Infrared gas detection device based on vacuum tunneling current detection

The utility model discloses an infrared gas sensor based on vacuum tunneling current detection, which is characterized by comprising an infrared light source. An optical axis of the infrared light source is respectively provided with an open gas chamber for gas to be detected, a sealed gas chamber for the gas to be detected and a vacuum chamber with vacuum tunneling current; and infrared light from the infrared light source is projected into the sealed gas chamber via a light transmission glass plate after penetrating through an infrared optical filter and the open gas chamber, and the sealed gas chamber adopts an elastic diaphragm plate on the outer end side of the sealed gas chamber as a side end face of the vacuum chamber for changing a distance between two tunnel electrodes in the vacuum chamber. The infrared gas sensor has a simple structure, high detection precision and low monochromaticity requirements for the infrared light source.