JP5021205B2 - Mold press mold and optical element manufacturing method - Google Patents

Description

  The present invention relates to a mold press mold that does not require post-processing such as grinding and polishing of a molding surface by pressing a molding material such as glass with a precision-molded mold, and this mold press mold In particular, when molding optical elements such as biconcave lenses and plano-concave lenses, a mold press capable of satisfactorily supplying a molding material onto a lower mold molding surface having a convex surface or a flat surface. The present invention relates to a mold and an optical element manufacturing method.

  There is known a method of manufacturing an optical element such as a lens by press-molding a molding material such as glass by heating with a pair of upper and lower molding dies softened by heating and precisely processed into a predetermined shape (for example, Patent Document 1). 2).

  Patent Document 1 describes a molding method for positioning an optical material with respect to a molding die by moving a pair of positioning members in the molding die and bringing them into contact with each other with the optical material (molding material) interposed therebetween. ing. In particular, when molding a double-sided concave lens, the optical material must be placed on the lower mold of the convex shape, and if it is left displaced, it may fall off. Positioning is required.

  In Patent Document 2, the glass preform (molding material) is held at a position away from the mold by the holding means for holding the end surface of the glass preform (molding material), and then the glass preform is heated. A method of releasing the holding by the holding means and pressurizing the glass preform is described. Thus, a chemical reaction between the glass preform and the mold can be avoided during heating, and molding can be performed without impeding the radial flow of the glass preform during pressurization.

Japanese Patent No. 3501580 JP-A-9-286622

  When molding a molding material (such as a glass material) with a precision mold press and molding an optical element such as a lens, it is common to press and mold the molding material between a pair of upper and lower molds having opposing molding surfaces. Is. At this time, it is necessary to supply and arrange the molding material on the lower mold molding surface in advance, but depending on the shape of the optical element to be obtained, it is not always possible to arrange the molding material at the center position of the lower mold molding surface. Not easy.

As such an example, for example, when molding a plano-concave lens or biconcave lens, there is a case where a molding material is supplied and arranged on a lower mold molding surface having a flat surface or a convex surface, and in particular, the molding material has a convex curved surface. In the case where the surface facing the lower mold is not flat, positioning is difficult even if the lower mold forming surface is flat.
And in these cases, for example, if the molding material placed on the lower mold molding surface slides down during press molding or causes a positional shift, the molded optical element is unevenly thickened, resulting in a defective shape. In addition, the surface accuracy of the optical functional surface deteriorates due to uneven load application due to uneven thickness.

  According to the description of Patent Document 1, an optical material positioning member is arranged in a mold, and this is moved in opposite directions around a reference position by driving means such as a rack and a pinion, and the optical material is sandwiched between them. By abutting and stopping, the optical material is positioned with respect to the mold, and the positioning member is retracted by the driving means immediately before the molding surface abuts on the material during pressing.

  However, according to this method, since the positioning member is disposed inside the mold, the mold has an extremely complicated structure. For this reason, the heat capacity of the mold becomes large, and it is difficult to efficiently perform temperature control for temperature increase and decrease. Furthermore, if structures such as racks and pinions are placed in the vicinity of the mold, not only will the equipment increase in size, but it will also be necessary to consider the effects of thermal deformation of these structures, making the equipment design significantly more complex To do.

  Furthermore, when a mold consisting of upper and lower molds is fixed to the press device, and the temperature rise, press, and cooling are performed at the same position, the molding material should be positioned by a movable member that complicates the device as described above. Is possible to some extent, but in the molding method (details will be described later), the molding material is housed in a molding die separated from the press device, and appropriately transferred while being transferred inside the device. It is extremely inefficient and substantially impossible to provide such a large movable member in the mold.

  Further, Patent Document 2 discloses a drawing in which a disk-shaped preform is pressure-formed by an upper and lower mold having convex surfaces. That is, heating is performed in a state where the preform is placed on the upper end of the retaining ring, then the retaining ring is lowered by driving means, the preform is placed on the lower mold, and then the preform is pressurized by the upper and lower molds. ing. In this method, since the preform is always in contact with the inner periphery of the lower body mold, even if the molding surface of the lower mold is a convex shape, it is considered that the preform is hardly displaced.

However, in order to arrange the preforms in this way, the outer diameter between the individual preforms must always be kept constant so that the outer diameter of the preform is held in contact with the inner periphery of the lower body mold. I must. In addition, even if there is a difference in length between the outer diameters of the individual preforms, appropriate holding cannot be performed.
For this reason, it is necessary to perform preform preforming with precise control of the roundness of the horizontal cross section of the preform. In such preform preforming, polishing is usually performed to keep the dimensions within a predetermined range. Such processing will be necessary.

