JP5464975B2 - Optical element manufacturing method and optical element manufacturing apparatus - Google Patents

Description

  The present invention relates to an optical element manufacturing method and an optical element manufacturing apparatus for manufacturing an optical element while sequentially transferring a mold set containing an optical material.

  Conventionally, when molding an optical element such as a glass lens using a molding die, the linear expansion coefficient of the optical material is larger than the linear expansion coefficient of the molding die, so in the cooling process after pressing the optical material, By inhibiting the shrinkage of the optical material, stress may be generated in the optical material, which may cause a defect such as a crack or a crack in the optical material.

  Therefore, in the optical element molding method described in Patent Document 1, a tensile force is applied to the mold by starting to pull the mold in a direction away from the glass from the vicinity where the glass temperature is lowered to the transition point in the cooling step. A technique is employed in which the glass is released from the mold by differentiating the mold temperatures of the pair of upper and lower molds.

  In the optical element molding method described in Patent Document 1, a tensile force is applied to the mold by pulling a flange provided on the mold in the vertical direction with a mold fixture fixed to the movable shaft.

Japanese Patent No. 3939157

  By the way, when manufacturing an optical element while accommodating an optical material in a mold set and sequentially transferring the mold set, the mold is pulled using a movable shaft as in the optical element molding method described in Patent Document 1. The technique cannot be adopted because the mold set cannot be transported.

  An object of the present invention is to provide an optical element manufacturing method and an optical element capable of preventing a defect from occurring in an optical material at the time of contraction even when an optical element is manufactured while sequentially transferring a mold set containing the optical material. It is to provide a manufacturing apparatus.

  The optical element manufacturing method of the present invention includes a heating and softening step of softening the optical material by heating in the optical element manufacturing method of manufacturing an optical element while sequentially transferring a mold set containing an optical material, and the mold set. A pressing step of pressing the optical material softened by pressing the molding die included in, and a suction step of releasing the optical material from the molding die by sucking the pressed molding die.

  In the method of manufacturing an optical element, the mold set is a movable mold that is a mold that is movably disposed in the mold set and pressed in the pressing step, and a sleeve that is disposed on the outer periphery of the movable mold. In the suction step, the movement is performed by sucking the movable mold through a space defined by the movable mold, the sleeve, and a mounting plate on which the mold set is mounted. The optical material may be released from the mold.

In the method for manufacturing an optical element, the suction step may be performed in the process of cooling the optical material.
The optical element manufacturing method may further include a blowing step that is performed after the pressing step and before the suction step and that cools the molding die by blowing gas to the pressed molding die. It is good to.

  In the optical element manufacturing method, the mold set is disposed so as to be movable in the mold set, and is disposed opposite to the movable mold, which is a molding mold that is pressed in the pressing step. It is preferable that the movable mold includes a convex molding surface, and the fixed mold includes a concave molding surface or a flat molding surface.

  In the method for manufacturing an optical element, the mold set is disposed so as to be movable in the mold set and is disposed opposite to the movable mold, which is a molding mold that is pressed in the pressing step. The movable mold and the fixed mold include a convex molding surface, and the curvature radius of the convex molding surface of the movable mold is smaller than the curvature radius of the convex molding surface of the fixed mold. Good.

  An optical element manufacturing apparatus according to the present invention includes an optical element manufacturing apparatus that manufactures an optical element while sequentially transferring a mold set containing an optical material, and a heating unit that softens the optical material by heating, and the mold set includes: A press unit that presses the optical material that has been softened by pressing the forming die, and a suction mechanism that releases the optical material from the forming die by sucking the pressed mold.

The optical element manufacturing apparatus may further include a blow mechanism for blowing gas to the molding die pressed by the press portion.
In the optical element manufacturing apparatus, the gas flow path to be blown may be formed in the press section, and the blow mechanism may be the flow path.
The optical element manufacturing apparatus may further include a press stage that presses the optical material by the pressing unit, and a cooling stage that cools the optical material, and the suction mechanism is provided on the cooling stage. It is good to do.

  ADVANTAGE OF THE INVENTION According to this invention, even when manufacturing an optical element, transferring the mold set which accommodates an optical material sequentially, it can prevent that a defect arises in the optical material at the time of shrinkage | contraction.

