JPH05337959A - Production of composite aspherical lens - Google Patents

Abstract

PURPOSE:To dispense with the wiping-off work of a protruding resin by a method wherein a resin sump expanding the molding space of a synthetic resin layer as compared with the spherical shape of a glass lens or the aspherical shape of a casting mold to the peripheral edge part of one of the glass lens and the casting mold and at least a part of the synthetic resin layer is allowed to flow in the resin sump. at the time of the molding of the synthetic resin layer. CONSTITUTION:A weighed resin material is dropped on the center part of a glass lens 11 and a casting mold 15 is allowed to approach the glass lens 11. Whereupon, the resin material within a molding space 17 moves to the periphery of the space and the excessive resin flows in a resin sump 12 before long. Therefore, when the resin material is polymerized and cured in this state, the wiping- off work of the excessive resin material becomes unnecessary. By this constitution, even when there is a weighing error in the injection amount of the resin, especially, an excessive weighing error, the wiping-off work of a protruding resin is not required and, therefore, a composite aspherical lens can be produced with excellent mass productivity.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a composite aspherical lens, which is formed by molding a synthetic resin layer on the surface of a glass lens.

[0002]

2. Description of the Related Art Composite aspherical lenses are
A spherical lens made of glass is processed by a well-known method, a weighed resin material is dropped on the surface of the processed glass lens, and the resin material is stretched with a mold having an aspherical shape and then polymerized and molded. It is manufactured by bonding on a glass lens. Therefore, the weighing of the resin material is inaccurate,
If the amount is less than the amount corresponding to the molding space, a molding failure will occur with a gap in the molding space, and if there is more, the injected resin will squeeze out to the lens outer peripheral portion. The former defect has no means for recovery, but the latter defect is resolved by wiping off the resin material that has squeezed out, so the amount of injected resin is generally measured in a slightly excessive direction. .. But,
The work to wipe off the protruding resin material is poor in workability,
Not suitable for mass-produced products.

[0003]

It is an object of the present invention to provide a method for manufacturing a composite aspherical lens in which a resin material is molded and bonded to the surface of a glass material by a mold, when the amount of injected resin has an excessive weighing error, or when it is positive. An object of the present invention is to obtain a method for manufacturing a composite type aspherical lens which is excellent in mass productivity and does not require a work of wiping off a protruding resin when giving a weighing error on the excess side.

[0004]

SUMMARY OF THE INVENTION The present invention has been completed based on the idea that a work for wiping off an excessive amount of injected resin is made unnecessary by forming a space into which the overflow resin is positively introduced. That is, the present invention is a method of manufacturing a composite type aspherical lens in which a synthetic resin layer made of an aspherical surface is adhered and molded on the surface of a spherical glass lens through an aspherical mold, and At least one peripheral edge is provided with a resin reservoir that expands the molding space of the synthetic resin layer more than the spherical shape of the glass lens or the aspherical shape of the mold, and at least a part of this resin reservoir is formed at the time of molding the synthetic resin layer. It is characterized by inflowing into.
According to this method, since the excess injected resin, whether intentional or not, flows into this resin reservoir, the work of wiping off the protruding resin is unnecessary, and the target aspherical shape is ensured. Can be obtained.

The adverse effect of the weighing error of the injected resin on the shape of the aspherical lens is remarkable in the lens in which the thickness of the synthetic resin layer is thinner in the peripheral portion than in the central portion of the optical axis. This is because the injected resin flows from the central part of the lens to the outer peripheral part. In that case, the weighing error is more likely to affect the shape accuracy when the peripheral part of the synthetic resin layer is thinner than when it is thick. Understood from. Therefore, when the present invention is applied to a lens in which the thickness of the synthetic resin layer is thicker in the central portion than in the peripheral portion of the compound lens, more remarkable effects can be obtained.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to illustrated embodiments. FIG. 1 shows a first embodiment of the manufacturing method according to the present invention. In this embodiment, a resin reservoir 12 is provided on the glass lens 11 side. The resin pool 12 is formed as follows. The glass lens 11 has a spherical surface 13 having a predetermined curvature. Usually this spherical surface 13
Maintained over the entire diameter of the glass lens 11,
In the present invention, the resin reservoir 12 is provided in the peripheral portion of the glass lens 11 in order to expand the resin molding space from the spherical surface 13. The resin reservoir 12 is provided in a portion that does not affect the lens performance, that is, outside the effective diameter.

