As the diameter of optical elements increases

the polishing time increases sharply. The evaluation of the process

especially the tool stability will directly affect the polishing convergence efficiency and accuracy. According to the working conditions of the high-efficiency flexible bonnet polishing tool in the actual polishing

an experimental study on the stability analysis and evaluation of the bonnet tool is carried out in this paper. The optimum structural design analysis and active wear experiment of the bonnet tool with a spherical cap radius of 160 mm are carried out

and the performance evaluation method in design and production is proposed and verified. When the amplitude of polishing force increases abruptly

the polishing spot should be detected. Then

the surface roughness is less than 500 nm and the removal depth is less than 1.5 μm

it proves that the bonnet tool has reached its working life. Using the present evaluation standard

the wear degree and stability of the bonnet tool bit in use can be accurately judged.