It is sectional drawing which shows the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is principal part sectional drawing (the 1) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is principal part sectional drawing (the 2) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is principal part sectional drawing (the 3) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is principal part sectional drawing (the 4) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is principal part sectional drawing (the 5) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is principal part sectional drawing (the 6) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 1st Embodiment of this invention. It is sectional drawing which shows the manufacturing apparatus of the optical element which concerns on 2nd Embodiment of this invention. It is principal part sectional drawing (the 1) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 2nd Embodiment of this invention. It is principal part sectional drawing (the 2) which shows the press stage of the manufacturing apparatus of the optical element which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the manufacturing apparatus of the optical element which concerns on 3rd Embodiment of this invention. It is principal part sectional drawing (the 1) which shows the cooling stage of the manufacturing apparatus of the optical element which concerns on 3rd Embodiment of this invention. It is principal part sectional drawing (the 2) which shows the cooling stage of the manufacturing apparatus of the optical element which concerns on 3rd Embodiment of this invention. It is principal part sectional drawing (the 3) which shows the cooling stage of the manufacturing apparatus of the optical element which concerns on 3rd Embodiment of this invention.

Hereinafter, an optical element manufacturing method and an optical element manufacturing apparatus according to first to third embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>

FIG. 1 is a sectional view showing an optical element manufacturing apparatus 11 according to a first embodiment of the present invention.
2A to 2F are cross-sectional views of the main part showing the press stage 12 of the optical element manufacturing apparatus 11.

  An optical element manufacturing apparatus (hereinafter simply referred to as “manufacturing apparatus”) 11 includes a press stage 12, a cooling stage 13, a molding chamber 14, an input-side shutter 15, and a discharge-side shutter 16. It is a circulation type manufacturing apparatus that manufactures an optical element that is, for example, a glass lens while sequentially transferring the mold set 20.

  As shown in FIGS. 2A to 2F, the mold set 20 includes an upper mold 21 (first mold) that is a fixed mold and a lower mold 22 (second mold) that is a movable mold, as a plurality of molds. ), A holding member 23, an outer diameter frame 24, and a sleeve 25. The mold set 20 is made of, for example, tungsten carbide (WC).

  The upper mold 21 is formed with a flange portion 21b that extends in the outer circumferential direction at the upper portion of the base portion 21a. A concave molding surface 21c for transferring the convex shape to the optical material 31 is formed at the lower end of the base 21a.

  The lower mold 22 is disposed to face the upper mold 21. The lower mold 22 is provided with a convex portion 22b at the center of the upper portion of the base portion 22a and having a smaller diameter than the base portion 22a and protruding upward from the base portion 22a. A convex molding surface 22c for transferring the concave shape to the optical material 31 is formed at the upper end of the convex portion 22b.

  The holding member 23 has a cylindrical shape in which a flange portion 23a having a diameter larger than that of the base portion 22a of the lower mold 22 is formed in the lower portion. In the hollow portion 23b of the holding member 23, the convex portion 22b of the lower mold 22 is slidably inserted from below. The upper end surface 23 c of the holding member 23 is formed in a planar shape so as to transfer the planar shape to the outer periphery of the concave surface of the optical material 31.

  The outer diameter frame 24 has a cylindrical shape and is disposed between the upper mold 21 and the flange portion 23 a of the holding member 23. The outer diameter frame 24 transfers the curved surface shape to the outer peripheral side surface of the optical material 31 at a portion of the inner peripheral surface protruding upward from the holding member 23.

  The sleeve 25 has a cylindrical shape. Since the lower portion of the sleeve 25 is a thick portion 25a and the upper portion is a thin portion 25b, a step portion 25c is formed on the inner peripheral surface between the thick portion 25a and the thin portion 25b. The flange portion 23a of the holding member 23 is placed on the step portion 25c.

