Aiming at the difficulty of lack of fire extinguishing agent concentration testing equipment for aircraft fire extinguishing systems in my country, Dr. Lu Song carried out research on fire extinguishing agent concentration testing technology based on differential pressure method and infrared absorption method, and developed a fire extinguishing agent for aircraft fire extinguishing system based on differential pressure method and infrared absorption method. Concentration test equipment, the detection limit is increased from 0.5% volume concentration to ppm level, and the response time is increased from 250 milliseconds to 50 milliseconds. The equipment fills the gap in the domestic related fields, and the measurement accuracy and response time are no less than the technical level of the American FAA Halonyzer fire extinguishing agent concentration analyzer. Dr. Lu Song's research results have been published in internationally renowned journals such as Infrared Physics & Technology, Measurement Science and Technology, Optical Express, etc. The technology has been applied in the development of multi-type aircraft fire extinguishing systems.