JP2013202810A - Composite molded lens, die for composite molded lens, and method of manufacturing composite molded lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a composite molded lens in which adhesiveness of a joined surface is enhanced in molding the composite molded lens having a frame body thicker than an outer peripheral part of a lens part by continuously carrying out compression molding and injection molding.SOLUTION: In a composite molded lens 10, a lens body 11 formed of a lens part 12 and a first flange part 13 formed so as to surround the lens part 12 is compression-molded. Then, resin such as PMMA and PC is injected, and a frame body 14, which is formed of a frame part 15 formed so as to surround the first flange part 13, and a second flange part 16 integrally formed on an inner diameter side of the frame part 15 and adjacent in an optical axis direction of the first flange part 13, is formed. The second flange part 16 is tightly joined to the first flange part 13 and is solidly joined by injection molding. An outer peripheral end surface 18 of the first flange part 13 is crushed until it protrudes in a frame part forming space to form a joined surface with the frame part 15.

Description

  The present invention relates to a composite molded lens formed by continuously performing compression molding and injection molding, a mold for a composite molded lens, and a method for manufacturing a composite molded lens.

  Optical lenses used in digital cameras, projectors, camera-equipped mobile terminal devices, etc., may be compression molded lenses that have high optical performance and do not require post-processing such as polishing. It is difficult to form an outer peripheral surface for optical axis alignment. For this reason, there has been proposed one in which a ring-shaped flange portion is injection-molded on the outer peripheral portion of the lens, and a lens frame or a lens frame is formed by extending the flange portion. Patent Documents 1 and 2 below describe a lens unit in which a lens frame is injection-molded around the outer periphery of a compression-molded lens. Examples of the portable terminal device include a mobile phone, a smartphone, a portable game machine, and a PDA (Personal / Digital / Assistant).

Japanese Patent No. 2502718 JP 2007-22905 A

  In recent years, as lenses have become smaller and larger in diameter, the tendency to be thinner than the outer diameter has become stronger. In particular, in the case of a convex lens, when the thickness is reduced, the outer peripheral portion of the lens becomes extremely thin, and it is difficult to ensure a sufficient width dimension of the end surface. Therefore, a ring-shaped flange portion is integrally formed on the outer periphery of the convex lens by injection molding. However, if the adhesion between the outer peripheral portion of the convex lens and the joint surface of the flange portion is not sufficient, an expansion difference due to a change in environmental temperature or The joint surface may be peeled off due to twisting or the like during assembly to the lens barrel.

  In view of the above-described problems, the present invention has a bonding surface having a close adhesion when molding a composite molded lens having a flange portion (frame body) thicker than the outer peripheral portion of the lens portion by continuously performing compression molding and injection molding. An object is to form a reinforced composite molded lens.

  The compound molded lens according to the present invention is a compound molded lens in which a press-molded lens body and a frame surrounding the lens body are integrated by injection molding, and the lens body includes a lens portion having an optical surface and the lens portion. The frame is formed integrally with the frame portion formed so as to surround the first flange portion and the inner diameter side of the frame portion, and the optical axis of the first flange portion is formed. It consists of the 2nd collar part adjacent to a direction, The 1st collar part and the 2nd collar part overlapped in the optical axis direction, and it was characterized by the above-mentioned.

  The second collar is preferably formed by injection so as to sandwich the first collar from the front and rear of the first collar in the optical axis direction. The lens body has a cylindrical surface between the outer periphery of the lens part and the outer periphery of the first flange part, the dimension of which is larger than the thickness dimension of the inner peripheral end of the second flange part on one surface of the first flange part. You may make it form adjacent. It is preferable that at least one surface of the lens portion does not protrude from the frame body in the optical axis direction.

The mold for a composite molded lens according to the present invention is a method in which a preform is pressed between an upper mold and a lower mold to mold a lens body including a lens portion having an optical surface and a first flange portion surrounding the outer periphery thereof. A frame body integrally formed on the inner diameter side of the frame portion formed so that the second flange portion adjacent to the optical axis direction of the first flange portion and the outer peripheral side being connected to the frame body surrounds the first flange portion. A mold for a composite molded lens integrated by injection molding, wherein at least one of the upper mold and the lower mold is
A lens core for compression molding the lens portion, and a first flange that is compressed and molded and then moved in a direction opposite to the press direction of the preform and adjacent to one surface of the first flange in the optical axis direction. It is characterized by comprising a collar core for forming a collar part molding space, and a frame core having a frame molding space for holding the collar core movably in the press direction and forming a frame part. To do.