  The sleeve 25 is positioned on the outer periphery of the lower die 22, the holding member 23, and the outer diameter frame 24. The lower die 22 is on the inner peripheral surface of the thick portion 25a, and the holding member 23 and the outer diameter frame 24 are thin. The inner peripheral surface of the part 25b is slidable. In the upper mold 21, the base portion 21 a is inserted into the sleeve 25 from above, and the bottom surface of the flange portion 21 b is in contact with the upper end of the sleeve 25. For this reason, the lower mold 22 is arranged so as to be movable up and down in the mold set 20, while the upper mold 21 is in contact with the upper end of the sleeve 25 because the flange portion 21 b contacts the upper end of the sleeve 25. On the material 31 side, it is a fixed type that cannot be moved.

  As shown in FIG. 1, the press stage 12 and the cooling stage 13 include a lower plate (mounting plate) 12a, a lower plate 13a, base portions 12b and 13b, upper plates 12c and 13c, and cylinders 12d and 13d, respectively. And having.

The press stage 12 and the cooling stage 13 are disposed in the molding chamber 14 except for the cylinders 12d and 13d.
The press stage 12 includes a press shaft 12e (press portion) and a press shaft drive portion 12k (press portion drive portion). Further, as will be described in detail later, a suction tube 17 is connected to the press stage 12.

The lower plates 12a and 13a are installed on the base portions 12b and 13b, and two heaters 12f and 13f (heating portions) are arranged inside each.
The upper plates 12c and 13c are connected to the lifting shafts of the cylinders 12d and 13d, and move up and down to a position where they abut against the upper mold 21 of the mold set 20 and a position where the mold set 20 can be transferred by retreating upward therefrom To do. Two heaters 12g and 13g (heating units) are arranged inside the upper plates 12c and 13c.

  In the lower plate 12a of the press stage 12, a through hole (suction mechanism) 12h that penetrates the press shaft 12e in the vertical direction and forms a suction path of the suction pump 18 around the press shaft 12e is formed in the center. The press shaft 12e moves up and down by a press shaft driving unit 12k that is a cylinder, for example. The protruding amount from the lower plate 12a of the press shaft 12e is measured by a scale (not shown), and a control unit (not shown) drives and controls the press shaft driving unit 12k based on the measured protruding amount.

  The base portion 12b of the press stage 12 is formed with a through hole (suction mechanism) 12i that communicates with the through hole 12h of the lower plate 12a and penetrates the press shaft 12e vertically. The upper portion of the through hole 12i has a large diameter so as to form a suction path around the press shaft 12e, and the lower portion has a small diameter so that the press shaft 12e can slide. A suction path (suction mechanism) 12j communicating with the through hole 12i is formed in the upper part of the through hole 12i, and a suction pipe 17 is connected to the outside of the suction path 12j.

  The suction pump 18 is partitioned by the suction pipe 17, the suction path 12j and the through hole 12i of the base portion 12b, the through hole 12h of the lower plate 12a, the lower mold 22 and the sleeve 25 of the mold set 20, and the lower plate 12a. The lower die 22 is sucked downward through the space S.

  In the molding chamber 14, an inlet 14 a and an outlet 14 b for the mold set 20 are formed. The closing shutter 15 moves up and down to a position that closes the closing opening 14a and secures the airtightness of the molding chamber 14 and a position that retreats upward from there and allows the mold set 20 to pass. Similarly, the discharge-side shutter 16 moves up and down between a position where the discharge port 14b is closed and the airtightness of the molding chamber 14 is secured, and a position where the mold set 20 is allowed to retreat upward.

Hereinafter, a method for manufacturing an optical element using the manufacturing apparatus 11 will be described. In addition, the operation | movement later mentioned of the manufacturing apparatus 11 is controlled by the control part which is not shown in figure.
First, as shown in FIG. 2A, for example, a ball-shaped optical material 31 is accommodated in the mold set 20. The accommodated optical material 31 is positioned in the mold set 20 with the lower end fitted into the hollow portion 23b of the holding member 23 and with a slight gap between the upper mold 21 and the concave molding surface 21c. doing.

  As shown in FIG. 1, the mold set 20 is inserted into the molding chamber 14 from the insertion port 14 a and placed on the lower plate 12 a of the press stage 12 with the insertion-side shutter 15 retracted upward. The mold set 20 is loaded into the molding chamber 14, transferred into the molding chamber 14, and discharged from the molding chamber 14 by a transfer robot (not shown).

