To provide a means for preventing damage occurring on an optical functional surface of an optical device comprising a vitreous material having large abrasion factor which is caused by the conatct of the glass press molded article in the handling after molded and to provide a means for preventing from affecting the function of the finally resultant optical device even if the optical functional surface is damaged. 摩耗度の大きい硝材からなる光学素子であっても、ガラスプレス成形品がプレス成形後の取り扱い時に受ける接触によって、光学機能面にキズが生じない手段、又は、たとえキズが生じても、最終的に得られる光学素子の機能になんら影響しない手段を提供する。 - 特許庁