Abstract: An optical waveguide element includes: a substrate; and a plurality of optical waveguides causing light to turn between a first direction and a second direction that is an opposite direction of the first direction in a plane of the substrate, the plurality of optical waveguides includes first portions extending in the first direction with a predetermined distance therebetween, second portions extending in a third direction that is different from the first direction, and third portions extending in the second direction, and each of the plurality of optical waveguides except for the optical waveguide in which the second portion extending in the third direction is located on an innermost side in the first direction intersects, at the third portion, another optical waveguide in which the second portion extending in the third direction is located further inward in the first direction.

Abstract: Provided is an optical waveguide element that prevents leaked light generated at a forking section from entering a downstream optical waveguide such as another forking section, thereby affording minimal degradation of optical characteristics. The optical waveguide is characterized in that: at least one of two fork waveguides (20a, 20b) forking from a first forking section (20) comprises a second forking section (21, 22); slab waveguides (3c-1 to 3c-3) are formed between the two fork waveguides; and between the first forking section and the second forking section, slits (41, 42) are formed that partition the slab waveguides into a first slab waveguide area (3c-1) close to the first forking section and second slab waveguide areas (3c-2, 3c-3) close to the second forking section(s).

Abstract: An optical waveguide element including a substrate, an optical waveguide formed on the substrate, and an electrode for controlling a light wave propagating through the optical waveguide, in which the optical waveguide and the electrode have an intersection in which the optical waveguide and the electrode intersect with each other, and at the intersection, the electrode has a multilayer structure including a plurality of metal layers made of a metal material, and a resin layer made of a resin material is formed between the electrode and the substrate.

Abstract: A titanium oxide powder of the present invention has a BET specific surface area of 5 m2/g or higher and 15 m2/g or lower and contains single-crystalline titanium oxide particles, in which a value (d10/d50) that is obtained by dividing a value (d10), which is obtained when a particle size distribution represented by a cumulative volume percentage of primary particle diameters of the titanium oxide particles is 10%, by a value (d50), which is obtained when a particle size distribution represented by a cumulative volume percentage thereof is 50%, is 0.3 or higher and 1 or lower, an amount of titanium oxide thereof is 99.0% by mass or more, and the titanium oxide powder has an anatase-type crystalline phase.

Abstract: An optical waveguide device includes a substrate on which an optical waveguide is formed, and a reinforcing block disposed on the substrate, along an end surface of the substrate on which an input portion or an output portion of the optical waveguide is disposed, in which an optical component that is joined to both the end surface of the substrate and an end surface of the reinforcing block is provided, a material used for a joining surface of the optical component and a material used for the substrate or the reinforcing block have at least different linear expansion coefficients of a direction parallel to the joining surface, and an area of a joining portion of the optical component is set to be smaller than an area of the end surfaces including joining portions of the substrate and the reinforcing block.

Abstract: An optical modulator according to the present invention comprises: a substrate which has electro-optic effects; an optical waveguide which is provided in the substrate; an optical fiber which is bonded to an end of the optical waveguide; a fixation member which is provided on an end part of the optical fiber; and an optical adhesive layer which bonds the optical fiber and the substrate to each other. The end of the optical waveguide is arranged in an end face of the substrate; the optical adhesive layer optically couples an end face of the optical fiber and an end of the optical waveguide with each other, while bonding the optical fiber, the fixation member and the substrate with each other; and the surface roughness of a surface of the fixation member, wherein the surface faces the end face of the substrate, is different from the surface roughness of an end face of the substrate, wherein the end face faces the surface of the fixation member.

Abstract: In an optical modulator, high frequency characteristics are improved and the stability thereof is improved. An optical modulator includes: an optical element substrate that includes an optical waveguide and a plurality of electrodes that control light waves propagating through the optical waveguide; and a package case that houses the optical element substrate, in which a plurality of signal input terminals, respectively electrically connected to the plurality of electrodes, are provided on the bottom surface of the package case, and the plurality of signal input terminals respectively electrically connected to the plurality of electrodes provided on the optical element substrate are divided and disposed on the sides facing each other with the optical element substrate interposed therebetween.

Abstract: An optical modulator that can effectively dissipate heat generated from the inside includes: an optical modulation element which includes an optical waveguide and a radio frequency electrode for controlling light waves propagating through the optical waveguide; a termination resistor electrically connected to the radio frequency electrode; a termination resistor board on which the termination resistor is disposed; and a package case, which houses the optical modulation element and the termination resistor board, in which a plurality of protrusion portions are formed on one external surface of the package case, and at least one of the protrusion portions is formed at a position on the external surface of the package case, which faces a position inside the package case where the termination resistor board is disposed with the package case in between.

Abstract: An initial change and a secular change in an optical characteristic and a high frequency characteristic in a case where an optical modulator is mounted in a package of an optical transmission apparatus are suppressed while improving a space utilization rate in the package of the optical transmission apparatus. An optical modulator that is electrically connected to an electric circuit configured on a circuit board, includes: a package that houses an optical modulation element; and a signal input part or the like for inputting an electric signal for causing the optical modulation element to perform an modulation operation from the electric circuit, in which the package has, on a part of a bottom surface facing the circuit board, a first protrusion portion protruding from the bottom surface, and the signal input part is provided on an upper surface of the first protrusion portion.

