Large size optical glass lens polishing based on ultrasonic vibration

The requirements for machining large size and high precision optical components are increasing with the rapid development of optical systems. In this paper, the process parameters (polishing paths, polishing path pitch and polishing inclination, etc.) of machining large-size optical convex lenses are optimized. The results show that the spiral path is the best pattern for uniformity of material removal at the corners, followed by Hilbert, while the scanning path has serious material removal non-uniformity at the corners. The influence of polishing path pitch on the uniformity of material removal was analyzed by theoretical calculations and the adjacent path pitch is optimized. Moreover, the effect of polishing inclination on machining accuracy is analyzed. In addition to the above parameters, the process parameters (spindle speed and feed speed, etc.) of ultrasonic vibration-assisted polishing were also optimized. A diameter of 300 mm large-size optical convex lens was polished, and excellent surface roughness (8 nm) was obtained by optimized process parameters. The novel method not only provides a theoretical basis for achieving deterministic removal, but also provides guidance for machining large-size workpieces. It also provides the basic theory for machining large-size, high-precision optical components.