OPTICAL DUST METER Russian patent published in 2019 - IPC G01N21/94 G01N15/02 

FIELD: ventilation and air conditioning.

SUBSTANCE: dust meter can be used for control of ventilation equipment, as well as for determination of total fraction of dust respirable fraction causing professional pulmonary diseases. Dust detector has a light source, two beam splitters, two diaphragms, two photodetectors, a laser range finder, a reflector, a CCD matrix, three analogue-to-digital converters and an electric computer. Light flux reflected from the first beam-splitting mirror is transmitted through the first diaphragm to the first photodetector, and the transmitted through the first beam-splitting mirror and the second diaphragm arrives at the second beam-splitter mirror. Portion of the light flux transmitted through the second beam-splitter mirror is projected onto the CCD matrix, and reflected from it is transmitted to the second photodetector. Laser range finder measures distance between centres of beam-splitter mirrors. Two photodetectors and CCD matrixes are connected to a computer via three analogue-to-digital converters.

EFFECT: high accuracy of continuous measurement of average concentration, as well as determination of average size of dust particles in the medium under study.

1 cl, 2 dwg