Luftmy is a domestic company focusing on the R&D, production, and sales of dust sensors. Currently, the infrared dust sensors sold include HPD05 and GDS06. The detection principles of these two different looking infrared sensors are basically the same, but there are some structural differences.

Infrared dust sensor principle

The shape of the HPD05 infrared dust sensor is relatively larger than the GDS06, with a semi-transparent air inlet window in the middle and the bottom circuit board exposed. The smaller GDS06 has its circuit board installed inside the sensor, with a round hole in the middle through which the airflow passes. When a beam of parallel monochromatic light is incident on the measured particle field, it will be affected by scattering and absorption around the particles, and the light intensity will be attenuated. In this way, the relative attenuation rate of the incident light passing through the concentration field to be measured can be obtained. The magnitude of the relative attenuation rate basically reflects the relative concentration of dust in the field to be measured linearly. The light intensity is proportional to the strength of the photoelectric-converted electrical signal. By measuring the electrical signal, the relative attenuation rate can be obtained, and then the dust concentration in the field to be measured can be determined.

The external designs of the HPD05 infrared dust sensor and the GDS06 infrared dust sensor are different, and their application choices in products also vary. The GDS06 sensor has a similar appearance to Sharp's dust sensor, so it is also universal. If the original product used Sharp's infrared dust sensor, it can be directly replaced.