| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent the jumping of a glass blank to be formed to the outside of a forming mold during the course of falling and the generation of a defective article by dropping the glass blank to be formed onto the forming surface of the lower mold by guiding means. SOLUTION: A ring of a position correcting means 4 having a ring of the diameter slightly larger than the diameter of the glass blank 5 to be formed is so arranged that its center aligns to the center 6a of the forming surface of the lower mold 6. The ring is then perpendicularly lowered and is pressed to the glass blank 5 to be formed. Further, the glass blank 5 to be formed is lowered while its curved surface is pushed by the ring, by which the glass blank 5 to be formed is moved in such a manner that its center 5a approaches the center 6a of the forming surface. The glass blank 5 to be formed is thus supplied to the forming surface of the lower mold 6. Next, the glass blank 5 to be formed is softened by heating until the viscosity thereof attains 10<5.5> to 18<8> , more preferably 10<6.5> to 10<7.6> poises and thereafter, the glass blank to be formed is subjected to press forming, by which the glass optical element is obtd.</p> |
