| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an injection mold which can prevent the deterioration of productivity while preventing the deterioration of optical characteristics caused by a weld line, in regard to a thin concave lens formed of resin. <P>SOLUTION: Heat insulating layers 14 and 24 having lower heat conductivity than that of a mold are provided on molding surfaces of a lens molding space 3. In the lens molding space 3, molten resin passing on the right side of an optical function molding portion 31 of a flange molding part 32 and molten resin passing on the left side of the optical function molding portion 31 of the flange molding part 32 out of the molding resin flowing in from gates 61 and 62 are made to associate with each other at the side of the flange molding part 32 opposite to gates 61 and 62. At this time, setting is performed so that the molten resin passing through the optical function molding portion 31 including the thinnest portion from the flange molding part 32 out of the molten resin made to flow into the lens molding space 3 from the gates 61 and 62 may reach the flange molding part 32 beyond a boundary between the optical function molding portion 31 and the flange molding part 32 at a side opposite to the gates 61 and 62. <P>COPYRIGHT: (C)2012,JPO&INPIT |
