The present invention provides a polymer optical waveguide containing a core and a cladding having a refractive index lower than that of the core, in which each of the core and the cladding is a cured product of a curable composition cured by light irradiation, and the cladding has an absorbance of 0.23 or low per 50 m of film thickness at a wavelength of 365 nm.

Problem to Be Solved: to provide a chromophore having a far superior nonlinear optical activity to conventional chromophores and to provide a nonlinear optical element comprising said chromophore. Solution: a chromophore comprising a donor structure D, a -conjugated bridge structure B, and an acceptor structure A, the donor structure D comprising an aryl group substituted with a substituted oxy group; and a nonlinear optical element comprising said chromophore.

A method for producing an optical waveguide by: (a) depositing on a substrate a composition comprising: (i) a poly-siloxane comprising epoxy groups and alkenyl groups, (ii) a silane crosslinker having at least two silicon-hydrogen bonds and (iii) at least one compound comprising an epoxy group and a refractive index of at least 1.49; (b) heating; (c) depositing a second composition comprising: (i) a second polysiloxane comprising epoxy groups and alkenyl groups, and (ii) a second silane crosslinker having at least two silicon-hydrogen bonds; (d) curing by heating; (e) exposing to ultraviolet light through a mask to produce a patterned core layer; (f) heating to evaporate at least a part of the uncured portion of the first composition.

A plastic optical fiber including a first cladding; a first core forming a first sea portion inside the first cladding; and a first island portion formed inside the first core with at least an outer periphery having a lower refractive index than the first sea portion, wherein the first core includes a polymethyl methacrylate-based resin.

Nonreciprocal optical transmission devices and optical apparatuses including the nonreciprocal optical transmission devices are provided. A nonreciprocal optical transmission device includes an optical input portion, an optical output portion, and an intermediate connecting portion interposed between the optical input portion and the optical output portion, and comprising optical waveguides. A complex refractive index of any one or any combination of the optical waveguides changes between the optical input portion and the optical output portion, and a transmission direction of light through the nonreciprocal optical transmission device is controlled by a change in the complex refractive index.

Electro-optic (EO) devices having an EO polymer core comprising a first host polymer and a first nonlinear optical chromophore (NLOC); and a cladding comprising a second host polymer and a second NLOC, and methods of preparing the same; wherein the first NLOC has a first bridge covalently bonded to an electron-accepting group and an electron-donating group; wherein the second NLOC has a second bridge covalently bonded to an electron-accepting group and an electron-donating group; and wherein the second bridge is less conjugated than the first bridge such that the cladding has an index of refraction that is less than that of the EO polymer core, and wherein the second NLOC is present in the second host polymer in a concentration such that the cladding has a conductivity equal to or greater than at least 10% of the conductivity of the EO polymer core at a poling temperature.

A method for producing an optical waveguide by: (a) depositing on a substrate a composition comprising: (i) a poly-siloxane comprising epoxy groups and alkenyl groups, (ii) a silane crosslinker having at least two silicon-hydrogen bonds and (iii) at least one compound comprising an epoxy group and a refractive index of at least 1.49; (b) heating; (c) depositing a second composition comprising: (i) a second polysiloxane comprising epoxy groups and alkenyl groups, and (ii) a second silane crosslinker having at least two silicon-hydrogen bonds; (d) curing by heating; (e) exposing to ultraviolet light through a mask to produce a patterned core layer; (f) heating to evaporate at least a part of the uncured portion of the first composition.

Nonreciprocal optical transmission devices and optical apparatuses including the nonreciprocal optical transmission devices are provided. A nonreciprocal optical transmission device includes an optical input portion, an optical output portion, and an intermediate connecting portion interposed between the optical input portion and the optical output portion, and comprising optical waveguides. A complex refractive index of any one or any combination of the optical waveguides changes between the optical input portion and the optical output portion, and a transmission direction of light through the nonreciprocal optical transmission device is controlled by a change in the complex refractive index.

An illumination structure of the present invention is an illumination structure that lights a sunshade or a glass roof. The illumination structure includes: a frame-like first bracket coupled to a headliner along the circumferential edge of a headliner opening for reinforcing the headliner opening; a frame-like second bracket coupled to the first bracket so as to be overlaid on the back side of the first bracket for reinforcing the headliner opening in cooperation with the first bracket; and a light emitter held between the first bracket and the second bracket. Light from the light emitter is emitted through a gap between the first bracket and the second bracket.

An illumination structure of the present invention is an illumination structure that lights a sunshade or a glass roof. The illumination structure includes: a frame-like first bracket coupled to a headliner along the circumferential edge of a headliner opening for reinforcing the headliner opening; a frame-like second bracket coupled to the first bracket so as to be overlaid on the back side of the first bracket for reinforcing the headliner opening in cooperation with the first bracket; and a light emitter held between the first bracket and the second bracket. Light from the light emitter is emitted through a gap between the first bracket and the second bracket.