Ultra-precision grinding of optical glass lenses with La-doped CeO₂ slurry

Higher accuracy and more efficient production of large aperture glass lenses is increasingly required for high-resolution imaging devices. These glass lenses are typically manufactured by both ultra-precision grinding and polishing. However, prolonged polishing deteriorates the lens shape accuracy and diminishes productivity. In order to reduce the required amount of polishing or even obtain a polish-free fine surface, chemical action-assisted ultra-precision grinding using La-doped CeO₂ slurry is proposed and its effectiveness is experimentally evaluated. The results show that the proposed grinding method successfully provides a high-quality surface comparable to a polished surface and results in five times higher productively than conventional grinding.