JP2014182199A - Aspherical lens and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly productive method of manufacturing an aspherical lens having a thick lens portion using injection molding.SOLUTION: A method of manufacturing an aspherical lens includes; forming a first outer shell 51 using a molding resin in a first cavity created between a core section of a fixed metallic mold 10 and a cavity section of a movable metallic mold 30 and, at the same time, forming a second outer shell 52 using the molding resin in a second cavity created between a cavity section of the fixed metallic mold 10 and a core section of the movable metallic mold 30; forming a welding flange section 54 using the molding resin in a third cavity 26 created by sliding the movable metallic mold 30 to position the cavity section of the movable metallic mold 30 with the first outer shell 51 right opposite the cavity section of the fixed metallic mold 10 with the second outer shell 52 and clamping the molds; welding the first outer shell 51 and the second outer shell 52 together to form a hollow lens having a hollow inner space; and filling the hollow inner space of the hollow lens with a filler resin to form an aspherical lens in a later step.

Description

  The present invention relates to an aspheric lens and a method for manufacturing the same, and more particularly to an aspheric lens and a method for manufacturing the aspheric lens by injection molding.

  A method for molding an aspherical lens by injection molding is disclosed, for example, in Cited Document 1 as “a method for manufacturing a headlamp lens”.

  The method for manufacturing a headlamp lens (aspheric lens) disclosed in the cited document 1 relates to a molding method that does not cause sink marks in the injection molding of an aspheric lens having a thick part. Specifically, as shown in FIG. 15, the molding die is composed of a flat part mold 80 and a convex part mold 81, and the convex part mold 81 is composed of a fixed part 81a and a moving part 81b. .

  At the time of injection molding, the movable portion 81b of the convex portion mold 81 is positioned on the flat portion mold 80 side by an appropriate amount from the design dimension of the thickness of the headlamp lens. The first cavity 82 formed by the part die 81 is filled with a molding resin and subjected to primary injection molding, and the molding resin is cooled and solidified as it is to form a semi-finished product 83 for a headlamp lens. Then, in the semi-finished product 83, an amount of sink marks 84 corresponding to the curing shrinkage rate of the molding resin is generated.

  Next, as shown in FIG. 16, the moving portion 81b of the convex surface mold 81 is moved to a position where the design dimension of the thickness of the headlamp lens is reached. Then, the second cavity 85 including the sink 84 of FIG. 15 is formed on the plane part mold 80 side by the movement of the moving part 81b. The second cavity 85 is filled with a molding resin to perform secondary injection molding, and the molding resin is cooled and solidified as it is to form a product for the headlamp lens 86.

  Then, as shown in FIG. 17, the injection molded product of the headlamp lens 86 taken out from the flat surface portion mold 80 and the convex surface portion mold 81 is caused by the secondary injection molding. Therefore, the headlight lens 86 without sink marks can be obtained.

JP 2000-113701 A

  By the way, in the above-described method for manufacturing a headlamp lens, if the molding resin is, for example, a thermoplastic acrylic resin, the thermoplastic acrylic resin has a low thermal conductivity (for example, the thermal conductivity of iron is 84 W / (m · K), whereas the acrylic resin has a thermal conductivity of 0.15 W / (m · K)), and the molding resin filled in the cavity is cooled and cured from the part in contact with the mold surface. Begins and gradually progresses into the thick lens section. Therefore, in particular, in an aspherical lens having a thick part, it takes time to cool the molding resin filled in the cavity.

FIG. 18 shows a molding in which the diameter (D) of the lens portion of the aspherical lens is set to 58 mmφ, the maximum thickness (H _MAX ) is set to 19 mm, and the thickness (H _F ) of the flange portion is set to 2.5 mm. the temperature change after completion filling of the resin, the thick thickness direction of the center position of the lens unit of the meat (the position of the P ₁₎ and the thickness direction of the center position of the flange portion of the aspherical lens (the position of the P _2), This is obtained using resin flow analysis (see FIG. 17).

The horizontal axis in the figure represents the time (time elapsed) from the completion of resin filling, and the vertical axis represents the temperature (temperature change) of the filled molding resin. In the figure, the molding resin in the center position of the flange portion (the position of the P _2), the time to be cooled to the same temperature as the temperature of the mold is 280 seconds, the lens portion center position (the P ₁ The molding resin positioned at (position) indicates that the time until cooling to the same temperature as the mold temperature is 1200 seconds.

