A PM particulate matter sensor is a device used to detect the particulate matter concentration in the air. Particulate matter refers to solid or liquid particles with a diameter of less than 100 micrometers, which can originate from natural environments (such as volcanic ash and dust storms) or human activities (such as industrial emissions and transportation). Excessive particulate matter concentration poses risks to human health, making continuous monitoring essential.

The working principles of the PM particulate matter sensor are as follows:

● Optical Sensors: These typically consist of a light source, a light beam collector, and a photodetector. The light source emits a beam, and the collector focuses it onto the photodetector. When PM particles pass through the beam, they cause light scattering. This scattered light is received by the photodetector and converted into an electrical signal, which is then processed to calculate the particulate matter concentration.

● Inductive Sensors: Usually composed of an induction coil and a voltage amplifier. The coil generates an induced voltage proportional to the quantity and size of the particles. The amplifier then boosts this voltage for output to subsequent circuits.

● Electrostatic Sensors: These typically include an electrostatic field generator, a dust collection plate, and a charge meter. Particles are adsorbed onto the plate under the influence of the electrostatic field. The charge meter measures the accumulated charge, which is proportional to the particulate matter concentration.

PM particulate matter sensors are widely used in environmental monitoring to protect public health, in industrial production to reduce emissions, and in healthcare to monitor respiratory health for early disease detection and treatment.