Fig. 1. Schematic diagram of measurement principle for distribution of high reflectivity on curved surface. (a) The initial ring-down cavity; (b) The test ring-down cavity; (c) The parallel beams incline after reflected by the curved mirror; (d) Establish a spherical coordinate system

Fig. 2. Schematic diagram of reflectivity distribution measurement device

Fig. 3. 5-dimensional degree-of-freedom motion control system

Fig. 4. Repeat the measurement 30 times at different positions

Fig. 5. Repeat the measurement of sample 1. (a) 2D reflectivity distribution map; (b) 2D standard deviation distribution map

Fig. 6. Grayscale image of laser intensity obtained by scanning sample 1 with laser confocal microscope

Fig. 7. Scanning results of sample 1. (a) 1D reflectivity scan diagram of measurement device; (b) 1D amplitude scan diagram of measurement device

Fig. 8. Comparison between true value and auto-scanning value. (a) Overall comparison of reflectivity; Reflectivity distribution histogram of (b) region Ⅰ, (c) region Ⅱ, and (d) region Ⅲ

Fig. 9. Repeated measurement sample 2. (a) 2D reflectivity distribution map of reflectance; (b) 2D standard deviation distribution map

Fig. 10. Repeated measurement sample 3. (a) 2D reflectivity distribution map of reflectance; (b) 2D standard deviation distribution map