| Patent application number | Description | Published |
|---|
| 20080285303 | OPTICAL MODULE AND MANUFACTURING METHOD THEREOF - An optical module according to the present invention comprises an electric wiring substrate, a first optical element mounted on the electric wiring substrate so that a heat generation section of the first optical element is positioned relatively close to a substrate surface of the electric wiring substrate and a heat sink mounted on the same plane as the mounting plane of the first optical element on the electric wiring substrate, the heat sink being mounted on the electric wiring substrate so that an area of electric wiring on the electric wiring substrate overlaps the heat sink. This improves the efficiency of heat radiation of the optical module. | 11-20-2008 |
| 20090245798 | OPTICAL CIRCUIT AND RECEIVER CIRCUIT - An optical circuit that converts a phase-modulated optical signal into intensity-modulated signal light in accordance with a phase, the optical circuit including a square mode distribution forming portion that forms a plurality of interfering signals each assuming a square mode shape, the interfering signals having respective phases shifted from each other by a certain angle, a light interference portion that creates a signal having a certain mode distribution, from the interfering signal, and that applies a Fourier transform to the signal having the certain mode distribution, and an output portion that has a plurality of waveguides each provided in correspondence with the phase and that outputs an optical signal that has been output from the light interference portion. | 10-01-2009 |
| 20090252505 | PHASE-MODULATED SIGNAL RECEIVING DEVICE - A monitor circuit detects the average light receiving current of a photoelectric conversion device for receiving a positive-phase intensity-modulated signal and outputs the detected current value to a control unit. The control unit adjusts the heater current of a phase adjustment heater in such a way as to maximize or minimize the output of the monitor circuit and controls the amount of delay of the phase reference light of a demodulator. | 10-08-2009 |
| 20100074570 | OPTICAL CIRCUIT - According to an aspect of an embodiment, an optical circuit comprising: at least two pairs of two input waveguides; a slab waveguide with one end coupled to two pairs or more of the two input waveguides; and four output waveguides coupled to another end of the slab waveguide; wherein a distance between two pairs of adjacent two input waveguides among two pairs or more of the two input waveguides is approximately four times as long as a distance between the two input waveguides. | 03-25-2010 |
| 20100085630 | DEMODULATOR - A demodulator and method are provided. The demodulator for demodulating an optical signal, includes a splitter that splits a differential phase modulation signal into a first split light component and a second split light component, couples the first split light component to a first optical path and the second split light component to a second optical path, a first medium disposed on the first optical path, a second medium disposed on the second optical path and having a refractive index different from that of the first medium, and a combiner that combines the first split light component that has passed through the first medium and the second split light component that has passed through the second medium, wherein one of the first split light component and the second split light component is delayed in relation to the other. | 04-08-2010 |
| 20100119230 | OPTICAL RECEIVING CIRCUIT - An optical receiving circuit receives and demodulates an optical signal subjected to phase modulation and wavelength division multiplexing. The optical receiving circuit includes an interfering unit that causes a reference signal to interfere with the optical signal to output resulting signals as positive-phase signals and negative-phase signals; and a wavelength separator having input ports receiving the positive-phase signals and the negative-phase signals, the positive-phase and negative-phase signals being adjacent to each other. The wavelength separator separates according to wavelength, the positive-phase signals and the negative-phase signals, and from output ports, outputs for each wavelength, a separated positive-phase signal and negative-phase signal in a state of being adjacent to each other. The optical receiving circuit further includes balanced receivers respectively provided for each wavelength, where a given balanced receiver for a given wavelength performs balanced reception and demodulation of the separated positive-phase signal and negative phase signal of the given wavelength. | 05-13-2010 |
| 20100129089 | DEMODULATOR AND RECEIVING DEVICE - A demodulator includes: a splitter that branches a differential phase shift keying optical signal into a first branched optical signal passing through a first optical path and a second branched optical signal passing through a second optical path; a multiplexer that multiplexes the first branched optical signal having passed through the first optical path and the second branched optical signal having passed through the second optical path and makes interference between the first branched optical signal and the second branched optical signal; and a double refraction medium that reduces difference between phase differences between each polarized wave between the first branched optical signal and the second branched optical signal multiplexed by the multiplexer. | 05-27-2010 |
| 20110262149 | LIGHT RECEPTION DEVICE AND METHOD FOR CONTROLLING THE SAME - A light reception device includes: an interferometer that outputs a signal obtained by making an optical phase modulated signal interfere with a reference signal after shifting an optical phase of the optical phase modulated signal by a given amount; a light reception element that receives an output signal from the interferometer and converts the output signal into a light reception current; and a phase controller that controls a control amount in controlling the given amount so that a value of a function, which is calculated based on an amount relating to the light reception current and a change amount of an amount relating to the light reception current against the control amount, becomes an extreme value or 0. | 10-27-2011 |
