TW202006413A - Lens cap production method, lens cap production device, and lens cap - Google Patents

Abstract

This lens cap production device (20) is provided with: a first mold (21) which serves as a fixed mold; and a second mold (22) which serves as a movable mold. The first mold (21) has formed therein a molding surface (28) which serves as a mold form when a lens part (3) is provided to a cap base material (2). The molding surface (28) is provided with: a stepped recess (29) which serves as a mold form for the lens part (3); and a support surface (33) which supports a crown (5) of the cap base material (2) during the formation of the lens part (3). The stepped recess (29) is formed in so-called countersunk shape.

Description

Lens cap manufacturing method, lens cap manufacturing device and lens cap

The present invention relates to a lens cap manufacturing method, a lens cap manufacturing device, and a lens cap used when a cap base material forms a lens portion.

In the past, in the field of optical communications, lens caps that make the combination of optical communications more efficient have been widely used. The lens cap is manufactured by providing a lens portion on the cap base material. As a manufacturing method of such a lens cap, for example, it is disclosed in Patent Document 1 and the like.

Patent Document 1: Japanese Patent Laid-Open No. 2007-310379

In addition, if the lens portion is not accurately formed on the cap base material, there is a problem that the focal length of the lens portion varies. Therefore, there is a need for technology development capable of manufacturing the lens portion with high accuracy on the cap base material.

An object of the present invention is to provide a cap manufacturing method, a cap manufacturing apparatus, and a lens cap that can suppress variations in accuracy when a cap base material forms a lens portion.

A method for manufacturing a lens cap to solve the above problem is to arrange a cap base material having a shape of a cylindrical portion and a top portion provided on one side end of the cylindrical portion in a first mold and a second mold that operate in a manner close to and away from each other Between, the lens base material disposed in the hole at the top of the cap base material is hot-pressed to deform the lens base material into a shape along the molding surface of the first mold and the second mold, thereby A method of forming the lens portion to cover the hole, and forming a stepped concave portion of the mold box of the lens portion on the molding surface of the first mold and a supporting surface supporting the top portion during processing of the lens base material, to The support surface supports the entire portion of the top except for the periphery of the hole, and at the same time, the lens base material is hot-pressed in a state where the molding surface of the second mold is separated from the cap substrate, thereby forming on the cap substrate The lens part.

According to this configuration, when the lens base is formed with the cap base, the top of the cap base can be firmly supported by the support surface of the molding surface of the first mold. Therefore, when the lens base material is processed into a lens portion by hot pressing, even if a load is applied to the top of the cap base material from the lens base material, the load can be supported by the support surface of the molding surface. As a result, the top of the cap base material is less likely to warp, and the lens portion can be accurately provided on the cap base material. Therefore, it is possible to suppress variations in accuracy when the cap base material forms the lens portion.

In the above method of manufacturing a cap base material, it is preferable that the cap base material is arranged such that the surface of the top faces the first mold of the fixed type, and the back surface of the top faces the second mold of the movable type. According to this configuration, when the cap base material forms the lens portion, the operation amount of the movable second mold can be adjusted, and the inner surface side of the lens portion can be processed with high accuracy. Therefore, it is advantageous to ensure the accuracy of the focal length of the lens portion.

In the above method of manufacturing a lens cap, preferably, the first mold is a lower mold and the second mold is an upper mold. According to this configuration, since the cap base material can be placed in the first mold, the cap base material can be simply installed in the first mold.

In the manufacturing method of the lens cap described above, it is preferable that the recessed portion is a stepped cavity, and the stepped cavity is formed by a continuous large-diameter cavity and a small-diameter cavity. The large-diameter cavity is formed by the inner wall surface along the vertical direction. The small-diameter cavity is formed deeper than the large-diameter cavity and formed as a small diameter. According to this configuration, the large diameter hole provided in the concave portion of the first mold can form a locking portion with the lens base and the cap base material. In addition, the small-diameter hole provided in the concave portion of the first mold can form a light transmission portion of a desired shape of the lens portion.

