GLASS PREFORM AND METHOD OF PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To obtain a glass preform having a good surface state by removing unevenness formed on the surface of the glass preform and preventing sticking of foreign matters. SOLUTION: The surface of the glass preform is cylindrically ground using free abrasive grains having an average particle diameter (D50) of <=15μm when the unevenness formed on the glass preform is ground.