  The lower plate 12a and the upper plate 12c of the press stage 12 are heated to a predetermined temperature in advance by heaters 12f and 12g. When the mold set 20 is placed on the lower plate 12a, the cylinder 12d lowers the upper plate 12c and contacts the upper mold 21 of the mold set 20 as shown in FIG. 2A. Then, due to heat conduction from the lower plate 12a and the upper plate 12c, the optical material 31 is heated and softened to a pressable temperature equal to or higher than the yield point, for example (heating softening step).

  Next, the softened optical material 31 is pressed by pressing the lower mold 21 with the press shaft 12e (pressing process). Specifically, the press shaft drive unit 12k is configured to move the press shaft 12e from the initial state where the upper end is positioned in the through hole 12h of the lower plate 12a as shown in FIG. 2A and from the initial state where the upper end is lower plate 12a as shown in FIG. 2B. It is raised so as to protrude upward from the through hole 12h.

  As shown in FIG. 2C, the lower die 22 that is lifted by being pressed by the press shaft 12 e and the holding member 23 placed on the step portion 25 c of the sleeve 25 from the position where the base portion 22 a contacts the holding member 23. The holding member 23 ascends integrally with the outer diameter frame 24 located on the flange portion 23a. After the optical material 31 is pressed to a predetermined thickness by the lower mold 22, the temperature of the heaters 12f and 12g of the press stage 12 is lowered to cool the optical material 31 to, for example, the vicinity of the glass transition point.

  Although cooling of the optical material 31 is also performed in the cooling stage 13, the optical material 31 in the cooling process at the stage of cooling in the press stage 12 is released from the lower die 22 by sucking the lower die 22 ( Suction process).

  Specifically, as shown in FIG. 2D, first, the press shaft drive unit 12k lowers the press shaft 12e to an initial state where the upper end is located in the through hole 12h of the lower plate 12a. 1 includes a suction pipe 17, a suction path 12j and a through hole 12i of the base portion 12b, a through hole 12h of the lower plate 12a, a lower mold 22 and a sleeve 25 of the mold set 20, and a lower The lower die 22 is sucked downward through the space S defined by the plate 12a.

  The lower mold 22, the holding member 23, the outer diameter frame 24, and the optical material 31 are lowered by their own weight and the suction of the lower mold 22, and the optical material 31 is first released from the upper mold 21. As shown in FIG. 2E, when the flange portion 23a of the holding member 23 comes into contact with the step portion 25c of the sleeve 25, only the lower die 22 is lowered from there as shown in FIG. A tensile force is generated on the molding surface 22c, and the optical material 31 is released.

  A means for detecting when the lower die 22, the holding member 23, the outer diameter frame 24 and the optical material 31 are lowered by their own weight before suction and the optical element 31 is released from the upper die 21 and the lower die 22. By arranging it, the suction step can be omitted.

  After releasing the optical material 31 from the lower mold 22, the mold set 20 is transferred onto the lower plate 13 a of the cooling stage 13. The optical material 31 is further cooled to a predetermined temperature between the upper plate 13c and the lower plate 13a. When the die set 20 of the press stage 12 is transferred to the cooling stage 13, a new die set 20 is thrown into the press stage 12 through the slot 14a, and optical elements are sequentially manufactured.

  The mold set 20 in which the optical material 31 has been cooled in the cooling stage 13 is discharged out of the molding chamber 14 through the discharge port 14b with the discharge side shutter 16 retracted upward. Thereafter, the optical element manufactured from the mold set 20 is taken out.

  In the present embodiment described above, since the optical material 31 is released from the lower die 22 by sucking the lower die 22, a tensile force is applied to the lower die 22 before the optical material 31 is removed from the die set 20. Thus, the optical material 31 can be released from the lower mold 22. Therefore, it is possible to prevent the optical material 31 from contracting due to the lower mold 22 and causing stress in the optical material 31.

In addition, since the optical material 31 is released from the lower mold 22 by suction, it is possible to prevent the configuration for applying a tensile force to the lower mold 22 from hindering the transfer of the mold set 20.
Therefore, according to this Embodiment, it can prevent that the optical material 31 at the time of contraction produces a defect.

