Method of manufacturing optical glass element

Abstract

A pair of upper die and lower die having forming surfaces corresponding to optical glass elements are prepared. A locating member having a plurality of locating holes for locating preforms is arranged on the lower die. A plurality of preforms are supplied to the locating holes, respectively, and the preforms are hot-press-molded between the paired upper die and lower die. According to this method, since a plurality of optical glass elements can be formed simultaneously, the high-precision optical glass elements can be manufactured at low cost.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are schematic views explaining an optical glass element forming method according to a conventional technique: FIG. 1A is the schematic view explaining the forming method using a single-cavity die set, and FIG. 1B is the schematic view explaining a plural-piece forming method using the single-cavity die set;

FIG. 2 is a schematic view explaining the optical glass element forming method according to a conventional technique;

FIG. 3 is a schematic view explaining the optical glass element forming method according to one embodiment of the present invention;

FIG. 4 is a sectional view schematically illustrating a state just before forming in the forming method in FIG. 3;

FIG. 5 is a perspective view schematically explaining a die in the forming method in FIG. 3 according to another embodiment;

FIGS. 6A and 6B are diagrams illustrating an optical glass element obtained by the forming method shown in FIG. 3: FIG. 6A is a plan view of the optical glass element, and FIG. 6B is a side view of the optical glass element; and

FIG. 7 is a diagram explaining a modified example of the present invention.

Claims

1. A method of hot-press-molding a preform between a pair of an upper die and a lower die so as to manufacture an optical glass element, the method comprising the steps of: arranging a locating member having a plurality of locating holes for locating the preform on the lower die;supplying the preforms to the locating holes, respectively; andhot-press-molding the preform between the paired upper die and the lower die.

2. The manufacturing method according to claim 1, wherein a forming surface of the lower die is a plane.

3. The manufacturing method according to claim 2, wherein a forming surface of the upper die has a shape such that a plurality of partially cylindrical surfaces is arranged in parallel.

4. The manufacturing method according to claim 3, wherein the plural locating holes are arranged separately into a matrix pattern so as to correspond to the partially cylindrical surfaces.

5. The manufacturing method according to claim 3, wherein the upper die is constituted so that a plurality of die block bodies having a partially cylindrical forming surface is arranged in parallel.

6. The manufacturing method according to claim 2, wherein both upper surface and lower surface of the preform are formed into planes.

8. The manufacturing method according to claim 1, wherein a pushing amount at the time of press molding is very small.

9. An optical glass element manufacturing apparatus, comprising: a lower die;a locating member which has a plurality of locating holes for locating preforms and is arranged on the lower die; andan upper die which hot-press-molds the preforms between the lower die between the lower die and the upper die.

10. The manufacturing apparatus according to claim 9, wherein a forming surface of the lower die is a plane.

11. The manufacturing apparatus according to claim 10, wherein a forming surface of the upper die has a shape such that a plurality of partially cylindrical surfaces is arranged in parallel.

12. The manufacturing apparatus according to claim 11, wherein the plural locating holes are arranged separately into a matrix pattern so as to correspond to the partially cylindrical surfaces.

13. The manufacturing apparatus according to claim 11, wherein the upper die is constituted so that a plurality of die block bodies having partially cylindrical forming surfaces is arranged in parallel.

14. The manufacturing apparatus according to claim 10, wherein both upper surface and lower surface of the preform are formed into planes.