Update: 2020-06-23 15:10 Source: LUFTMY
PM2.5 refers to airborne particles with a diameter of 2.5 microns or less, also known as lung-entering particles (there is no standard Chinese name).PM2.5 particles are small, less than 1/20 the thickness of a human hair.It is rich in a large number of toxic and harmful substances, stay in the atmosphere for a long time, long transportation distance, the impact on human health and atmospheric environment quality.Although PM2.5 is only a small component of the earth's atmosphere, it has a significant impact on air quality and visibility.
In aerodynamics, dust of less than 10 m diameter that can enter the alveolar area is commonly referred to as respiratory dust.Most of the dust particles with diameter of 10 m and above were deposited by impact. Most of the dust particles with diameter of less than 10 m were deposited in nasopharynx when inhaled, while the dust particles with diameter of less than 10 m could enter deep respiratory tract. Most of the dust particles deposited in alveoli were less than 5 m.
Global air pollution (PM2.5) is getting worse.It even seriously affects people's life and travel.In Europe, for example, when air pollution peaks, Paris, France, even stops traffic;Singapore's air pollution has also reached record highs;Air pollution in India is worse than in China.It can be seen that the problem of improving the environment is urgent.As ambient air quality monitoring is gradually derived from the general trend of indoor air quality monitoring in the city, various kinds of inhalable particles and gas sensors have become the core of sensing technology.The quality of the sensor directly affects the final air quality monitoring value, and plays a vital role in governance and control.
PM2.5 sensors, also known as dust sensors and particulate matter sensors, can be used to measure the concentration of dust, or PM2.5, in the air around us.The GDS06 infrared PM2.5 dust sensor developed by LUFTMY Utilizes the principle of optical scattering to obtain the concentration of particulate matter.This is because particles and molecules can scatter light and absorb some of the energy.When a beam of parallel monochromatic light is incident into the measured particle field, it will be affected by the scattering and absorption around the particle, and the light intensity will be attenuated.The relative attenuation rate of incident light passing through the concentration field to be measured can be obtained.The relative decay rate can basically linearly reflect the relative concentration of dust in the field under test.The intensity of the light is directly proportional to the intensity of the electrical signal through photoelectric conversion. The relative attenuation rate can be obtained by measuring the electrical signal, and then the concentration of dust in the field to be measured can be determined. Then, SCM is used for PWM and UART communication.