The lens cap manufacturing apparatus for solving the above-mentioned problem is to arrange the cap base material having the shape of a cylinder portion and a top portion provided on one side end of the cylinder portion in the first mold and the second mold that operate in a manner close to and away from each other In between, the lens base material disposed at the top of the cap base material is hot-pressed to deform the lens base material into a shape along the molding surface of the first mold and the second mold, thereby making The lens portion is formed so as to cover the hole. On the molding surface of the first mold, a stepped concave portion that becomes the mold box of the lens portion and a support surface that supports the top portion during processing of the lens base material are provided. When the lens portion is formed on the cap base material, the entire surface except the hole in the top is supported by the support surface, and the lens base is separated from the cap base material in a state where the molding surface of the second mold is separated The material is hot-pressed to form the lens portion.

The lens cap for solving the above-mentioned problem is a structure including a lens base formed as a unilateral bottomless cylindrical cap base and a hole mounted on the top of the cap base, and the lens part is formed to be locked to the top The first locking portion on the surface and the second locking portion locked on the back of the top portion, the thickness of the top portion locked between the first locking portion and the second locking portion is set to d When the height of the first locking portion is h and the width of the first locking portion is w, d is set to a value of 0.08 to 0.30 mm, and h is set to 0.08 to 0.40 mm Value, w is set to a value of 0.03 ~ 0.50 mm.

According to the present invention, variations in accuracy when the cap base material forms the lens portion can be suppressed.

Hereinafter, an embodiment of the lens cap manufacturing method, lens cap manufacturing apparatus, and lens cap will be described with reference to FIGS. 1 to 11.

As shown in FIGS. 1 and 2, the lens cap 1 includes a single-sided bottomless cylindrical cap base material 2 forming the body portion of the lens cap 1 and a lens portion 3 attached to the cap base material 2. The lens cap 1 is, for example, mounted and fixed to a rod provided with an optical semiconductor element or the like, and in this mounted state, airtightness of the space inside the cap is ensured. The lens cap 1 efficiently couples optical communication between the optical semiconductor element in the cap and the optical fiber outside the cap through the lens portion 3.

The cap base material 2 includes a cylindrical portion 4 that forms the body portion of the cap base material 2 and a top portion 5 that is formed to close one of the axial end portions of the cylindrical portion 4. The cylindrical portion 4 is formed in a cylindrical shape. Around the opening 6 formed at the other end in the axial direction of the cylindrical portion 4, a flange portion 7 protruding radially outward of the cap base 2 is formed in the entire circumferential direction. In the center of the top portion 5, a hole 8 for mounting and fixing the lens portion 3 is provided through. For the material of the cap base 2, for example, nickel-iron alloy and nickel plating are used.

The lens portion 3 includes a first lens curved portion 9 located outside the lens cap 1 and a second lens curved portion 10 located inside the lens cap 1. The first lens curved portion 9 and the second lens curved portion 10 are formed at positions where their axes coincide, and the first lens curved portion 9 is formed to have a larger radial dimension than the second lens curved portion 10.

The lens portion 3 is formed with a first locking portion 11 locked to the surface of the top 5 and a second locking portion 12 locked to the back of the top 5. The first locking portion 11 is formed on the periphery of the first lens curved portion 9 over the entire circumferential direction. The second locking portion 12 is formed on the periphery of the second lens curved portion 10 over the entire circumferential direction. In the case of this example, the second locking portion 12 is formed to have a length that protrudes more radially outward of the lens portion 3 than the first locking portion 11. The lens portion 3 is locked to the groove portion 13 formed between the first locking portion 11 and the second locking portion 12 by the edge of the top portion 5, so as to be fixed to the cap base 2.

