The invention is a method and device for detecting the presence of impurities in fog and aerosols by measuring an electrical signal induced by the surface photo-charge effect, which depends on the type and concentration of the impurities. For this purpose, modulated radiation induces an electrical signal whose amplitude remains constant in pure fog but changes when an impurity appears. The method of measuring the presence of impurities in fog is carried out by means of a laser-induced surface photo-charge effect. The signal from fog generated by a liquid of known composition (pure liquid) is measured, then the signal from fog generated by a liquid of unknown composition is measured. If a different signal is obtained, then the difference ?V relative to the reference signal from pure fog will inform us about the presence and concentration of any impurity compound in the fog. The device for detecting the presence of impurities in fogs, using a laser-induced surface photo-charge effect, consists of a sensor with a liquid layer that generates a signal sensitive to the composition of the fog with which it is in contact. The sensor is irradiated with modulated laser radiation, and the generated signal is observed on a nanovoltmeter. The invention and method allow the detection of impurities in the composition of fog and aerosols, which can be used for environmental control, elimination of the consequences of pollution, in ecology, occupational safety, etc.