  The upper mold and the lower mold include a lens part core, a collar part core, and a frame part core, and each may be independently movable. The frame part forming space may be formed across the upper mold and the lower mold. In the upper mold, the lens part core and the collar part core are integrally formed so that the collar part forming surface of the collar part core that presses the preform protrudes from the outer peripheral end of the lens part core. A cylindrical surface having a dimension in the optical axis direction larger than a thickness dimension of the inner peripheral end of the second collar portion may be formed inside the surface.

  A method of manufacturing a composite molded lens according to the present invention is a method of manufacturing a composite molded lens in which a press-molded lens body and a frame surrounding the lens body are integrated by injection molding, and a preform of an optical material is formed. A first step of placing between the upper die and the lower die, a second step of pressing the preform to form a lens body having a first collar on the outside of the optical surface, and compression molding the first collar A third step of forming the second collar forming space adjacent to one surface of the first collar part in the optical axis direction by moving the collar part for the collar part in the direction opposite to the press direction of the preform; The fourth step of sequentially injecting molten resin into the flange forming space and the frame forming space formed on the outer peripheral side thereof to form a frame body composed of the second flange portion and the frame portion is sequentially performed. It is characterized by.

  According to the present invention, a wide joint surface is obtained by injection molding a frame body having a second flange portion that is tightly bonded to the first flange portion of the lens body to be compression-molded, and is firmly integrated. Composite molded lenses can be made.

It is a top view of the compound molded lens by this invention. It is sectional drawing of FIG. It is a flowchart which shows the shaping | molding procedure of a composite shaping lens. 1 is a cross-sectional view of a mold for a composite molded lens according to the present invention. It is a top view when seeing an upper model from the lower part. It is a figure when a lens body is compression-molded in FIG. It is a figure when the core for hips is returned in FIG. 6, and the 2nd collar part formation space is formed. FIG. 8 is a view when injection molding is performed in FIG. 7. It is sectional drawing of the composite molded lens when it is made not to make a level | step difference in a collar part. It is a figure explaining the metal mold | die which shape | molds the lens of FIG. It is a figure when compression-molding in FIG. It is a figure when the 2nd collar part shaping | molding space is formed by returning the collar part core in FIG. It is a figure explaining the metal mold | die which made the core for lens parts, and the core for collar parts into one. It is a figure when compression-molding in FIG. It is a figure when the core for lens bodies is returned in FIG. 14, and the 2nd collar part shaping | molding space is formed. It is sectional drawing for description of the metal mold | die in another embodiment. It is a figure when compression-molding in FIG. FIG. 18 is a view when the second collar part forming space is formed by returning the collar part core in FIG. 17. It is sectional drawing of the composite shaping | molding lens by the metal mold | die of FIG.

  As shown in FIGS. 1 and 2, a composite molded lens 10 according to the present invention surrounds a lens portion 12 having an optical surface formed by compression molding a plastic preform 30 (see FIG. 4), and the lens portion 12. The lens body 11 composed of the first flange portion 13 formed as described above, the frame portion 15 formed so as to surround the first flange portion 13 by injecting a resin such as PMMA or PC, and the inner diameter side of the frame portion 15 And a frame 14 formed of a second flange 16 adjacent to the first flange 13 in the optical axis direction. The second flange 16 is tightly bonded to the first flange 13 by injection molding and is firmly bonded. In addition, one optical surface 17 of the lens unit 12 may be formed so as not to protrude from the frame body 14 in a direction parallel to the optical axis 46. When the optical surface 17 is placed on a flat surface after molding, the optical surface 17 is formed. Does not touch and does not get scratched.

  The outer peripheral end face 18 of the first flange 13 is formed into a free-form surface such as the outer diameter side of the toroid when the preform 30 is crushed and spread. The preform 30 may be crushed until the outer peripheral end face 18 protrudes into the frame portion forming space 25 (see FIG. 6), but may be a little before the frame portion forming space 25. The outer peripheral end surface 18 is a joint surface between the first flange portion 13 and the frame portion 15. Note that the gate portion 19 formed when the frame portion 15 is injection-molded may be deleted as necessary.

