Infrared dust sensors use optical scattering as the principle and infrared LED as the light source to complete the detection of the numerical trend of particle concentration in the indoor air. When the light emitted by the LED meets the dust, the reflected light will be produced. At the same time, the light-sensitive detector can detect the light intensity of the reflected light, and the concentration of the dust can be judged according to the size of the pulse signal. Moreover, because the infrared LED light is beyond the luminescent spectrum, working with the sensitive element that can receive the corresponding spectrum can greatly weaken the influence of visible lights on the receiving elements.

The structure and circuit of infrared dust sensors are relatively simple. Due to problems such as light source intensity and receiver measurement accuracy, infrared dust sensors can only sense the signal of particles larger than 1μm. And because the sensor uses the heating resistor to promote the airflow, the sampling rate of the dust particle signal is low, and the data errors cannot be predicted. The high-precision infrared dust sensors we supply have characteristics of small sizes, low power consumption, short response time, stable operation under high dust concentration, etc. And they can be widely used in air purifiers, fresh air systems, air conditioners with purification functions and PM2.5 detectors.