Abstract: To suppress peeling-off or cracks of a solder-fixing portion, which are caused by vibration during transportation or operation, in an optical modulator with FPC, thereby suppressing deterioration of radio-frequency characteristics of a signal path in an effective manner at low cost. An optical modulator 100 includes a flexible printed circuit (106) that performs electrical connection with a circuit substrate. The flexible printed circuit has a substantially quadrilateral shape. In the flexible printed circuit, a pad (210 and the like), which is electrically connected to the circuit substrate, is provided along one side of the substantial quadrilateral. In addition, in the flexible printed circuit, signal patterns (220 and the like), which are connected to signal lead pins (120 and the like) for signal transmission which is provided in the optical modulator, are provided in another side opposite to the one side.

Abstract: An optical modulation element configured by forming an optical waveguide on an optical element substrate and a polarization-combining part that combines light waves modulated in the optical modulation element are disposed in a housing. A plurality of lead pins are fixed to a side wall of the housing. Each of the plurality of lead pins has a protrusion portion protruding into an internal space of the housing and is electrically connected to the optical modulation element by bonding a wire to the protrusion portion. A loop shape of a wire that is bonded and connected to at least part of the lead pins among the plurality of lead pins is different from a loop shape of a wire that is bonded and connected to other lead pins.

Abstract: Provided is an optical modulator in which low-voltage drive and a stable modulation characteristic are secured over a wide bandwidth.

Abstract: An optical modulator including a flexible printed circuit performing an electrical connection with an external circuit substrate, in which the flexible printed circuit includes a plurality of first pads and the like provided on one surface of the flexible printed circuit along one side of the flexible printed circuit, a plurality of second pads and the like provided on the other surface of the flexible printed circuit at locations that respectively correspond to the plurality of first pads, and a plurality of metal films and the like provided at locations that respectively correspond to the first pads on a side surface of the flexible printed circuit along the one side of the flexible printed circuit.

Abstract: Provided is an optical-waveguide-element module in which a common connecting substrate is used for different optical waveguide elements and deterioration of the propagation characteristics of electrical signals in a curved section of a signal electrode is suppressed.

Abstract: Provided is an optical modulator in which degradation of an extinction ratio is suppressed and a temperature drift phenomenon is suppressed. An optical modulator includes: a substrate having an electro-optic effect; an optical waveguide formed on the substrate; and a control electrode for controlling light waves propagating through the optical waveguide, in which the optical waveguide has one or more Mach-Zehnder type optical waveguides (A1 to A3 and B1 to B3), the control electrode has DC electrodes (C1 to C4) which apply DC bias, a feeder electrode which feeds DC bias to the DC electrode crosses one of two branched waveguides of the Mach-Zehnder type optical waveguide, and a first dummy electrode (a dotted line E5 or E6) is provided at a specific position on the other one of the two branched waveguides, which is a specific position symmetrical in relation to a position at which the feeder electrode crosses the one of the two branched waveguides.

Abstract: A waveguide optical element which includes a plurality of optical waveguides provided on a substrate having an electro-optic effect includes: a plurality of signal electrodes controlling light waves propagating through the optical waveguides; and a plurality of ground electrodes provided so as to interpose each of the signal electrodes therebetween, in which at least one of the ground electrodes includes a first layer and a second layer formed on the first layer, the second layer is formed such that a distance between the second layer and the signal electrode adjacent to the second layer is larger than a distance between the first layer and said signal electrode adjacent to said second layer, and a thickness of the ground electrode which includes the first layer and the second layer is 25 ?m or more.

Abstract: An optical waveguide device includes a substrate in which an optical waveguide is formed. The optical waveguide has a Y-branched structure in which light beams propagating through a main waveguide are branched into two parts, and a three-branched structure in which the optical waveguide is branched into three waveguides including the main waveguide and two sub-waveguides on both sides of the main waveguide at a front stage of the Y-branched structure. The main waveguide includes a linear waveguide portion in which a waveguide width is constant and a tapered waveguide portion in which the waveguide width gradually increases between the three-branched structure and the Y-branched structure.

Abstract: An optical communication module includes: an optical modulator that includes an optical modulation element housed in a rectangular parallelepiped container; a driver circuit that inputs a high-frequency signal to the optical modulation element; and a housing that houses the optical modulator and the driver circuit. An electrical interface is provided on one lateral surface of the housing, and an optical interface is provided on another lateral surface, which is opposite to the lateral surface, of the housing. In the optical modulator, an end of a wiring substrate, which is configured to introduce the high-frequency signal to the optical modulation element, is led out from one short-side side of the rectangular parallelepiped container, and the driver circuit is disposed between the short-side side of the optical modulator and the electrical interface.

