Active fire hazard detection cavity based on double light source excitation

The invention relates to an active fire hazard detection cavity based on double light source excitation, which is characterized in that a first light source and a second light source which emit light to the inside of a detection path and have different light source wavelengths are arranged on the same side of the detection path, and only one photoelectric sensor is arranged on the other side of the detection path; the scattered light reflected by the first light source or the second light source is reflected by the particulate matters flowing along with the air flow in the detection path; emergent light center lines of the first light source and the second light source are symmetrically arranged relative to a light receiving center line of the photoelectric sensor; the two light sources with different wavelengths are adopted as excitation to work alternately, and the same photoelectric sensor is shared for detection, so that the characteristic that different substances have different scattered light intensiti