JPH06198761A - Production of composite optical element - Google Patents

Abstract

PURPOSE:To obtain an inexpensive composite optical element having no damage on its optical surface and not restricted by the shape of a base material. CONSTITUTION:An energy curable resin layer 2 is interposed between a mold 1 having a molding surface 1a molding an optical function surface having a desired shape and a glass base material 2 having a diameter larger than that of the mold 1. The closely bonded molded object 4 consisting of the mold 4, the energy curable resin layer 3 and the glass base material is set so that the center 5 of the optical surface 2a having no resin layer of the glass base material 2 is positioned on the extension of the optical axis 6 of the desired molding surface 1a of the mold 1 before the energy curable resin layer 3 is cured and, thereafter, the energy curable resin layer 3 is cured. Thereafter, the outer peripheral part of the glass base material 2 is processed into a desired shape using a processing member 7 while the closely bonded member 4 is rotated around the optical axis 6 of the mold 1 and, thereafter, a composite optical element is released from the mold 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite optical element comprising a glass base material and an energy-curable resin layer formed on the surface of the base material.

[0002]

2. Description of the Related Art Conventionally, most of lenses which are optical components have been formed of glass. However, in the case of processing an aspherical lens in particular, the processing cost is much higher than that of a spherical lens. Therefore, as a method of manufacturing an optical component that solves this drawback, there is a method of manufacturing a so-called plastic lens, in which a transparent thermoplastic resin is injected into a mold and molded. This method can be mass-produced at low cost because it does not require polishing, but has a drawback that the focal length is erroneous because sink marks are more likely to occur during cooling after molding than glass materials.

As a manufacturing method for compensating for this drawback, an optical component comprising a glass base material and a resin layer is obtained by interposing a resin between a mold having a desired optical shape and the glass base material and curing the resin. There is a method of manufacturing a so-called composite optical element for forming. According to this method, since the resin layer is a thin film, the refractive index change due to thermal expansion and heat is small,
Furthermore, the occurrence of distortion and sink marks can be suppressed.

As a condition for obtaining high-precision optical performance in a general spherical glass lens, there is a high-precision optical core. This is called centering / centering, and similarly in the composite type optical element, the optical axis of the resin layer obtained by reversing the mold having the desired optical shape and the resin layer are not provided. It is necessary for optical performance that the spherical center of the optical surface of the glass base material is on the same straight line and that the optical axis and the center of the outer peripheral portion of the base material are aligned.

For this reason, the centering method using the bell clamp function is generally used for spherical glass lenses. Further, since the glass substrate centered with high accuracy is used in the composite optical element, it is necessary to align the optical axis of the glass substrate with the optical axis of the mold having a desired shape. As a general technique, there is a method described in JP-A-60-215551. This method is a method of positioning a base material and a mold processed with high precision using a parallel light beam, and after centering the base material, the optical axis of the base material (center of the outer diameter of the base material) The axis of the mold is aligned. In addition, JP-A-62-2
The method described in Japanese Patent Publication No. 27711 is a method in which a base material is positioned using a bell clamp, and is then molded by a mold having an optical axis that coincides with the center of the bell clamp. After the axis of the mold is aligned, the optical axis of the substrate (optical axis of the resin after molding) is aligned with the center of the outer diameter of the substrate. Further, the method described in JP-A-3-184813 is a method of positioning and molding the outer periphery of a substrate processed with high precision by a chuck or the like, and disclosed in JP-A-60-215551.
After centering the base material, the optical axis of the base material (center of the outer diameter of the base material) and the axial center of the mold are aligned, as in the publication.

