WO2009122819A1

WO2009122819A1 - Optical element shaping mold, and optical element manufacturing method

Info

Publication number: WO2009122819A1
Application number: PCT/JP2009/053185
Authority: WO
Inventors: 省吾山本
Original assignee: コニカミノルタオプト株式会社
Priority date: 2008-03-31
Filing date: 2009-02-23
Publication date: 2009-10-08
Also published as: JPWO2009122819A1; CN101980847A

Abstract

Provided is an optical element shaping mold, which can release air efficiently from the inside of a molding space and which can eliminate burrs after an optical element is molded. In the injection molding of the optical element, the optical element shaping mold (40) is equipped at a portion of a gate portion (GP) thereof with an air intake port (44o) for releasing the air from the inside of a mold space (CV), so that the air in the mold space (CV) can be efficiently released through the air intake port (44o), thereby to evacuate the mold space (CV) to a desired degree. As a result, the mold space (CV) can be filled with a resin while preventing the air reservation, so that the resin can be molded into a lens (OL) of high precision. Moreover, the molded lens (OL) can eliminate the excessive burrs and can prevent the garbage, which might otherwise be caused by the interference with other parts or by the falling.

Description

Optical element molding die and optical element manufacturing method

The present invention relates to an optical element molding die and an optical element manufacturing method using the same.

As a method for manufacturing an optical element, there is a method in which a resin is injected into a mold space (cavity) formed by a first mold and a second mold and is molded. As an optical element molding die used in this method of manufacturing an optical element, there is an optical element molding die provided with holes and grooves (air vents) for venting air in the mold space (see, for example, Patent Document 1). Also, there is a type in which a deaeration hole is provided at a position corresponding to the optical axis of the optical function part of the optical element or in the vicinity thereof so that air in the mold space is deaerated at the time of resin injection (for example, Patent Document 2). Accordingly, the inside of the mold space is decompressed immediately before the resin is filled into the mold space, and the generation of residual bubbles can be reduced.
JP 2004-264538 A JP 2004-130703 A

However, in the optical element molding die as in Patent Document 1, in the objective lens for optical pickup, in the case of an objective lens having a large curvature for BD (Blu-ray Disc) with NA of 0.6 or more, particularly NA of 0.8 or more, Problems such as poor air escape in the mold space and air trapping at the apex of the surface with a large curvature cause the optical surface of the optical element not to be transferred or the appearance of the optical element to deteriorate, resulting in a decrease in the optical function of the optical element. There is. In addition, since a slight amount of resin enters the holes and grooves to form convex burrs, there is a problem in that the burrs come into contact with other parts or become dust. Even in the optical element molding die as in Patent Document 2, an air vent hole is provided at the center of the mirror surface core where air easily collects, as in the above optical element mold, but resin enters the air vent hole. Therefore, there is a problem that the burr comes into contact with another part or is taken out and becomes garbage.

Therefore, an object of the present invention is to provide an optical element molding die that can efficiently evacuate the air in the mold space and prevent the occurrence of burrs after molding the optical element.

Another object of the present invention is to provide a method for manufacturing an optical element using the optical element molding die as described above.

An optical element molding die according to the present invention is an optical element molding die that molds an optical element with a first mold and a second mold, and is formed by closing the first mold and the second mold. It is characterized by having a structure for venting air in the mold space so as to face a part of the flow path for resin inflow communicating with the mold space.

In the optical element molding die, in the injection molding of the optical element, a structure for extracting the air in the mold space is provided in a part of the flow path for resin inflow, so that the air in the mold space is passed through the structure. Thus, the mold space can be decompressed to a desired level. Therefore, the resin can be filled in the mold space while preventing air accumulation, and a highly accurate optical element can be molded. In addition, it is possible to prevent excessive burrs from being generated in the molded optical element, and it is possible to prevent generation of dust due to interference with other parts or dropping off.

In a specific aspect or viewpoint of the present invention, the first mold is a fixed mold, and the second mold is a movable mold. In addition, resin is normally inject | poured from the fixed mold side, and is guide | induced to a flow path.

In another aspect of the present invention, the structure is provided in at least one of the first mold and the second mold. In this case, it can be a type incorporated in one mold.

In still another aspect of the present invention, the flow path is any one of a gate, a sprue, and a runner. The injected resin usually reaches the mold space through the sprue, runner, and gate.

In still another aspect of the present invention, the structure is an air suction port opened in the flow path. In this case, air can be efficiently extracted from the air suction port.

