagation from the port (Y1) to the port (Y0). An optical coupler (18) combines the input lights of the input ports (X0 and X1) from ports (C) of the optical circulators (10 and 12) and outputs from the output port (Y0).

Abstract: In an engine for a motor vehicle, an upward offset of a transmission input shaft is sufficiently increased without being obstructed by a cylinder block. This shortens the overall length of the engine in the longitudinal direction of the motorcycle. The engine for a motor vehicle has a cylinder block extending upwardly and forwardly of the motor vehicle from an upper portion of the front end of a crankcase. A transmission input shaft is offset upwardly with respect to a plane, which includes the axes of a crankshaft and a transmission output shaft. The cylinder block is disposed to have an axis passing forwardly of the axis of the crankshaft. With this construction, it is possible to sufficiently increase an upward offset of the transmission input shaft without being obstructed by the cylinder block.

Abstract: A data/audio multiplex transmission system comprising an audio modulator to modulate an input audio signal and output the modulated audio signal, an optical pulse signal generator to generate an optical pulse signal for carrying a LAN data, amplitude of the optical pulse signal being modulated by the modulated audio signal, according to the LAN data and the modulated audio signal, an optical fiber to propagate the optical signal output from the optical pulse signal generator, an opto-electric converter to convert the optical signal propagated on the optical fiber into an electric signal, a filter to extract a predetermined band out of the output signal from the opto-electric converter, an audio demodulator to demodulate the audio signal out of the output from the filter, and a data transmitter to transmit the LAN data included in the output signal from the opto-electric converter for a LAN.

Abstract: The optical amplifier according to the present invention is constructed such that the amount of the electric current fed to the power feeding line 2a is first detected by the current detection means, and then a setting signal is generated to each of the bypass circuits 22 and 23 in accordance with the thus detected amount of the fed current, and thereafter the output level of each of the optical repeater circuits 11 and 12 is controlled respectively by the bypass circuits 22 and 23, so that the output level of these repeater circuits 11 and 12 can be controlled in accordance with the amount of the current fed to the power feeding line 2a.

Abstract: To realize a highly reliable monitor control signal network at low costs, a data transmission system comprises a first network to optically transmit a data signal and a monitor control signal, first and second nodes connecting to the first network, and a second network capable of transmitting the monitor control signal.

Abstract: The optical amplifier according to the present invention is constructed such that the amount of the electric current fed to the power feeding line 2a is first detected by the current detection means, and then a setting signal is generated to each of the bypass circuits 22 and 23 in accordance with the thus detected amount of the fed current, and thereafter the output level of each of the optical repeater circuits 11 and 12 is controlled respectively by the bypass circuits 22 and 23, so that the output level of these repeater circuits 11 and 12 can be controlled in accordance with the amount of the current fed to the power feeding line 2a.

Abstract: A highly efficient mixed flow pump can prevent flow separation which is likely to occur in a corner portion of a flow passage of a diffuser section. The mixed flow pump includes a casing having an axis and defining an impeller section and a diffuser section disposed downstream of the impeller section with stationary diffuser blades protruding from a hub. The diffuser blades are formed so that an angular difference, between a hub blade angle and a casing blade angle, is chosen to conform to a specific distribution pattern along a flow passage of the diffuser section.

Abstract: A dispersion compensating optical transmission line comprises a plurality of optical transmission fibers for transmitting signal light, at least one first dispersion compensator disposed at a first dispersion compensating cycle for compensating an accumulated chromatic dispersion of the signal light so that an average chromatic dispersion is equal to a first desired value, and a plurality of second dispersion compensators disposed at a second dispersion compensating cycle shorter than the first dispersion compensating cycle for compensating the accumulated chromatic dispersion of the signal light so that an average chromatic dispersion is equal to a second desired value which absolute value is larger than that of the first desired value.

Abstract: An optical transmission system comprises a light source to output an optical carrier having a predetermined wavelength, a photoelectric converter, an optical transmission line, an optical circulator to apply an output light from the light source to one end of the optical transmission line and to apply a light through the same end of the optical transmission line to the photoelectric converter, and an optical modulator disposed on the other end of the optical transmission line to return a portion of the light from the optical transmission line as a reference light to the optical transmission line without modulation and to modulate another portion of the light from the optical transmission line with a transmission signal to return it to the optical transmission line as a modulated light.