PM2.5 fine particulate matter can be converted from oxides of sulfur and ammonia. Due to its strong activity, large surface area, and tendency to carry other types of toxic and harmful substances, it seriously affects human health.

With the process of industrialization, the scale of heavily polluting industries such as petroleum, chemical engineering, power, and metallurgy continues to expand. Inadequate pollution treatment has led to a worsening trend in overall atmospheric pollution; coupled with the sharp increase in the number of motor vehicles, this has caused an increase in the concentration of atmospheric particulate matter. PM2.5 refers to fine particulate matter in the atmosphere with a diameter of 2.5μm or less. Affected by conditions such as air pressure, temperature, and geographical environment, PM2.5 particles can remain suspended in the atmosphere for long periods. A higher concentration indicates more severe air pollution.

Currently, the main detection methods for PM2.5 include the oscillating microbalance method, electrochemical detection, and the weighing method. However, PM2.5 sensors manufactured based on these methods mostly suffer from shortcomings such as low detection sensitivity, single functionality, and low intelligence. Large-scale detection instruments with multiple particulate and gas detection functions are relatively expensive, bulky, and lack portability, making them unsuitable for ownership and use in public places, offices, and homes.

Since the turn of the new century, laser technology has not only developed rapidly in network transmission and communication but has also seen breakthroughs in measurement and sensing based on its high directionality and coherence. A laser sensor is a sensing device that uses laser technology for measurement. Laser sensors enable non-contact measurement with large range, high precision, strong anti-interference, and high speed. Laser dust sensors utilize the principle of laser scattering to perform photoelectric conversion of signals scattered by PM2.5 particles, amplifying the electrical signals to display the collected dust concentration. The PM2.5 detector developed based on laser PM2.5 dust sensor technology achieves large measuring range, high precision, strong anti-interference, and high speed.