Incidentally, Patent Document 2 describes an example using a molding material processed into a disk shape, but does not particularly mention the molding method. In general, the molding material having such a shape can be obtained by processing (cold processing) such as cutting and polishing of a glass block. However, such processing has a disadvantage in that it requires many steps and is complicated. .
On the other hand, as a molding material for precision mold press, molten glass is preliminarily molded (hot molded) into a spherical or biconvex curved shape by dropping or flowing down on a receiving mold, or hot molded. After that, it is known to use a hot-worked additional shape. The molding material thus obtained is usually covered with a convex curved surface having no surface defects, which is very advantageous for forming an optical surface of a press-molded optical element, and the production efficiency is extremely high. high. Further, by controlling the flow rate at which the molten glass is dropped or flowed down, it is possible to maintain the volume accuracy and shape accuracy at a certain level or higher.

  However, it is not easy to supply and arrange a molding material having such a convex curved surface on a convex molding surface. It is difficult to keep the mold at the center on the molding surface, and often slips off from the molding surface or shifts in position. Furthermore, in general, the outer shape of the molding material by hot forming is not a perfect circle, and a difference between major and minor diameters may occur within a certain range. However, if such a molding material is directly applied to Patent Document 2, There is a great risk that it will be caught in the lower body mold and interfere with press molding.

  The present invention has been considered in view of the above circumstances, and can prevent the molding material supplied on the molding surface of the lower mold from slipping without providing a large movable member, and has a convex curved surface. It is an object of the present invention to provide a mold press mold and an optical element manufacturing method capable of stably supplying a molding material even when using.

In order to achieve the above object, a mold press mold of the present invention comprises a lower mold having a convex molding surface, and an upper mold having a molding surface on the opposite surface of the lower mold molding surface, A mold press molding apparatus for press-molding a molding material supplied on the lower mold between the upper mold and the lower mold, and an annular shape for supporting the molding material around the lower mold molding surface The support member is formed so as to protrude above the lower mold forming surface at a predetermined height , and the support member is at least the upper end edge on the inner peripheral surface side of the support member and the lower surface of the molding material. The peripheral portion is supported, and the molding material is supported so that the outer periphery of the molding material becomes an open space.

If comprised in this way, even if the lower mold forming surface has a convex surface , the support member provided around the lower mold forming surface is the lower peripheral part of the molding material supplied on the lower mold forming surface. Therefore, the sliding of the molding material can be suppressed without providing a large movable member, and the molding material can be arranged at a predetermined position and the state can be maintained.
In addition, since an open space is secured outside the periphery of the molding material supported by the supporting member, the molding material can be stably supported by the supporting member even if the dimensions of the molding material vary. Can be made.

Further, the mold press mold of the present invention includes a barrel mold in which the upper mold and the lower mold can be inserted from both ends, respectively, and the trunk mold is arranged in a horizontal direction between the upper mold and the lower mold. It can be set as the structure which controls a relative position.
If comprised in this way, since the horizontal relative position of an upper mold | type and a lower mold | type can be regulated with high precision by a trunk | drum type, the coaxial property of an up-and-down type | mold will be improved and an optical element with high eccentric accuracy will be obtained.

Moreover, the mold press mold of this invention can be set as the structure by which the said supporting member is provided so that attachment or detachment is possible.
If comprised in this way, when taking out the molding obtained by press molding from the lower mold forming surface, the support member is taken out of the molding die together with the molding, and when the temperature is lowered, the support member is removed from the molding. Thus, it is possible to easily separate the two without extending the molding cycle time.

In the mold press molding die of the present invention, the support member is formed in an annular shape, and is placed on a step formed around the lower mold molding surface and at a position lower than the lower mold molding surface. Can be configured. Further, the support member may have a vent hole in the middle of the lower mold surface and the step portion in the axial direction of the support member.
With this configuration, the atmospheric gas between the molding material supported by the support member and the lower mold molding surface can be smoothly discharged to the outside of the molding die through the vent holes during press molding. Further, it is possible to prevent a molding surface defect caused by the stay of the atmospheric gas.

