Abstract: A dielectric multilayer film is formed on one surface of a lens main body, a film including aluminum is formed on the other surface of the lens main body, the film including aluminum is immersed in hot water without immersing the dielectric multilayer film in the hot water, thereby changing the film including aluminum to a fine uneven structure film including an alumina hydrate as a main component, whereby a lens provided with antireflection functions on both surfaces is manufactured.

Abstract: A soundproof structure has one or more soundproof cells. Each of the one or more soundproof cells includes a frame having a through-hole, a film fixed to the frame, and an opening portion configured to include one or more holes drilled in the film. Neither end portions of the through-hole of the frame are closed. The soundproof structure has a shielding peak frequency, which is determined by the opening portion of each of the one or more soundproof cells and at which a transmission loss is maximized, on a lower frequency side than a first natural vibration frequency of the film of each of the one or more soundproof cells, and selectively insulates sound in a predetermined frequency band including the shielding peak frequency at its center.

Abstract: Provided is a method of manufacturing a structure having a transparent fine uneven structural body formed by hot water treatment, in which a finer uneven structure is formed. Provided is a method of manufacturing a structure, the method being for manufacturing a structure including a substrate, and a transparent fine uneven structural body which is formed on a surface of the substrate by hot water treatment, including: a first step of forming a precursor film of the transparent fine uneven structural body on the substrate; a second step of forming a fine uneven structure on a surface of the precursor film; and a third step of subjecting, to hot water treatment, the precursor film on which the fine uneven structure is formed to form the transparent fine uneven structural body in which a peak value ?0 of space frequency of the unevenness of the fine uneven structure formed in the second step satisfies ? <?0 (Expression I).

Abstract: Provided is a method of manufacturing a structure having a transparent fine uneven structural body formed by hot water treatment, in which a finer uneven structure is formed. Provided is a method of manufacturing a structure, the method being for manufacturing a structure including a substrate, and a transparent fine uneven structural body which is formed on a surface of the substrate by hot water treatment, including: a first step of forming a precursor film of the transparent fine uneven structural body on the substrate; a second step of forming a fine uneven structure on a surface of the precursor film; and a third step of subjecting, to hot water treatment, the precursor film on which the fine uneven structure is formed to form the transparent fine uneven structural body in which a peak value v0 of space frequency of the unevenness of the fine uneven structure formed in the second step satisfies v <v0 (Expression I).

Abstract: An antireflection film includes an uneven structure layer that has an uneven structure in which a distance between protrusions is shorter than a wavelength of light of which reflection is to be suppressed and has an alumina hydrate as a main component, and an intermediate layer that is disposed between the uneven structure layer and a substrate. The uneven structure layer has a spatial frequency peak value of the uneven structure of 6.5 ?m?1 or greater and a film thickness of 250 nm or more, and the intermediate layer is constituted of a plurality of layers including at least a first layer, a second layer, a third layer, a fourth layer, a fifth layer, a sixth layer, a seventh layer, and an eighth layer in this order from the uneven structure layer side to the substrate side.

Abstract: An antireflection film includes an uneven structure layer that has an uneven structure and has an alumina hydrate as a main component, and an intermediate layer that is disposed between the uneven structure layer and a substrate. The uneven structure layer has a spatial frequency peak value of the uneven structure of 8.5 or greater and has a film thickness of 200-250 nm, and the intermediate layer comprises a plurality of layers including at least a first layer, a second layer, a third layer, and a fourth layer.

Abstract: A soundproof structure has one or more soundproof cells. Each of the one or more soundproof cells includes a frame having a through-hole, a film fixed to the frame, and an opening portion configured to include one or more holes drilled in the film. Neither end portions of the through-hole of the frame are closed. The soundproof structure has a shielding peak frequency, which is determined by the opening portion of each of the one or more soundproof cells and at which a transmission loss is maximized, on a lower frequency side than a first natural vibration frequency of the film of each of the one or more soundproof cells, and selectively insulates sound in a predetermined frequency band including the shielding peak frequency at its center.

Abstract: An optical element includes: an optical element substrate; a first light shielding film that covers a non-optical path portion of the optical element substrate; a functional film that covers an optical path portion of the optical element substrate and the first light shielding film; and a second light shielding film that covers a non-optical path portion of the functional film, in which a region of the functional film which is not covered with the second light shielding film is transparent and has a uneven structure, and a region of the functional film which is covered with the second light shielding film has light reflecting properties. As a result, the optical element such as a lens is provided in which flare characteristics are excellent, and ghosting does not occur.

Abstract: The antireflection film is provided on a surface of a light-transmitting substrate and includes a thin multi-layer film and a fine unevenness layer that are laminated in this order from the substrate side. The thin multi-layer film includes multiple layers. The fine unevenness layer has a structure in which an uneven structure having a shorter average pitch than a wavelength of used light is provided and in which a refractive index to the used light changes continuously depending on a continuous change in a space occupation of the uneven structure in a thickness direction of the thin multi-layer film. The multiple layers include: an oxide film having a relatively high refractive index that is formed of at least two metal elements or is formed of silicon and at least one metal element; and an oxynitride film having a relatively low refractive index.

