JP5554193B2 - Lens unit and lens unit manufacturing method - Google Patents

Description

  The present invention relates to a lens unit and a method for manufacturing the lens unit.

  As shown in FIG. 8, in the conventional lens unit, a support body 111 is disposed around the lens portion 112, and the lens portion 112 can be attached to the distal end portion of the optical fiber 115. The lens portion 112 is formed of a thermosetting transparent resin such as a silicone resin.

JP 2004-271665 A

  The conventional lens unit has advantages such as superior heat resistance compared to thermoplastic resin because the lens portion 112 is formed of a thermosetting transparent resin such as silicone resin. However, when a thermosetting transparent resin such as a silicone resin is used for the lens portion 112, there is a problem that after the lens portion is molded, curing shrinkage of the resin occurs and it is difficult to obtain a desired shape of the lens portion.

The lens unit of the present invention includes a lens part, a frame that holds the lens part, and a plurality of connecting parts that extend from the lens part to the inside of the frame. The lens part and the connecting part are thermosetting. The lens unit is made of the same material, which is a transparent resin, and a film made of a part of the frame is formed on the surface of the lens part.

As a result, the lens unit of the present invention has a plurality of connecting portions that supply resin to the lens portion even if resin curing shrinkage occurs after the lens portion is molded. It is easy to be done. In addition, since the resin is surely filled in the film formed of a part of the frame, a desired shape of the lens portion is more easily obtained. Moreover, it is easy to maintain the shape of the lens portion even after the lens portion is formed.

Furthermore, the lens unit of the present invention is characterized in that the film is an antireflection structure. As a result, light loss on the surface of the lens portion can be reduced.

The lens unit of the present invention is characterized in that the thermosetting transparent resin is a silicone resin composition. This can reduce light loss in the wavelength region of 400 nm or more in the lens unit.

The lens unit of the present invention is characterized in that there are a plurality of lens units. Accordingly, since there is a connecting portion between the lens portion and the lens portion, it is easier to maintain the shape of the lens portion even after the lens portion is formed.

In the method of manufacturing a lens unit including the lens portion of the present invention, a frame that holds the lens portion, and a plurality of connecting portions that extend from the lens portion to the inside of the frame, the frame injects a transparent resin. And a first connection path connected to the lens part forming space corresponding to the lens part, and a second connection path connecting to the lens part forming space and overflowing the transparent resin. Is injected into the mold forming the lens part forming space from the first connecting path, and when the transparent resin is cured, the lens part forming space is heated, and the transparent resin in the lens part forming space starts to be cured. Then, the connecting portion is formed by curing the resin in the first connecting path and the second connecting path. With this, the lens unit manufacturing method according to the present invention can reduce the amount of cure and shrinkage of the transparent resin in the lens portion forming space from at least one of the first connection path and the second connection path. Since the lens portion is formed by supplying a cured transparent resin, the desired shape of the lens portion is easily obtained.

The lens unit manufacturing method of the present invention is characterized in that a film made of a part of the frame is provided between the lens part forming space and the mold. As a result, since the resin is surely filled in the film formed of a part of the frame, a desired shape of the lens portion is easily obtained. Moreover, it is easy to maintain the shape of the lens portion even after the lens portion is formed.

In the lens unit manufacturing method of the present invention, at least one of the first connection path and the second connection path is changed to cure the transparent resin in the lens portion forming space. It is characterized by compensating for the shrinkage. Accordingly, since the resin is surely filled in the lens part forming space, a desired shape of the lens part is more easily obtained.

Furthermore, in the method of manufacturing a lens unit according to the present invention, a plurality of lens units are connected in series, and the transparent resin is injected from the lens unit at one end of the group of connected lens units toward the lens unit at the other end, When molding a plurality of lens units sequentially, the lens units at the other end are sequentially cured. As a result, even when a plurality of lens units are molded simultaneously, the resin is surely filled into the lens part forming space, so that a desired shape of the lens part is more easily obtained.

  The lens unit and the lens unit manufacturing method according to the present invention have a plurality of connecting portions that supply resin to the lens portion even if the resin is cured and contracted after molding the lens portion. It is easy to get.

1 is a schematic plan view of a lens unit according to a first embodiment. It is a figure which shows the cross section of the lens unit of 1st Embodiment, and is a figure explaining the AA cross section of FIG. It is a figure which shows the modification of the lens unit of 1st Embodiment. It is a figure explaining the manufacturing method of the lens unit of 1st Embodiment. It is a figure which shows the modification of the manufacturing method of the lens unit of 1st Embodiment. It is a figure explaining the manufacturing method of the lens unit group which arranged the lens unit of 1st Embodiment in multiple numbers. It is a figure which shows the lens unit group which arranged the lens unit of 1st Embodiment in multiple numbers. It is a figure which shows the conventional lens unit.