Moreover, the mold press molding die of this invention can be set as the structure which has the taper-shaped inner periphery which the said support member reduces in diameter, so that an internal diameter goes below.
If comprised in this way, in the case of press molding, the press load concerning a molding material can be equalized, and the volume of the molding material to be used is excessively large relative to the volume of the optical element to be obtained. There is no need to do.

The optical element manufacturing method according to the present invention includes a molding die including a lower die on which a molding surface having a convex surface is formed, and an upper die on which a molding surface is formed on a surface opposite to the lower molding surface. In the method of manufacturing an optical element that uses and press-molds a molding material onto the lower mold, an annular support member that supports the molding material is formed around the lower mold molding surface. provided so as to protrude at a predetermined height above the surface, the lower surface peripheral portion of the forming material is supported by the upper edge of the inner peripheral surface side of at least the bearing member and being supported by said support member said The molding material is supplied so that an open space is secured outside the periphery of the molding material, and then the upper mold and the lower mold are relatively approached.

By adopting such a method, the molding material is stably supplied onto the lower mold molding surface while having a convex surface on the lower mold molding surface, and the sliding of the molding material is suppressed without providing a large movable member. can do. In addition, by securing an open space outside the peripheral edge of the molding material supported by the supporting member, it is possible to stably support the molding material even if there are variations in the dimensions of the molding material.

  Further, the optical element manufacturing method in the present invention can be a method in which the molding material has a convex curved surface, and a stable supply of the molding material can be achieved even if a molding material having a convex curved surface is used. It becomes possible.

In the method of manufacturing the optical element in the present invention, the lower surface peripheral portion of the molding material, but to be supported by the upper edge of the inner peripheral surface side of at least the bearing member, if such a method Even if the shape of the molding material varies, the molding material can be stably supported by the support member.

In the method of manufacturing an optical element according to the present invention, the upper mold and the lower mold can be inserted from both end sides, respectively, and the horizontal position of the upper mold and the lower mold is regulated and pressed. It can be set as the method of shaping | molding.
According to such a method, the relative position between the upper mold and the lower mold can be regulated with high accuracy, and an optical element with higher decentering accuracy can be obtained.

Moreover, the manufacturing method of the optical element in the present invention may be a method in which the molding material is supported on the support member so as not to be in contact with the lower mold molding surface, and then press molding is performed.
With such a method, the molding environment where the molding material is placed can be made equal to the upper and lower surfaces, and non-uniform pressing conditions can be avoided. Furthermore, the reaction at the contact interface between the molding material and the lower mold molding surface is avoided to prevent inconveniences such as fusing of the molding material to the molding surface and fogging and foaming on the molding surface of the press-molded molding. be able to.

In the method of manufacturing an optical element according to the present invention, the body mold and the support member are provided with ventilation holes, and the molding is supported by the support member when the upper mold and the lower mold are relatively close to each other. The atmospheric gas between the raw material and the lower mold forming surface can be discharged to the outside of the mold through the vent hole.
With such a method, when the upper mold and the lower mold are relatively close to each other, the atmosphere gas between the molding material supported by the support member and the lower mold molding surface is molded through the vent hole. Since it can be smoothly discharged to the outside of the mold, it is possible to prevent a molding surface defect caused by the retention of the atmospheric gas.

Moreover, the manufacturing method of the optical element in this invention can be set as the method in which the said shaping | molding raw material has a diameter larger than an optical element effective diameter.
With such a method, the molding material can be supported more stably by trying to obtain the molding material by making the portion outside the effective diameter of the optical element of the molding material a support position by the support member. The optical effective diameter of the optical element can be ensured.

Moreover, the manufacturing method of the optical element in this invention can be made into the method of performing the centering process which removes the outer peripheral part of the obtained molded object after press molding.
According to such a method, the press-molded molded body is subjected to centering, the transfer portion of the support member is deleted, and the center of the outer diameter of the optical element to be obtained is matched with the optical center. be able to.

The optical element manufacturing method according to the present invention may be a method of separating the molded body and the support member after the molded body obtained after press molding is taken out of the mold together with the support member. .
By adopting such a method, the support member is taken out from the mold together with the press-molded molded body, and the support member is removed from the molded body when the temperature is lowered. It does not extend the molding cycle time.

Moreover, the manufacturing method of the optical element in this invention can be set as the method of using what has a taper-shaped inner periphery which decreases in diameter as the said supporting member goes below.
With such a method, it is possible to equalize the press load applied to the molding material during pressing, and excessively increase the volume of the molding material to be used relative to the volume of the optical element to be obtained. There is no need.