  In the present embodiment, the optical material 31 is released from the lower mold 22 by sucking the lower mold 22 through the space S defined by the lower mold 22, the sleeve 25, and the lower plate 12a. The optical material 31 can be reliably released from the lower mold 22 with a simple configuration.

  In the present embodiment, the lower mold 22 is sucked during the cooling process of the optical material 31. Therefore, when the optical material 31 is released from the lower mold 22 in a state where the shrinkage amount is small (for example, a temperature near the glass transition point), stress is generated in the optical material 31 and a defect occurs in the optical material 31 at the time of contraction. Can be effectively prevented.

  In the present embodiment, the lower mold 22 includes a convex molding surface 22c, and the upper mold 21 includes a concave molding surface 21c. Therefore, the optical material 31 is more easily inhibited from contracting by the lower mold 22 than the upper mold 21. However, by sucking the lower mold 22, the optical material 31 can be effectively prevented from cracking during contraction. The same applies to the case where the lower mold 22 includes the convex molding surface 22c and the upper mold 21 includes the flat molding surface.

  Further, when both the lower mold 22 and the upper mold 21 employ a configuration including a convex molding surface, and the curvature radius of the convex molding surface of the lower mold 22 is smaller than the curvature radius of the convex molding surface of the upper mold, an optical material Since the contraction of 31 is more likely to be inhibited by the lower mold 22 than the upper mold 21, the lower mold 22 can be sucked to effectively prevent the optical material 31 from cracking during contraction.

  However, the optical material 31 can be used regardless of the shape of the molding die, for example, when the lower die 22 includes a concave molding surface or a planar molding surface and the upper die 21 includes a convex molding surface. Since a stress is generated in no small amount, it is possible to obtain an effect that the optical element can be prevented from cracking by sucking the mold (lower mold 22 or upper mold 21).

Second Embodiment
FIG. 3 is a sectional view showing an optical element manufacturing apparatus 41 according to the second embodiment of the present invention.
4A and 4B are cross-sectional views showing the main part of the press stage 12 of the optical element manufacturing apparatus 41.

  The manufacturing apparatus 41 of the present embodiment mainly has a point that a flow path 12p as a blow mechanism is formed in a press shaft 12e '(press part), and the flow path 12p is formed of a cooling gas supply unit 51 and a cooling gas. Since it is different from the first embodiment in that it is connected to the supply pipe 52 and the other configurations are the same, detailed description thereof is omitted. In this embodiment, the flow path 12p is used as the blow mechanism, but an electromagnetic valve or the like may be further used as the blow mechanism.

  The press shaft 12e ′ has a cylindrical shape such as a cylindrical shape, for example, and a hollow portion of the cylinder is a flow path 12p. The flow path 12p is connected to the cooling gas supply pipe 52, for example, in the press shaft driving unit 12k ′. The cooling gas supply pipe 52 is connected to the cooling gas supply unit 51.

  The cooling gas supply unit 51 supplies a cooling gas such as nitrogen gas to the space S defined by the lower mold 22, the sleeve 25, and the lower plate 12a via the cooling gas supply pipe 52 and the flow path 12p. .

Hereinafter, the difference between the optical element manufacturing method using the manufacturing apparatus 41 and the first embodiment will be described.
The process is the same as in the first embodiment until the lower mold 21 is pressed by the press shaft 12e ′ and the softened optical material 31 is pressed.

  After the optical material 31 is pressed to a predetermined thickness, the temperature of the heaters 12f and 12g of the press stage 12 is lowered to cool the optical material 31 to, for example, the vicinity of the glass transition point. Thereafter, the press shaft 12e ′ is lowered to the initial state where the upper end is located in the through hole 12h of the lower plate 12a.

  Then, as shown in FIG. 4A, the cooling gas supply unit 51 gas passes through the cooling gas supply pipe 52 and the flow path 12p into the space S defined by the lower mold 22, the sleeve 25, and the lower plate 12a. Supply. Thereby, gas is blown with respect to the lower mold | type 22 (blow process), and the lower mold | type 22 is further cooled. When gas is blown into the lower mold 22, the gas that has flowed into the space S may be sucked by the vacuum pump 18 as in the suction step.

