Abstract: A payment terminal includes a camera configured to capture an image, a card slot for inserting a contact type IC card, and a panel arrangement surface on which a touch panel is arranged. A lens of the camera, the card slot, and the panel arrangement surface are arranged in order in the height direction from a placement surface of the payment terminal. The panel arrangement surface is oriented obliquely upward toward a user positioned in front of the card slot. An optical axis direction of the lens is obliquely upward toward the user, and the lens is provided closer to the user than the card slot.

Abstract: A surface of a substrate is coated with a sol solution containing metal alkoxide. A gelled material of the sol solution is pressed against a molding tool while the gelled material is kept soft. Thus, the gelled material is molded. Then, the gelled material is hardened. As a result, protrusions of the hardened gel layer 14 are formed on the substrate so that an irregular texture substrate is formed. A multilayer thin film constituted by a plurality of layers of at least two kinds of materials with different refractive indexes is laminated on a surface of the irregular texture substrate.

Abstract: A surface of a substrate is coated with a sol solution containing metal alkoxide. A gelled material of the sol solution is pressed against a molding tool while the gelled material is kept soft. Thus, the gelled material is molded. Then, the gelled material is hardened. As a result, protrusions of the hardened gel layer 14 are formed on the substrate so that an irregular texture substrate is formed. A multilayer thin film constituted by a plurality of layers of at least two kinds of materials with different refractive indexes is laminated on a surface of the irregular texture substrate.

Abstract: Two lenses are used for forming a collimator parallel pair, in which the distance between the two lenses is substantially made coincident with the maximum distance allowing beam waists to be formed at equal distances from the two lenses respectively.

Abstract: A light source-optical fiber coupler constituted by: a light source (such as a semiconductor laser chip 10); and a gradient index rod lens 14 for coupling diffuse luminous flux emitted from the light source to an end surface of an optical fiber (such as a single mode optical fiber 16). The gradient index rod lens has a light source side end surface shaped like a convex spherical surface, and an optical fiber side end surface shaped like a flat surface. The gradient index rod lens is retained by the housing in the condition that the light source (laser chip) and the gradient index rod lens are disposed close to each other. The distance between a surface of the laser chip and an end surface of the gradient index rod lens is preferably selected to be not larger than 0.3 mm and more preferably in a range of from about 0.2 mm to about 0.25 mm.

Abstract: In an optical fiber-lens array, the optical axes of the gradient index rod lens and of the optical fiber are aligned easily with high accuracy. The optical fiber-lens array includes a first substrate having a gradient index rod lens accommodated in V-shaped grooves for rod lenses formed in parallel at prescribed pitches, and a second substrate having optical fibers accommodated in V-shaped grooves for optical fibers formed at the same array pitches with said V-shaped grooves for rod lenses. The first substrate and the second substrate are connected by guide pins placed on the common positioning guide grooves formed on the first substrate and the second substrate with the respective end surfaces of the gradient index rod lenses and the respective end surfaces of the corresponding optical fibers faced toward each other.

Abstract: Two lenses are used for forming a collimator parallel pair, in which the distance between the two lenses is substantially made coincident with the maximum distance allowing beam waists to be formed at equal distances from the two lenses respectively.

Abstract: A light source-optical fiber coupler constituted by: a light source (such as a semiconductor laser chip 10); and a gradient index rod lens 14 for coupling diffuse luminous flux emitted from the light source to an end surface of an optical fiber (such as a single mode optical fiber 16). The gradient index rod lens has a light source side end surface shaped like a convex spherical surface, and an optical fiber side end surface shaped like a flat surface. The gradient index rod lens is retained by the housing in the condition that the light source (laser chip) and the gradient index rod lens are disposed close to each other. The distance between a surface of the laser chip and an end surface of the gradient index rod lens is preferably selected to be not larger than 0.3 mm and more preferably in a range of from about 0.2 mm to about 0.25 mm.

Abstract: A wavelength monitoring apparatus according to the present invention constituted by: an optical device made of a periodic multilayer structure; a beam source optically connected to at least one end surface of the multilayer structure, the one end surface being not parallel to layer surfaces of the mutilayer structure; and a beam detecting means provided for detecting beam made to exit from at least one surface of the multilayer structure at a specific angle with respect to a specific wavelength, the one surface being parallel to the layer surfaces of the mutilayer structure.

Abstract: In an optical fiber-lens array, the optical axes of the gradient index rod lens and of the optical fiber are aligned easily with high accuracy. The optical fiber-lens array includes a first substrate having a gradient index rod lens accommodated in V-shaped grooves for rod lenses formed in parallel at prescribed pitches, and a second substrate having optical fibers accommodated in V-shaped grooves for optical fibers formed at the same array pitches with said V-shaped grooves for rod lenses. The first substrate and the second substrate are connected by guide pins placed on the common positioning guide grooves formed on the first substrate and the second substrate with the respective end surfaces of the gradient index rod lenses and the respective end surfaces of the corresponding optical fibers faced toward each other.