Abstract: An optical element module includes a housing which houses an optical element, in which the optical element is optically coupled to an optical fiber introduced into the housing, the optical fiber is held by a fiber fixing part provided at the housing, the fiber fixing part includes, along a longitudinal direction thereof, a first tubular portion, a second tubular portion which is connected to a through-hole provided in the side wall of the housing and has an inner diameter substantially equal to an inner diameter of the through-hole and smaller than an inner diameter of the first tubular portion, and a tapered portion which continuously connects the first tubular portion and the second tubular portion, and the other end of a slit of the fiber fixing part reaches the tapered portion or the second tubular portion.

Abstract: Provided is an optical element module including: a substrate; an optical modulator unit that is formed in the substrate and includes an optical waveguide; a first lens unit that is disposed on an end surface of the substrate, and includes a lens portion at which a signal light beam emitted from the optical modulator unit is collimated; and a second lens unit that introduces the signal light beam passing through the first lens unit to an optical fiber.

Abstract: Modulation electrodes, bias electrodes, and bias electrodes are disposed in this order in a light wave-travelling direction in an optical modulation region modulating light having a wavelength. On the other hand, in an optical modulation region modulating light having a wavelength, the bias electrodes, the bias electrodes, and the modulation electrodes are disposed in this order in the light wave-travelling direction. That is, an order of the modulation electrodes and the bias electrodes in a longitudinal direction of a substrate is changed for each of the wavelengths.

Abstract: Provided is an optical modulator in which even in a case where an optical waveguide and a control electrode are highly integrated, a distortion due to stress acting on the optical waveguide from lead-out wiring of a signal electrode is mitigated and occurrence of a temperature drift or the like is suppressed.

Abstract: An optical modulator includes an optical modulation element including a plurality of signal electrodes and the like, a plurality of lead pins and the like for inputting radio frequency signals, and a relay substrate in which conductor patterns and the like that electrically connect the lead pins with the signal electrodes respectively are formed, the relay substrate is disposed so that a propagation direction of the radio frequency signals that have propagated through the lead pins is bent and guided to the conductor patterns, and the relay substrate is constituted so that widths of gaps between the plurality of conductor patterns in the optical modulator-side edge of the relay substrate is smaller than, preferably smaller than 50% of widths of gaps between the plurality of conductor patterns in the lead pin-side edge.

Abstract: An optical modulator includes: an optical modulation element which includes signal electrodes; lead pins; and a relay substrate in which a conductor pattern which electrically connects each of the lead pins and each of the signal electrodes to each other are formed, and the optical modulator is configured such that the amount of radiation of a high frequency at a connection portion between the conductor pattern and the signal electrode is increased compared to a portion other than the connection portion.

Abstract: Provided is an optical modulator in which an optical modulation element is accommodated in a housing. A plurality of lead pins, which are electrically connected to the optical modulation element through wire bonding, are fixed to the housing in a manner of protruding at least a part of each of the plurality of lead pins into the housing. In the plurality of lead pins, lengths of the lead pins are set to be different from each other so that a natural frequency of at least partial lead pins is different from a natural frequency of the other lead pins.

Abstract: An optical waveguide element module decreases discontinuity of electrical connection between an optical waveguide element and a relay substrate, without wire-bonding using long wires. An edge shape L of the signal electrode side of the ground electrode is surrounded by two shapes (L1, L2). Shape L1 is obtained by connecting an input end of the control electrode to a location where a space between the ground electrodes becomes W2. Shape L2 is such that an impedance change of the control electrode from the input end to the location at which the space between the ground electrodes becomes W2 is constant or continuously changes. A space between grounding wires connecting the ground electrodes of the element and ground lines of the relay substrate is larger than a space between the ground electrodes. In an embodiment, a terminal substrate and an output end of the control electrode are connected.

Abstract: Provided is an optical modulator module in which a modulation substrate having a plurality of optical modulation units is stored inside a package case. The optical modulator module includes a plurality of signal supply lines configured to supply a modulation signal to the optical modulation unit through a connector terminal which is introduced into the package case. At least two or more of the plurality of signal supply lines are set such that the signal supply lines have overall electrical lengths which are different from each other.

Abstract: An optical modulator includes an optical modulation element (102) including a plurality of signal electrodes (112a and the like), a plurality of lead pins (116a and the like) for inputting high frequency signals, and a relay substrate (118) in which conductor patterns (202a and the like) that electrically connect the lead pins and the signal electrodes are formed, and at least one of the conductor patterns in the optical modulator is constituted so that at least one resonant frequency of the at least one of the conductor patterns is different from at least one resonant frequency of at least one of the other conductor patterns.

Abstract: Modulation electrodes, bias electrodes, and bias electrodes are disposed in this order in a light wave-travelling direction in an optical modulation region modulating light having a wavelength. On the other hand, in an optical modulation region modulating light having a wavelength, the bias electrodes, the bias electrodes, and the modulation electrodes are disposed in this order in the light wave-travelling direction. That is, an order of the modulation electrodes and the bias electrodes in a longitudinal direction of a substrate is changed for each of the wavelengths.