Here, the thickness of the top 5 locked between the first locking portion 11 and the second locking portion 12 is set to "d", the height of the first locking portion 11 is set to "h", and the first The width of one locking portion 11 is set to "w". In this case, the thickness d is preferably 0.08 mm or more, more preferably 0.10 mm or more, and most preferably 0.12 mm or more. In the case of 0.08 mm or more, the airtightness of the space inside the cap can be more reliably maintained by improving the durability against the lens portion 3 accompanying the impact of welding. The thickness d is preferably 0.30 mm or less, more preferably 0.28 mm or less, and most preferably 0.26 mm or less. In the case of 0.30 mm or less, the press productivity of the cap base material is improved.

The height h of the first locking portion 11 is preferably 0.08 mm or more, more preferably 0.11 mm or more, and most preferably 0.14 mm or more. In the case of 0.08 mm or more, the durability of the lens portion 3 against the pressure at the time of thermal shock is improved. In addition, the height h of the first locking portion 11 is preferably 0.40 mm or less, more preferably 0.35 mm or less, and most preferably 0.30 mm or less. In the case of 0.4 mm or less, it is easy to process such that the jig 34 does not contact the corner of the support surface 33.

The width w of the first locking portion 11 is preferably 0.03 mm or more, more preferably 0.5 mm or more, and most preferably 0.07 mm or more. In the case of 0.03 mm or more, it is possible to more reliably prevent the lens from falling off the cap base material. In addition, the width w of the first locking portion 11 is preferably 0.50 mm or less, more preferably 0.40 mm or less, and most preferably 0.30 mm or less. In the case of 0.50 mm or less, the deformation of the hole 8 is less likely to be caused when the lens is molded, whereby the deviation of the focal length can be more surely prevented.

FIG. 3 shows the manufacturing apparatus of the lens cap 1 (lens cap manufacturing apparatus 20). The lens cap manufacturing apparatus 20 of this example includes a first mold 21 and a second mold 22 that become a mold box formed in the lens portion 3 of the cap base 2, a sleeve 23 that positions the cap base 2 from the radial direction, and a The stopper 24 of the outer frame of the lens cap manufacturing device 20. The first mold 21 and the second mold 22 are arranged on the same axis (on the axis L1), and are arranged to face each other. The sleeve 23 and the stopper 24 are placed on the first mold 21.

As shown in FIGS. 3 and 4, the first die 21 includes a large-diameter base 25 formed at the lowermost stage, an intermediate stage 26 formed at the upper surface of the base 25, and a protrusion formed at the upper surface of the intermediate stage 26 27. The base portion 25, the middle section portion 26 and the protruding portion 27 are arranged on the same axis. The first mold 21 in this example is a fixed type with a constant position, and is a lower mold disposed below the second mold 22. As shown in FIG. 4, the first mold 21 is formed in a substantially disc shape.

As shown in FIG. 3, the upper surface of the first mold 21 (protruding portion 27) (the surface facing the second mold 22) becomes the molding surface on the side of the first mold 21 when the lens portion 3 of the cap base 2 is formed ( Hereinafter, it is described as the molding surface 28). The molding surface 28 is formed with a stepped concave portion 29 that becomes a mold box of the lens portion 3. The concave portion 29 in this example is a stepped hole, and the stepped hole is formed by a large-diameter hole 31 and a small-diameter hole 32 which are formed by the inner wall surface 30 along the vertical direction, the small-diameter hole 32 is located deeper than the large-diameter hole 31 and formed as a small diameter.

In the case of this example, the angle θ formed by the inner wall surface 30 with respect to the vertical direction (reference line La in FIG. 3) is preferably 90.1° or more, more preferably 90.2° or more, and most preferably 90.3° or more. In the case of 90° or more, it is easy to remove the lens base material contacting the inner wall surface 30 from the first mold 21 after the lens is formed. The angle θ formed by the inner wall surface 30 is preferably 120° or less, more preferably 115° or less, and most preferably 110° or less. In the case of 120° or less, it is difficult to cause deformation of the hole 8 when the lens is molded, and thereby it is possible to more surely prevent the deviation of the focal length. The small-diameter hole 32 is a portion where the first lens curved portion 9 is formed, and is formed in a curved shape.