The glass lens 1 manufactured as described above
1, an aspherical mold (mold) 15 is set on the surface on the side having the resin pool 12. The surface of the aspherical mold 15 facing the glass lens 11 constitutes a predetermined aspherical surface 16, and the glass lens 11 and the aspherical mold 1 are formed.
5, the molding space 17 of the synthetic resin layer is formed. The volume of the molding space 17 (volume including the resin pool 12) is
It can be calculated in advance. The amount of the injected resin material injected (dripping) into the molding space 17 is measured, for example, as an intermediate between the volume of the molding space 17 containing the resin puddle 12 and the volume of the molding space 17 not containing the resin puddle 12. .. That is, the injected resin material is weighed so as to be slightly larger than the volume of the molding space 17 in the case where the resin pool 12 is not present.

In molding, the weighed resin material is dropped on the center of the glass lens 11 to bring the mold 15 close to the glass lens 11. Then, the molding space 1
The resin material in 7 moves to the surroundings, and excess resin material eventually flows into the resin reservoir 12. Therefore, if the resin is polymerized and cured in this state, it is not necessary to wipe off the excess resin material. As shown in FIG. 2, the molded composite type aspherical lens 20 includes an aspherical resin layer 21 on a glass lens 11.
Is formed, and a part of the resin layer becomes the squeeze-out resin 22 that cures in the resin reservoir 12.

FIG. 3 shows a second embodiment of the present invention. In this embodiment, the glass lens 11A is not provided with a liquid pool, but the liquid pool 18 is provided on the aspherical mold 15A side. The liquid pool 18 is provided so that the resin molding space 17 is wider than the regular aspherical surface 16 of the aspherical mold 15A.

Also in this embodiment, since the excess injected resin material flows into the liquid pool 18, the wiping operation is unnecessary. According to this embodiment, as shown in FIG. 4, the aspherical resin layer 2 is formed on the composite type aspherical lens 20 after molding.
In addition to 1A, a protrusion resin corresponding to the liquid pool 18 is formed as a protrusion 22A. It is preferable that the protrusion 22A is provided at a position where removal work is unnecessary after molding. If the projection 22A is removed after the injected resin material is cured, stress is also applied to the aspherical resin layer 21A, which is not preferable.
In the first embodiment, the composite aspherical lens manufactured is
In this sense, the first embodiment is preferable because no protrusion corresponding to the protrusion 22A is formed.

In the present invention, the shapes and materials of the glass lenses 11 and 11A and the molding resin material do not matter. As the resin material, for example, an ultraviolet curable resin, a thermosetting resin or the like can be used. The surface of the glass lens 11 is coated with a predetermined adhesive in advance, and the aspherical surface 16 is coated with a predetermined release agent in advance.

[0012]

As described above, according to the present invention, in a method for producing a composite aspherical lens in which a resin material is adhered and molded on the surface of a glass lens by a mold, a weighing error in the amount of injected resin, particularly on the excess side, Even if there is a weighing error, it is not necessary to wipe off the protruding resin, so that it is possible to provide a method of manufacturing a composite-type aspherical lens having excellent mass productivity.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a method for manufacturing a composite aspherical lens according to the present invention.

2 is a cross-sectional view of a composite aspherical lens manufactured by the method of FIG.

FIG. 3 is a cross-sectional view showing a second embodiment of the method for manufacturing the composite type aspherical lens according to the present invention.

4 is a cross-sectional view of a composite aspherical lens manufactured by the method of FIG.

[Explanation of symbols]

 11 11A Glass Lens 12 18 Resin Reservoir 13 Spherical Surface 15 15A Aspherical Mold 16 Aspherical Surface 17 Molding Space 20 20A Composite Aspherical Lens 21 21A Aspherical Resin Layer 22 22A Overhanging Resin

Claims (2)

[Claims] 1. A method for producing a composite type aspherical lens, wherein a synthetic resin layer comprising an aspherical surface is adhered and molded on the surface of a spherical glass lens through an aspherical mold, wherein the glass lens and the mold are used. At least one of the peripheral edges is provided with a resin reservoir that expands the molding space of the synthetic resin layer more than the spherical shape of the glass lens or the aspherical shape of the mold. A method for manufacturing a composite type aspherical lens, which is characterized in that it flows into a pool. 2. The method for manufacturing a composite aspherical lens according to claim 1, wherein the thickness of the synthetic resin layer is thicker in the central portion than in the peripheral portion of the composite aspherical lens.