  Therefore, from the result of the resin flow analysis, it can be seen that the injection molding of the aspherical lens having the thick lens portion has poor productivity because the molding cycle time is long.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a highly productive manufacturing method by injection molding for an aspheric lens having a thick lens portion. It is in.

  In order to solve the above problems, the invention described in claim 1 of the present invention is formed of a first outer shell portion made of a first resin member and a second outer shell portion made of a second resin member. A hollow lens having a hollow portion, and a filling resin made of a third resin member filled in the hollow portion of the hollow lens, the first resin, the second resin, and the third resin. These resins all have the same refractive index.

  In the invention described in claim 2 of the present invention, the fixed mold and the movable mold each having a core part and a cavity part are primarily clamped, and the core part of the fixed mold and the movable mold are A first cavity is formed by the cavity portion and a second cavity is formed by the cavity portion of the stationary mold and the core portion of the movable mold; and the first cavity and the first cavity are formed by primary injection molding. Filling the two cavities with molding resin to form the first molded product and the second molded product, respectively, sliding the movable mold after opening the fixed mold and the movable mold, and moving the movable mold The cavity part where the first molded product of the mold remains is opposed to the cavity part of the fixed mold where the second molded product remains, and a secondary mold is clamped to form a third cavity connected to the second molded product. Process and secondary injection molding A step of filling the third cavity with a molding resin to form a third molded product integrated with the second molded product, and simultaneously welding the first molded product and the second molded product, and the fixing A step of opening the mold and the movable mold to take out a hollow lens having a hollow portion, which is constituted by the first molded product, the second molded product, and the third molded product; And a step of forming an aspheric lens by filling and filling the hollow portion with a filling resin.

  According to a third aspect of the present invention, there is provided a resin injection path and a gas which serve as an injection path when the filling resin is injected into the hollow portion of the hollow lens by the primary injection molding. A gas vent passage serving as a vent passage is formed.

  According to a fourth aspect of the present invention, in the second or third aspect, the first cavity and the second cavity have different volumes and are connected via a gate, and the primary injection molding is performed. The gate with the gate cut pin is inserted into the gate before the cavity having the smaller volume is filled with the molding resin and the cavity having the larger volume is being filled and the molding resin filled in the cavity having the smaller volume is solidified. It protrudes and the said 1st cavity and the said 2nd cavity are isolate | separated within a metal mold | die.

  Further, in the invention described in claim 5 of the present invention, in claim 2 or claim 3, the molding resin is a thermoplastic resin, the filling resin is a crosslinked resin, and the molding resin and the filling resin are refracted. The rate is made of the same resin material.

  The manufacturing method of the aspherical lens according to the present invention is such that the first molded product is molded by the first cavity formed by the core part of the fixed mold and the cavity part of the movable mold by the primary injection molding and at the same time the cavity of the fixed mold. The second mold is formed with the second cavity formed by the core part of the movable mold and the movable mold, and then the movable mold is slid and the cavity part where the first molded product of the movable mold remains is fixed mold. Forming the third molded product by secondary injection molding with respect to the third cavity formed by clamping the second molded product facing the remaining cavity, and welding the first molded product and the second molded product. A hollow lens having a hollow was formed, and an aspherical lens was formed by filling the hollow portion of the hollow lens with a filling resin in a later step.

  As a result, the tact time is shortened with respect to the conventional manufacturing direction, and the production efficiency can be increased. In addition, it is not necessary to consider the occurrence of sink marks, which is a problem in the conventional batch molding, in the manufacturing method of the present invention, the mold design becomes easy and the degree of freedom in design increases, and the mold manufacturing cost also increases. It can be reduced and good optical characteristics can be obtained with certainty. In other words, the manufacturing method of the aspherical lens according to the present invention can significantly improve productivity and reliably ensure optical reliability with respect to the conventional manufacturing method.

