Abstract: To effectively prevent the acceleration of the drift phenomenon generated by the application of a high electric field to a substrate through a bias electrode in a waveguide type optical element. A waveguide type optical element includes a substrate (100) having an electro-optic effect, two optical waveguides (104 and 106) disposed on a surface of the substrate, a non-conductive layer (120) which is disposed on the substrate and is made of a material having a lower dielectric constant than the substrate, and a control electrode (150) which is disposed on the non-conductive layer and is intended to generate a refractive index difference between the two optical waveguides by respectively applying electric fields to the two optical waveguides, and the non-conductive layer is constituted of a material which includes silicon oxide, an oxide of indium, and an oxide of titanium and has a ratio between a molar concentration of the titanium oxide and a molar concentration of indium oxide of 1.

Abstract: Provided is an optical modulator including: a relay substrate; a first transmission line that is provided on a flat surface of the relay substrate, and transmits an electrical signal along the flat surface; a second transmission line that is provided separately from the relay substrate, is electrically connected to the first transmission line, and transmits, to the first transmission line, the electrical signal that has been input from an outer side in a direction that is not included in the flat surface; a modulation unit that modulates an optical signal by using the electrical signal that is transmitted by the first transmission line and the second transmission line; and a shield that shields a radiation component of the electrical signal that is radiated from the second transmission line.

Abstract: An aspect of the present invention is an optical modulator including a substrate, a plurality of optical waveguides, and a plurality of modulation electrodes provided on the substrate in order to modulate light propagating through the optical waveguides. The modulation electrodes include signal electrodes, to which modulation signals are supplied, and ground electrodes. The signal electrodes include first and second signal electrodes. The ground electrodes include a first ground electrode provided between the first and second signal electrodes, a second ground electrode provided on the opposite side of the first signal electrode from the first ground electrode adjacent to the first signal electrode, and a third ground electrode provided on the opposite side of the second signal electrode from the first ground electrode adjacent to the second signal electrode. A concave groove is formed in each of the first to third ground electrodes.

Abstract: Provided is an optical modulator including: a relay substrate; a first transmission line that is provided on a flat surface of the relay substrate, and transmits, along the flat surface of the relay substrate, an electrical signal that has been input from an outer side; a second transmission line that is provided in the relay substrate, and transmits the electrical signal in a direction that is not included in the flat surface; a modulation unit that modulates an optical signal by using the electrical signal that is transmitted by the first transmission line and the second transmission line; and a shield that shields a radiation component of the electrical signal that is radiated from a contact of the first transmission line and the second transmission line.

Abstract: An aspect of the present invention is an optical modulator including an electro-optic substrate, an optical waveguide, and a signal electrode for applying an electric field corresponding to a modulation signal to the optical waveguide. The electro-optic substrate includes a trench portion, which is formed by digging a surface of the electro-optic substrate, and a ridge portion, which is formed in a ridge shape by the trench portion so that an optical waveguide is provided. The trench portion includes a first trench portion, which is a trench portion between a pair of branched optical waveguides, and a second trench portion, which is a trench portion other than the first trench portion. Digging depths of the first and second trench portions are different.

Abstract: An optical waveguide device includes a substrate with an electro-optic effect on which an optical waveguide and an electrode for controlling optical waves propagating through the optical waveguide are formed and at least one light source for irradiating ultraviolet light on the substrate.

Abstract: An optical modulator has a ridge optical waveguide and a modulation electrode. The modulation electrode is composed of a signal electrode to which a modulation signal is supplied, a first ground electrode, and a second ground electrode, the signal electrode has a wide portion having a width wider than the width of the uppermost portion of the ridge optical waveguide, the first ground electrode has a central portion ground electrode component provided on a first surface so as to extend along a first direction, and the second ground electrode has a central portion ground electrode component provided on a second surface so as to extend along the first direction. The central portion ground electrode components respectively have a first and a second through-holes, and these through-holes overlap the wide portion of the signal electrode as seen in a planar view.

Abstract: Provided is an optical control device including first and second optical waveguides, a first control signal electrode including a first input-side signal electrode, a second control signal electrode including a second input-side signal electrode, an inter-signal-electrode ground electrode, a first ground electrode, and a second ground electrode. The substrate has a first groove that is provided between the first input-side signal electrode and the inter-signal-electrode ground, a second groove that is provided between the first input-side signal electrode and the first ground electrode, a third groove that is provided between the second input-side signal electrode and the inter-signal-electrode ground electrode, and a fourth groove that is provided between the second input-side signal electrode and the second ground electrode.

Abstract: An optical modulation device includes a substrate having a principal surface, and electrodes provided on the principal surface of the substrate. The electrodes have end portion regions on the outer edge side of the principal surface of the substrate in a plan view, and planar-view corner portions provided between tip end outer edges which define the tip end shapes of the end portion regions in a first direction and side surface outer edges which define the side surface shapes of the end portion regions in the plan view have chamfered shapes.

Abstract: The present invention provides an electro-optic element including an optical waveguide that is constituted of a core layer made of an inorganic compound and a first clad layer and a second clad layer which are laminated so as to sandwich the core layer therebetween and are made of a dielectric material, and a first electrode layer and a second electrode layer that are formed so as to sandwich the core layer therebetween, the first clad layer, and the second clad layer, in which at least one of the first clad layer and the second clad layer contains an organic dielectric material having an electro-optic effect, and refractive indices of the first clad layer and the second clad layer are lower than a refractive index of the core layer.