Abstract: An anti-fouling coating film of the present invention includes a component (A): zirconium; a component (B): lanthanum; and a component (C): at least one selected from the group consisting of silicon, phosphorus, and boron, in which in a case where masses of the component (A), the component (B), and the component (C) are used by being converted into masses of oxides thereof, total mass of the component (A) and the component (B) with respect to a mass of the anti-fouling coating film is 90% or more and 95% or less, and in a case where X is defined by X=mass of component (B)/(total mass of component (A)+component (B))×100, X is 20% or more and 50% or less, and the mass of the component (C) to the mass of the anti-fouling coating film is 5% or more and [6+(X?20)/6]% or less.

Abstract: A composite sintered body including: a metal oxide as a main phase; silicon carbide as a sub-phase; and silicate of a metal element that is included in the metal oxide, in which the average aggregation diameter of the silicate in the field of view of 600 ?m2 at a magnification of 1000 times is 5 ?m or lower.

Abstract: Provided is a composite sintered body for an electrostatic chuck, which is not easily broken even if it is exposed to high-power plasma. Further, provided are an electrostatic chuck device using such a composite sintered body for an electrostatic chuck and a method of manufacturing a composite sintered body for an electrostatic chuck. The composite sintered body for an electrostatic chuck is a composite sintered body including an insulating ceramic and silicon carbide, in which crystal grains of the silicon carbide are dispersed in at least one selected from the group consisting of a crystal grain boundary and a crystal grain of a main phase formed by sintering crystal grains of the insulating ceramic.

Abstract: An optical waveguide device including a rib-type optical waveguide 2 formed of a material having an electro-optic effect, and a reinforcing substrate 1 that supports the rib-type optical waveguide, one end of the rib-type optical waveguide 2 has a tapered portion 20, structures 4 are provided that are disposed apart from the tapered portion so as to sandwich the tapered portion and are disposed on the reinforcing substrate 1, an upper substrate is disposed above the tapered portion and the structures, and an adhesive layer is disposed in a space sandwiched between the upper substrate and the structures.

Abstract: Provided is a method for surface-modifying inorganic particles having a mixing step of mixing at least a surface-modifying material and the inorganic particles to obtain a liquid mixture and a dispersion step of dispersing the inorganic particles in the liquid mixture, in which a content of the inorganic particles in the liquid mixture is 10% by mass or more and 49% by mass or less, and a total content of the surface-modifying material and the inorganic particles in the liquid mixture is 65% by mass or more and 98% by mass or less.

Abstract: Provided is an optical modulator that can be driven at lower voltage through the use of differential signal output. An optical modulator includes a substrate 1 and optical waveguides (21, 22) and a control electrode that are formed on the substrate, in which the optical waveguide includes Mach-Zehnder type optical waveguide, the control electrode is provided with two ground electrodes sandwiching three signal electrodes; the three signal electrodes are constituted by second and third signal electrodes that sandwich a first signal electrode, and have a wiring structure in which one modulation signal of the differential signal is applied to the first signal electrode, and the other modulation signal of the differential signal is applied to the second and third signal electrodes; and one branched waveguide (21) out of two Mach-Zehnder type optical waveguides is disposed between the first and second signal electrodes, and the other branched waveguide (22) is disposed between the first and third signal electrodes.

Abstract: In a zinc oxide powder of the present invention, a content of a water-soluble substance is 0.30% by mass or less, and a mass ratio between an alkali metal and an alkaline earth metal which are included in the water-soluble substance is in a range of 1:2 to 10:1.

Abstract: Provided is a dispersion liquid for sealing a light-emitting element containing metal oxide particles having a refractive index of 1.7 or higher and a surface-modifying material at least partially attached to the metal oxide particles, in which a particle diameter D50 of the metal oxide particles when a cumulative percentage of a scattering intensity distribution obtained by a dynamic light scattering method is 50% is 30 nm or more and 100 nm or less, and a value D50/D90 obtained by dividing the particle diameter D50 of the metal oxide particles when the cumulative percentage of the scattering intensity distribution is 50% by a particle diameter D90 of the metal oxide particles when the cumulative percentage of the scattering intensity distribution is 90% is 0.20 or more.

Abstract: Provided is an optical waveguide element that prevents damage to a substrate and improves productivity. In an optical waveguide element in which an optical waveguide (24, 23) is formed on a substrate 1, a groove portion 3 is formed in at least a part of the substrate along an outer periphery 10 of the substrate 1.

Abstract: A dispersion liquid according to the present invention is a dispersion liquid containing metal oxide particles which have been surface-modified with a silane compound and a silicone compound, in which, when the dispersion liquid is dried by vacuum drying to separate the metal oxide particles, and a transmission spectrum of the separated metal oxide particles is measured in a wavenumber range from 800 cm?1 to 3800 cm?1 with a Fourier transform infrared spectrophotometer, Formula (1) below: IA/IB?3.5 is satisfied (in the formula, “IA” represents a spectrum value at 3500 cm?1 and “IB” represents a spectrum value at 1100 cm?1).

Abstract: A zinc oxide powder in which a BET specific surface area of the powder is 8 m2/g or more and 65 m2/g or less, an apparent specific volume measured by a loose packing method of the powder is 1.0 mL/g or more and 7.5 mL/g or less, and a value indicated by (the apparent specific volume measured by the loose packing method/an apparent specific volume measured by a tapping method), which is obtained by dividing the apparent specific volume (mL/g) measured by the loose packing method by the apparent specific volume (mL/g) measured by the tapping method of the powder, is 1.50 or more and 2.50 or less.