| 摘要 |
PURPOSE:To obtain optical parts of high accuracy in a large amount, by charging molten glass from the high-temperature side of a tunnel-shaped forming mold having a desired cross-sectional shape and temperature gradient, and extruding a glass rod of given shape from the low-temperature side. CONSTITUTION:Molten glass is charged from the high-temperature side of a tunnel-shaped forming mold having a temperature gradient. A pressure is applied to a top force 9 to form the molten glass in the mold into a desired shape and a glass column 34 is extruded. The molten glass in an amount corresponding to that of the extruded glass is recharged into the mold. The cycle is repeated and the glass column 34 is cut when the glass column 34 reaches the prescribed length. |