  Further, in the method of manufacturing an optical element in the present invention, the molding material is a glass after the molten glass is dropped or dropped on the receiving mold and separated and preformed, or the glass after being dropped or dropped is separated. The lump may be preliminarily molded by further shape processing. Such a molding material is advantageous in both productivity and surface smoothness, and by applying to the present invention, a desired optical element can be produced stably.

In the optical element manufacturing method of the present invention, the mold is transferred to a plurality of processing chambers including a heating chamber, a press chamber, and a cooling chamber, and processing including heating, pressing, and cooling is performed in each processing chamber. By doing so, it can be set as the method by which the shaping | molding raw material accommodated in the inside of the said shaping | molding die is press-molded.
According to such a method, it is possible to efficiently raise and lower the temperature of the molding die while simultaneously using a large number of molding dies, and shorten the actual time (molding cycle time) required for individual molding. And since the molding die used in the method of the present invention is a compact that can be transported and prevents the molding material from sliding off without providing a large movable member, it is preferable to use such a manufacturing method. it can.

As described above, according to the present invention, the lower mold forming surface has a convex surface by supplying the molding material on the lower mold molding surface so that the lower surface side peripheral portion of the molding material is supported by the support member. However, the molding material can be reliably held in a predetermined position without causing the molding material to slide down or to be displaced. In addition, by providing an open space outside the peripheral edge of the molding material supported by the supporting member, it is possible to stably support the molding material even if there are variations in the dimensions of the molding material. .
Thereby, uneven thickness in press molding is prevented, and the surface accuracy of the obtained optical element is improved.

  Hereinafter, preferred embodiments of a mold press mold and an optical element manufacturing method according to the present invention will be described with reference to the drawings.

[Mold press mold]
First, an embodiment of a mold press mold (hereinafter simply referred to as a mold) according to the present invention will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view of a mold according to the present embodiment, showing a state when a press load is applied (see FIG. 4 (8)).
The molding die shown in FIG. 1 includes an upper die 10, a lower die 20, a body die 30 and a support member 40, and press-molds a molding material 50 between the upper die 10 and the lower die 20.

In this embodiment, the body die 30 regulates the relative position in the horizontal direction by sliding and guiding the upper and lower dies 10 and 20 when assembling the molding die or during press molding, thereby The coaxiality of 10, 20 is ensured.
That is, the body mold 30 is in direct contact with each of the upper and lower molds 10 and 20 and is slidably guided, and the clearance of the contact portion is controlled to a sufficiently small numerical value, so Coaxiality can be obtained.

For this reason, the sliding clearance between the body mold 30 and the upper and lower molds 10 and 20 is preferably 10 μm or less, particularly 5 μm or less in consideration of the required eccentric accuracy of the optical element. If the sliding clearance is controlled, the eccentricity between the molding surfaces 11 and 21 of the upper and lower molds 10 and 20 (shift: horizontal displacement of the molding surfaces 11 and 21 of the upper and lower molds 10 and 20, tilt: upper and lower molds 10 and 20. Can be suppressed with high accuracy.
In particular, in the present embodiment, the upper and lower dies 10 and 20 are positioned by the barrel die 30 surrounding the outer periphery of the molding surface 11 of the upper die 10 and also surrounding the outer periphery of the molding surface 21 of the lower die 20. Therefore, the mutual displacement (shift) between the upper and lower molds 10 and 20 can be suppressed. That is, the below-described support member 40 is arranged so that the trunk mold 30 can maintain the coaxiality of the upper and lower molds 10 and 20 high.

  In the present embodiment, the upper die 10 is slidably guided in the barrel die 30 with respect to the lower die 20 fitted in the barrel die 30 during press molding, and the upper and lower dies 10 and 20 are relatively moved. Although an example configured to approach and separate will be described, the configuration can be reversed. That is, the lower mold 20 may be slidably guided in the body mold 30 with respect to the upper mold 10 fitted in the body mold 30, and the upper and lower molds 10 and 20 ensure the coaxiality. However, the specific configuration is not limited as long as they are relatively close to and away from each other.

  The body mold 30 is provided with a vent hole 33 for preventing the movement of the upper and lower molds 10 and 20 from being hindered by the pressure difference between the inside and outside of the mold when the upper and lower molds 10 and 20 approach and separate. It is preferable to keep it. In particular, in the present embodiment, as shown in the drawing, a vent hole 33 is provided in a portion where the inner diameter of the body mold 30 is changed to be a stepped portion, and the molding die is increased and decreased in the volume in the gap of the stepped portion. It is preferable that the atmospheric gas is conducted through the vent hole 33 so that the inside is always equal to the external pressure. In addition, the support member 40 is preferably provided with a vent hole 41 for the same purpose as the trunk mold 30. This makes it possible to smoothly perform press molding and assembly / disassembly of the mold.