Still another aspect of the present invention is characterized by further comprising an opening / closing device for opening / closing the air suction port. In this case, the opening and closing of the air suction port can be controlled according to the manufacturing process. Moreover, it is possible to prevent the formation of burrs due to the inflow of resin into the air suction port.

In still another aspect of the present invention, the air suction port is a gap-like groove. In this case, the inflow of resin to the air suction port can be prevented and air can be extracted efficiently.

The optical element manufacturing method according to the present invention is molded using an optical element molding die that forms a resin inflow channel and an optical element mold space by closing the first mold and the second mold. A method of manufacturing an optical element, wherein after forming a mold space by closing the mold, a first step of venting the mold space through a part of the flow path, and a pressure reduction by the first process through the flow path And a second step of filling the mold space with the resin.

In the optical element manufacturing method, in the injection molding of the optical element, the resin is filled in the mold space while preventing air accumulation by removing air through a part of the flow path for resin inflow before filling the resin. It is possible to mold an optical element with high accuracy. In addition, it is possible to prevent excessive burrs from being generated in the molded optical element, and it is possible to prevent generation of dust due to interference with other parts or dropping off.

In a specific aspect of the present invention, the optical element molding die is characterized in that at least one of the first die and the second die has a structure for extracting air in the die space.

Another aspect of the present invention is characterized in that, as the first step, before the resin flows into the flow path, the inside of the mold space is decompressed by extracting the air in the mold space. In this case, the resin can be filled into the mold space while preventing air accumulation by reducing the pressure in the mold space before starting the inflow of the resin into the flow path.

In still another aspect of the present invention, as a first step, the mold space is evacuated by extracting the air in the mold space before filling the resin in the space up to the structure in the flow path. Features. In this case, by reducing the pressure in the mold space before the resin is filled up to the above structure, the resin can be filled in the mold space while preventing air accumulation.

In still another aspect of the present invention, the air in the mold space is always removed in the first step and the second step. In this case, by constantly reducing the pressure in the mold space, it is possible to fill the mold space with resin while preventing air accumulation.

It is sectional drawing explaining the structure of the optical element shaping die of 1st Embodiment. It is an expanded sectional view of the optical element shaping die of FIG. It is sectional drawing of the lens shape | molded by the optical element shaping die of FIG. It is a front view explaining the structure of an injection molding machine notionally. (A)-(C) are the figures explaining the timing of the pressure reduction process and filling process of the injection molding machine of a 1st embodiment. It is a figure explaining the optical element shaping die of a 2nd embodiment. (A)-(C) is a figure explaining the timing of the pressure reduction process and filling process of the injection molding machine of 2nd Embodiment. It is a figure which shows the modification of the optical element shaping die of FIG. It is a figure which shows another modification of the optical element shaping die of FIG. It is a figure which shows the modification of optical element shaping molds, such as FIG. It is a figure which shows another modification of optical element shaping molds, such as FIG. (A) to (C) are diagrams showing modified examples of the timing of the decompression step and the filling step in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Injection molding machine 11 ... Fixed platen 12 ... Movable platen 15 ... Opening / closing drive device 16 ... Injection device 17 ... Temperature control device 18 ... Depressurization device 41 ... Fixed metal mold 42 ... Movable metal mold 44o, 144o, 244o, 344o ... Air Suction port 45 ... Suction port opening / closing mechanism CV ... Mold space GP ... Gate part RP ... Runner part SP ... Sprue part OL ... Lens

[First Embodiment]
Hereinafter, an optical element molding die and an optical element manufacturing method according to a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view for explaining the structure of an optical element molding die 40 composed of a fixed die 41 and a movable die 42, and FIG. 2 is an enlarged cross-sectional view of a P1 portion in FIG. FIG. 3 is a cross-sectional view of a lens OL molded by the optical element molding die 40 shown in FIG.

The optical element molding die 40 of this embodiment includes a fixed die 41 and a movable die 42. The fixed mold 41 and the movable mold 42 can be opened and closed with the parting line PL as a boundary. By performing mold clamping with the fixed mold 41 and the movable mold 42, mold spaces CV for molding the lens OL as the optical element shown in FIG. 3 are formed, and each mold space CV is formed. A flow path portion FC for supplying the resin to is formed. The mold space CV includes a main body space CV1 sandwiched between a pair of optical transfer surfaces S1 and S2, which will be described later, and a flange space CV2 surrounded by a pair of peripheral transfer surfaces S3 and S4. The flow path portion FC is composed of a sprue portion SP, a runner portion RP, and a gate portion GP. Although omitted in the drawing, the molded product injection-molded by the optical element molding die 40 includes a plurality of lenses OL, and the resin filling space corresponding to the molded product is formed from the sprue portion SP. The runner portion RP is branched into a plurality of portions, and the mold space CV communicates with the leading end portion of each branched runner portion RP via the gate portion GP.

