Gas detection apparatus

Abstract

A small-sized gas detection apparatus with high measurement accuracy is provided. The gas detection apparatus includes a light emitting portion (1); a light receiving portion (2); a first mirror (3) that has a quadric reflective surface and reflects light emitted from the light emitting portion; and a second mirror (4) that has a quadric reflective surface and reflects the light reflected by the first mirror to the first mirror. The quadric surfaces of the first mirror and the second mirror have convex portions facing in a same direction. The first mirror reflects the light reflected by the second mirror to the light receiving portion. When one surface of a substrate on which the light emitting portion and the light receiving portion are mounted is used as a reference plane, the first mirror and the second mirror are provided at positions higher than the reference plane and have different heights.

Dependencies are inferred from the claim text.