| 摘要 |
PURPOSE:To prevent the cracking, etc., of the press-formed lens in the cooling stage by providing an escape part of specified shape for a surplus glass material on the periphery of a cavity forming an optical nonfunctional surface. CONSTITUTION:The forming mold consists of an upper mold 2, a lower mold 3, and a barrel mold 4 on an annulus ring, and the forming surfaces 2a and 3a of the upper mold 2 and lower mold 3 are specularly finished in the specified shapes corresponding to the functional surface of an optical lens to be formed. The escape part 5 is formed on the inner periphery of the upper end of the barrel mold 4. The depth of the groove of the escape part 5 is progressively decreased from the inner peripheral side toward the outer peripheral side. The glass formed in the escape part functions as the nonfunctional surface of an optical lens. When the optical lens is formed using the forming mold, the upper mold 2 is raised, softened glass material is placed on the lower mold 3, then the upper mold 2 is lowered, and the upper mold 2 is pressed for a time necessary to transfer the shapes of the forming surfaces 2a and 3a to the glass material 14. The whole mold is then cooled as such, the upper mold 2 is raised, and the glass formed product 6 is taken out. |
