Abstract: Provided is an optical densitometer for measuring a density of a gas or liquid of interest, the optical densitometer comprising: a light source capable of introducing light into a core layer; a detector capable of receiving the light that has propagated through the core layer; and an optical waveguide, the optical waveguide comprising: a substrate; and the core layer comprising a light propagation portion capable of propagating the light in an extending direction of the light propagation portion, and a diffraction grating portion, the diffraction grating portion comprising a diffraction grating region and an extension region connected to the diffraction grating region, and a first optical coupling region included in the extension region and a second optical coupling region included in the light propagation portion being optically coupled with respect to the light propagating through the core layer.

Abstract: An optical waveguide includes a core layer which extends along a longitudinal direction and through which light can propagate; and a protective film that is formed on at least a portion of a surface of the core layer and has a smaller refractive index than the core layer. At least a portion of the protective film is provided in a manner allowing contact with a gas or a liquid. In a cross-section of at least a portion perpendicular to a longitudinal direction of the core layer, the protective film is formed around the entire surface of the core layer.

Abstract: A nonvolatile storage element includes a substrate; a gate region having a charge holding region and an insulator surrounding an entire surface of the charge holding region; a drain region formed in one of both sides of a lower portion of the gate region; and a source region formed in another one of both the sides. A halogen is distributed in the insulator to cover an entire surface of an upper surface of the charge holding region.

Abstract: There is provided a nonvolatile storage element having excellent charge holding characteristics capable of reducing variations in electric characteristics and an analog circuit provided with the same. A nonvolatile storage element is provided with a charge holding region and an insulator surrounding the entire surface of the charge holding region and having halogen distributed in at least one part of a region surrounding the entire surface.

Abstract: An optical chemical analysis apparatus (14) includes an optical waveguide (15) and a light source (17). The optical waveguide (15) has a core layer (12) that includes a light propagator (10), through which light can propagate in an extension direction, and a diffraction grating (first diffraction grating (11)) that connects optically to the light propagator (10). The light source (17) is configured to inject the light into the diffraction grating by emitting incoherent light. The diffraction grating further includes a light intake region for introduction of light from the light source, and the light source includes at least one light emitting point at a position such that the difference between the shortest optical distance Lab to the light intake region and the longest optical distance Lac to the light intake region is less than half of the wavelength, in a vacuum, of the light.

Abstract: An optical waveguide 15 includes a substrate 19, a core layer 12, a support 20, and a suppressing portion. The core layer 12 includes a light propagating portion 10 and a diffraction grating portion 11. The diffraction grating portion 11 includes a fine line pattern formed therein. The support 20 is made from a material having a smaller refractive index than a refractive index of the core layer 12. The support 20 supports the core layer 12 with respect to the substrate 19. The suppressing portion suppresses deformation of fine lines 13 that form the fine line pattern. The support 20 is not provided in an entire region between the light propagating portion 10 and the substrate 19 in a cross-section perpendicular to a longitudinal direction of the core layer 12 at least at a position in the longitudinal direction.

Abstract: It is an object of this invention to provide an optical waveguide, an optical concentration measuring device, and a method for manufacturing an optical waveguide capable of achieving an improvement of evanescent wave exuding efficiency of propagating light and light extraction efficiency. A core layer provided in an optical waveguide has a first portion having a first film thickness, a second portion having a second film thickness different from the first film thickness, and a third portion connecting the first portion and the second portion. The third portion is formed so that the film thickness is gradually increased from the second portion having the smaller film thickness toward the first portion having the larger film thickness between the first portion and the second portion, and the maximum inclination angle is 10° or more and 45° or less.

Abstract: An optical waveguide includes a core layer which extends along a longitudinal direction and through which light can propagate; and a protective film that is formed on at least a portion of a surface of the core layer and has a smaller refractive index than the core layer. At least a portion of the protective film is provided in a manner allowing contact with a gas or a liquid. In a cross-section of at least a portion perpendicular to a longitudinal direction of the core layer, the protective film is formed around the entire surface of the core layer.

Abstract: An optical waveguide (10) includes a substrate (15), a core layer (11) that extends along the longitudinal direction and through which infrared light IR can propagate, and a support (17) formed from a material with a smaller refractive index than the core layer (11) and configured to connect at least a portion of the substrate (15) and at least a portion of the core layer (11) to support the core layer with respect to the substrate (15). A connecting portion (171) of the support (17) connected to the core layer (11) is shifted from the position having the shortest distance from the center to the outer surface in a cross-section perpendicular to the longitudinal direction of the core layer (11).

Abstract: Sticking of core layer is suppressed, and deterioration of sensitivity of a sensor is prevented. An optical waveguide (10) includes a substrate (15), a core layer (11), a support, and a protrusion (18). The core layer (11) can transmit light. The support connects at least a portion of the substrate (15) and a portion of the core layer (11) together. The support supports the core layer (11). The protrusion (18) is arranged at a position different from a position of the support in a space between the substrate (15) and the core layer (11). The protrusion (18) has a maximum height at a position deviated from a central position cp of the core layer (11) in a width direction. The protrusion (18) protrudes toward the core layer (11) from the substrate (15).

Abstract: An optical chemical analysis apparatus (14) includes an optical waveguide (15) and a light source (17). The optical waveguide (15) has a core layer (12) that includes a light propagator (10), through which light can propagate in an extension direction, and a diffraction grating (first diffraction grating (11)) that connects optically to the light propagator (10). The light source (17) is configured to inject the light into the diffraction grating by emitting incoherent light. The diffraction grating further includes a light intake region for introduction of light from the light source, and the light source includes at least one light emitting point at a position such that the difference between the shortest optical distance Lab to the light intake region and the longest optical distance Lac to the light intake region is less than half of the wavelength, in a vacuum, of the light.

