The disclosure relates to a panel comprising a first conductive layer that is transparent, a second conductive layer that is transparent, and a refractive-index-variable layer between the first conductive layer and the second conductive layer. A refractive index of the variable-refractive-index layer varies with a voltage applied between the first conductive layer and the second conductive layer.

The invention relates to a method of producing an optically transparent film, the method comprising the steps of: providing a ceramic material, wherein the ceramic material is transparent to light having a wavelength of from 380 nm to 1000 nm; and using electromagnetic radiation to adhere together at least some of the components of the ceramic material, wherein the electromagnetic radiation has a wavelength shorter than 450 nm.

Provided is an optical waveguide element capable of connection such as wire bonding, suppressing usage of gold, and suppressing deterioration of a conductor loss. An optical waveguide element includes a substrate 1 having an electro-optic effect, an optical waveguide 2 formed on the substrate, and a control electrode (30, 31) provided on the substrate and controlling a light wave propagating through the optical waveguide. The control electrode is made of a material other than gold, and the gold is disposed on at least a wire bonding portion 4 of the control electrode.

An asymmetric whispering gallery mode resonator device is described. The resonator device includes an asymmetric whispering gallery mode resonator disk (e.g., transparent material, electrooptic material). The resonator disk includes an axial surface along a perimeter of the resonator disk, a top surface, and a bottom surface. A first midplane passes through the axial surface dividing the axial surface into symmetrical halves. The top surface and the bottom surface are substantially parallel, and a second midplane is substantially equidistant between the top surface and the bottom surface. The first midplane and the second midplane are non-coextensive. The asymmetric whispering gallery mode resonator disk can further include a first chamfered edge between the top surface and the axial surface, and a second chamfered edge between the bottom surface and the axial surface. Moreover, the resonator device includes a first electrode on the top surface and a second electrode on the bottom surface.

An electro-optic modulator includes a doped semiconductor crystal having a crystallographic surface having an amplitude modulation orientation, a first metal electrode located on a first surface of the doped semiconductor crystal, a second metal electrode located on a second surface of the doped semiconductor crystal, and accumulation space charge regions located within surface regions of the doped semiconductor crystal that are proximal to the first metal electrode and the second metal electrode and including excess charge carriers of a same type as majority charge carriers of the doped semiconductor crystal.

A composite substrate for an electro-optic element is disclosed. The composite substrate includes: an electro-optic crystal substrate having an electro-optic effect; a low-refractive-index layer being in contact with the electro-optic crystal substrate and having a lower refractive index than the electro-optical crystal substrate; and a support substrate bonded to the low-refractive-index layer at least via a bonding layer. A plurality of interfaces located between the low-refractive-index layer and the support substrate includes at least one rough interface having a roughness that is larger than a roughness of an interface between the electro-optic crystal substrate and the low-refractive-index layer.

An optical modulator, a substrate for an optical modulator, a method of manufacturing an optical modulator, and a method of manufacturing a substrate for an optical modulator that can reduce a propagation loss are provided. An optical modulator 1 according to an embodiment includes: a base substrate 10; a waveguide substrate 20 disposed over the base substrate 10 and including an electro-optic effect; a waveguide 23 formed on the waveguide substrate 20 for performing optical modulation; and an electrode 40 configured to apply a voltage to the waveguide 23. Here, the base substrate 10 and the waveguide substrate 20 are made of the same material, the waveguide 23 is formed inside the waveguide substrate 20, and a refractive index of the waveguide substrate 20 is larger than a refractive index of the base substrate 10.

A functional element housing package includes a pin terminal disposed in an outer region of a housing for housing a functional element. A wiring substrate is connected with the pin terminal. The wiring substrate includes a through hole for receiving the pin terminal, a first metallic layer disposed around an opening of the through hole on a side of the wiring substrate which side is located close to the housing, a second metallic layer disposed around an opening of the through hole on a side of the wiring substrate which is opposed to the side located close to the housing, the second metallic layer being greater in area than the first metallic layer, a connection wiring line connected to the first metallic layer or the second metallic layer, and a solder which connects the pin terminal to each of the first metallic layer and the second metallic layer.

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.

A display panel includes a plurality of sub-pixels. At least one sub-pixel of the plurality of sub-pixels includes a first electrode, a light modulation structure disposed on a side of the first electrode, and a second electrode disposed at a side of the light modulation structure away from the first electrode. The light modulation structure includes a refractive index adjustment layer, and a light modulation layer disposed between the refractive index adjustment layer and the first electrode. A refractive index of the refractive index adjustment layer is changed under action of an electric field between the first electrode and the second electrode. The light modulation layer is in contact with the refractive index adjustment layer, and at least a part of a surface of the light modulation layer that is in contact with the refractive index adjustment layer is a curved face.