JP2009035443A - Mold for glass molded lens and lens molding method - Google Patents

Abstract

An indented meniscus lens with a flange obtained by glass press molding needs to be press-molded by a conventional mold structure 6, and then the molded lens needs to be centered into a desired shape. For this reason, there were problems such as man-hours and cost increase due to centering and disposal of unnecessary glass.
In the present invention, in the case of a concave meniscus lens with an edge, the mold structure in which a convex upper mold 4 and a lower mold 5 provided with a minimum R are combined is the same as the desired lens shape, and In the case of a biconcave lens with an edge, the convex upper and lower mold structures 4 and 5 provided with a minimum R are the same as the desired lens shape, so press molding is performed after the glass material is put into these mold structures. Therefore, since the desired lens shape can be obtained without taking the desired lens shape into account, this is a molding method that is cost-saving and environmentally friendly.
[Selection] Figure 2

Description

  The present invention relates to an aspherical glass press-molded lens method capable of reducing the centering of a concave meniscus lens with an edge.

  A manufacturing method of an aspherical glass lens used for a digital camera or a projector includes a grinding method and a press molding method using a mold. However, a press molding method is advantageous for mass production at a low cost. With aspherical glass press-molded lenses, it is possible to produce lenses of various shapes such as convex lenses, convex meniscus lenses, and concave meniscus lenses.

In recent years, a centering-less lens that does not perform centering has been put to practical use in order to reduce the number of steps for convex lenses and edgeless concave meniscus lenses (see, for example, Patent Documents 1, 2, and 3). Since the concave meniscus lens with the edge is press-molded with a conventional mold structure as shown in FIG. 6, an unnecessary portion as shown in FIG. 5 is generated in the lens after press molding, and centering is required (see FIG. 5). The shaded part of 5 is the deleted part).
JP 2007-70215 A JP-A-11-32234 Japanese Patent Laid-Open No. 11-236230 JP 2007-91568 A

  The problem to be solved is the need to center the concave meniscus lens with an edge.

  The main feature of the present invention is that a minimum R mold is used as the upper mold.

  By using a mold having a minimum R on the molding surface and flat part of the convex mold, the molding method of the glass molded lens of the present invention can be centered because the molded lens is in the desired shape as it is. It becomes unnecessary. This eliminates the need for glass that has been discarded due to the reduction in man-hours and alignment, making it an environmentally friendly method. Moreover, the glass weight of an unnecessary part can be reduced and cost can be reduced.

  A desired shape can be obtained without centering the lens after molding.

(Embodiment 1)
FIG. 1 is a cross-sectional view of Embodiment 1 of a concave meniscus lens with a centering-less edge of the present invention,
FIG. 2 is a cross-sectional view of a mold assembly diagram for producing FIG. By using the mold structure as shown in FIG. 2, the structure of the mold becomes a desired lens shape as it is, so that the lens after molding is not centered, and a concave meniscus lens with a flange is easily completed. The range of the minimum R2 in FIGS. 1 and 2 is determined by the lens shape, and this time, the lens shape was used at R0.5.

(Embodiment 2)
FIG. 3 is a cross-sectional view of a second embodiment of the biconcave lens with a centering-less edge of the present invention, and FIG. 4 is a cross-sectional view of a mold assembly for producing FIG. By using the mold structure as shown in FIG. 4, the structure of the mold becomes a desired lens shape as it is, so that the lens after molding is not centered, and a biconcave lens with an edge is easily completed.

  The method for molding a glass molded lens according to the present invention can be used as a man-hour reduction, cost reduction, and environmentally friendly method by reducing the centering of a concave meniscus lens with an edge.

Explanatory drawing of the lens (centering-less) cross section after shaping | molding in Embodiment 1 of this invention Explanatory drawing of the die assembly cross section for producing the centering-less lens of Embodiment 1 of this invention Explanatory drawing of a lens (centering-less) cross section after molding in Embodiment 2 of the present invention Explanatory drawing of the die assembly cross section for producing the centering-less lens of Embodiment 2 of this invention Explanatory drawing of a cross section of a conventional concave meniscus lens after molding Explanatory drawing of a conventional mold configuration cross section

Explanation of symbols

1 Concave meniscus lens 2 Minimal R
3 Centering removal part 4 Upper mold 5 Lower mold 6 First trunk mold 7 Second trunk mold 8 Biconcave lens

Claims (3)

A molding die having a minimum R or R between a molding surface and a flat surface of one of upper and lower convex molds used for a glass press-molded lens. The molding die according to claim 1, which is used for a concave concave meniscus lens or a biconcave lens with a flange. A lens molding method for molding a lens using the molding die according to claim 1.

Images