Abstract: An optical density measuring apparatus for measuring density of a gas or a liquid to be measured includes a light source capable of irradiating light into a core layer, a detector capable of receiving light propagated through the core layer, and an optical waveguide that includes a substrate and the core layer. The core layer includes a light propagation unit and a first diffraction grating unit that receives light from the light source and guides the light to the light propagation unit, which includes a propagation channel capable of propagating light in an extending direction of the light propagation unit. The first diffraction grating unit is disposed near to and facing a light-emitting surface of the light source. The first diffraction grating unit includes first diffraction gratings, at least two of which receive light emitted from the same light-emitting surface of the light source.

Abstract: The object of the present invention is to provide a current source which is capable of suppressing an increase in circuit size and by which a highly accurate constant current extremely stable to manufacturing variations or temperature fluctuations can be obtained. A current source circuit is provided with a nonvolatile storage element having a control gate region and a source region and operating as a field-effect transistor, and is configured to output a current in a state where a bias is applied between the control gate region and the source region.

Abstract: An optical density measuring apparatus and an optical waveguide capable of increasing the degree of design freedom are provided. The optical density measuring apparatus is for measuring density of a gas or a liquid to be measured and includes a light source capable of irradiating light into a core layer, a detector capable of receiving light propagated through the core layer, and an optical waveguide. The optical waveguide includes a substrate and the core layer, which includes a diffraction grating unit and a light propagation unit capable of propagating light in an extending direction of the light propagation unit. The diffraction grating unit and a portion of the core layer are separated in the thickness direction of the optical waveguide.

Abstract: This invention aims at providing a temperature characteristic adjustment circuit capable of adjusting the temperature characteristic to various positive and negative temperature characteristics with an excessively small characteristic variation and capable of suppressing an increase in the chip area and the current consumption with a simple circuit configuration. A temperature characteristic adjustment circuit has a current source having a nonvolatile storage element having a control gate region and a source region and driven by the application of a bias between the control gate region and the source region and an output circuit not having a nonvolatile storage element, in which the temperature dependency of an output signal originating from the temperature dependency of the current amount of a current output from the current source is adjusted by the nonvolatile storage element.

Abstract: According to the present disclosure, provided is an optical densitometer for measuring a density of a gas or liquid of interest, the optical densitometer comprising: a light source capable of introducing light into a core layer; a detector capable of receiving the light that has propagated through the core layer; and an optical waveguide, the optical waveguide comprising: a substrate; and the core layer comprising a light propagation portion capable of propagating the light in an extending direction of the light propagation portion, and a diffraction grating portion, the diffraction grating portion comprising a diffraction grating region and an extension region connected to the diffraction grating region, and a first optical coupling region included in the extension region and a second optical coupling region included in the light propagation portion being optically coupled with respect to the light propagating through the core layer.

Abstract: Sticking of core layer is suppressed, and deterioration of sensitivity of a sensor is prevented. An optical waveguide (10) includes a substrate (15), a core layer (11), a support, and a protrusion (18). The core layer (11) can transmit light. The support connects at least a portion of the substrate (15) and a portion of the core layer (11) together. The support supports the core layer (11). The protrusion (18) is arranged at a position different from a position of the support in a space between the substrate (15) and the core layer (11). The protrusion (18) has a maximum height at a position deviated from a central position cp of the core layer (11) in a width direction. The protrusion (18) protrudes toward the core layer (11) from the substrate (15).

Abstract: An optical waveguide 15 includes a substrate 19, a core layer 12, a support 20, and a suppressing portion. The core layer 12 includes a light propagating portion 10 and a diffraction grating portion 11. The diffraction grating portion 11 includes a fine line pattern formed therein. The support 20 is made from a material having a smaller refractive index than a refractive index of the core layer 12. The support 20 supports the core layer 12 with respect to the substrate 19. The suppressing portion suppresses deformation of fine lines 13 that form the fine line pattern. The support 20 is not provided in an entire region between the light propagating portion 10 and the substrate 19 in a cross-section perpendicular to a longitudinal direction of the core layer 12 at least at a position in the longitudinal direction.

Abstract: Sticking of core layer is suppressed, and deterioration of sensitivity of a sensor is prevented. An optical waveguide (10) includes a substrate (15), a core layer (11), a support, and a protrusion (18). The core layer (11) can transmit light. The support connects at least a portion of the substrate (15) and a portion of the core layer (11) together. The support supports the core layer (11). The protrusion (18) is arranged at a position different from a position of the support in a space between the substrate (15) and the core layer (11). The protrusion (18) has a maximum height at a position deviated from a central position cp of the core layer (11) in a width direction. The protrusion (18) protrudes toward the core layer (11) from the substrate (15).

Abstract: An optical density measuring apparatus and an optical waveguide capable of increasing the degree of design freedom are provided. The optical density measuring apparatus is for measuring density of a gas or a liquid to be measured and includes a light source capable of irradiating light into a core layer, a detector capable of receiving light propagated through the core layer, and an optical waveguide. The optical waveguide includes a substrate and the core layer, which includes a diffraction grating unit and a light propagation unit capable of propagating light in an extending direction of the light propagation unit. The diffraction grating unit and a portion of the core layer are separated in the thickness direction of the optical waveguide.