  Next, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a schematic plan view of a lens unit for explaining a first embodiment of the present invention. FIG. 2 is a diagram illustrating a cross section of a lens unit for explaining the present embodiment, and is a diagram illustrating a cross section taken along the line AA of FIG. FIG. 3 is a diagram showing a modification of the present embodiment. Further, FIG. 4 is a diagram for explaining a manufacturing method of the lens unit of the present embodiment. FIG. 5 is a diagram showing a modification of the method for manufacturing the lens unit of the present embodiment, and FIG. 6 is a diagram for explaining a method of manufacturing a lens unit group in which a plurality of lens units of the present embodiment are connected. FIG. 7 is a diagram illustrating a lens unit group in which a plurality of lens units according to this embodiment are connected.

FIG. 1 is a schematic plan view of the lens unit of the present embodiment. As shown in FIG. 1, the lens unit 1 according to the present embodiment includes a circular lens portion 2 having a diameter of about 500 μm, a frame 4 that holds the lens portion 2, and a connecting portion 5. The connecting portion 5 is a lens portion. It consists of two supports extending from 2 to the inside of the frame 4. The lens portion 2 and the connecting portion 5 are made of a silicone resin that is a thermosetting transparent resin, and the frame 4 is made of an adamantane resin.

FIG. 2 is a diagram showing a cross section taken along the line AA of the lens unit shown in FIG. As shown in FIG. 2, a film 7 made of a part of the frame 4 is formed on the surface of the lens unit 2. The thickness of the film 7 is as thin as about 10 μm and does not affect the optical characteristics of the lens portion 2 in the wavelength region from the far infrared region to 400 nm. In the lens unit 1 of the present embodiment, about 3% of the resin is cured and contracted after forming the lens part 2, but there are two connecting parts 5 that supply the resin to the lens part 2. Since the resin is filled in 2, the desired shape of the lens unit 2 is easily obtained. Furthermore, since the connection part 5 extended from the lens part 2 is provided in the inside of the frame 4, the positional accuracy of the lens part 2 with respect to the frame 4 can be maintained. Further, the lens unit 1 of the present embodiment has the film 7 formed of a part of the frame 4 formed on the surface of the lens portion 2, so that the resin is surely filled. The desired shape of 2 is more easily obtained. Furthermore, since the lens unit 2 is held by the film 7 even after the lens unit is formed, the shape of the lens unit 2 can be easily maintained.

In the embodiment of the present invention, the case where the film 7 formed of a part of the frame 4 has a constant film thickness is exemplified. May be an antireflection structure having about 600 nm, and light reflection loss on the surface of the lens portion 2 can be reduced. In the present embodiment, the case where the lens unit 2 is a convex lens is illustrated, but a concave lens or the like may be used.

FIG. 3 is a diagram showing a modification of the present embodiment. As shown in FIG. 3, since the surface of the lens portion 2 does not have the film 7 made of a part of the frame 4, the light loss on the surface of the lens portion 2 is less than that of the structure shown in FIG. can do. In addition, for the frame 4, a wide range of materials such as metal can be selected.

  Next, a method for manufacturing the lens unit according to this embodiment will be described.

FIG. 4 is a view for explaining a method of manufacturing the lens unit according to this embodiment. FIG. 4A is a diagram showing a frame forming process. As shown in FIG. 4A, an adamantane resin serving as a frame is injected into the space between the outer mold 9 and the inner mold 8, and the outer mold 9 and the inner mold 8 are heated to 150 ° C. and cured.

FIG. 4B is a view for explaining the inner mold removing step. As shown in FIG. 4B, the frame 4 is left on the outer mold 9 and only the inner mold 8 is removed. The frame 4 has a first connecting path 11 connected to an injection hole (not shown) for injecting a silicone resin, which is a thermosetting transparent resin, and a lens part forming space 10 corresponding to the lens part. It has the 2nd connection path 12 connected with the formation space 10 and overflowing a silicone resin.

FIG. 4C is a diagram showing a lens part forming step. As shown in FIG. 4C, silicone resin is injected from the first connecting path 11 into the lens portion forming space 10 and overflows into the second connecting path 12. After injecting the silicone resin, the outer mold 9 is heated to 150 ° C. At this time, there is only a thin film 7 consisting of a part of the frame 4 between the lens part forming space 10 and the outer mold 9, and heat transfer from the outer mold 9 is good. Curing of the resin is started before the silicone resin in the first connection path 11 and the second connection path 12. Next, the resin in the first connection path 11 and the second connection path 12 is cured. Accordingly, in the method for manufacturing a lens unit according to the present invention, the curing shrinkage of the silicone resin in the lens portion forming space 10 is uncured from at least one of the first connection path 11 and the second connection path 12. It is easy to obtain a desired shape that accurately reflects the shape of the lens portion forming space 10 by supplying the silicone resin. Next, the uncured silicone resin in the first connection path 11 and the second connection path 12 is cured by heating.