The molding 28 of the first mold 21 is provided with a support surface 33 that supports the top 5 of the cap base 2 when the lens portion 3 is formed. The support surface 33 in this example is formed in a planar shape and is formed over the entire circumference of the recess 29. The support surface 33 is formed to be able to support the area and shape of the entire top portion 5 of the cap base 2 except the hole 8.

As shown in FIG. 5, the small-diameter hole 32 of the concave portion 29 (molding surface 28) is formed by grinding the surface of the protruding portion 27 of the first mold 21 with a jig 34. As this manufacturing method, for example, while rotating the jig 34 around the axis L2 (direction of arrow R1 in FIG. 5 ), it is operated by rubbing the recess 29 (direction of arrow R2 in FIG. 5) while forming the recess 29 (molding Face 28). In the case of this manufacturing method, in order to prevent the jig 34 from contacting the corner of the support surface 33, it is preferable to ensure the width D of the bottom surface of the large-diameter hole 31 to a certain extent.

As shown in FIGS. 3 and 6, the second mold 22 includes a body 35 and a protrusion 36 formed on the back of the body 35. The second mold 22 in this example is a movable type that approaches and moves away from the first mold 21, and is an upper mold that is disposed above the first mold 21. The body portion 35 and the protruding portion 36 are arranged on the same axis. The back surface (the surface facing the first mold 21) of the second mold 22 (protruding portion 36) becomes a molding surface (hereinafter referred to as a molding surface 37) on the second mold 22 side when the lens portion 3 of the cap base 2 is formed. ). The molding surface 37 is a portion where the second lens curved portion 10 is formed, and is formed in a curved shape. As shown in FIG. 6, the second mold 22 is formed in a substantially cylindrical shape.

As shown in FIGS. 3 and 7, on the inner circumferential surface of the sleeve 23, a protrusion 38 protruding in the entire circumferential direction is formed, and the protrusion 39 of the first mold 21 is attached to the hole 39 in the center of the protrusion 38 27. As shown in FIG. 7, the sleeve 23 is formed in a substantially cylindrical shape.

As shown in FIGS. 3 and 8, the stopper 24 is disposed on the upper surface of the base portion 25 of the first mold 21, and the storage portion 40 installed inside accommodates the first mold 21, the second mold 22, and the sleeve 23. As shown in FIG. 8, the stopper 24 is formed in a substantially cylindrical shape.

Next, the manufacturing procedure of the lens cap 1 will be described using FIG. 9.

As shown in FIG. 9( a ), the second mold 22 slides upward to make the inside of the sleeve 23 open, and the cap base 2 is installed in the lens cap manufacturing apparatus 20. In the case of this example, the cap base 2 is placed on the first mold 21 downward. That is, the cap base 2 is provided on the first mold 21 with the opening 6 positioned above and the top 5 positioned below. At this time, the top 5 of the cap base 2 is placed so as to contact the support surface 33 of the molding surface 28 of the first mold 21. In addition, the cap base material 2 is arranged so that its outer circumferential surface faces the inner circumferential surface of the sleeve 23 so as to be positioned in the radial direction. That is, the cap base 2 is provided so as to fit into the recess formed by the first mold 21 and the sleeve 23.

As shown in FIG. 9( b ), the lens base material 41 is provided on the cap base material 2 provided in the first mold 21. The lens base material 41 in this example is, for example, a spherical member (ball). In the case of this example, since the cap base material 2 is provided downward, when the lens base material 41 is put in, the lens base material 41 is easily positioned in the hole 8. Therefore, the installation of the lens base material 41 is easy.

As shown in FIG. 9(c), after the cap base material 2 and the lens base material 41 are installed in the first mold 21, the second mold 22 is slid downward toward the first mold 21 (in the direction of arrow R3 in the same figure) So that the molding surface 37 of the second mold 22 contacts the lens base material 41.