It is a longitudinal section of the hollow lens concerning the aspherical lens of an embodiment. It is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. Similarly, it is explanatory drawing of the injection molding method concerning the aspherical lens of embodiment. It is a bottom view of a hollow lens. It is C arrow line view of FIG. It is explanatory drawing which inject | pours filling resin into a hollow lens. It is explanatory drawing of the state which set the hollow lens to the jig | tool for resin injection | pouring. It is a longitudinal cross-sectional view of the aspherical lens of embodiment. It is explanatory drawing of the manufacturing method of a prior art example. Similarly, it is explanatory drawing of the manufacturing method of a prior art example. It is explanatory drawing of a prior art example. It is a graph concerning the temperature change of the molding resin of a prior art example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. 1 to 14 (the same reference numerals are given to the same portions). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  The method for producing an aspheric lens according to the present invention forms an aspheric hollow lens having a hollow portion by injection molding using an injection mold, and injects resin into the hollow portion of the hollow lens taken out from the molding die. Then, it is cured by heating to form an aspheric lens.

  As shown in FIG. 1 (longitudinal sectional view of the hollow lens), the hollow lens 50 to be molded by injection molding includes a lens portion 51a having an aspheric lens surface 51aa which is also a light emitting surface and an annular outer peripheral edge portion (flange portion) 51b. A first outer shell portion 51 made of a light incident portion 52a having a light incident surface 52aa and a second outer shell portion 52 made of an annular outer peripheral edge portion (flange portion) 52b are connected to each other via a welding flange portion 54. The hollow part 53 is formed by airtightly welding the flange parts 51b and 52b.

  The injection molding method of the hollow lens 50 will be described in detail below with reference to FIGS. FIG. 2 shows the structure of an injection mold 1 used for injection molding of the aspherical hollow lens 50.

  The injection mold 1 (hereinafter abbreviated as “mold”) includes a fixed mold 10 and a movable mold 30, and the fixed mold 10 is connected to a cylinder 60 of an injection molding machine, which will be described later, at the center. A concave nozzle touch portion (molten resin injection port) 11 with which the tip of the nozzle 61 abuts is provided and connected to the valve gate 12. The movable mold 30 is provided with a gate cut pin 32 connected to a hydraulic device 31 at the center.

  One side (A1) sandwiching the valve gate 12 of the fixed mold 10 is the core side of a cavity (first cavity 20 described later) for molding the first outer shell portion 51, and the other side (A2) is This is the cavity side of a cavity (second cavity 23 described later) for molding the second outer shell portion 52. Further, one side (B1) sandwiching the gate cut pin 32 of the movable mold 30 is the cavity side of the cavity for molding the first outer shell portion 51, and the other side (B2) is the second outer shell portion. This is the core side of the cavity for molding 52.

  The protruding portion indicated by reference numeral 33 of the movable mold 30 is a core portion (core portion for forming a resin injection path) that forms a resin injection path that becomes an injection path when resin is injected into the hollow portion 53 of the hollow lens 50. , 34 is a core portion (a degassing path forming core portion) that forms a degassing passage that becomes a degassing passage when resin is injected into the hollow portion 53 of the hollow lens 50. In addition, the protruding portion indicated by reference numeral 14 of the fixed mold 10 is a core portion that forms a cavity for forming the welding flange portion 54 of the hollow lens 50 in the secondary molding resin injection step described later (core for welding flange portion forming cavity). Part).

  Therefore, in the primary mold clamping step shown in FIG. 3, the movable mold 30 is moved in the direction of the fixed mold 10, and the butting surfaces 30a and 10a are brought into contact with each other to share the parting line 2. Clamp the mold.

  Then, the first cavity 20 for forming the first outer shell portion 51 of the hollow lens 50 is formed on the (A1) side of the fixed mold 10 and the (B1) side of the movable mold 30, and the ( A second cavity 23 for forming the second outer shell portion 52 of the hollow lens 50 is formed on the A2) side and the (B2) side of the movable mold 30.

  The first cavity 20 has a region (lens portion molding region) 21 for molding the lens portion 51 a of the first outer shell portion 51 and a region (flange portion molding region) 22 for molding the flange portion 51 b, and the second cavity 23. Has a region (light incident portion forming region) 24 for forming the light incident portion 52a of the second outer shell portion 52 and a region (flange portion forming region) 25 for forming the flange portion 52b. In this case, the volume of the first cavity 20 is larger than the volume of the second cavity 23.

  The gate 12a of the valve gate 12 is located in the flange portion forming region 22 of the first cavity 20, and the tip 32a of the gate cut pin 32 is located on the second cavity 23 side with respect to the gate 12a position of the valve gate 12. ing.