FIG. 4D is a diagram showing an outer mold removing process. After the silicone resin is cured, as shown in FIG. 4 (d), the outer mold 9 can be removed to obtain the lens unit 1 shown in FIG. In the present embodiment, the case where the film 7 made of a part of the frame 4 is provided between the lens part forming space 10 and the outer mold 9 is illustrated as an example. Even so, the manufacturing method is the same, and since there is no film 7 consisting of a part of the frame 4 between the lens part forming space 10 and the outer mold 9, there is little heat transfer loss due to the film 7, Curing of the silicone resin in the lens portion forming space 10 is started earlier than the silicone resin in the first connection path 11 and the second connection path 12.

FIG. 5 is a diagram showing a modification of the method for manufacturing the lens unit of the present embodiment. As shown in FIG. 5, the first connecting path 11 and the second connecting path 12 are provided with a diaphragm portion 14 for changing the volume, and the cured shrinkage of the silicone resin in the lens portion forming space 10 is determined as the diaphragm. It can be compensated by deformation of the portion 14. As a result, the lens portion forming space 10 is more reliably filled with resin, so that the desired shape of the lens portion can be obtained more easily.

FIG. 6 is a diagram for explaining a method of manufacturing a lens unit group in which a plurality of lens units according to the present embodiment are arranged in series. As shown in FIG. 6, a plurality of lens units are connected in series, and silicone resin is injected from the lens unit 1 </ b> B at one end of the connected lens unit group toward the lens unit 1 </ b> A at the other end. The outer mold 19 forming the lens unit 1A and the lens unit 1B is provided with an injection hole 15 for injecting a silicone resin, and the injection hole 15 is connected to the first connection path 11 of the lens unit 1B. When molding a plurality of lens units sequentially, the lens unit 1A at the other end is heated first and cured sequentially. As a result, even when a plurality of lens units are simultaneously molded, the resin is surely filled into the lens portion forming space, so that the desired shape of the lens portion is more easily obtained.

FIG. 7 is a diagram illustrating a lens unit group in which a plurality of lens units according to the present embodiment are arranged. As shown in FIG. 7, in the lens unit group of the present embodiment, the lens unit 1A and the lens unit 1B are connected to each other by the frame 4, so that the mutual crosstalk between the lens units is reduced between the frame 4 and the lens. Compared with the case where the part 2 is formed of the same optical member, it can be remarkably reduced.

DESCRIPTION OF SYMBOLS 1, 1A, 1B Lens unit 2 Lens part 4 Frame 5 Connection part 7 Film | membrane 8 Inner type | mold 9, 19 Outer type | mold 10 Lens part formation space 11 1st connection path 12 2nd connection path 14 Diaphragm part 15 Injection hole

Claims (8)

It consists of a lens part, a frame for holding the lens part, and a plurality of connecting parts extending from the lens part to the inside of the frame, and the lens part and the connecting part are made of a thermosetting transparent resin. A lens unit comprising: a film made of a part of the frame formed on a surface of the lens unit. The lens unit according to claim 1, wherein the film is an antireflection structure . The lens unit according to claim 1 or 2, wherein the thermosetting transparent resin is a silicone resin composition . The lens unit according to any one of claims 1 to 3, wherein the lens unit is a lens unit.
A lens unit characterized by having a plurality of lenses. In the manufacturing method of manufacturing a lens unit including a lens unit, a frame for holding the lens unit, and a plurality of connecting units extending from the lens unit to the inside of the frame, the frame has an injection hole for injecting a transparent resin. And a first connecting path that connects to the lens part forming space corresponding to the lens part, and a second connecting path that connects to the lens part forming space and overflows the transparent resin. When the transparent resin is cured by injecting into the mold forming the lens part forming space from one connecting path, the lens part forming space is heated, and the transparent resin in the lens part forming space starts to be cured, A method of manufacturing a lens unit, comprising: forming a connecting portion by curing the resin in the first connecting path and the second connecting path. 6. The method of manufacturing a lens unit according to claim 5, wherein a film made of a part of the frame is provided between the lens part forming space and the mold. A manufacturing method of a lens unit. 7. The lens unit manufacturing method according to claim 5, wherein at least one of the first connection path and the second connection path is changed to change the lens unit forming space. A method of manufacturing a lens unit , comprising: compensating for the curing shrinkage of the transparent resin . A method for manufacturing a lens unit according to any one of claims 5 to 7, comprising:
When the plurality of lens units are connected in series, the transparent resin is injected from the lens unit at one end of the group of connected lens units toward the lens unit at the other end, and when the plurality of lens units are sequentially molded, the other A method of manufacturing a lens unit, wherein the lens unit is sequentially cured from the end lens unit .

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