AirMatrix sensors use optical measurement to determine the content of suspended particulate matter in the air. Currently, AirMatrix sensors allow to determine the content of fine particulate matter (PM2.5). A diode emitting infrared radiation and a detector in the form of a phototransistor, have been used in the device. The goal of the detector is to register the radiation reflected from the suspended particles, thanks to which it is possible to assess the content of the particles in the air. The detector converts the information concerning the quantity of the reflected radiation to voltage, proportional to the content of PM2.5 in accordance with the characteristics presented in the picture below.
The correctly constructed electronic system, manages the measuring procedure through activating the light source and detector in planned intervals. The flow of air through the device is forced by a fan, and the airflow is directed by a specially designed duct system. The developed algorithms for processing signals, analyze and convert the sensor’s measurements, ensuring a high reliability of the measurements in terms of the system’s various operations.