  Next, in the primary molding resin injection step of FIG. 4, the tip of the nozzle 61 connected to the cylinder 60 of the injection molding machine is brought into contact with the nozzle touch portion 11 of the fixed mold 10 and supplied into the cylinder (heating cylinder) 60. The heated melt molding resin (for example, thermoplastic acrylic resin) 3 is transferred to the tip of the heating cylinder 60 by the rotation of the screw 62, and a fixed amount of the melt molding resin 3 accumulated at the tip of the heating cylinder 60 is advanced by the screw 62. Is discharged from the nozzle 61 and supplied to the valve gate 12 by the extrusion pressure (transfer).

  The molten molding resin 3 supplied to the valve gate 12 is injected into the first cavity 20 and the second cavity 23 through the gate 12a.

  Then, as described above, since the volume of the first cavity 20 is larger than the volume of the second cavity 23, the second cavity 23 having a small volume is filled with the molten molding resin 3 first. Therefore, when the second cavity 23 is filled with the melt-molded resin and is in a molten state, the hydraulic device 31 is driven to advance the gate cut pin 32 so that the tip 32 a is communicated with the second cavity 23 in the gate 13. The gate 13 is shut off by protruding (see FIG. 5).

  Even after the gate 13 is shut off, the molten molding resin 3 continues to be injected into the first cavity 20 via the valve gate 12, and when the first cavity 20 is filled, the molten molding resin is supplied from the valve gate 12. Is stopped. Thereafter, the mold 1 is cooled and solidified by cooling.

  Next, in the mold opening process of FIG. 6, the movable mold 30 is moved in a direction away from the fixed mold 10. Then, by being divided by the gate cut pin 32, the molded product of the first outer shell portion 51 of the hollow lens 50 molded by the first cavity 20 remains on the movable mold 30 side, and the second outer shell portion. The molded product 52 remains on the fixed mold 10 side.

  Next, in the sliding and secondary mold clamping process of the movable mold 30 in FIG. 7, the movable mold 30 is moved to a position where the (B1) side of the movable mold 30 faces the (A2) side of the fixed mold 10. Further, the movable mold 30 is moved in the direction of the fixed mold 10, and the abutting surfaces 30 a and 10 a are brought into contact with each other to perform the mold clamping to share the parting line 2.

  Then, the light incident portion 52a of the second outer shell portion 52 remaining on the fixed mold 10 side and the lens portion 51a of the first outer shell portion 51 remaining on the movable mold 30 side face each other, and at the same time, the second outer The surfaces of the flange portion 52b of the shell portion 52 and the flange portion 51b of the first outer shell portion 51 facing each other are brought into surface contact with each other. The annular third cavity 26 communicates with the gate 12 a of the valve gate 12 and extends outward from the flange portion 52 b of the second outer shell portion 52 and along the back surface of the flange portion 51 b of the first outer shell portion 51. Is formed.

  Next, in the secondary molding resin injection step of FIG. 8, similarly to the primary molding resin injection step, the molten molding resin (primary molding resin injection step) supplied to the valve gate 12 from the nozzle 61 connected to the cylinder 60 of the injection molding machine. 3 is injected into the third cavity 26 through the gate 12a, and then cooled and solidified with the cooling of the mold 1 to form the welding flange portion 54. The The molten molding resin 3 injected into the third cavity 26 also has a function of hermetically welding the flange portion 52b of the second outer shell portion 52 and the flange portion 51b of the first outer shell portion 51 at the same time. .

  Next, in the mold opening process of FIG. 9, the movable mold 30 is moved away from the fixed mold 10, and the secondary molded product remaining in the movable mold 30 is removed from the mold and taken out. Then, the molded product has the welding flange portion 54 itself, and at the same time, the flange portions 51b and 52b of the first outer shell portion 51 and the second outer shell portion 52 which are molded in the primary molding resin injection process, The hollow lens 50 is hermetically welded by the welding flange 54 molded in the secondary molding resin injection process.

  10 and 11 are external views of the hollow lens 50 obtained by two primary and secondary injection moldings. 10 is a bottom view, and FIG. 11 is a view taken in the direction of arrow C in FIG.