[0006]

However, the above-mentioned prior art has the following problems. In the method by the bell clamp mechanism used in the spherical glass lens,
Since the optical element is sandwiched between the bell holders, the composite optical element, which has a resin layer on one side, scratches the bell holder on the resin layer and cannot be used as an element. on the other hand,
The method using a parallel light beam is not only very expensive due to the complexity of its equipment, but also requires a long time for positioning, resulting in a long molding cycle time, and the resulting composite optical element is expensive and mass-produced. It was difficult to apply to things. Further, the method of first performing the centering of the base material by the bell clamp cannot accurately position the base material having a curvature larger than the outer diameter, and thus the shape of the base material is limited. Furthermore, the method of holding the outer periphery of the base material with a chuck or the like causes the base material to be deformed or damaged by the holding force when a thin base material is used. There were restrictions.

The present invention has been made in view of the above problems in the prior art, and it is an object of the present invention to provide a method for manufacturing a composite optical element which has no scratch on the optical surface, is inexpensive, and has no restriction on the shape of the substrate. To aim.

[0008]

In order to solve the above-mentioned problems, the present invention is a method for producing a composite-type optical element in which an energy-curable resin layer is formed on one surface of a glass material. In the method of manufacturing a composite optical element, wherein the optical functional surface is transferred to the resin by a mold so that the optical axis passes through the spherical center of the other surface (optical functional surface) of the glass substrate, When transferring the optical functional surface, the resin is brought into close contact with the mold to form an integrated contact molded body of the mold, the resin and the glass base material, and the outer diameter of the glass base material is set to a predetermined value while maintaining the close contact state. It was decided to process into the shape of.

FIG. 1 is a conceptual diagram showing the manufacturing method of the present invention. The means for solving the above problems will be shown below with reference to FIG. Forming surface 1a for forming an optically functional surface having a desired shape
1 having a glass and a glass substrate 2 having a diameter larger than the outer diameter of the die 1
The energy-curable resin layer 3 is interposed between and. The contact molding 4 comprising the mold 1, the energy curable resin layer 3 and the glass substrate 2 is an extension of the optical axis 6 of the desired molding surface 1a of the mold 1 before the energy curable resin layer 3 is cured. After positioning so that the spherical center 5 of the optical surface 2a of the glass base material 2 on which the resin layer is not formed is positioned above, the energy curable resin layer 3 is cured.

After that, the outer peripheral portion of the glass substrate 2 is processed into a desired shape by using the processing member 7 while rotating the contact member 4 around the optical axis 6 of the mold 1, and then the composite optical element is moved from the mold 1. Release.

[0011]

Example 1 FIGS. 2A to 2D are manufacturing process diagrams of a method of manufacturing a composite optical element according to this example. First, FIG.
As shown in (a), a meniscus-shaped optical glass BSL having an outer diameter of 40 mm and a radius of curvature of 100 mm and 80 mm.
-7 A required amount of the ultraviolet curable resin 11 is discharged onto the molding surface of the glass base material 2. Since the glass base material 2 is not centered, the optical axis does not coincide with the center of the outer peripheral portion of the glass base material 2, but the optical surface 2a on which the resin layer is not formed by being placed on the bell holder 12 The core 14 of
Regardless of how the glass substrate 2 is placed, it is always at the same position. The mold 1 having an outer diameter of 35 mm is a molding surface 1a having a desired surface shape.
Holds and can slide up and down.

FIG. 2B shows a state in which the mold 1 is lowered from the state of FIG. 2A and the ultraviolet curable resin 11 is spread by the molding surface 1a having a desired surface shape. At this time, the mold 1 is accurately held so that the spherical center 14 of the optical surface 2a on which the resin layer of the glass substrate 2 is not formed is coaxial with the optical axis 13 of the molding surface 1a of the mold 1. In addition, the resin thickness of the formed resin layer 3 is also a required thickness. In this state, the resin layer 3 is cured by irradiating the glass substrate 2 with ultraviolet rays from the bell holder 12 side, and the contact molding 4 including the mold 1, the resin layer 3 and the glass substrate 2 is obtained.

Next, as shown in FIG. 2 (c), the contact molding 4 obtained by the above-mentioned method is moved by the optical axis 13 of the mold 1 at 150 r.
While rotating at pm, # 500 around the outer circumference of the glass substrate 2.
The desired outer dimension of 38 mm is processed by the grindstone 7.
At this time, the grindstone 7 was processed while rotating at 3000 rpm. After that, by releasing from the interface between the mold 1 and the resin layer 3, the composite optical element 20 as shown in FIG. 2D was obtained.