  In addition, when the lower mold | type 22, the holding member 23, the outer diameter frame 24, and the optical raw material 31 descend | fall by dead weight, and the space S is lose | eliminated, gas will flow from the flow path 12p of the press shaft 12e to the lower mold | type 22 without passing through the space S. However, it is possible to omit the blowing step by arranging a means for detecting the lowering of the lower die 22 due to its own weight.

  Next, the vacuum pump 18 shown in FIG. 1 includes a suction pipe 17, a suction path 12j and a through hole 12i of the base portion 12b, a through hole 12h of the lower plate 12a, a lower mold 22 and a sleeve 25 of the mold set 20, and The lower mold 22 is sucked downward through the space S defined by the lower plate 12a as shown in FIG. 4B. Thereafter, the release of the optical material 31, the cooling of the optical material 31 in the cooling stage 13, and the like are performed, but the description is omitted because it is the same as in the first embodiment.

  Also in the present embodiment described above, it is possible to prevent the optical material 31 from being damaged during contraction by, for example, releasing the optical material 31 from the lower die 22 by sucking the lower die 22. The same effects as those of the first embodiment can be obtained.

  In the present embodiment, the lower die 22 is cooled by blowing gas to the lower die 22. Therefore, the cooling of the optical material 31 can be promoted, and the manufacturing time of the optical element can be shortened.

  Moreover, in this Embodiment, gas is blown with respect to the lower mold | type 22 by supplying gas to the space S divided by the lower mold | type 22, the sleeve 25, and the lower plate 12a at a blow process. Therefore, the cooling of the optical material 31 can be surely promoted with a simple configuration.

  In the present embodiment, the press shaft 12 e ′ is formed with a flow path 12 p for blowing gas to the lower mold 22. Therefore, cooling of the optical material 31 can be promoted with a simple configuration.

  In the present embodiment, the lower mold 22 includes a convex molding surface 22c, and the upper mold 21 includes a concave molding surface 21c. Therefore, the optical material 31 is more easily inhibited from contracting by the lower mold 22 than the upper mold 21, and by cooling the lower mold 22, it is possible to effectively prevent cracks during contraction of the optical material 31. The same applies to the case where the lower mold 22 includes the convex molding surface 22c and the upper mold 21 includes the flat molding surface.

  Further, when both the lower mold 22 and the upper mold 21 are configured to include a convex molding surface, and the curvature radius of the convex molding surface of the lower mold 22 is smaller than the curvature radius of the convex molding surface of the upper mold 21, the optical Since the shrinkage of the material 31 is more likely to be inhibited by the lower die 22 than the upper die 21, the cracking of the optical material 31 during the shrinkage can be effectively prevented by cooling the lower die 22.

  In the present embodiment, the flow path 12p as the blow mechanism is formed in the press shaft 12e ′, but the flow path as the blow mechanism can be provided in the lower plate 12a and other members. In that case, it is possible to cool the lower mold 22 while the lower mold 22 is held by the press shaft, so that it is possible to prevent the lower mold 22 from falling by its own weight before the blowing process.

<Third Embodiment>
FIG. 5 is a sectional view showing an optical element manufacturing apparatus 61 according to the third embodiment of the present invention.
FIGS. 6A to 6C are cross-sectional views showing a main part of the cooling stage 63 of the optical element manufacturing apparatus 61.

The manufacturing apparatus 61 of the present embodiment is different from the first embodiment mainly in that the suction mechanism is disposed on the cooling stage 63, and the other configurations are the same, and thus detailed description thereof is omitted.
The upper plates 62c and 63c, cylinders 62d and 63d, heaters 62f, 62g, 63f, and 63g (heating unit) shown in FIG. 5 are the same as those in the first embodiment.

  The lower plate 62a and the base portion 62b of the press stage 62 are formed with through holes 62h and 62i that allow the press shaft 62e to slidably pass in the vertical direction. The press shaft 62e moves up and down by a press shaft driving unit 62k, which is a cylinder, for example. The protruding amount of the press shaft 62e from the lower plate 62a is measured by a scale (not shown), and a control unit (not shown) drives and controls the press shaft driving unit 62k based on the measured protruding amount.