Abstract: Provided is an optical control element including a lithium niobate substrate, optical waveguides formed on the substrate, and electrodes for controlling light waves propagating through the optical waveguide, in which a temperature control element for substrate for controlling the temperature of the substrate is provided, and the temperature of the substrate is controlled using the temperature control element for substrate to be maintained at a temperature that is equal to or higher than a predetermined lower limit of temperature at which generation of a photo-refractive effect due to light propagating through the optical waveguide is suppressed and is equal to or lower than 80° C.

Abstract: A method according to an aspect of the present invention, is a method for manufacturing an optical waveguide element, including: an optical waveguide forming step of forming an optical waveguide extending in a first direction in a substrate by doping the substrate with an impurity for reducing a coercive electric field of the substrate, a ridge forming step of forming a first ridge part including the optical waveguide and a second ridge part intersecting the first ridge part, and a poling step of reversing a polarization direction of a region of the substrate divided by the second ridge part by applying voltage to the region.

Abstract: An optical modulator has a ridge optical waveguide and a modulation electrode. The modulation electrode is composed of a signal electrode to which a modulation signal is supplied, a first ground electrode, and a second ground electrode, the signal electrode has a wide portion having a width wider than the width of the uppermost portion of the ridge optical waveguide, the first ground electrode has a central portion ground electrode component provided on a first surface so as to extend along a first direction, and the second ground electrode has a central portion ground electrode component provided on a second surface so as to extend along the first direction. The central portion ground electrode components respectively have a first and a second through-holes, and these through-holes overlap the wide portion of the signal electrode as seen in a planar view.

Abstract: Provided is an optical control device including first and second optical waveguides, a first control signal electrode including a first input-side signal electrode, a second control signal electrode including a second input-side signal electrode, an inter-signal-electrode ground electrode, a first ground electrode, and a second ground electrode. The substrate has a first groove that is provided between the first input-side signal electrode and the inter-signal-electrode ground, a second groove that is provided between the first input-side signal electrode and the first ground electrode, a third groove that is provided between the second input-side signal electrode and the inter-signal-electrode ground electrode, and a fourth groove that is provided between the second input-side signal electrode and the second ground electrode.

Abstract: An aspect of the present invention is an optical modulator including a substrate, a plurality of optical waveguides, and a plurality of modulation electrodes provided on the substrate in order to modulate light propagating through the optical waveguides. The modulation electrodes include signal electrodes, to which modulation signals are supplied, and ground electrodes. The signal electrodes include first and second signal electrodes. The ground electrodes include a first ground electrode provided between the first and second signal electrodes, a second ground electrode provided on the opposite side of the first signal electrode from the first ground electrode adjacent to the first signal electrode, and a third ground electrode provided on the opposite side of the second signal electrode from the first ground electrode adjacent to the second signal electrode. A concave groove is formed in each of the first to third ground electrodes.

Abstract: An optical modulator that includes a substrate 1 composed of a material having an electro-optical effect, an optical waveguide 2 formed in the substrate, and a modulation electrode 3 for modulating lightwaves propagating through the optical waveguide, in which output light L2 that is output from the optical waveguide is guided with an optical fiber, wavelength dispersion characteristics of the optical fiber transmission line are compensated for by performing polarization reversal 10 of the substrate along the optical waveguide with a predetermined pattern so that the substrate along the optical waveguide has waveform distortion with characteristics that are inverse to the wavelength dispersion characteristics of the optical fiber transmission line, and the compensation for the wavelength dispersion characteristics is adjusted to a predetermined level by disposing an adjustment member made of a dielectric material or a metal material in the vicinity of the modulation electrode.

Abstract: A method according to an aspect of the present invention, is a method for manufacturing an optical waveguide element, including: an optical waveguide forming step of forming an optical waveguide extending in a first direction in a substrate by doping the substrate with an impurity for reducing a coercive electric field of the substrate, a ridge forming step of forming a first ridge part including the optical waveguide and a second ridge part intersecting the first ridge part, and a poling step of reversing a polarization direction of a region of the substrate divided by the second ridge part by applying voltage to the region.

Abstract: An aspect of the present invention is an optical modulator including an electro-optic substrate, an optical waveguide, and a signal electrode for applying an electric field corresponding to a modulation signal to the optical waveguide. The electro-optic substrate includes a trench portion, which is formed by digging a surface of the electro-optic substrate, and a ridge portion, which is formed in a ridge shape by the trench portion so that an optical waveguide is provided. The trench portion includes a first trench portion, which is a trench portion between a pair of branched optical waveguides, and a second trench portion, which is a trench portion other than the first trench portion. Digging depths of the first and second trench portions are different.

Abstract: Provided is a light control element wherein stable operation at low driving voltage is possible.

Abstract: Provided is an optical waveguide device capable of reducing stress that occurs inside an optical waveguide substrate due to a difference in a coefficient of thermal expansion. The optical waveguide device (10) includes an optical waveguide substrate (11) having a thickness of 30 ?m or less, and a liquid crystal polymer substrate (12) which holds the optical waveguide substrate (11) and has permittivity lower than that of the optical waveguide substrate (11). The optical waveguide substrate (11) and the liquid crystal polymer substrate (12) are bonded to each other by an adhesive layer (14).