The composite optical element 20 has a resin layer 3 having a desired surface shape obtained by accurately reversing the surface shape of the mold 1.
And the spherical center 14 of the optical surface 2a on which the resin layer 3 of the glass substrate 2 is not formed is present on the axis 15 that is coaxial with the optical axis of the desired surface shape, and The center of the diameter 2b and the axis 15 (the optical axis of the desired shape) coincided with each other, and the quality was high. Further, the optical surface of the obtained resin layer 3 did not have scratches that would cause a problem in appearance.

In this embodiment, the meniscus-shaped glass base material 2 made of BSL-7 was used, but the same effect can be obtained by using other glass materials, or glass base materials having other shapes such as biconcave or biconvex. . Further, the same effect can be obtained by changing the roughness of the grindstone 7 and the number of rotations at the time of processing the outer periphery depending on the glass material or the shape of the glass substrate. Further, the resin used may be a thermosetting resin, an electron beam curable resin, or another energy curable resin other than the ultraviolet curable resin.

[0016]

[Embodiment 2] FIGS. 3A to 3C are manufacturing process diagrams of a method for manufacturing a composite optical element according to this embodiment. Figure 3 (a)
Is a biconvex optical glass BSL- with an outer diameter of 40 mm having a radius of curvature of 50 mm and 60 mm, which is adsorbed and held by a bell holder 12 on a thermosetting resin discharged onto a molding surface 1a of a desired shape of a mold 1. 7 shows a state in which a desired resin layer 3 is formed by pressing and spreading the glass base material 2 made of glass. Since this glass substrate 2 is not centered, the optical axis and the center of the outer peripheral portion of the glass substrate 2 do not coincide, but the resin layer 3 is formed by being sucked and held by the bell holder 12. The spherical center 14 of the optical surface 2a is always at the same position regardless of how the glass substrate 2 is placed. Further, the molding surface 1a of the mold 1 having an outer diameter of 35 mm is accurately held so that the spherical center 14 is aligned with the optical axis 13. Further, the resin thickness of the formed resin layer 3 is also a required thickness. In this state, the temperature is set to 80 ° C. to cure the resin layer 3 and obtain the contact molding 4 including the mold 1, the resin layer 3 and the glass substrate 2.

Next, as shown in FIG. 3 (b), the contact molding 4 obtained by the above-mentioned method is moved by the optical axis 13 of the mold 1 at 150 r.
While rotating at pm, # 500 around the outer circumference of the glass substrate 2.
The desired outer dimension of 38 mm is processed by the grindstone 7.
At this time, the grindstone 7 was processed while rotating at 3000 rpm. After that, by releasing from the interface between the mold 1 and the resin layer 3, a composite optical element 20 as shown in FIG. 3C was obtained.

The composite optical element 20 has a resin layer 3 having a desired shape obtained by accurately reversing the surface shape of the mold 1, and an axis 15 coaxial with the optical axis of the desired surface shape. The spherical center 14 of the optical surface 2a on which the resin layer of the glass substrate 2 is not formed exists, and the center of the outer diameter 2b of the glass substrate 2 and the axis 15 (the optical axis of the desired surface shape) are aligned. Had high precision quality. Further, the optical surface of the obtained resin layer 3 did not have scratches that would cause a problem in appearance.

In the present embodiment, the meniscus-shaped glass base material 2 made of BSL-7 was used, but the same effect can be obtained by using another glass material, or a glass base material having another shape such as a biconcave shape or a meniscus shape. . Further, the same effect can be obtained by changing the roughness of the grindstone 7 and the number of rotations at the time of processing the outer periphery depending on the glass material or the shape of the glass substrate. Further, the resin used may be a thermosetting resin, an electron beam curable resin, or another energy curable resin other than the ultraviolet curable resin.

