| 主权项 |
1. A method of manufacturing a barrel-integrated lens, in which a molded glass product is molded integrally with a barrel made of metal by means of a molten glass drop molding method,
said molten glass drop molding method being a method of, providing a lower die and an upper die, dropping a molten glass drop on said lower die, and then press molding said molten glass drop by said lower die and said upper die, said lower die including a lower cylindrical die, said lower cylindrical die having an optical surface for applying pressure to said molten glass drop at an upper end face of the lower cylindrical die and extending toward said upper die, said upper die including an upper cylindrical die, said upper cylindrical die being opposed to said lower cylindrical die, having an optical surface for applying pressure to said molten glass drop at a lower end face of the upper cylindrical die, and extending toward said lower die, said barrel including a through opening extending in an axial direction, said through opening including
a first cylindrical opening receiving said lower cylindrical die inserted therein during molding of said molten glass drop,a second cylindrical opening receiving said upper cylindrical die inserted therein such that a gap is produced in relation to the circumference of said upper cylindrical die during the molding of said molten glass drop, the second cylindrical opening having a diameter larger than a diameter of said first cylindrical opening, anda connection opening coupling said first cylindrical opening and said second cylindrical opening together, said method of manufacturing a barrel-integrated lens comprising the steps of: inserting said lower cylindrical die into said through opening from a side of said first cylindrical opening of said through opening such that an upper end portion of said lower cylindrical die is positioned part way in the axial direction of said first cylindrical opening to expose a portion of an inner circumferential surface of said first cylindrical opening; dropping a prescribed amount of said molten glass drop from a side of said second cylindrical opening such that said molten glass drop forms a substantially spherical shape by surface tension, while not contacting an exposed opening surface of said connection opening, said molten glass drop disposed in a region bounded by said upper end face of said lower cylindrical die and the portion of the inner circumferential surface of said first cylindrical opening; and inserting said upper cylindrical die into said through opening from the side of said second cylindrical opening, and press molding said molten glass drop by said lower cylindrical die and said upper cylindrical die such that said molten glass drop is pressure welded to said connection opening. |