As shown in FIG. 9( d ), after the second mold 22 is brought into contact with the lens base material 41, the lens base material 41 is heated and pressurized in an atmospheric environment (hot press processing). In addition, the hot-pressing process may be in either a nitrogen atmosphere or an atmospheric environment. In the case of this example, the lens base material 41 is thermally processed with the molding surface 37 of the second mold 22 separated from the cap base 2. Then, if the lens base material 41 is heated and softened by this thermal processing, the lens base material 41 deforms according to the surrounding shape and is processed into a desired lens shape. Then, after this hot working, the lens portion 3 is cooled, and the cap base 2 and the lens portion 3 are taken out of the lens cap manufacturing device 20 to form the integrated lens cap 1. With the above, the manufacturing of the lens cap 1 is completed.

Next, the operation and effect of the lens cap 1 (method of manufacturing a lens cap) of the present embodiment will be described using FIGS. 10 and 11.

FIG. 10 shows a prior art positioning lens cap manufacturing method. In the case of the prior art shown in the same figure, the molding surface 28 of the first mold 21 is an example in which the inner wall surface 30 of the large-diameter cavity 31 of the recess 29 is inclined (conical). In the case of this manufacturing method, since the width of the support surface 33 cannot be sufficiently secured, an excessive load is applied to the top 5 of the cap base material 2 when the lens base material 41 is hot-pressed. Therefore, a load may be applied to the direction of arrow Ra in the figure, and the periphery of the hole 8 of the top 5 may be unnecessarily deformed. If this is the case, the position of the lens portion 3 in the lens cap 1 of the finished product will change, and the focus distance deviation will be affected.

On the other hand, as shown in FIG. 11, in the case of the manufacturing method of this example, the width of the support surface 33 is sufficiently ensured (this example corresponds to “D” shown in FIG. 5 ). Therefore, even when the lens base material 41 is subjected to a load on the top portion 5 of the cap base material 2 during the hot press processing of the lens base material 41, the top portion 5 is firmly held by the support surface 33 in a wide range. Therefore, the periphery of the hole 8 of the top 5 is not unnecessarily deformed. Therefore, it is possible to make it difficult to change the focal length of the lens unit 3 and improve the focal length accuracy.

In addition, in the case of this example, when the cap base 2 forms the lens portion 3, the top 5 of the cap base 2 can be firmly supported by the support surface 33 of the molding surface 28 of the first mold 21. Therefore, even when the lens base material 41 is heated and processed into the lens portion 3, the load is applied to the top surface 5 of the cap base material 2 from the lens base material 41, the load can be supported by the support surface 33 of the molding surface 28. As a result, the top portion 5 of the cap base 2 is less likely to warp, and the lens portion 3 can be accurately provided on the cap base 2. Therefore, variations in accuracy when the cap base 2 forms the lens portion 3 can be suppressed. Even the deviation of the focal length of the lens portion 3 can be suppressed.

The cap base 2 is configured such that the surface of the top 5 faces the first mold 21 of the fixed type, and the back surface of the top 5 faces the second mold 22 of the movable type. In this case, when the lens base 3 is formed by the cap base 2, the operation amount of the movable second mold 22 (the amount of movement in the downward direction relative to the first mold 21) can be adjusted, etc. The inner surface side of 3 (second lens curved surface portion 10) is processed with high accuracy. Therefore, it is advantageous to ensure the accuracy of the focal length of the lens portion 3.

In addition, the cap base material 2 may also be arranged such that the back surface of the top 5 faces the first mold 21 of the fixed type, and the surface of the top 5 faces the second mold 22 of the movable type. Even in this case, the load when the load is applied to the top 5 of the cap base 2 from the lens base material 41 can be supported by the support surface 33 of the molding surface 28. As a result, the top portion 5 of the cap base 2 is less likely to warp, and the lens portion 3 can be accurately provided on the cap base 2. Therefore, it is possible to suppress variations in accuracy when the lens portion 3 is formed on the cap base 2.

In addition, the operation of placing the lens base material 41 inside the cap base material 2 and aligning the lens base material 41 with the hole 8 can be easily performed. Therefore, the installation of the lens base material 41 can be easily performed.

