Abstract: An optical frequency-division multiplexer includes: a first optical coupler configured to receive a first wavelength-division multiplexed light obtained by wavelength-division multiplexing a first carrier light and a first monitor light and split the first carrier light and the first monitor light from each other; an optical modulator configured to optically modulate the split first carrier light using a signal including a first data signal so as to multiplex the first data signal with the first carrier light; a receiver configured to receive a branched part of the split first monitor light and demodulate a second data signal from the first monitor light; and a second optical coupler configured to couple a remaining part of the split first monitor light and the first carrier light with which the first data signal has been multiplexed.

Abstract: An optical transmission system includes: multiplex transmitting devices, each configured to modulate, with an optical carrier, a data signal modulated into light by an optical modulator in a non-linear optical medium arranged on a transmission path so as to multiplex the data signal into the optical carrier, the data signal having a frequency different in each of the multiplex transmitting devices; a receiving device configured to execute optical-to-electrical conversion on the optical carrier received from the transmission path so as to execute reception process of the data signals multiplexed by the multiplex transmitting devices; and a management device configured to specify a frequency band to be used, based on a modulation band of each of the optical modulators, and manage assignment of the frequency of each of the data signals within the frequency band to be used so as to avoid an effect of harmonics generated upon the optical-to-electrical conversion.

Abstract: A probe light source produces probe light having a second wavelength different from a first wavelength of signal light. To a light modulator, the probe light and signal light produced from the probe light source are supplied. The light modulator multiplexes the probe light and signal light produced from the probe light source, and supplies it to a nonlinear optical medium. Further, the light modulator modulates the probe light by an intensity change of the signal light in the nonlinear optical medium, and outputs modulated light having the second wavelength based on the data of the signal light.

Abstract: A waveform shaping apparatus includes a quantum dot optical amplifier in which an amplification factor of input signal beams saturates if the optical power of the signal beams is equal to or greater than a predetermined value; and a quantum dot saturable absorber in which an absorption factor of the input signal beams saturates if the optical power of the signal beams is under a predetermined value. The quantum dot optical amplifier and the quantum dot saturable absorber are connected in series with a transmission path of the signal beams, and shape the waveform of the signal beams. Voltages applied to the quantum dot optical amplifier and the quantum dot saturable absorber, respectively, are adjusted based on the optical power of the signal beams.

Abstract: An optical apparatus includes a dispersing medium configured to receive carrier light which has been subjected to phase modulation in accordance with subcarrier modulation signals which has been modulated using data signals, and a signal extractor configured to extract the data signals from light output from the dispersing medium.

Abstract: There is provided an optical multiplexing apparatus including an extraction unit configured to extract a pilot signal multiplexed on light propagated on a transmission line, a generator configured to generate an optical subcarrier modulated signal based on a data signal to be transmitted on the transmission line and the pilot signal extracted by the extraction unit, a multiplexer configured to multiplex the optical subcarrier modulated signal generated by the generator with carrier light in order to multiplex the data signal on the carrier light propagated on the transmission line, and a nonlinear optical medium which is provided on the transmission line and on which the carrier light multiplexed by the multiplexer is incident.

Abstract: An optical pulse generating device includes a continuous light input unit to which continuous light is input; a pulse input unit to which control pulse light that includes periodic pulses of light is input; and a generating unit that generates pulse light from the continuous light by clipping the continuous light according to a variation of emission intensity of the control pulse light.

Abstract: An optical-signal processing apparatus includes a polarizer that is provided at an output terminal of an optical fiber, and polarization control units that adjust a first excitation light and a second excitation light input to the optical fiber. The polarization control units adjust polarization states of the first excitation light and the second excitation light so that, when the first excitation light and the second excitation light are input to the polarizer, polarization directions of the first excitation light and the second excitation light are orthogonal to each other, and angular difference between the polarization direction of the first excitation light and the polarization direction of the second excitation light, measured against the polarization main axis of the polarizer, is equal to or smaller than a threshold value.

Abstract: A photosensitive resin composition comprising: a vinyl-based polymer (I) obtained by polymerizing a monomer mixture containing a monomer (a) having a phenolic hydroxyl group; a vinyl-based polymer (II) obtained by polymerizing a monomer mixture containing a carboxyl group-containing vinyl monomer (b), and having a weight average molecular weight of 20,000 to 100,000, provided that the vinyl-based polymer (I) is excluded; a quinonediazide compound (III); and a compound (IV) represented by following formula (5). [In the formula, Y is a hydrocarbon group of 1 to 6 carbon atoms; 1 and m are each independently an integer of 1 to 3; n is 1 or 2; p and q are each independently 0 or 1.