  The hollow lens 50 includes a first outer shell portion 51 having a lens surface 51aa and a flange portion 51b, which is formed by primary injection molding, and a light incident portion 52a and a flange portion 52b having a light incident surface 52aa. The second outer shell portion 52 is formed as a flange portion by secondary molding, and at the same time, the flange portions 51b and 52b of the first outer shell portion 51 and the second outer shell portion 52 are welded in an airtight manner. The welding flange portion 54 is provided.

  And while the hollow part 53 is formed by the 1st outer shell part 51 and the 2nd outer shell part 52, the resin injection path 55 and the gas vent path 56 used when filling the resin in the hollow part 53 in a post process are also provided. Is formed. In addition, the part shown with the code | symbol 57 is a gate trace at the time of secondary shaping | molding.

  In the post-molding process of the hollow lens 50, as shown in FIG. 12 (an explanatory diagram for injecting the filling resin into the hollow lens), the inside of the hollow portion 53 is extracted while the gas (air) is being removed through the gas vent passage 56. A filling resin (cross-linked acrylic resin having the same refractive index as the molding resin 3 used in the primary molding resin injection step and the secondary molding resin injection step) 6 is injected and filled via the resin injection path 55, and heated. Harden.

In this case, the crosslinked acrylic resin of the filling resin 6 has a viscosity of 100 cP and a temperature of the thermoplastic acrylic resin constituting the hollow lens 50 and having a temperature of 240 ° C. and a viscosity of 53 × 10 ⁶ cP at the time of injection molding. Using a low-viscosity and low-viscosity material of less than 110 ° C., the filled resin 6 having a viscosity close to water is formed in the hollow lens 50 formed of the molding resin 3 made of a thermoplastic acrylic resin, and bubbles are not generated. Inject into the hollow portion 53 so as not to occur.

  For example, FIG. 13 (an explanatory diagram showing a state in which a hollow lens is set in a resin injection jig) is provided so as not to damage the optical surface composed of the light incident surface 52aa and the lens surface 51aa when the filling resin 6 is injected. It is preferable to use a resin injection jig 65 that is supported and fixed by the flange portions 51b and 52b without contacting the light incident surface 52aa and the lens surface 51aa. Thereby, the filling resin 6 can be rapidly injected without damaging the light incident surface 52aa and the lens surface 51aa.

  As shown in FIG. 14 (longitudinal sectional view), the aspherical lens 70 in which the hollow portion 53 is filled with the filling resin 6 has the first outer shell portion 51 and the second outer shell portion 52 made of the same resin material. On the other hand, since the filling resin 6 is made of a resin material having the same refractive index, it is optically integrated without forming a boundary surface at each boundary. Therefore, it has an optical characteristic equivalent to that of an aspherical lens having the same shape and size formed by batch molding by injection molding.

  The broken line indicating the boundary between the first outer shell portion 51 and the filling resin 6 and the broken line indicating the boundary between the filling resin 6 and the second outer shell portion 52 shown in FIG. This is for convenience and does not actually exist.

By the way, the above-described aspherical lens (see FIG. 17) having a lens part diameter (D) of 58 mmφ, a maximum thickness (H _MAX ) of 19 mm, and a flange part thickness (H _F ) of 2.5 mm is used as a thermoplastic acrylic. A conventional manufacturing method in which the resin-only batch molding is performed, and the first outer shell portion 51 and the second outer shell portion 52 are molded with a thermoplastic acrylic resin, and the filling resin 6 is formed with a crosslinked acrylic resin. For the manufacturing method of the present invention having a three-layer structure of the outer shell portion 51, the filling resin 6, and the second outer shell portion 52, the tact time from the start to the end of the manufacture was calculated by simulation.

  As a result, in the conventional manufacturing method, the tact time was 960 seconds (16 minutes). On the other hand, in the manufacturing method of the present invention, the primary molding is 60 seconds, the subsequent mold opening, the mold slide and the mold clamping for secondary molding 10 seconds, the secondary molding 60 seconds, the subsequent mold opening, It took 15 seconds for the jig set for taking out the resin and filling the resin, and 60 seconds for the filling resin injection and cross-linking curing, resulting in a total of 205 seconds (3 minutes 25 seconds).