  Next, a method for manufacturing the composite molded lens 10 according to the present invention will be described with reference to the flow shown in FIG. 3, and a composite molded lens mold 20 used therefor will be described.

  As shown in FIG. 4, the composite molded lens mold 20 includes an upper mold 21 and a lower mold 31. The preform 30 placed on the lower mold 31 is heated and softened (first step) to form the upper mold 21. Is pressed in a direction parallel to the optical axis 46. The upper die 21 has a lens part core 22 that presses the lens part 12, a collar part core 23 that presses the first flange part 13, and a frame part core that has a frame part forming space 25 that forms the frame part 15. 24, the lens core 22 is guided by the collar core 23, and the collar core 23 is guided by the frame core 24 so as to be movable in the pressing direction of the preform 30. The collar portion forming surface 33 provided on the lower surface of the collar portion core 23 is positioned without a step between the outer peripheral end of the lens portion forming surface 32 provided on the lower surface of the lens portion core 22.

  As shown in FIG. 5, the upper mold 21 has a lens part forming surface 32 including an optical surface on one surface of the lens part 12, a collar part forming surface 33 that forms the first collar part 13, and a frame part molding space 25. The formed frame core 24 is formed concentrically, and a gate 29 is provided on the outer peripheral side of the frame core molding space 25 from which the resin forming the frame 15 is injected. The lower mold 31 is formed with a transfer surface 36 that forms an optical surface on the other surface of the lens portion 12.

  As shown in FIG. 6, the preform 30 pressed by the lens part core 22 and the collar part core 23 is extended between the collar part forming surface 33 and the lower mold 31, and the first collar part 13. The outer peripheral end face 18 is crushed until it slightly protrudes into the frame forming space 25 (second step).

  As shown in FIG. 7, after the first collar 13 is compression-molded, the collar core 23 is moved in the direction opposite to the pressing direction (the direction indicated by the arrow 37), and the collar forming surface 33 is moved to the first. A second collar forming space 26 is formed that is separated from one surface of the collar 13 and is adjacent in a direction parallel to the optical axis 46. The second flange forming space 26 is formed on the inner diameter side of the frame forming space 25 (third step).

  As shown in FIG. 8, when the lens body 11 is formed and the second collar part molding space 26 is formed above the first collar part 13, the upper mold 21 and the lower mold 31 are not opened, and are melted from the gate 29. The molded resin is injected to form the frame body 14 including the frame portion 15 and the second flange portion 16 (fourth step). Thus, the lens body 11 formed by compression molding and the frame portion 15 formed by injection molding are joined significantly compared to the case where the outer peripheral end surface 18 of the first flange 13 and the frame portion 15 are joined. Even if there is a difference in expansion of the lens body 11 and the frame portion 15 due to a change in environmental temperature due to an increase in force, the lens body 11 and the frame portion 15 will not be separated, and will not be separated due to stress incorporated in the lens frame or the like.

  The composite molded lens 10 shown in FIG. 2 has a step between the lens portion 12 and the second flange portion 16, but like the composite molded lens 40 shown in FIG. 9, the lens portion 42 and the second flange portion 44. It is also possible to prevent a step between the two.

  As shown in FIG. 10, the collar core 23 protrudes downward from the lens core 22 so that a cylindrical step 38 is formed between the lens formation surface 32 and the collar formation surface 33. When the preform 30 is pressed after positioning, the thickness of the first flange 43 of the compression molded lens body 41 is made thinner than the outer peripheral end of the lens portion 42 as shown in FIG. Thereafter, the collar core 23 is returned to the position shown in FIG. 12 to form the second collar molding space 26, and then the resin melted from the gate 29 is added to the frame molding space 25 and the second collar molding space 26. To ejaculate. The thickness at which the first collar portion 43 and the second collar portion 44 are overlapped is the same as the thickness of the outer peripheral end of the lens portion 42, and no step is generated between the lens portion 42 and the second collar portion 44.

  Next, another embodiment according to the present invention will be described. However, the same components as those described in the above embodiments will be denoted by the same reference numerals, and description thereof will be omitted.