Abstract: The optical member includes: a transparent substrate; and an antireflection film that is formed on surface, in which the antireflection film includes a fine unevenness layer and an interlayer, the fine unevenness layer includes an alumina hydrate as a major component and has a uneven structure having a shorter distance between convex portions than a wavelength of antireflection target light, the interlayer is disposed between the fine unevenness layer and the transparent substrate, a peak value of spatial frequency of the uneven structure in the fine unevenness layer is higher than 6.5 ?m?1, and the interlayer includes at least three layers alternately including a low refractive index layer and a high refractive index layer.

Abstract: A dielectric multilayer film is formed on one surface of a lens main body, a film including aluminum is formed on the other surface of the lens main body, the film including aluminum is immersed in hot water without immersing the dielectric multilayer film in the hot water, thereby changing the film including aluminum to a fine uneven structure film including an alumina hydrate as a main component, whereby a lens provided with antireflection functions on both surfaces is manufactured.

Abstract: One lens is provided with a functional film formed of a fine uneven structure film throughout an entire region including an edge portion of a lens surface facing the other lens, and a portion of the fine uneven structure film formed in the edge portion is filled with a flattening member and is thus flattened. The lens is disposed so as to be in contact with the other lens in the edge portion in which the flattening member is formed, thereby assembling a lens assembly.

Abstract: An optical member includes a transparent substrate and an anti-reflection film. The anti-reflection film includes a refractive index gradient structure layer and an interference layer. A refractive index of the transparent substrate is different from a refractive index of the refractive index gradient structure layer on a side closest to the transparent substrate. A refractive index of the interference layer changes in the thickness direction, and has values which are discrete from both refractive indexes of the refractive index gradient structure layer and the transparent substrate at a boundary between the interference layer and the refractive index gradient structure layer and at a boundary between the interference layer and the transparent substrate, and a value thereof on a side close to the refractive index gradient structure layer is different from a value thereof on a side close to the transparent substrate.

Abstract: A first light-shied-coating formation step that forms a light shield coating only in a part of an area of a transparent-substrate in which a light shield coating is to be formed, a step that deposits an optical thin film including, as its outermost layer, a layer to be hydrothermally treated, which will become a fine uneven pattern coating by being hydrothermally treated, in an area in which an antireflection coating is to be formed, a second light-shield-coating formation step that forms a light shield coating in all of the area in which the light shield coating is to be formed, but the light shield coating was not formed in the first light-shield-coating formation step, and a step that forms the fine uneven pattern coating in the area in which the antireflection coating is to be formed by hydrothermally treating the layer to be hydrothermally treated are performed in this order.

Abstract: An antireflection film including a transparent thin film layer, and a transparent fine uneven layer whose main component is an alumina hydrate, which layers are formed in this order on a surface of a transparent substrate, is provided. The transparent thin film layer includes, in order from the transparent substrate side: an alumina layer; a water barrier layer which has a refractive index lower than the refractive index of the alumina layer and protects the alumina layer from water; and a flat layer whose main component is an alumina hydrate and whose refractive index is lower than the refractive index of the water barrier layer, and the water barrier layer has a thickness of 70 nm or less.

Abstract: A light diffusing element diffuses light output from an output facet of an optical fiber that enters the light diffusing element at a first end and outputting the diffused light from a second end. The light diffusing element is equipped with a semireflective surface for reflecting a portion of the light, provided at a predetermined portion of the light diffusing element corresponding to the core of the output facet. The semireflective surface intersects at least with the optical axis of the optical fiber. Thereby, propagation of light in directions away from the optical axis of the optical fiber can be promoted during the step of reflecting the portion of the light that enters the light diffusing element.

Abstract: A light source apparatus includes a first light source for emitting first light which is inputted to alight guide section that guides light to an examination area and projects the light onto the examination area and a second light source for emitting second light which is inputted to the light guide in which exit angles of the first and second light are changed simultaneously by an exit angle changing section, the first and second light being guided by the light guide section and projected onto the examination area.

Abstract: Provided is an optical connector including: an SI-type light source side optical fiber which is disposed on the light source side and an SI-type light receiving side optical fiber which is disposed on the light receiving side. Both optical fibers are optically coupled to each other by disposing an end surface of the light source side optical fiber and an end surface of the light receiving side optical fiber so as to face each other. The light source side optical fiber and the receiving side optical fiber are attachable to and detachable from each other. The light source side optical fiber includes a taper portion in which the diameter of the core portion increases toward the end surface of the light source side optical fiber.

Abstract: A light guide for an endoscope is equipped with an optical fiber. The optical fiber has an input side tapered portion and an output side tapered portion. The input side tapered portion is a predetermined portion of the optical fiber that includes an input end into which the illumination light enters the optical fiber, and the core of the optical fiber having a shape that becomes thicker toward the input end in the light input side tapered portion. The light output side tapered portion is a predetermined portion of the optical fiber that includes an output end through which the illumination light is output, and the core of the optical fiber having a shape that becomes thicker toward the output end in the light output side tapered portion. The core diameter at the input end is greater than the core diameter at the output end.

Abstract: A light diffusing element diffuses light output from an output facet of an optical fiber that enters the light diffusing element at a first end and outputting the diffused light from a second end. The light diffusing element is equipped with a semireflective surface for reflecting a portion of the light, provided at a predetermined portion of the light diffusing element corresponding to the core of the output facet. The semireflective surface intersects at least with the optical axis of the optical fiber. Thereby, propagation of light in directions away from the optical axis of the optical fiber can be promoted during the step of reflecting the portion of the light that enters the light diffusing element.