  Therefore, it was found that the manufacturing method of the present invention for an aspheric lens can manufacture a product with a tact time of about 22% with respect to the conventional manufacturing direction. In other words, the production efficiency is increased by about 4.6 times.

  In addition, it is not necessary to consider the occurrence of sink marks, which is a problem in the conventional batch molding, in the manufacturing method of the present invention, the mold design becomes easy and the degree of freedom in design increases, and the mold manufacturing cost also increases. It can be reduced and good optical characteristics can be obtained with certainty.

  As described above, the manufacturing method of the present invention can significantly improve productivity and reliably ensure optical reliability with respect to the conventional manufacturing method.

DESCRIPTION OF SYMBOLS 1 ... Injection mold 2 ... Parting line 3 ... Molding resin 5 ... Resin injection jig 6 ... Filling resin 10 ... Fixed metal mold 10a ... Butting surface 11 ... Nozzle touch part (molten resin injection port)
DESCRIPTION OF SYMBOLS 12 ... Valve gate 12a ... Gate 13 ... Gate 14 ... Core part 20 for welding flange part shaping | molding cavity ... 1st cavity 21 ... Lens part shaping | molding area | region 22 ... Flange part shaping | molding area | region 23 ... 2nd cavity 24 ... Light incident part shaping | molding area | region 25 ... Flange part forming region 26 ... Third cavity 30 ... Movable mold 30a ... Butt face 31 ... Hydraulic device 32 ... Gate cut pin 32a ... Tip part 33 ... Resin injection path forming core part 34 ... Gas venting path forming core part 50 ... Hollow lens 51 ... First outer shell part 51a ... Lens part 51aa ... Aspherical lens surface 51b ... Annular outer peripheral edge part (flange part)
52 ... 2nd outer shell part 52a ... Light incident part 52aa ... Light incident surface 52b ... Annular outer periphery part (flange part)
53 ... Hollow portion 54 ... Welding flange portion 55 ... Resin injection passage 56 ... Gas vent passage 57 ... Secondary molding gate mark 60 ... Cylinder 61 ... Nozzle 62 ... Screw 65 ... Resin injection jig 70 ... Aspherical lens

Claims (5)

A hollow lens having a hollow portion formed of a first outer shell portion made of a first resin member and a second outer shell portion made of a second resin member;
A filled resin composed of a third resin member filled in the hollow portion of the hollow lens,
The aspherical lens, wherein the first resin, the second resin, and the third resin all have the same refractive index. A fixed mold and a movable mold each having a core part and a cavity part are primary clamped to form a first mold by the core part of the fixed mold and the cavity part of the movable mold, and the fixed mold. A step of forming a second cavity between the cavity portion of the mold and the core portion of the movable mold;
Filling the first cavity and the second cavity with a molding resin by primary injection molding and molding the first molded product and the second molded product, respectively;
The movable mold is slid after the stationary mold and the movable mold are opened, and the second molded article of the stationary mold remains in the cavity portion where the first molded article of the movable mold remains. Forming a third cavity that is connected to the second molded product by clamping a secondary mold so as to face the cavity portion;
The third cavity is filled with a molding resin by secondary injection molding to form a third molded product integrated with the second molded product, and at the same time, the first molded product and the second molded product are hermetically welded. Process,
Opening the fixed mold and the movable mold and taking out a hollow lens having a hollow portion, which is constituted by the first molded product, the second molded product, and the third molded product;
Forming an aspherical lens by filling and filling a hollow portion of the hollow lens with a filling resin; and
A method for producing an aspheric lens, comprising:   3. The resin injection path serving as an injection path and a gas vent path serving as a gas vent path when the filling resin is poured into the hollow portion of the hollow lens by the primary injection molding. A manufacturing method of an aspherical lens given in 2.   The first cavity and the second cavity have different volumes and are connected via a gate. In the primary injection molding, the cavity with the smaller volume is filled with the molding resin and the cavity with the larger volume is being filled. In addition, before the molding resin filled in the cavity having the smaller volume is solidified, a gate cut pin protrudes from the gate to separate the first cavity and the second cavity in the mold. A manufacturing method of the aspherical lens according to claim 2 or 3.   The molding resin is a thermoplastic resin, the filling resin is a cross-linked resin, and the molding resin and the filling resin are made of a resin material having the same refractive index. The manufacturing method of the aspherical lens of description.

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