  As shown in FIG. 13, the composite molded lens mold 50 includes an upper mold 51 and a lower mold 31 that include a lens body core 52 having a lens portion forming surface 53 and a flange portion forming surface 54 and a frame portion core 24. It consists of. A cylindrical step 55 is provided between the flange forming surface 54 formed on the lower surface of the lens body core 52 and the outer peripheral end of the lens portion forming surface 53.

  As shown in FIG. 14, the preform 30 (first process) placed on the lower mold 31 is pressed by the lens body core 52 to form the lens portion 62 and the first flange portion 63 of the lens body 61. The The lens body 61 has a cylindrical surface 65 in which the dimension in the optical axis direction is larger between the outer periphery of the lens part 62 and the outer periphery of the first flange part 63 than the thickness dimension of the inner peripheral end of the second flange part to be formed later. (See FIG. 15) is formed adjacent to one surface of the first flange 63 by the step 55. The outer peripheral end face 64 of the first collar 63 extends between the collar forming surface 54 and the lower mold 31 and slightly protrudes into the frame molding space 25 (second process).

  As shown in FIG. 15, the lens body core 52 is compressed in the lens body 61 and then moved in the direction opposite to the pressing direction (the direction indicated by the arrow 37), and the flange forming surface 54 and the first flange 63. A second collar forming space 56 is formed between them (third step). The amount of movement of the lens body core 52 at this time must be within a range in which the step 55 is not separated from the cylindrical surface 65. If it moves beyond the level | step difference 55, the molten resin inject | poured into the 2nd collar part molding space 56 will wrap around in the space 57 which arose in the lens part 62, and a malfunction will arise. Accordingly, the dimension in the optical axis direction of the second collar part forming space 56 (the thickness dimension of the second collar part) is smaller than the cylindrical surface 65. The lens body core 52 is formed by combining the lens core and the collar core into one, but the lens core and the collar core are separately formed and then integrated. May be.

  Next, an example in which the above embodiment is adopted not only for the upper die but also for the lower die will be described.

  As shown in FIGS. 16 and 17, the composite molded lens mold 70 includes an upper mold 21 including a lens part core 22, a collar part core 23, and a frame part core 24, a lens part core 72, and the like. The lower mold 71 includes a collar core 73 and a frame core 74. The preform 30 pressed between the upper mold 21 and the lower mold 71 is extended between the collar forming surface 33 of the collar core 23 and the collar forming surface 78 of the collar core 73, and the outer peripheral end surface 18. Is crushed until it slightly protrudes into the frame forming space 75 formed across the frame cores 24 and 74 (second step).

  As shown in FIG. 18, after the first collar portion 13 is compression-molded, the collar cores 23 and 73 are moved in directions indicated by arrows 37 and 77, respectively, so that the optical axes of both surfaces of the first collar portion 13 are moved. Second flange forming spaces 26 and 76 adjacent to each other in a direction parallel to 46 are formed. The outer peripheral side of the second flange part forming spaces 26 and 76 is connected to the frame part forming space 75 (third step). When the second flange forming spaces 26 and 76 are formed, the molten resin is injected from the gate 29 without opening the upper die 21 and the lower die 71, and the frame portion 82 and the second flange portions 83 and 84 are formed. Molding is performed (see FIG. 19) (fourth step).

  As shown in FIG. 19, the composite molded lens 80 includes a lens body 11 having a lens portion 12 and a first flange portion 13, and a frame body 81 including a frame portion 82 and second flange portions 83 and 84. The The second flange parts 83 and 84 are injected adjacent to the front and rear surfaces of the first flange part 13 in the direction parallel to the optical axis 46 and are closely bonded. As a result, the first flange portion 13 and the second flange portions 83 and 84 are completely joined, and the lens body 11 and the frame body 81 are integrated. The optical surfaces 17 and 85 may be formed so as not to protrude from the frame body 81 in a direction parallel to the optical axis 46, and the optical surfaces 17 and 85 are hardly damaged when placed on a flat surface after molding. . The lens body 11 is preferably made of plastic, but may be made of glass because the first flange portion 13 and the second flange portions 83 and 84 are completely joined.

