| 摘要 |
PURPOSE:To obtain a manufacturing method for forming an optical element provided with a collar part of prescribed thickness which has at least two faces required for positioning at the time of integrating a lens barrel into a part of the outside periphery, and in which other outside peripheral part is a free shape, and for forming simultaneously its optical element and the collar part. CONSTITUTION:On a part of a collar part 3 of the outside of an optical element having a first optical face 1 and a second optical face 2, positioning use faces 5-8 at the time of integrating it to a lens barrel are provided, and they are formed simultaneously by press forming. Subsequently, a glass blank 15 is put into a cavity which is limited by the upper die 9, the lower die 10 and a drum die 11 for press forming, heated by a heating means, and the glass blank 15 is softened enough. Next, by pressing it by a press rod, the glass blank 15 fills the inside of a cavity 14 of the outside, as well and a variance of the quantity of the blank 15 is absorbed, and also, the collar part 3 is formed, and moreover, by a projecting part 14, the positioning use faces 5-8 are formed in a prescribed part of the collar part 3. |
