Research progress on ultra-precision measurement technology based on line chromatic confocal sensors at micro-nano scale

Ultra-precision measurement technology is the cornerstone of ultra-precision machining and manufacturing technology, and is an essential component of the national modern advanced measurement system. chromatic confocal sensors (CCS), with their advantages of high accuracy, fast measurement speed, wide adaptability to tested surface, and non-contact measurement capability, have become an important research hotspot in the field of ultra-precision measurement. Due to the low scanning efficiency of point chromatic confocal sensors, which can only obtain height information for a single point at a time, line chromatic confocal sensors (LCCS) has developed rapidly in recent years. The LCCS can simultaneously obtain height information for thousands of points (such as 2048 points) along a line, and the three-dimensional topography of the measured surface can be obtained through several one-dimensional scans, greatly improving measurement efficiency. It has been widely applied in various advanced manufacturing fields. Firstly, the working principle of the LCCS is introduced, and the key components affecting its performance are analyzed. Then, the research progress of the LCCS is introduced, followed by the research progress of its metrological calibration. Next, the measurement applications of the LCCS are summarized. Finally, the application development of the LCCS are summarized and prospected.