  The upper mold 10 has a molding surface 11 formed on the lower surface facing the lower mold 20. In the example shown in FIG. 1, the molding surface 11 is a convex surface, but may be a concave surface or a flat surface. Further, a flange portion 12 having a diameter larger than that of the molding surface 11 is formed at the upper portion of the upper mold 10, and this flange portion 12 is accommodated in a large-diameter inner peripheral portion 31 formed at the upper portion of the body mold 30. The

  At this time, when the upper surface of the upper mold 10 and the upper surface of the trunk mold 30 are flush with each other, the lower surface of the flange portion 12 formed on the upper mold 10 and the small-diameter inner peripheral section formed on the trunk mold 30 It is preferable that a gap G having a predetermined dimension or more is secured between the upper end of 32. By securing such a gap G, the upper die 10 is pushed in until the upper surface of the upper die 10 coincides with the upper surface of the barrel die 30 during press molding, and the thickness of the molded body 15 is once determined. However, it is possible to continue to apply the necessary load (only the weight of the upper mold 10 may be applied) to the molded body 51 and to allow the upper mold 10 to descend following the thermal contraction of the molded body 51 (FIG. 4 (8) and FIG. 5 (9)).

In the example shown in FIG. 1, a molding surface 21 having a convex surface is formed on the upper surface facing the upper mold 10 of the lower mold 20 . Further, a flange portion 22 having a diameter larger than that of the molding surface 21 is formed at the lower portion of the lower mold 20. At the time of press molding, the lower surface of the barrel die 30 is brought into contact with the upper surface of the flange portion 22 and is brought into close contact with each other by the press pressure, whereby the mutual position of the lower die 20 and the barrel die 30 is defined with high accuracy. This also suppresses the tilt.

Further, a step portion 23 is formed on the outer periphery of the molding surface 21 of the lower mold 20 at a position lower than the molding surface 21 and higher than the flange portion 22, and surrounds the molding surface 21 around the step portion 23. Further, an annular support member 40 is disposed.
It is preferable that the outer diameter of the support member 40 held by the step portion 23 is equal to or smaller than the outer periphery of the lower mold 20 (the sliding portion with the body mold 30). Thereby, the support member 40 does not obstruct the sliding guide of the lower mold 20 by the trunk mold 30 and does not deteriorate the coaxiality of the upper and lower molds 10 and 20.

The support member 40 supports the molding material 50 supplied on the lower mold 20 to prevent the molding material 50 from slipping or shifting, but supports the peripheral portion on the lower surface side of the molding material 50. The specific configuration is not particularly limited as long as an open space can be secured outside the peripheral edge of the molding material 50 supported by the support member 40. By securing an open space outside the peripheral edge of the molding material 50 supported by the supporting member 40, the maximum outer diameter of the molding material 50 varies due to individual differences in the molding material 50 supplied onto the lower mold 20. In some cases, even when the horizontal cross section of the molding material 50 is not a perfect circle and there is a difference in length depending on the part of the molding material 50, the molding material 50 is stably supported and the state is maintained. be able to.
At this time, the open space secured outside the peripheral edge of the molding material 50 supported by the supporting member 40 may be a space that can allow individual differences in the molding material 50, and the upper and lower molds 10 and 20 are assembled. Later, a space accommodated in the trunk mold 30 may be used.

Here, the support means that the molding material 50 can maintain a certain posture. Further, the position at which the molding material 50 is supported by the supporting member 40 (peripheral portion on the lower surface side) can stably support the molding material 50, and the optical effective diameter of an optical element such as a lens to be obtained, Preferably, the centering diameter (the process of cutting the outer periphery of the press-formed molded body 51 in order to make the outer diameter center coincide with the optical center, that is, the final optical element after the centering process is performed. It is preferable to satisfy the following relational expression (1), and the following relational expression (1) is satisfied.
[Optical effective diameter] ≦ [Optical element effective diameter (= centering diameter)] <[Inner diameter of support member (support position)] <[Diameter of molding material] (1)

  More specifically, preferably, the molding material 50 is supported when the molding material 50 having a maximum outer diameter larger than the effective diameter of the optical element is used and the molding material 50 has a maximum outer diameter (diameter) of 2r. The position is preferably in the range of 0.5 to 0.95r from the center of the molding material 50, and more preferably in the range of 0.7 to 0.95r. Thereby, the removal rate at the time of performing the centering process on the molded body 51 is reduced, and efficient production becomes possible.