As shown in FIG. 2, the fixed mold 41 has a circular optical transfer surface S1 corresponding to the optical surface OS1 of the lens OL and a flange portion FL1 of the lens OL on the mold surface facing the movable mold 42. , An annular peripheral transfer surface S3 that surrounds the outer periphery of the optical transfer surface S1, a gate recess S5 that corresponds to the gate portion GP, and a runner recess that corresponds to the runner portion RP. S7. Further, a sprue portion SP for injecting resin is formed in the center of the fixed mold 41 (see FIG. 1).

As in the case of the fixed mold 41, the movable mold 42 has a circular optical transfer surface S2 that is a portion corresponding to the optical surface OS2 of the lens OL on the mold surface facing the fixed mold 41, and the lens OL. A portion corresponding to the flange portion FL2, an annular peripheral transfer surface S4 surrounding the outer periphery of the optical transfer surface S2, a gate recess S6 corresponding to the gate portion GP, and a portion corresponding to the runner portion RP. And a certain runner recess S8.

As shown in FIG. 1, the movable mold 42 further includes an O-ring 43, an air suction port 44o, and a suction port opening / closing mechanism 45.

The O-ring 43 is provided outside the mold surface of the movable mold 42 so as to surround the optical transfer surface S2 and the like. The O-ring 43 is substantially annular and is fitted in a circumferential groove 42 a provided in the movable mold 42. Here, the O-ring 43 is made of a material that can maintain airtightness in the mold space CV and does not generate gas. As the O-ring 43, for example, a fluororesin is preferably used.

The air suction port 44o has a structure for extracting air from the mold space CV, and is provided in a part of the gate part GP which is a flow path for resin inflow. As shown in FIG. 2, the air suction port 44o is a part that allows the gate part GP to communicate with the vent pipe 44b. The ventilation pipe 44b extends from an opening 44a adjacent to the air suction port 44o to an opening 44c provided outside the movable mold 42. A decompression device 18 to be described later is connected to the outer opening 44c. By operating the decompression device 18, the air in the mold space CV is sucked.

The suction port opening / closing mechanism 45 is a mechanism for opening and closing the air suction port 44o, and includes a suction port opening / closing part 45a and an opening / closing drive part 45b. The suction port opening / closing part 45a is a plug-like member having a small-diameter part 45t having an outer diameter that matches the inner diameter of the opening part 44a, which is the end of the air suction port 44o on the gate part GP side, and is driven by the opening / closing drive part 45b. It has been possible to advance and retreat. The opening / closing drive unit 45b opens / closes the opening 44a by moving the suction port opening / closing unit 45a forward and backward in accordance with the timing of the resin inflow into the mold space CV, and causing the small diameter portion 45t to function like a valve. When the suction opening / closing part 45a is closed by the opening / closing drive part 45b, the suction port opening / closing part 45a is pressurized to the tip side with a force equal to or higher than the resin pressure, and the small diameter part 45t of the suction opening / closing part 45a and the opening 44a are in close contact with each other. Thus, the gate portion GP and the vent pipe 44b are blocked.

FIG. 4 is a front view for explaining a part of the injection molding machine 10 for carrying out the optical element manufacturing method of the present embodiment. The injection molding machine 10 includes an optical element molding die 40 shown in FIG. 1 and the like, and injection molding is performed by injecting a resin into the optical element molding die 40 to produce a molded product.

The injection molding machine 10 includes a fixed platen 11, a movable platen 12, an opening / closing drive device 15, an injection device 16, a temperature adjustment device 17, and a decompression device 18. The injection molding machine 10 sandwiches both

molds

41 and 42 by sandwiching a fixed mold 41 as a first mold and a movable mold 42 as a second mold between the movable platen 12 and the fixed platen 11. Molding is possible by clamping. Here, in the injection molding machine 10, mold opening and mold closing are in the horizontal direction. An injection molding machine that opens and closes the mold in the vertical direction may be used.

