MODULE OF OPTICAL PARTICLE SENSOR Russian patent published in 2020 - IPC G01N15/06 

FIELD: physics.

SUBSTANCE: invention describes a module of a laser sensor for determining density of fine particles. Laser sensor module includes: two lasers emitting measuring beams, an optical unit focusing the first and second measuring beams into the first and second measurement volumes, respectively. Unit has first and second numerical apertures relative to corresponding beams. Apertures are selected to detect a predetermined minimum particle size within a predetermined range of velocities. First measuring beam and the second measuring beam mutually form an angle φ between 10° and 160°. Module also has 2 detectors, each of which is designed to determine the first and second interference signals of self-mixing of the first and second optical waves in the first and second laser resonators of the first and second lasers, respectively. Module comprises evaluation unit receiving detection signals generated by detectors in response to certain self-mixing interference signals, wherein the unit determines first and second average particle velocities, respectively, by detection signals received in a predetermined period of time. Estimation unit also determines the first and second number of particles, respectively, based on the detection signals in a predetermined period of time, and then determines the density of particles based on the average particle velocity. Invention also relates to a method of determining particle density and a corresponding computer program product. Invention also relates to a mobile communication device (190) comprising such module (100) of a laser sensor.

EFFECT: simplified design and increased accuracy.

16 cl, 19 dwg