[China has made a series of breakthroughs in the field of optical measurement for traffic safety] September 20th. Recently, China has made a series of key breakthroughs in the field of optical parameter measurement technology for traffic safety. Relying on the State Administration for Market Regulation Key Laboratory (Measurement Optics and Applications) established by the Shaanxi Institute of Metrology, and based on the strategic layout of "Transportation Power" and "Safe China", we aim at the long-standing "unmeasured, incomplete, and unmeasured" problems in parameters such as visibility, retroreflection, and glare. We have carried out systematic research on measurement bottlenecks such as "precision" and broken through the core technical obstacles in the value traceability system. We have successfully developed a series of key optical parameter calibration devices, initially built an optical measurement and metrology technology system for traffic safety, and better protected the "visual lifeline" of traffic safety. At present, the series of results have been applied in civil aviation, road transportation, public safety and other fields. Among them, visibility and glare research results serve civil aviation operation guarantees, tunnel lighting optimization and urban light pollution control, laying a solid data foundation for transportation facility operation and maintenance management and decision-making and scheduling; retroreflection measurement technology provides key quantitative support for police and transportation equipment quality supervision and inspection, ensuring the effective implementation of relevant quality standards.