Abstract: An optical control device is provided which can suppress crosstalk between electrodes without increasing the entire size of the device itself. The optical control device includes a substrate having an electro-optical effect, an optical waveguide formed in the substrate, and a modulation electrode modulating optical waves propagating in the optical waveguide. The modulation electrode includes at least two signal electrodes and ground electrodes arranged to interpose the signal electrodes therebetween. The optical control device further includes an electrical connection member that electrically connects the ground electrode disposed between the two signal electrodes to other ground electrodes and that is disposed to cross over part of the signal electrode.

Abstract: An optical waveguide device module has an optical waveguide device including an optical waveguide formed in a substrate, and a control electrode for controlling light; and a connection substrate including an interconnection, provided to the outside of the waveguide device, electrically connected to the control electrode. The control electrode includes ground electrodes that sandwich a signal electrode. The connection substrate has ground lines that sandwich a signal line. A width of the signal electrode in an input or output end is smaller than a width of the signal line on the waveguide device side. A distance between inner edges of the ground electrodes closest to the signal electrode, measured at an input or output end of the control electrode, is larger than a distance between inner edges of the ground lines closest to the signal line on the waveguide device side of the connection substrate.

Abstract: An optical waveguide device module has an optical waveguide device including an optical waveguide formed in a substrate, and a control electrode for controlling light; and a connection substrate including an interconnection, provided to the outside of the waveguide device, electrically connected to the control electrode. The control electrode includes ground electrodes that sandwich a signal electrode. The connection substrate has ground lines that sandwich a signal line. A width of the signal electrode in an input or output end is smaller than a width of the signal line on the waveguide device side. A distance between inner edges of the ground electrodes closest to the signal electrode, measured at an input or output end of the control electrode, is larger than a distance between inner edges of the ground lines closest to the signal line on the waveguide device side of the connection substrate.

Abstract: An optical waveguide device module is provided, wherein a control electrode includes a signal electrode and ground electrodes disposed to sandwich the signal electrode, a connection substrate is provided with a signal line and ground lines disposed to sandwich the signal line, the distance W1 between the ground electrodes in the input end or the output end of the control electrode is larger than the distance W2 between the ground lines on the optical waveguide device side of the connection substrate, the control electrode has a portion of which the distance between the ground electrodes is smaller than the distance W2 in a portion away from the input end or the output end thereof, and interconnections of which the distance W between ground interconnections connecting the optical waveguide device and the connection substrate is at least smaller than the distance W1.

Abstract: An optical modulator is provided which can compensate for a bias shift between an output light and a monitoring light of the optical modulator and which has a configuration capable of being reduced in size with a simple structure. The optical modulator comprises a substrate that has an electro-optical effect, an optical waveguide that includes a Mach-Zehnder type optical waveguide formed in the substrate, a modulation electrode that modulates light waves propagating in the optical waveguide, an optical fiber that guides an output light from the optical waveguide, light collecting means for collecting two radiated lights from the Mach-Zehnder type optical waveguide toward a single optical receiving element, and light intensity ratio adjusting means for adjusting a light intensity ratio of the two radiated lights received by the optical receiving element.

Abstract: Disclosed is an optical waveguide element module in which a filter circuit including a capacitor is provided on a line through which a modulation signal is input to a modulating electrode of an optical waveguide element. The module is capable of preventing the deterioration of an electric signal in the filter circuit or the occurrence of a resonance phenomenon within the frequency range used and obtaining flat electrical/optical response frequency characteristics in a wide band of more than several tens of gigahertz. The capacitor is a single-layer capacitor and the relative permittivity of a dielectric in the capacitor is equal to or less than 1000.

Abstract: An optical modulator is provided which can compensate for a bias shift between an output light and a monitoring light of the optical modulator and which has a configuration capable of being reduced in size with a simple structure. The optical modulator comprises a substrate that has an electro-optical effect, an optical waveguide that includes a Mach-Zehnder type optical waveguide formed in the substrate, a modulation electrode that modulates light waves propagating in the optical waveguide, an optical fiber that guides an output light from the optical waveguide, light collecting means for collecting two radiated lights from the Mach-Zehnder type optical waveguide toward a single optical receiving element, and light intensity ratio adjusting means for adjusting a light intensity ratio of the two radiated lights received by the optical receiving element.

Abstract: An optical control device is provided which can suppress crosstalk between electrodes without increasing the entire size of the device itself. The optical control device includes a substrate having an electro-optical effect, an optical waveguide formed in the substrate, and a modulation electrode modulating optical waves propagating in the optical waveguide. The modulation electrode includes at least two signal electrodes and ground electrodes arranged to interpose the signal electrodes therebetween. The optical control device further includes an electrical connection member that electrically connects the ground electrode disposed between the two signal electrodes to other ground electrodes and that is disposed to cross over part of the signal electrode.

Abstract: An optical waveguide device module is provided, wherein a control electrode includes a signal electrode and ground electrodes disposed to sandwich the signal electrode, a connection substrate is provided with a signal line and ground lines disposed to sandwich the signal line, the distance W1 between the ground electrodes in the input end or the output end of the control electrode is larger than the distance W2 between the ground lines on the optical waveguide device side of the connection substrate, the control electrode has a portion of which the distance between the ground electrodes is smaller than the distance W2 in a portion away from the input end or the output end thereof, and interconnections of which the distance W between ground interconnections connecting the optical waveguide device and the connection substrate is at least smaller than the distance W1.

Abstract: Disclosed is an optical waveguide element module in which a filter circuit including a capacitor is provided on a line through which a modulation signal is input to a modulating electrode of an optical waveguide element and which is capable of preventing the deterioration of an electric signal in the filter circuit or the occurrence of a resonance phenomenon within the frequency range used and obtaining flat electrical/optical response frequency characteristics in a wide band of more than several tens of gigahertz, even though a single-layer capacitor is used as the capacitor.