  In the above-described embodiment, the bonding force is much stronger than when the outer peripheral end surface of the lens unit and the frame are simply bonded, and the lens is separated even when an external force is applied due to changes in environmental temperature or incorporation into a lens frame or the like. There is nothing. In the above embodiment, the lens body has a biconvex shape. However, the shape of the lens surface is not limited to this, and may be, for example, a meniscus lens.

10, 40, 80 Compound molded lens 11, 41, 61 Lens body 12, 42, 62 Lens portion 13, 43, 63 First flange portion 14, 81 Frame body 15, 82 Frame portion 16, 44, 83, 84 Second Edge part 17,85 Optical surface 18,64 Outer peripheral end face 19 Gate part 20,50,70 Composite molding lens mold 21,51 Upper mold 22,72 Lens part core 23,73 collar part core 24,74 Frame part Core 25, 75 Frame part forming space 26, 56, 76 Second collar part molding space 29 Gate 30 Preform 31, 71 Lower mold 32, 53 Lens part forming surface 33, 54, 78 Butt part forming surface 36 Transfer surface 38 Step 46 Optical axis 52 Lens body core 65 Cylindrical surface

Claims (9)

A compound molded lens in which a press-molded lens body and a frame surrounding the lens body are integrated by injection molding,
The lens body includes a lens portion having an optical surface and a first flange portion formed so as to surround the lens portion, and the frame body includes a frame portion formed so as to surround the first flange portion and the frame. A first flange part adjacent to the optical axis direction of the first flange part, and the first flange part and the second flange part are overlapped in the optical axis direction to be in close contact bonding. A composite molded lens characterized by being made.   2. The composite molded lens according to claim 1, wherein the second collar portion is formed by injection so as to sandwich the first collar portion from the front and rear in the optical axis direction of the first collar portion.   The lens body has a cylindrical surface having a dimension in the optical axis direction between the outer periphery of the lens part and the outer periphery of the first flange part larger than the thickness dimension of the inner peripheral end of the second flange part. The composite molded lens according to claim 1, wherein the compound molded lens is formed adjacent to one surface of the portion.   The composite molded lens according to claim 1, wherein at least one surface of the lens portion does not protrude from the frame body in an optical axis direction. A preform is pressed between an upper mold and a lower mold to form a lens body having a lens portion having an optical surface and a first flange portion surrounding the outer periphery thereof, and then adjacent to the optical axis direction of the first flange portion. A composite body in which a frame body integrally formed on an inner diameter side of a frame portion formed so that a second collar portion whose outer peripheral side is connected to the frame body surrounds the first collar portion is formed by injection molding. A mold for a molded lens,
At least one of the upper mold and the lower mold is
A lens part core for compression molding the lens part;
After the first collar portion is compression molded, the collar moves in a direction opposite to the press direction of the preform to form a second collar portion forming space adjacent to one surface of the first collar portion in the optical axis direction. A core for department,
A compound molded lens mold comprising: a frame core having a frame molding space for holding the collar core movably in the press direction and forming the frame.   6. The composite molding according to claim 5, wherein the upper mold and the lower mold include the lens part core, the collar part core, and the frame part core, each of which is independently movable. Lens mold.   7. The mold for compound molded lenses according to claim 5, wherein the frame molding space is formed across the upper mold and the lower mold.   In the upper mold, the lens part core and the collar part core are integrated so that the collar part forming surface of the collar part core that presses the preform protrudes from the outer peripheral end of the lens part core. 6. The composite according to claim 5, wherein a cylindrical surface having a dimension in the optical axis direction larger than a thickness dimension of an inner peripheral end of the second collar part is formed inside the collar part forming surface. Molded lens mold. A method of manufacturing a composite molded lens in which a press-molded lens body and a frame surrounding the lens body are integrated by injection molding,
A first step of placing an optical material preform between an upper mold and a lower mold;
A second step of pressing the preform to mold the lens body having a first flange on the outside of the optical surface;
A second collar molding space adjacent to one surface of the first collar in the optical axis direction by moving the collar core formed by compression molding the first collar in a direction opposite to the press direction of the preform. A third step of forming
A fourth step of sequentially injecting molten resin into the second flange part forming space and the frame part forming space formed on the outer peripheral side thereof to form the frame body including the second flange part and the frame part is sequentially performed. A method for producing a composite molded lens, characterized in that

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