The support member 40 may be formed integrally with the lower mold 20, but may be formed separately from the lower mold 20. When the support member 40 is formed separately from the lower mold 20, it can be fixed to the lower mold 20 using a pin or the like. However, as in the example shown in FIG. It is preferable that it is detachably provided. In order to detachably mount the support member 40 formed separately on the outer periphery of the molding surface 21 of the lower mold 20, for example, as shown in the drawing, around the molding surface 21 of the lower mold 20, the molding surface The step portion 23 may be formed at a position lower than 21 and higher than the flange portion 22, and the support member 40 may be placed on the step portion 23.
At this time, the vent hole 41 provided in the support member 40 described above is provided at a position where the molding material 50 does not enter the vent hole 41 during press molding. Specifically, the support member 40 is placed on the step portion 23. In this state, it is preferable that the support member 40 is provided at a position between the peripheral portion of the molding surface 21 of the lower mold 20 and the step portion 23 in the axial direction.

  In the illustrated example, the vent hole 41 is provided so as to penetrate the support member 40 in a substantially radial direction, and the clearance between the inner peripheral surface of the support member 40 and the lower mold 20, the outer peripheral surface of the support member 40 and the trunk shape. 30 and the air hole 33. Thereby, when the atmospheric gas existing in the space between the molding material 50 and the lower mold molding surface 21 is compressed by the proximity of the upper and lower molds 10 and 20 (press molding), the atmospheric gas in the molding mold is supported. The clearance between the inner peripheral surface of the member 40 and the lower mold 20, the vent hole 41 of the support member 40, the clearance between the outer peripheral surface of the support member 40 and the trunk mold 30, and the vent hole 33 of the trunk mold 30. Can be released to the outside.

Therefore, by providing such a vent hole 41, it is possible to balance the inside of the mold and the external pressure by releasing the atmospheric gas to the outside of the mold.
As will be described later, the clearance between the outer peripheral surface of the support member 40 and the trunk mold 30 does not directly affect the eccentricity accuracy of the optical element to be molded, and therefore the ventilation hole 41 of the support member 40 and the ventilation hole 33 of the trunk mold 30 are formed. The communication can be set to such an extent that the atmospheric gas is discharged without hindrance.

  By making the support member 40 detachable from the lower mold 20, the support member 40 is taken out of the mold together with the molded body 51 when the press-molded molded body 51 is taken out from the molding surface 21 of the lower mold 20. be able to. For this reason, after the press molding, if the molded body 51 and the support member 40 are taken out from the mold while being in close contact with each other, and then the support member 40 is removed from the molded body 51 when the temperature is further lowered, Both can be easily separated.

Moreover, it is preferable that the inner periphery of the support member 40 is tapered, and has an inclined surface such that the inner diameter becomes smaller toward the lower side (closer to the molding surface 21 of the lower mold 20). Thereby, at the time of press molding, it is possible to avoid the occurrence of poor filling or pressurization in the portion along the outer periphery of the molding surface 21, and the outer diameter of the molding material 50 is increased more than necessary in order to ensure an effective optical element diameter. In order to prevent the usage amount (volume) of the molding material 50 from increasing excessively, it is effective to form such an inclination on the inner periphery of the support member 40.
The clearance between the support member 40 and the body mold 30 is not directly related to the eccentricity accuracy of the optical element, and may be about 5 to 50 μm. The clearance between the center of the outer diameter of the optical element to be obtained and its optical axis. Consistency can be obtained by centering the press-molded molded body 51.