The first mold 21 is a lower mold, and the second mold 22 is an upper mold. Therefore, since the cap base material 2 can be set to be placed on the first mold 21, the cap base material 2 can be simply set on the first mold 21.

The groove 29 is a stepped hole. The stepped hole is formed by the large-diameter hole 31 and the small-diameter hole 32 continuously. The large-diameter hole 31 is formed by the inner wall surface 30 along the vertical direction. The small-diameter hole 32 is located Deeper than the large-diameter hole 31, a small diameter is formed at the same time. Therefore, the large-diameter hole 31 of the concave portion 29 can form the locking portion (the first locking portion 11) of the lens portion 3 and the cap base material 2. In addition, by the small-diameter holes 32 of the concave portion 29, a light transmission portion (first lens curved portion 9) of a desired shape of the lens portion 3 can be formed.

In addition, this embodiment can be implemented by changing as follows. The present embodiment and the following modification examples can be implemented in combination with each other within a range where there is no technical conflict.

The heating source of the lens base material 41 may be arranged to cover the outer periphery of the stopper 24, or may be arranged outside it.

The hot press processing of the lens base material 41 is not limited to a method of heating and pressurizing in an environment, and for example, a method of using a laser (laser softening) may be used.

The second locking portion 12 may be formed in the shape of the entire back region of the top 5 of the cap base 2.

The support surface 33 and the concave portion 29 of the first mold 21 may have a shape that can firmly support the top portion 5 of the cap base 2 when the lens portion 3 is manufactured.

The shape of the concave portion 29 is not limited to the stepped shape (reaming shape) having the large-diameter hole 31 and the small-diameter hole 32 as in this example, as long as it can support the top 5 of the cap base material 2 while molding the lens portion 3 The shape of the necessary lens part 3 may be sufficient.

The material of the cap base 2 can be appropriately changed to a type other than the examples. For example, SUS430, SUS430F, SF-20F, SF-20T, etc. may be mentioned. In addition, the material of the cap base material 2 may be made of a metal material other than SUS material, or may be made of an alloy of nickel and iron.

The sleeve 23 may be a separate structure in which the body portion of the sleeve 23 and the protrusion 38 are separate members.

The lens cap manufacturing apparatus 20 is not limited to the structure having the first mold 21, the second mold 22, the sleeve 23, and the stopper 24, and other structures may be applied.

The sleeve 23 and the stopper 24 can be appropriately changed to shapes or structures other than the embodiment. In addition, the lens cap manufacturing device 20 does not necessarily need to include the sleeve 23 and the stopper 24, as long as it is a device having members having the same function.

The first mold 21 and the second mold 22 can interchange the lower mold and the upper mold. In addition, the first mold 21 and the second mold 22 are interchangeable with a fixed type and a movable type.

The first mold 21 and the second mold 22 may be both movable.

The area of the top portion 5 supported by the support surface 33, that is, the entire area except for the periphery of the hole 8 only needs to have an area necessary for the cap base material 2 not to warp during processing.

The lens cap manufacturing apparatus 20 may be such that the outer side of the cap base 2 faces the second mold 22 and the back side of the cap base 2 faces the first mold 21, thereby manufacturing the lens cap 1.

The lens cap manufacturing apparatus 20 can be appropriately changed to other than the embodiment.

1‧‧‧ lens cap 2‧‧‧Cap base material 3‧‧‧Lens Department 5‧‧‧Top 8‧‧‧hole 11‧‧‧First locking part 12‧‧‧Second locking part 20‧‧‧ Lens cap manufacturing device 21‧‧‧ First mold 22‧‧‧Second mould 28‧‧‧Forming surface 29‧‧‧recess 31‧‧‧Large diameter hole 32‧‧‧small diameter hole 33‧‧‧Support surface 37‧‧‧Forming surface 41‧‧‧Lens base material

FIG. 1 is a longitudinal cross-sectional view of a lens cap according to an embodiment. 2 is a perspective view of a lens cap. 3 is a configuration diagram of a lens cap manufacturing device. 4 is a plan view of the first mold viewed from the molding surface side. FIG. 5 is an explanatory diagram showing a method of manufacturing the molding surface of the first mold. 6 is a plan view of the second mold viewed from the molding surface side. 7 is a top view of the sleeve. Fig. 8 is a top view of the stopper. 9(a) to (d) are step diagrams showing the manufacturing procedure of the lens cap. 10 is an explanatory diagram of a prior art positioning lens cap manufacturing method. FIG. 11 is an explanatory diagram of a method of manufacturing a lens cap according to an embodiment.

