Optical chemical analysis apparatus

An optical chemical analysis apparatus comprising:

• an optical waveguide with a core layer that includes a light propagator, through which light can propagate in an extension direction of the light propagator, and a diffraction grating that connects optically to the light propagator;
• and
• a light source configured to inject the light into the diffraction grating by emitting incoherent light, wherein
• the diffraction grating further includes at least one light intake region for introduction of light from the light source,
• the diffraction grating includes a plurality of connected portions that connect optically to the light propagator, and
• the light source includes at least one light emitting point at a position such that a difference between an optical distance Lam to a point M, of the diffraction grating, that is a midpoint of a line segment connecting any two connected portions among the plurality of connected portions in plan view and an optical distance Lai to a closer one of the two connected portions is less than half of a wavelength, in a vacuum, of the light.

An optical chemical analysis apparatus comprising:

• an optical waveguide with a core layer that includes a light propagator, through which light can propagate in an extension direction of the light propagator, and a diffraction grating that connects optically to the light propagator;
• and
• a light source configured to inject the light into the diffraction grating by emitting incoherent light, wherein
• the diffraction grating further includes at least one 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 an area of the light intake region satisfying |sin(ΔP)|<0.1 is 50% or more of a total area of the light intake region, where a phase difference ΔP is a product of a difference ΔL and a wave number, in a vacuum, of the light (2π/wavelength in a vacuum), and the difference ΔL is a difference between a shortest optical distance Lab to the light intake region and an optical distance Lad to a certain point in the light intake region.