| 摘要 |
An optical member for measuring a concentration, the optical member being capable of measuring with high accuracy from low concentration to high concentration, and the like are provided. Light (P1) emitted from a light source (P) for inspection is refracted at a boundary surface between an emitting surface (11b) of a first optical element (11) and a substance (7) to be measured, the substance circulating in a path (15), by an angle (¸ 2 ) of refraction depending on the concentration (refractive index) of the substance (7) to be measured. Furthermore, when the light is incident on a second optical element (12), the light is refracted to light (P3) parallel to a reference optical axis (O-O). When the light (P3) is emitted from the second optical element (12) to the outside, the light (P3) is further greatly refracted by magnifying means (16) provided on an emitting surface (12b) of the second optical element (12). |