2‧‧‧Cap base material

3‧‧‧Lens Department

4‧‧‧Cylinder

5‧‧‧Top

6‧‧‧ opening

7‧‧‧Flange

8‧‧‧hole

20‧‧‧ Lens cap manufacturing device

21‧‧‧ First mold

22‧‧‧Second mould

23‧‧‧Sleeve

25‧‧‧Base

26‧‧‧Middle section

27‧‧‧Projection

28‧‧‧Forming surface

29‧‧‧recess

33‧‧‧Support surface

35‧‧‧Body

36‧‧‧Projection

37‧‧‧Forming surface

38‧‧‧Protrusion

39‧‧‧ Hole

41‧‧‧Lens base material

R3‧‧‧arrow

Claims (6)

A method for manufacturing a lens cap, a cap base material having a shape of a cylindrical portion and a top portion provided on one side end of the cylindrical portion is arranged between a first mold and a second mold which operate in a manner close to and away from each other. The lens base material disposed in the hole at the top of the cap base material is hot-pressed to deform the lens base material into a shape along the molding surface of the first mold and the second mold, thereby forming the lens portion To cover the hole, it is characterized by, On the molding surface of the first mold, a stepped concave portion that becomes a mold box of the lens portion and a support surface that supports the top portion during processing of the lens base material are provided, and the support surface supports the top portion except for the periphery of the hole At the same time, the lens base material is hot-pressed while the molding surface of the second mold is separated from the cap base material, thereby forming the lens portion on the cap base material. The method for manufacturing a lens cap according to claim 1, wherein the cap base is configured such that the surface of the top faces the first mold of the fixed type, and the back surface of the top faces the second mold of the movable type. The method for manufacturing a lens cap according to claim 2, wherein the first mold is a lower mold and the second mold is an upper mold. The method for manufacturing a lens cap according to any one of claims 1 to 3, wherein the concave portion is a stepped cavity, and the stepped cavity is formed by a continuous large-diameter cavity and a small-diameter cavity, the large-diameter cavity is along the inner wall surface Formed in a vertical direction, the small-diameter hole is formed deeper than the large-diameter hole and formed as a small diameter. A lens cap manufacturing apparatus, a cap base material having a shape of a cylinder and a top portion provided on one side end of the cylinder is disposed between a first mold and a second mold that operate in a manner close to and away from each other. The lens base material disposed in the hole at the top of the cap base material is hot-pressed to deform the lens base material into a shape along the molding surface of the first mold and the second mold, thereby forming the lens portion To cover the hole, it is characterized by, On the molding surface of the first mold, a stepped concave portion that becomes a mold box of the lens portion and a support surface that supports the top portion during processing of the lens base material are provided, In the case where the lens portion is formed on the cap base material, the entire surface except the hole in the top portion is supported by the support surface, while the forming surface of the second mold is separated from the cap base material The lens base material is hot-pressed to form the lens portion. A lens cap is provided with a cap base material formed in a single-sided bottomless cylindrical shape, and a lens portion with a hole mounted on the top of the cap base material, characterized in that: Forming a first locking portion locked on the surface of the top and a second locking portion locked on the back of the top on the lens portion, The thickness of the top portion locked between the first locking portion and the second locking portion is d, the height of the first locking portion is h, and the height of the first locking portion is When the width is set to w, d is set to a value of 0.08 to 0.30 mm, h is set to a value of 0.08 to 0.40 mm, and w is set to a value of 0.03 to 0.50 mm.

Images