[0020]

[Embodiment 3] FIGS. 4A and 4B are manufacturing process diagrams of a method for manufacturing a composite optical element according to this embodiment. Figure 4
(A) shows a state in which a resin layer 3 is formed by a biconcave optical glass substrate 2 having a radius of curvature of 60 mm and an outer diameter of 30 mm and a mold 1 having a molding surface 1a having a desired surface shape.
The method of using the bell holder 12 for positioning the spherical center 14 of the optical surface 2a on which the resin layer 3 is not formed and the optical axis 13 of the mold 1 is the same as that of the first embodiment.

In this state, the resin layer 3 is cured. Next, as shown in FIG. 4B, the outer periphery of the glass substrate 2 is processed into a desired shape by the grindstone 7 in the same manner as in Examples 1 and 2. At that time, by rotating the grindstone 7 and moving it in a direction parallel to the optical axis 13, the end polishing surface 7a formed on the grindstone 7 causes the end surface 2c of the glass base material 2 which is perpendicular to the optical axis 13 at the same time. To process. After that, the mold 1 and the resin layer 3
By releasing from the interface with and, a composite optical element having the same quality as in Examples 1 and 2 was obtained.

In the composite type optical element obtained in this example, since the outer peripheral portion of the glass substrate 2 does not have an acute angle portion, burrs (fine chips) generated by handling or the like are less likely to occur.

[0023]

[Embodiment 4] FIG. 5 shows a process chart of a method of manufacturing a composite optical element according to this embodiment. Until the contact molding 4 comprising the mold 1, the resin layer 3 and the glass substrate 2 is obtained,
Is the same as. A chamfered sloping portion 7b is formed on the grindstone 7 for processing the outer periphery of the glass base material 2, and a chamfered portion 2d is formed on the outer peripheral portion of the processed glass base material 2. The composite optical element obtained in this example had the same quality as in Examples 1 to 3 above.

In the above embodiments, the desired shape of the outer periphery of the glass substrate 2 is a cylindrical surface, an end surface, or a chamfered portion, but the present invention is not limited to such an embodiment, and as shown in FIG.
As shown in (b), it may be a V groove surface or a stepped surface.

As described above, according to the method for producing a composite optical element of the present invention, highly accurate positioning is performed when forming a contact molding comprising a mold, a resin layer and a glass substrate, and Since the outer periphery of the glass base material is centered before the contact molded body is released from the mold, it is possible to obtain a composite optical element which has no scratches on the optical surface, is inexpensive, and has no restriction on the shape of the glass base material. it can.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a manufacturing method of the present invention.

FIG. 2 is a manufacturing process diagram illustrating a method of manufacturing the composite optical element according to Example 1 of the present invention.

FIG. 3 is a manufacturing process diagram illustrating a method of manufacturing a composite optical element according to Example 2 of the present invention.

FIG. 4 is a manufacturing process diagram illustrating a method of manufacturing a composite optical element according to Example 3 of the present invention.

FIG. 5 is a process chart showing a method of manufacturing a composite optical element according to Example 4 of the present invention.

FIG. 6 is a main part front view showing a modified example of the outer peripheral shape of the glass substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold 2 Glass base material 3 Resin layer 4 Adhesive molding 6,13 Optical axis 7 Grinding stone (processing member) 11 UV curable resin 15 axis

Claims (1)

[Claims] 1. A method of manufacturing a composite optical element, wherein an energy-curable resin layer is formed on one surface of a glass material, the optical axis of which passes through the spherical center of the other surface of the glass substrate. In a method for manufacturing a composite optical element in which an optical functional surface is transferred to the resin by a mold, when the optical functional surface is transferred to the resin by the mold, the resin is brought into close contact with the mold and the mold and the resin. A method for producing a composite-type optical element, characterized in that the glass base material is formed as an integral contact molding, and the outer diameter of the glass base material is processed into a predetermined shape while maintaining the above-mentioned contact state.