A nonlinear optically active copolymer having satisfactory orientation characteristics and able to allow for reduction in heat-induced orientation relaxation of a nonlinear optical material, and a nonlinear optical material obtained using the copolymer. The copolymer including at least a repeating unit A having adamantyl group and a repeating unit B having a nonlinear optically active moiety in one molecule, and an organic nonlinear optical material including the copolymer as a component.

Nonlinear optical chromophores having thiophene-containing bridging groups between the electron-donating and electron-accepting ends of the chromophore are disclosed, including bridging groups which contain cyclic moieties in combination with conjugated double bonds between the electron-donating and electron-accepting ends of the chromophore.

A fluid filled fiber for a quasi-phase matched generator and a laser incorporating such a fluid filled fiber. The laser has a liquid filled fiber with charge transfer molecules dissolved in a solvent. The liquid of the liquid filled fiber comprises or consists essentially of highly polar liquids and/or charge transfer molecules having relatively high molecular dipole values.

A fluid filled fiber for a quasi-phase matched generator and a laser incorporating such a fluid filled fiber. The laser has a liquid filled fiber with charge transfer molecules dissolved in a solvent. The liquid of the liquid filled fiber comprises or consists essentially of highly polar liquids and/or charge transfer molecules having relatively high molecular dipole values.

There is provided an optical wavelength conversion element with a good temporal stability and such a high optical wavelength conversion efficiency that the element is viable even under sunlight or similar, low intensity light. Owing to these properties, the element is suited for use in solar cells, photocatalysts, photocatalytic hydrogen and oxygen generating devices, photon upconversion filters, and like articles. The optical wavelength conversion element is visually homogeneous and transparent and produced by dissolving and/or dispersing in an ionic liquid (C) a combination of organic photosensitizing molecules (A) and organic light-emitting molecules (B) that exhibits triplet-triplet annihilation. The organic photosensitizing molecules (A) have either an only one local maximum absorption wavelength or a plurality of local maximum absorption wavelengths, and either the single local maximum absorption wavelength or a maximum one of the plurality of local maximum absorption wavelengths is from 250 nm to 499 nm.

There is provided an optical wavelength conversion element with a good temporal stability and such a high optical wavelength conversion efficiency that the element is viable even under sunlight or similar, low intensity light. Owing to these properties, the element is suited for use in solar cells, photocatalysts, photocatalytic hydrogen and oxygen generating devices, photon upconversion filters, and like articles. The optical wavelength conversion element is visually homogeneous and transparent and produced by dissolving and/or dispersing in an ionic liquid (C) a combination of organic photosensitizing molecules (A) and organic light-emitting molecules (B) that exhibits triplet-triplet annihilation. The organic photosensitizing molecules (A) have either an only one local maximum absorption wavelength or a plurality of local maximum absorption wavelengths, and either the single local maximum absorption wavelength or a maximum one of the plurality of local maximum absorption wavelengths is from 250 nm to 499 nm.

A display device includes: a first organic layer; display elements over the first organic layer in correspondence with the pixels; an inorganic layer sealing the display elements and the first organic layer; a second organic layer on a part of the inorganic layer; and a touch electrode on a surface of the inorganic layer and a surface of the second organic layer. The first organic layer has a rift in the peripheral area to surround the display area. The inorganic layer includes a concave part over the rift, and extends from the display area to the peripheral area continuously. The second organic layer is on the concave part of the inorganic layer. The surface of the second organic layer on which a touch electrode is put is contiguous to and is surrounded by the surface of the inorganic layer on the concave part.

A display device includes: a first organic layer; display elements over the first organic layer in correspondence with the pixels; an inorganic layer sealing the display elements and the first organic layer; a second organic layer on a part of the inorganic layer; and a touch electrode on a surface of the inorganic layer and a surface of the second organic layer. The first organic layer has a rift in the peripheral area to surround the display area. The inorganic layer includes a concave part over the rift, and extends from the display area to the peripheral area continuously. The second organic layer is on the concave part of the inorganic layer. The surface of the second organic layer on which a touch electrode is put is contiguous to and is surrounded by the surface of the inorganic layer on the concave part.

Nonlinear optical chromophores having thiophene-containing bridging groups between the electron-donating and electron-accepting ends of the chromophore are disclosed, including bridging groups which contain cyclic moieties in combination with conjugated double bonds between the electron-donating and electron-accepting ends of the chromophore.

A wavelength converter comprises: phosphor particles; and a matrix that is located between the phosphor particles and comprises zinc oxide crystallites. Pores are included in at least one of the zinc oxide crystallites.