The fixed platen 11 is fixed to the upper surface on the center side of the support frame 14, and the inside of the fixed platen 11 detachably supports the fixed mold 41. The movable platen 12 is supported by an opening / closing drive device 15 to be described later so as to be movable forward and backward with respect to the fixed platen 11. Inside the movable platen 12, a movable mold 42 is detachably supported. The opening / closing drive device 15 supports the movable platen 12 and enables a smooth reciprocating movement in the advancing / retreating direction of the movable platen 12 with respect to the fixed platen 11. As a result, the movable platen 12 can be freely displaced toward and away from the fixed platen 11, and as a result, the movable platen 12 and the fixed platen 11 can be closed so as to be close to each other, Both can be clamped with a desired clamping force.

The injection device 16 includes a cylinder 16a, a raw material reservoir 16b, a screw 16c, and a resin injection end 16d. The injection device 16 can discharge the molten resin from the resin injection end 16d in a state in which the temperature is controlled to be higher than the mold temperature. The injection device 16 can detachably connect the resin injection end 16d of the cylinder 16a to the sprue portion SP (see FIG. 1) of the fixed platen 11, and is movable with the fixed mold 41 via the fixed platen 11. Molten resin can be supplied at a desired timing into a mold space CV (see FIG. 1) formed with the mold 42 clamped.

The temperature adjusting device 17 is a part that adjusts the temperature of the

molds

41 and 42 of the injection molding machine 10. The temperature adjustment device 17 has a temperature adjustment circuit, and the temperature of the fixed mold 41 and the movable mold 42 can be adjusted. Specifically, for example, the fixed mold 41 and the movable mold 42 are heated to a necessary temperature by supplying a temperature adjusting medium to a fluid circulation path provided in the fixed platen 11 and the movable platen 12. The temperature may be adjusted using a heater or the like without using a medium.

The decompression device 18 is a part that evacuates the mold space CV of the injection molding machine 10. The decompression device 18 includes a vacuum pump 18 a that enables decompression of the mold space CV formed by the fixed mold 41 and the movable mold 42. The vacuum pump 18a is connected to an opening 44c provided in the movable mold 42, and air in the mold space CV can be extracted from the opening 44c (see FIG. 1).

Hereinafter, a method for manufacturing the optical element of the present embodiment will be described. FIG. 5 is a diagram for explaining the timing of the decompression process and the filling process during the mold clamping operation of the injection molding machine 10. FIG. 5A is a diagram showing the timing of the mold clamping operation, FIG. 5B is a diagram showing the timing of venting air in the mold space CV, and FIG. 5C is the flow path portion FC. It is a figure which shows the timing of the resin injection | pouring to.

First, the temperature control device 17 is operated to heat both

molds

41 and 42 to a temperature suitable for molding.

Next, the opening / closing drive device 15 is operated to advance the movable platen 12 to start mold closing. By continuing the mold closing operation of the opening / closing drive device 15, the movable platen 12 moves to the fixed platen 11 side to the die contact position where the fixed die 41 and the movable die 42 come into contact with each other, and the die closing is completed. By further continuing the mold closing operation of the driving device 15, mold clamping for clamping the fixed mold 41 and the movable mold 42 with necessary pressure is performed as shown in FIG.

After the mold clamping, as shown in FIG. 5 (B), a depressurizing step is performed to extract air from the mold space CV through the air suction port 44o. That is, the suction port opening / closing part 45a is retracted via the opening / closing drive part 45b, the small diameter part 45t at the tip is separated from the opening part 44a, the opening part 44a is in a vented state, and flows through the ventilation pipe 44b and the opening part 44c. Air in the channel portion FC and the mold space CV is sucked by the vacuum pump 18a, and the flow channel portion FC and the mold space CV are depressurized to a desired degree of vacuum. At this time, the resin injection end 16d comes into contact with the right end portion FCa of the flow path portion FC in FIG. 1 with a predetermined pressure in a state where the molten resin has entered the resin injection end 16d of the injection device 16 in advance. And kept airtight. As a result, the flow path portion FC, the mold space CV, and the air suction port 44o connected to the vacuum pump 18a are closed as a whole, so that the spaces FC, CV, 44o can be decompressed. Yes. After the mold space CV is depressurized by a certain amount in this way, the small diameter portion 45t of the suction port opening / closing portion 45a on the back side of the flow path portion FC, that is, the upper side or the lower side in FIG. As a result, the opening 44a is closed and the decompression step is completed.

After the decompression step, the injection device 16 is operated as shown in FIG. 5C, and the molten resin is injected and injected at a required pressure through the flow path portion FC. As a result, a filling process is performed in which the mold space CV between the clamped fixed mold 41 and the movable mold 42 is filled with resin.

