Multimodal dust sensor

Abstract

The present invention relates to dust concentration measurement and to dust composition and particle size determination. Multimodal dust sensor is able to simultaneously determine the concentration, size and origin of dust particles in real time. Method of operation of a single measurement channel of the multimodal dust sensor comprises: collimating laser radiation; splitting the laser radiation into two beams: a first beam and a second beam; and focusing the first beam to form a probe volume, wherein a dust particle entering the probe volume: a) scatters the first beam, thereby providing a homodyne mode of operation, in which the second beam and the scattered first beam are combined; the combined radiation falls on the photodetector that registers the Doppler effect; and/or b) fluoresces, thereby providing a fluorescent mode of operation, in which the fluorescent light falls on the photodetector that registers the fluorescent light.