Study on the lower limit of gas detection based on the snapshot infrared multispectral imaging system

Snapshot multispectral imaging system is extensively utilized in the petrochemical industry for gas monitoring due to its intuitive imaging, traceability, and ability to monitor a wide range of gases. Determining the detection capability of the different bands of the multispectral camera for the gases to be monitored is a crucial prerequisite for the operationalization of the camera. The current evaluation methods of detection capability are mainly for single-spectrum cameras, which require constructing complex experimental environments and have poor applicability to different gases. This paper proposes a radiation full-link simulation model, which can accurately calculate the degree of response and detection capability of each channel of the multispectral system for different types and concentrations of gases under various conditions. The gas detection capability of the self-developed uncooled multispectral gas cloud imaging camera was tested in the laboratory. Eleven industrial gases of different concentrations were detected, and the response error between the actual test results and the model simulation results was about 8.7%. This study is of great significance for the detection methods and applications of hazardous gases in chemical parks.