After the filling process, the injection molding machine 10 keeps the resin pressure in the mold space CV at a required level. At this time, the mold space CV and the flow path portion FC are appropriately heated by the temperature adjusting device 17, and the molten resin supplied from the injection device 16 is slowly cooled, and the molten resin is solidified with the cooling. Wait for the molding to complete.

After completion of molding, the mold clamping is finished, and the opening / closing drive device 15 is operated to perform mold opening for moving the movable platen 12 backward. Along with this, the movable mold 42 moves backward, and the fixed mold 41 and the movable mold 42 are separated. As a result, the molded product, that is, the lens OL is released from the fixed mold 41 while being held by the movable mold 42.

Finally, the ejector or the like (not shown) is operated to release the lens OL, and the take-out device (not shown) is operated to carry the molded product including the lens OL out of the molding apparatus.

According to the optical element molding die and the optical element manufacturing method described above, the air suction port 44o for venting the air in the mold space CV is provided in a part of the gate portion GP of the optical element molding die 40. The air in the mold space CV can be efficiently extracted through the air suction port 44o. Since the inside of the mold space CV can be efficiently depressurized before the resin flows in, the resin can be filled into the mold space CV while preventing air accumulation, and a highly accurate lens OL can be molded. In addition, since air is extracted from the portion that does not affect the optical function of the lens OL, it is possible to prevent extra burrs from being generated in the molded lens OL, and to generate dust due to interference with other parts or dropping off. Can be prevented.

Further, by allowing the air suction port 44o to be opened and closed by the suction port opening / closing mechanism 45, the opening and closing of the air suction port 44o can be controlled according to the manufacturing process. Further, the outer diameter of the small diameter portion of the suction port opening / closing portion 45a is fitted to the inner diameter of the opening portion 44a of the air suction port 44o, thereby preventing a large gap from being generated between the opening portion 44a and the gate portion GP. And generation of large burrs can be suppressed.

As described above, for example, when a lens having a large curvature such as a BD lens or an HD-DVD lens is manufactured, transferability of the optical surface can be improved. The same applies to the manufacture of an optical element having an optical path difference providing structure and a small-diameter optical element.

[Second Embodiment]
Hereinafter, an optical element molding die and an optical element manufacturing method according to the second embodiment will be described. The optical element molding die and the optical element manufacturing method according to the second embodiment are modifications of the first embodiment, and parts that are not particularly described are the same as those of the first embodiment. .

FIG. 6A is an enlarged cross-sectional view of the periphery of the mold space CV of the optical element molding die 140 composed of the fixed die 41 and the movable die 42 as viewed from the parting line PL surface side of the movable die 42. FIG. 6B is a cross-sectional view along the line AA.

In the second embodiment, the movable mold 42 is provided with a gap-shaped groove 144d in the air suction port 144o instead of including the suction port opening / closing mechanism 45 shown in FIGS. The groove 144d is formed by providing a concave portion having a minute depth in the movable mold 42 and clamping the fixed mold 41 and the movable mold 42 together. A space 144e is provided between the groove 144d and the vent pipe 144b, so that air can be efficiently sucked in while minimizing the influence of pressure loss. The groove 144d is a gap of about 5 to 100 μm, for example, and can suck air while preventing the resin from flowing into the space 144e from the air suction port 144o. In the figure, the groove 144d is provided in the gate portion GP, but it may be provided in the runner portion RP.

Hereinafter, a method for manufacturing the optical element of the present embodiment will be described. FIG. 7 is a diagram for explaining the timing of the pressure reducing process and the resin filling process during the mold clamping operation of the injection molding machine 10.

As shown in FIG. 7 (B), from the start to the end of mold clamping, a depressurization process is performed to extract air from the mold space CV through the air suction port 144o. That is, the air in the flow path portion FC and the mold space CV is sucked by the vacuum pump 18a from the opening 144a through the groove 144d, the vent pipe 144b, and the opening 144c, so that the flow path portion FC and the mold space CV are desired. The degree of vacuum is reduced.

After the mold space CV is depressurized by a certain amount, as shown in FIG. 7C, the mold space CV between the clamped fixed mold 41 and the movable mold 42 is filled with resin. A process is performed. Even during the filling process, the pressure reducing process is performed, and the air in the flow path portion FC and the mold space CV is sucked.

