Focusing on CHANG AI's independently developed TDL laser core technology, this manual deeply analyzes the technical principles, product advantages, and industrial applications of the CI-PC66 series in-situ laser gas analyzers. Adopting a single-end reflective design, the product does not require sampling pretreatment and can directly measure multi-component gases such as O₂, CO, and NH₃. It can withstand harsh working conditions such as high temperature, high dust, and strong corrosion, with a response speed of up to 2 seconds. Widely used in process control and environmental monitoring in industries such as petrochemical, iron and steel, and electric power, it helps customers reduce costs, increase efficiency, and meet compliance standards with its characteristics of no cross-interference, maintenance-free, and high stability.