  In the lower plate 63a of the cooling stage 63, a suction path (suction mechanism) 63h constituting a suction path of the suction pump 68 is formed so as to penetrate the center vertically. A suction path (suction mechanism) 63j communicating with the suction path 63h is formed in the base portion 63b of the cooling stage 63, and a suction pipe 67 is connected to the outside of the suction path 63j.

  The suction pump 68 includes a suction pipe 67, a suction path 63j of the base portion 63b, a suction path 63h of the lower plate 63a, a space S defined by the lower mold 22 and the sleeve 25, and the lower plate 12a of the mold set 20. The lower die 22 is sucked downward via

Hereinafter, the difference between the optical element manufacturing method using the manufacturing apparatus 61 and the above-described first embodiment will be described.
The process is the same as in the first embodiment until the lower mold 21 is pressed by the press shaft 62e and the softened optical material 31 is pressed.

  After the optical material 31 is pressed to a predetermined thickness, the temperature of the heaters 62f and 62g of the press stage 62 is lowered to cool the optical material 31 to, for example, the vicinity of the glass transition point. Then, the press shaft driving unit 62k lowers the press shaft 62e to the initial state where the upper end is located in the through hole 62h of the lower plate 62a.

  Thereafter, a transfer robot (not shown) transfers the mold set 20 onto the lower plate 63 a of the cooling stage 63. When the mold set 20 is placed on the lower plate 63a, the cylinder 63d lowers the upper plate 63c and contacts the upper mold 21 of the mold set 20 as shown in FIG. 6A.

Then, the optical material 31 in the cooling process at the stage of cooling in the press stage 62 is released from the lower mold 22 by the lower mold 22 being sucked downward (suction process).
Specifically, the vacuum pump 68 shown in FIG. 5 includes a suction pipe 67, a suction path 63j of the base portion 63b, a through hole 63h of the lower plate 63a, the lower mold 22 and the sleeve 25, and the lower plate of the mold set 20. The lower die 22 is sucked downward through the space S defined by 12a.

  The lower mold 22, the holding member 23, the outer diameter frame 24, and the optical material 31 are lowered by their own weight and the suction of the lower mold 22, and the optical material 31 is first released from the upper mold 21. 6B, when the flange portion 23a of the holding member 23 comes into contact with the step portion 25c of the sleeve 25, only the lower mold 22 descends from there, and a tensile force is applied to the convex molding surface 22c of the lower mold 22. Occurs and the optical material 31 is released.

  When the lower die 22, the holding member 23, the outer diameter frame 24, and the optical material 31 are lowered by their own weight and the optical element 31 is released from the upper die 21 and the lower die 22, a means for detecting it is arranged. By setting, the suction step can be omitted.

  After releasing the optical material 31 from the lower mold 22, the optical material 31 is discharged out of the molding chamber 14 from the discharge port 14 b in a state where the discharge side shutter 16 is retracted upward by a transfer robot (not shown). Thereafter, the optical element manufactured from the mold set 20 is taken out.

  Also in the present embodiment described above, it is possible to prevent the optical material 31 from being damaged during contraction by, for example, releasing the optical material 31 from the lower die 22 by sucking the lower die 22. The same effects as those of the first embodiment can be obtained.

  In the present embodiment, since the suction paths 63h and 63j as suction mechanisms are provided in the cooling stage 63, the cooling stage 63 is separated from the press stage 62 that presses the optical material 31 by the press shaft 62e. The mold 22 can be sucked, and the manufacturing tact can be shortened.

  In the press stage 62 or the cooling stage 63, a blow process for cooling the lower mold 22 may be performed by blowing gas to the lower mold 22 after the press process and before the suction process.