The shape and dimensions of the support member 40 are such that at least the upper end edge on the inner peripheral surface side of the support member 40 is sufficient to support the lower surface side peripheral portion of the glass material supplied onto the lower mold 20. If the upper end side of 40 protrudes upwards rather than the molding surface 21 of the lower mold | type 20, it will not restrict | limit in particular (refer FIG. 3 (4)).
At this time, the molding material 50 may be in a state of being in contact with the molding surface 21 of the lower mold 20 or in a state of being supported only by the support member 40 without being in contact with the molding surface 21 of the lower mold 20. However, in particular, when press molding is performed using the molding die according to the present embodiment in a molding apparatus as will be described later, the molding die containing the molding material 50 is heated together with the molding material 50. If the molding material 50 and the molding die (the molding surface 21 of the lower mold 20) are in contact with each other, a reaction occurs between the two at the interface, and the molding material 21 becomes a molding surface 21. There is a case where it becomes a cause of fogging and foaming on the molding surface of the molded body 51 and foaming. Further, it is preferable that the molding conditions are not different between the upper and lower surfaces of the molding material 50.
For this reason, it is preferable that the upper end side of the support member 40 protrudes above the molding surface 21 of the lower mold 20 to such an extent that the molding material 50 can be supported so as not to contact the molding surface 21 of the lower mold 20.
This is particularly effective when the lower mold 20 is more easily heated by the heat capacity of the holding table 75 in a molding apparatus as will be described later.

  The portion of the support member 40 that supports the molding material 50 (upper end edge on the inner peripheral side) may have a square shape, or may have an R chamfer or a C chamfer. It may be a curved surface shape along the curved surface of the molding material 50.

Here, when to support the forming material 50 to support member 40, by supporting the molding material 50 at the upper edge of the inner peripheral surface of at least the bearing member 40, can accommodate variations in the shape of the molding material 50, the molding material Even if there is variation in the shape of the molding material 50, the lower surface side peripheral portion of the molding material 50 is supported by at least the upper edge on the inner peripheral surface side of the supporting member 40. It can be supported stably.
Further, when the molding material 50 is supported, the support member 40 is not particularly required to be in contact with the molding material 50 over the entire circumference of the molding material 50, and is formed with the molding material 50 having a predetermined interval in the circumferential direction. The support member 40 may support the molding material 50 by partial contact.

  By the way, when the height of the support member 40 is too large, the portion protruding on the molding surface 21 of the lower mold 20 is too high, and is used for sliding and guiding the upper mold 10 during press molding. The height (sliding guide length) of the small-diameter inner peripheral portion 32 of the body mold 30 becomes relatively small, and there arises a disadvantage that it becomes difficult to obtain the eccentricity (particularly tilt) accuracy of the molded body. This is because the tilt angle of the upper mold 10 allowed in the body mold 30 is determined by the sliding clearance between the body mold 30 and the upper mold 10 and the sliding guide length, so that the sliding clearance is constant. For example, as the sliding guide length is increased, the upper mold 10 is prevented from being tilted, the coaxiality of the upper and lower molds 10 and 20 is improved, and the eccentricity accuracy of the molded body as the optical element can be increased. On the other hand, when the sliding guide length is reduced, the effect of suppressing the upper mold 10 from falling is impaired. Specific dimensions of the support member 40 are determined in consideration of such points.

  Therefore, more preferably, the height of the portion protruding on the molding surface 21 of the lower mold 20 of the support member 40 is determined in consideration of the sliding guide length in the trunk mold 30 and the shape of the molded body 51 to be obtained. From the relationship with dimensions, etc., it is set to be as low as possible without causing any hindrance to molding. For example, when the thickness of the outer peripheral portion of the molded body 51 to be obtained is h, the height of the portion protruding on the molding surface 21 of the lower mold 20 is more than 0.9 h and less than 1.2 h. Is preferred.

Here, the height of the support member 40 is not excessively large when the molding material 50 is supplied onto the lower mold 20 on which the support member 40 is arranged and when the molded body 51 is taken out after molding. This is also advantageous in that no interference occurs with a robot that sucks and conveys the material 50 and the molded body 51.

In the present invention, the material of the upper mold 10, the lower mold 20, the trunk mold 30, and the support member 40 is not particularly limited. List cermets of silicon carbide, silicon, silicon nitride, tungsten carbide, aluminum oxide and titanium carbide, or those coated with diamond, refractory metal, noble metal alloy, carbide, nitride, boride, oxide, etc. Can do.
A single component layer or a mixture of amorphous and / or crystalline graphite and / or diamond is formed on the molding surfaces 11 and 21 of the upper and lower molds 10 and 20 and the support member 40 in order to prevent glass fusion. It is preferable to use a carbon film composed of layers or a release film made of a noble metal alloy.

