JP2010145603A - Hybrid lens and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hybrid lens and a method of manufacturing it. <P>SOLUTION: This hybrid lens 100 includes a lens substrate 110 made of glass material, and at least one plastic layer 120 that covers the lens substrate and is made of a transparent plastic material. At least one plastic layer 120 includes a reference surface 1231. This method of manufacturing the hybrid lens includes (1) a step of fixing the lens substrate in a molding cavity of a die and having a surface molding section on a cavity wall of the molding cavity, (2) a step of forming the plastic layer that is stuck to the lens substrate and has the reference surface by injecting transparent plastic material of a flowing state from an injection port into the molding cavity and solidifying the transparent plastic material, and (3) a step of taking out the hybrid lens by opening the die. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to lens technology, and more particularly to a hybrid lens and a method for manufacturing the same.

  In recent years, as the communication bandwidth of personal mobile devices has increased, the storage capacity has increased significantly, and the unit price has decreased, not only has the ratio of adding imaging function modules to mobile devices increased rapidly, but also low resolution ( 300,000 pixels) to high resolution (1 million pixels). To meet the demands of high resolution, low cost, small volume and mass production of small imaging lenses, in addition to using conventional plastic lenses and imitation glass lenses, to develop a hybrid lens including a lens base (Hybrid lens) Is also an item of development.

  In consideration of the requirements of both small volume and low cost, in order to provide high-quality image quality, it is necessary to satisfy the above requirements with a relatively small number of lenses using an aspheric lens. Most of this is achieved by using all-plastic lenses by optical-grade plastic injection molding, and some by using all-glass lenses that are imitation-molded. A hybrid lens is a lens member that is between an all plastic lens and an all glass lens in terms of manufacturing cost and quality. Referring to FIG. 1, a conventional hybrid lens 100 ′ employs a glass flat plate as a lens base 110 ′, and a transparent plastic layer 120 ′ is added on the entrance surface (or the exit surface) of the lens base 110 ′. This constitutes an aspherical interface necessary for optical image formation. The hybrid lens 100 ′ is provided with a reference surface 111 ′ used for assembly and positioning at the periphery of the lens base 110 ′.

  Compared to the primary molding of all plastic lenses, the manufacturing process of the hybrid lens is a multi-stage manufacturing process in which a plastic material is further added to the lens base, so the cost is relatively high, but the glass material occupies most of the volume. Therefore, the entire hybrid lens has relatively good material homogeneity and environmental resistance compared to all plastic lenses. On the other hand, an all-glass aspherical lens has the best optical quality and stability of use, but adopts a high-temperature imitation manufacturing process, which increases the manufacturing cost. Although the hybrid lens is slightly inferior, but has optical quality and environmental resistance close to that, the manufacturing process is simple and the manufacturing cost is relatively low.

Many patents have already been applied for because hybrid lenses have the advantage of both quality and manufacturing costs. For example, Japanese Patent No. 3926380, Japanese Patent No. 3946245, and Japanese Patent No. 3976780. The main claim is a cemented hybrid lens having a positive refractive index, which is composed of a first lens, a second lens, and a third lens from the object side to the image side. The first lens and the third lens are cured. The second lens is formed of an optical glass material having a high softening temperature, the first lens and the second lens are bonded with an adhesive or directly, and the second lens and the third lens are bonded with an adhesive. Or it adhere | attaches directly and the following formula | equation 1 is satisfy | filled.
_{0 ≦ | N 3 -N 2 |} ≦ 0.1,0 ≦ | N 3 -N 4 | ≦ 0.1,0 ≦ | ν 3 -ν 2 | ≦ 30,0 ≦ | ν 3 -ν 4 | ≦ 30

  N2, N3, and N4 are the refractive indexes of the first lens, the second lens, and the third lens, respectively, and ν2, ν3, and ν4 are the Abbe numbers of the first lens, the second lens, and the third lens, respectively.

The surface shapes of the first lens, the second lens, and the third lens in the Japanese patent are the expressions of the adhesion between the first lens and the second lens, the adhesion between the second lens and the third lens, and the configuration of the positive refraction lens. Can be a convex surface, a flat surface, and a concave surface, and a plurality of combinations of the lenses (first lens, second lens, and third lens) may be used.
Japanese Patent No. 3926380 Japanese Patent No. 3946245 Japanese Patent No. 3976780

  In the Japanese patent, the first lens and the third lens are plastic layers made of a curable resin, the material of which may be replaced with another transparent plastic material, and the second lens is a lens base made of a glass material. In realization on a small high-precision lens, the eccentric positioning of the lens usually depends on the fit of the lens base and the clamping mechanism, which is rugged and stable inside, and therefore requires very precise tolerances regarding the geometric size of the lens base. Taking a high resolution mobile phone imaging module as an example, the decentration accuracy requirement of the lens is within +/− 3 μm, and the deviation that limits the appearance size of this lens base must be within +/− 3 μm. However, considering that it is necessary to use thin glass as a material in small high-precision lens applications, this lens base is not easy to manufacture by mass production, and therefore the manufacturing cost of this type of hybrid lens is low. The problem arises that it becomes high and the yield decreases.