DESCRIPTION OF SYMBOLS 11 Optical element manufacturing apparatus 12 Press stage 13 Cooling stage 12a, 13a Lower plate 12b, 13b Base part 12c, 13c Upper plate 12d, 13d Cylinder 12e Press shaft 12f, 13f Heater 12g, 13g Heater 12h Through-hole 12i Through-hole 12j Suction Road 12k Press shaft drive part 12p Flow path 14 Molding chamber 14a Input port 14b Discharge port 15 Input side shutter 16 Discharge side shutter 17 Suction pipe 18 Suction pump 20 Mold set 21 Upper mold 21a Base 21b Flange part 21c Concave molding surface 22 Lower mold 22a base portion 22b convex portion 22c convex molding surface 23 holding member 23a flange portion 23b hollow portion 23c upper end surface 24 outer diameter frame 25 sleeve 25a thick portion 25b thin portion 25c step portion 31 optical material 41 optical element manufacturing apparatus 5 Cooling gas supply part 52 Cooling gas supply pipe 61 Optical element manufacturing apparatus 62 Press stage 63 Cooling stage 62a, 63a Lower plate 62b, 63b Base part 62c, 63c Upper plate 62d, 63d Cylinder 62e Press shaft 62f, 63f Heater 62g, 63g Heater 62h Through hole 63h Suction path 62i Through hole 63j Suction path 62k Press shaft drive part 67 Suction pipe 68 Suction pump S Space

Claims (9)

In the optical element manufacturing method of manufacturing the optical element while sequentially transferring the mold set containing the optical material,
A heat softening step of softening the optical material by heating;
A pressing step of pressing the optical material softened by pressing a mold included in the mold set;
A suction step of releasing the optical material from the molding mold by sucking the pressed said mold, only including,
The mold set includes a movable mold that is a mold that is movably disposed in the mold set and pressed in the pressing step, and a sleeve that is disposed on an outer periphery of the movable mold,
In the suction step, the optical material is sucked from the movable mold by sucking the movable mold through a space defined by the movable mold, the sleeve, and a mounting plate on which the mold set is mounted. A method for producing an optical element, which is released from the mold . In the method for manufacturing an optical element according to claim 1 Symbol placement,
The suction step is a method for manufacturing an optical element, which is performed in the course of cooling the optical material. In the manufacturing method of the optical element of Claim 1 or Claim 2 ,
A method for manufacturing an optical element, further comprising a blowing step that is performed after the pressing step and before the suction step and that cools the molding die by blowing gas to the pressed molding die. In the manufacturing method of the optical element of any one of Claims 1-3 ,
The mold set further includes a arranged fixed to face the mobile,
The movable mold includes a convex molding surface,
The method of manufacturing an optical element, wherein the fixed mold includes a concave molding surface or a flat molding surface. In the manufacturing method of the optical element of any one of Claims 1-3 ,
The mold set further includes a arranged fixed the mobile and opposite to,
The movable mold and the fixed mold include a convex molding surface,
The method of manufacturing an optical element, wherein a radius of curvature of the movable convex surface is smaller than a radius of curvature of the fixed convex surface. In an optical element manufacturing apparatus for manufacturing an optical element while sequentially transferring a mold set containing an optical material,
A heating section for softening the optical material by heating;
A pressing unit that presses the optical material softened by pressing a mold included in the mold set; and
A suction mechanism for releasing the optical material from the mold by sucking the pressed mold ; and
The mold set includes a movable mold that is a mold that is movably disposed in the mold set and pressed by the press unit, and a sleeve that is disposed on an outer periphery of the movable mold,
The suction mechanism sucks the movable die from the movable die by sucking the movable die through a space defined by the movable die, the sleeve, and a mounting plate on which the die set is placed. An optical element manufacturing apparatus for releasing the mold . In the optical element manufacturing apparatus according to claim 6 ,
The optical element manufacturing apparatus, further comprising a blow mechanism for blowing gas to the mold pressed by the press unit. In the optical element manufacturing apparatus according to claim 7 ,
In the press part, the flow path of the gas to be blown is formed,
The apparatus for manufacturing an optical element, wherein the blow mechanism is the flow path. In the optical element manufacturing apparatus according to any one of claims 6 to 8 ,
A press stage for pressing the optical material by the press unit;
A cooling stage for cooling the optical material,
The suction mechanism is an optical element manufacturing apparatus provided on the cooling stage.

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