According to the optical element molding die and the optical element manufacturing method described above, by providing the air suction port 144o with the gap-shaped groove 144d, it is possible to prevent the resin from flowing into the air suction port 144o and prevent the resin from flowing into the mold space CV. Air can be extracted efficiently. Further, since the decompression process can be performed during the filling process, the resin can be filled into the mold space CV while preventing air accumulation, and the lens OL with high accuracy can be molded. In addition, since air is extracted from the portion that does not affect the optical function of the lens OL, it is possible to prevent extra burrs from being generated in the molded lens OL, and to generate dust due to interference with other parts or dropping off. Can be prevented.

As shown in FIG. 8, a small hole 244d may be provided in the movable mold 42 as a part of the air suction port 244o. Further, as shown in FIG. 9, the inflow of resin into the air suction port 344o may be prevented by inserting a porous member 344f having minute holes into the air suction port 344o.

Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments, and various modifications are possible. For example, although the air suction port 44o and the like are provided in the gate portion GP, they may be provided in the sprue portion SP as shown in FIG. 10 or in the runner portion RP as shown in FIG. Further, the air suction port 44o or the like may be provided in either the fixed mold 41 or the movable mold 42.

Further, at the timing of the pressure reducing process and the resin filling process during the mold clamping operation of the injection molding machine 10 described in the present embodiment, the pressure reducing process is performed in the vicinity of the opening 44a adjacent to the air suction port 44o as shown in FIG. You may carry out until it is filled. In the second embodiment, the decompression step described in FIG. 5 may be performed.

Further, in the above embodiment, a method may be used in which the resin is filled while releasing the air in the mold space CV through the air suction ports 44o, 144o, 244o without performing vacuuming at the time of injection molding.

In the above embodiment, if the positions of the air suction ports 44o and the like are portions other than the mold space CV, an appropriate number can be provided at an appropriate position. Further, the shape of the vent pipe 44b and the like for ventilating the air suction port 44o and the like to the outside of the mold can be freely deformed.

In the above embodiment, the structure of the air suction ports 44o, 144o, 244o, 344o is not limited to that described in the above embodiment, and the resin does not flow into the air suction ports 44o, 144o, 244o, 344o. I just need it.

In the above embodiment, the shape of the mold space CV provided in the optical element molding dies 40, 140, 240, 340 composed of the fixed mold 41 and the movable mold 42 is not limited to the illustrated one, but various It can be a shape. That is, the shape of the mold space CV is merely an example, and can be appropriately changed according to the use of the lens OL.

In the above embodiment, the injection molding machine 10 may be, for example, a hydraulic type or an electric type as long as it can open and close the optical element molding dies 40, 140, 240, and 340.

Claims

An optical element molding die for molding an optical element with a first mold and a second mold,
A structure for venting air in the mold space is provided so as to face a part of a flow path for resin inflow communicating with a mold space formed by closing the mold of the first mold and the second mold. An optical element molding die characterized by the above.
The optical element molding die according to claim 1, wherein the first die is a fixed die, and the second die is a movable die.
3. The optical element molding die according to claim 1 or 2, wherein the structure is provided in at least one of the first die and the second die.
The optical element molding die according to any one of claims 1 to 3, wherein the flow path is one of a gate, a sprue, and a runner.
The optical element molding die according to any one of claims 1 to 4, wherein the structure is an air suction port opened in the flow path.
The optical element molding die according to claim 5, further comprising an opening / closing device that opens and closes the air suction port.
The optical element molding die according to claim 5, wherein the air suction port is a gap-like groove.
A method of manufacturing an optical element that performs molding using an optical element molding mold that forms a flow path for resin inflow and a mold space for an optical element by closing a mold of a first mold and a second mold,
A first step of venting the mold space through a part of the flow path after forming the mold space by the mold closing;
A second step of filling the mold space in a state where the pressure is reduced by the first step through the flow path;
An optical element manufacturing method comprising:
9. The optical element molding die according to claim 8, wherein at least one of the first die and the second die has a structure for venting air in the die space. Of manufacturing the optical element.
The range of claim 8 or 9, wherein, as the first step, before the resin flows into the flow path, the inside of the mold space is decompressed by removing the air in the mold space. The manufacturing method of the optical element of description.
The first step is characterized in that the mold space is depressurized by removing the air in the mold space until the space up to the structure in the flow path is filled with resin. 10. A method for manufacturing an optical element according to item 8 or 9 in the range.
10. The method for manufacturing an optical element according to claim 8, wherein in the first step and the second step, the air in the mold space is constantly vented.