Abstract: The present invention is related to a photosensitive resin composition containing: a vinyl-based copolymer (I) obtained by polymerizing a monomer mixture containing a monomer (a) having a phenolic hydroxyl group and a carboxyl group-containing vinyl monomer (b); a quinonediazide compound (II) and a compound (III) represented by the following formula (5), and to a photosensitive dry film and a method for forming a patter by using the photosensitive resin composition.

Abstract: In an optical signal processing apparatus, carrier light propagates through a nonlinear optical medium. An optical combiner optically combines output control light for generating idler light of the carrier light with the carrier light. An optical splitter splits the idler light from the carrier light. A receiver acquires a signal multiplexed on the carrier light from the idler light split by the optical splitter.

Abstract: The polarization direction of an optical signal is changed by a polarization controller so as to be orthogonal to a main axis of a polarizer. A control pulse generator generates control pulses from control beam with a wavelength which is different from the wavelength of the optical signal. The optical signal and the control pulse are input to a nonlinear optical fiber. In the nonlinear optical fiber, the optical signal, during a time period in which the optical signal and the control pulse coincide, is amplified with optical parametric amplification around a polarization direction of the control pulse. The optical signal, during the time period in which the optical signal and the control pulse coincide, passes through the polarizer.

Abstract: A method is for calculating an optical noise index of a signal light extraction apparatus that extracts signal light in a polarization plane by inputting signal light and a sampling pulse, different from the signal light in polarization plane by a given angle, to a nonlinear optical medium, and by passing light output from the nonlinear optical medium through an orthogonal polarizer having a polarization plane orthogonal to that of the signal light. The method includes calculating an output optical noise of the signal light extraction apparatus using a parametric gain of the nonlinear optical medium, a power of a quantum noise of the light having passed through the orthogonal polarizer, and a ratio of a power of the signal light and a power of the signal light sampled by the sampling pulse; and calculating an optical noise index using the output optical noise.

Abstract: According to an aspect of an embodiment, an apparatus for controlling optical waveform, comprises: an input port for inputting a signal light having a modulating frequency and a signal light power; a pump light generator generating pulsed pump light having a frequency higher than the modulating frequency of the signal light and a pulsed pump light power; a nonlinear optical medium for transmitting the signal light from the input port and the pulsed pump light, the nonlinear optical medium having a gain of the signal light based on a nonlinear optical effect; and a power adjustor for adjusting a gain of the signal light saturates in the nonlinear optical medium by a nonlinear optical effect by adjusting at least one of the signal light power or the pulsed pump light power.

Abstract: Signal light, pumping light and control light having different wavelengths are input to a nonlinear optical medium. The power of the pumping light is controlled to generate a desired gain in the nonlinear optical medium. The power of the control light is controlled to saturate the gain of the nonlinear optical medium.

Abstract: An optical signal processing apparatus includes an input unit to which signal light is input; a wave coupling unit that couples the signal light from the input unit and pump light having a waveform different from that of the signal light; a first nonlinear optical medium that transmits light coupled by the wave coupling unit, the light being the signal light and the pump light; a dispersion medium that transmits the light that has been transmitted through the first nonlinear optical medium; and a second nonlinear optical medium that transmits the light that has been transmitted through the dispersion medium.

Abstract: An optical modulator combines and inputs a signal light propagating through the optical network and a control light having information concerning the optical network to a nonlinear optical medium. The optical modulator modulates the signal light according to changes in intensity of the control light, in the nonlinear optical medium.

Abstract: An optical signal processing device includes a waveform width widening unit configured to widen a waveform width of an optical signal; and an optical limiter circuit, to which the optical signal the waveform width of which is widened is input, configured to suppress an intensity of the optical signal in a region where an input intensity and an output intensity are not proportional.

Abstract: An O/E conversion element converts an input NRZ optical signal into an electric signal. A clock recovery circuit recovers a clock signal from the electric signal obtained by the O/E conversion element. A phase modulator applies phase modulation to the NRZ optical signal, using the recovered clock signal. An intensity modulator applies intensity modulation to the NRZ optical signal, using the recovered clock signal. A dispersion medium compensates for a frequency chirp of an optical signal output from the intensity modulator.

Abstract: In an optical network system a carrier light propagates along a transmission line. A control light generator included in an optical multiplexing apparatus generates a control light obtained by modulating an intensity-modulated light by a data signal. A multiplexer combines the control light with the carrier light for modulating the carrier light in a nonlinear optical medium in the transmission line by the control light. The carrier light which propagates along the transmission line is modulated in the nonlinear optical medium on the basis of the control light.