  An object of the present invention is to provide a hybrid lens having a simple manufacturing process and a low cost, and a method for manufacturing the hybrid lens, with respect to the above-described drawbacks existing in the current technology.

  To achieve the above object, the hybrid lens provided by the present invention includes a lens base made of a glass material, and at least one plastic layer covering the lens base and made of a transparent plastic material, and at least one plastic. A reference plane is provided in the layer.

The method for manufacturing a hybrid lens provided by the present invention includes:
(1) fixing the lens base in the mold cavity of the mold, and having a surface molding part on the cavity wall of the mold cavity;
(2) Injecting a transparent plastic material in a fluid state from the injection hole into the molding cavity, solidifying the plastic material, and forming a plastic layer attached to the lens substrate and having a reference surface;
(3) opening the mold and taking out the hybrid lens.

  In the hybrid lens of the present invention, the reference surface is provided on the plastic layer. Therefore, when the hybrid lens is manufactured, it can be directly generated in the process of molding the plastic layer on the lens base, so that the manufacturing process can be simplified. Cost can be reduced and yield can be improved.

  In order to describe in detail the technical contents, structural features, objects and effects to be achieved of the present invention, examples will be given below and described with reference to the drawings.

  Referring to FIG. 2, the first embodiment of the present invention includes a lens base 110 and a plastic layer 120, and the plastic layer 120 includes an entrance surface covering portion 121 that covers the entrance surface of the lens base 110, and a lens base exit surface. The peripheral surface of the peripheral surface covering portion 123 is provided with a reference surface 1231 for attachment, and is provided on the peripheral surface of the lens peripheral surface portion 123. Is provided with a concave groove 1232.

  3 may be used for manufacturing the hybrid lens 100 of the present invention. The mold includes a first mold 210 and a second mold 220. The first mold 210 includes a first mold 210 and a second mold 220. The cavity 211 is provided, the cavity wall of the first cavity 211 is further provided with a surface molding portion 2111, the injection hole 212 is provided in the cavity wall of the first cavity 211, and is convex on the cavity wall of the first cavity 211. There are three base clamping blocks 213 that extend. The second mold 220 is provided with a second cavity 221, and there are three base body clamping blocks 222 extending in a convex shape on the cavity wall of the second cavity 221. When the hybrid lens 100 is manufactured with a mold, the base body clamping blocks 213 and 222 are fixed inside, the lens base 110 is first fixed, and the molds are aligned, and then the first cavity 211 and the second cavity 221 are formed into a molding cavity. 240, and a transparent heat-set plastic material is injected from the injection hole 212 so as to fill the molding cavity 240 and cover all or part of the lens base 110, and further heat the mold to heat-set. When the plastic material 120 is cured to form the plastic layer 120 and the first mold 210 and the second mold 220 are separated after completion, the hybrid lens 100 covering the lens base 110 as shown in FIG. 2 is obtained.

  In the case of using a mold that can transmit ultraviolet light in this design, an ultraviolet-cured transparent plastic material can be used instead.

  Referring to FIG. 4, the second embodiment of the hybrid lens 300 of the present invention includes a lens base 310, a first plastic layer 320, and a second plastic layer 330, and the first plastic layer 320 is an incident surface of the lens base 310. The second plastic layer 330 has an exit surface covering portion 332 that covers the exit surface of the lens base 310 and a peripheral cover portion 331 that covers the periphery of the lens base. A surface 3311 is formed.

  5 and 6, when the hybrid lens 300 is manufactured, a mold 400 as shown in FIG. 5 and a mold 500 as shown in FIG. 6 can be employed. The mold 400 has a molding cavity 420 and an injection hole 410 communicating with the molding cavity 420. After making the lens base 310 a part of the mold 400, a transparent plastic material is injected from the injection hole 410 of the mold 400 to fill the molding cavity 420 of the mold 400 with the transparent plastic material, and further, ultraviolet rays are applied to the lens base 310. Injecting from the surface, the injected transparent plastic material is cured to form the left incident surface coating portion 320, and then the half-molded hybrid lens is taken out from the mold 400 and further fixed in the mold 500. A surface molding part 521 is provided on the molding cavity 520 of the mold 500, and a transparent plastic material is injected from the injection hole 510 of the mold 500 to fill the molding cavity 520 of the mold 500. The transparent plastic material injected by injecting ultraviolet rays from 320 is cured to form the right exit surface covering portion 330. After completion, when the mold 500 is removed, the lens substrate 3 as shown in FIG. Hybrid lens 300 covering the 0 is obtained.

