Abstract: A dual-passage air quality detection device includes a housing, an air quality detection module, a fan, and a main control PCB (printed circuit board). The air quality detection module includes two passages, two laser modules and two photodiodes therein. The fan includes two fans. One of the passages is communicated with the inside of the vehicle, and the other of the passages is communicated with the outside of the vehicle to form two independent air passages for detection. Each of the passages corresponds to one fan for independent sampling, not affecting each other.

Abstract: An air passage structure of a laser-type air quality detection module includes an air inlet passage, a primary air passage and a secondary air passage for accommodating a photoelectric element of the laser-type air quality detection module. A side wall of the secondary air passage is provided with a light entrance and a light exit facing the light entrance. The primary air inlet of the primary air passage and the secondary air inlet of the secondary air passage communicate with the air outlet of the air inlet passage. The secondary air inlet has a cross-sectional area less than that of the primary air inlet. Through the air passage structure, the service life of the laser-type air quality detection module can be prolonged.

Abstract: A dual-passage air quality detection device includes a housing, an air quality detection module, a fan, and a main control PCB (printed circuit board). The air quality detection module includes two passages, two laser modules and two photodiodes therein. The fan includes two fans. One of the passages is communicated with the inside of the vehicle, and the other of the passages is communicated with the outside of the vehicle to form two independent air passages for detection. Each of the passages corresponds to one fan for independent sampling, not affecting each other.