  The plastic layer of the hybrid lens of the present invention is not limited to the one completely covering the lens base, and the one having a visible structural shape may be partially exposed to the outside according to the manufacturing needs. It may be what you are doing. The main entrance surface and exit surface of the hybrid lens may be any one or a combination of a plane, a spherical surface, an aspherical surface, a free-form surface, and a Fresnel surface.

  In the method for producing a hybrid lens of the present invention, the transparent plastic material may be a chemically solidified material, a heat solidified material, an ultraviolet solidified material, or the like.

  In the hybrid lens of the present invention, the reference surface is provided on the plastic layer. Therefore, when the hybrid lens is manufactured, it can be directly generated in the process of molding the plastic layer on the lens base, so that the manufacturing process can be simplified. Cost can be reduced and yield can be improved.

It is the schematic of a well-known hybrid lens. It is sectional drawing of one Example of the hybrid lens of this invention. FIG. 3 is a schematic view when a lens base is installed in a mold in the manufacturing process of the hybrid lens shown in FIG. 2. It is sectional drawing of the 2nd Example of the hybrid lens of this invention. FIG. 5 is a cross-sectional view of one state in the manufacturing process of the hybrid lens shown in FIG. 4. It is sectional drawing of another state in the manufacture process of the hybrid lens shown by FIG.

Explanation of symbols

100 'hybrid lens 110' lens base 120 'plastic layer 111' reference surface 100 hybrid lens 110 lens base 120 plastic layer 121 entrance surface covering portion 122 exit surface covering portion 123 peripheral surface covering portion 1231 reference surface 1232 concave groove 210 first mold 220 Second mold 213 Substrate clamping block 222 Substrate clamping block 240 Molding cavity 211 First cavity 2111 Surface molding part 221 Second cavity 212 Injection hole 300 Hybrid lens 310 Lens substrate 320 First plastic layer 330 Second plastic layer 332 Outgoing surface coating part 331 Perimeter covering portion 3311 Reference surface 400 Mold 500 Mold 420 Molding cavity 520 Molding cavity 410 Injection hole 510 Injection hole 521 Surface molding part

Claims (9)

A lens base made of a glass material;
At least one plastic layer that covers the lens substrate and is made of a transparent plastic material, and at least one plastic layer is provided with a reference surface.
Hybrid lens.   There is one plastic layer, and the plastic layer includes an incident surface covering portion that covers the incident surface of the lens base, an exit surface covering portion that covers the exit surface of the lens base, and a peripheral covering portion that covers the periphery of the lens base. The hybrid lens according to claim 1, wherein the reference surface is formed on a peripheral edge of the peripheral edge covering portion, and at least one concave groove is provided on the peripheral edge covering portion.   The plastic layer may further comprise a first plastic layer and a second plastic layer, the first plastic layer covers the entrance surface of the lens substrate, and the second plastic layer covers the exit surface of the lens substrate. The hybrid lens according to claim 1, further comprising a peripheral portion and a peripheral covering portion that covers a peripheral edge of the lens base, wherein the reference surface is formed on the peripheral edge of the peripheral covering portion.   The hybrid lens according to claim 2, wherein a reference surface of the peripheral covering portion has a cylindrical shape.   The hybrid lens according to claim 2, wherein a structure shape of the entrance surface and the exit surface may be a flat surface, a spherical surface, an aspherical surface, or a free-form surface. (1) a step of fixing the lens substrate in a molding cavity of the mold, the mold cavity having a surface molding portion on the cavity wall, and an injection hole provided on the mold;
(2) injecting a fluidized transparent plastic material from the injection hole into the molding cavity, solidifying the transparent plastic material, and forming a plastic layer attached to the lens substrate and having a reference surface;
(3) A method of manufacturing a hybrid lens, comprising: opening a mold and taking out the hybrid lens.   The mold includes a first mold and a second mold, the first mold is provided with a first cavity, the cavity wall of the first cavity has a surface molding portion, and is convex on the cavity wall of the first cavity. There is at least one base block extending in the cavity, the injection hole is provided in the cavity wall of the first cavity, the second cavity is provided in the second mold, and extends at least in a convex shape on the cavity wall of the second cavity. There is one base block, the second cavity and the first cavity communicate with each other and form the molding cavity, and the lens base is sandwiched and fixed between the first type base block and the second type base block. The method for manufacturing a hybrid lens according to claim 6, wherein the cavity wall of the first cavity and the cavity wall of the second cavity are separated by a certain distance.   The method for manufacturing a hybrid lens according to claim 6, wherein an incident surface covering portion is attached to the lens base, and the lens base is fixed in the molding cavity by fixing the incident surface covering portion on the mold. . The method for manufacturing a hybrid lens according to claim 6, wherein the transparent plastic material may be a chemically solidified material, a heat-solidified material, or an ultraviolet-cured material.