Moreover, there is no restriction | limiting in particular in the material of the shaping | molding raw material 50 used for this invention. For example, a glass material such as a glass preform can be used.
The shape of the molding material 50 is preformed into a spherical shape, a biconvex curved surface shape, or a shape having a flat surface and a convex surface by, for example, dropping glass from the molten state onto the receiving mold or flowing it down. The glass lump after being molded) or separated while dropping or flowing down can be further processed in a hot manner. Such a molding material is advantageous in both productivity and surface smoothness, and by applying to the present invention, a desired optical element can be produced stably. In the present invention, a molding material having a convex surface is preferably used, and a biconvex curved shape is particularly preferable.

  Next, a mold press molding apparatus (hereinafter simply referred to as a molding apparatus) suitable for performing press molding using the molding die according to the present invention will be described with reference to FIG. FIG. 2 is a schematic plan view of a rotary transfer molding apparatus shown as an example of such a molding apparatus.

The molding apparatus shown in FIG. 2 includes an extraction / insertion chamber P1 and a large number of processing chambers P2 to P8 arranged side by side in the circumferential direction.
In the take-out / insertion chamber P1, an operation of taking out the molding die that has been molded and an operation of inserting a molding die that contains a molding material to be newly used for molding are performed. The molding die inserted from the take-out / insertion chamber P1 is always held in a state in which a molding material (or molded body) is accommodated, for example, by being held on a holding table attached to a rotary table that rotates in the direction of the arrow in the figure. It sequentially passes through the processing chambers P2 to P8 under a non-oxidizing gas atmosphere (inert gas atmosphere). The rotary table rotates intermittently at regular intervals, and the mold moves between adjacent processing chambers by this intermittent rotation. And this fixed time becomes a molding cycle time.

  Here, P2 is a first heating chamber, P3 is a second heating chamber, and P4 is a third heating chamber (or soaking chamber), which are also collectively referred to as a heating unit. P5 is a press chamber, and a press load is applied to a mold set at a temperature suitable for press molding in the heating section. P6 is a first slow cooling chamber, P7 is a second slow cooling chamber, and P8 is a rapid cooling chamber. These are also collectively referred to as a cooling section, and the mold is cooled after a press load is applied. These processing chambers P2 to P8 are arranged at substantially equal intervals, and are controlled to a temperature suitable for each processing, and in order to keep the temperature in each processing chamber at a predetermined temperature, shutters S1 to S6 are used. It is partitioned.

If a molding apparatus as shown in FIG. 2 is used, a desired optical element can be efficiently obtained by subjecting a mold containing a molding material (or molded body) to appropriate processing while sequentially transporting each processing chamber. Can be manufactured.
That is, since the temperature of the mold is increased to a temperature suitable for press molding, press load is applied, and the subsequent cooling process is performed by the mold passing through each processing chamber arranged two-dimensionally. These molding dies can be used at the same time, and the actual time (molding cycle time) required for each molding is shortened.
As described above, the time required for the rotary table to rotate intermittently and the mold to move between adjacent processing chambers is the molding cycle time.

  The molding die according to the present invention is suitable for heating, pressing, and cooling by transferring the molding die containing the molding material (or molded body) to each processing chamber such as a heating chamber, a press chamber, and a cooling chamber. Although it is preferably used in a molding apparatus that sequentially performs processing, the specific configuration of such a molding apparatus is not limited to the above-described example. For example, in the above-described example, the mold is transferred by the rotary table, but it is configured so that it can pass through each processing chamber arranged two-dimensionally (in some cases three-dimensionally) at a predetermined time interval. If it is what is carried out, the means in particular to transfer a shaping | molding die will not be restrict | limited.

  Moreover, the arrangement configuration of each processing chamber can be appropriately changed in order to optimize the heating process and the cooling process in accordance with the composition of the molding material and the shape of the molded body to be obtained. For example, it is possible to make changes such as four heating chambers or three cooling chambers. In order to further improve production efficiency, the same number of heating chambers, press chambers, and cooling chambers are provided in series, and multiple types of press molding that require different temperature conditions and different pressurization conditions are performed simultaneously. May be.

  Further, in order to improve production efficiency, for example, a plurality of molds are provided in each processing chamber by, for example, allowing a plurality of holders used in the same process to pass through each processing chamber at the same time. They can be processed simultaneously. Specifically, when processing such as heating, application of a press load, and cooling processing is performed in each processing chamber, two or more molds are arranged in the traveling direction, and the same processing is simultaneously performed on them. Can do. In this case, the press chamber is preferably provided with two or more pressing means arranged in the traveling direction.

[Method for Manufacturing Optical Element]
Next, referring to FIG. 3 to FIG. 6, based on an example in which the molding die shown in FIG. 1 is applied to the molding apparatus shown in FIG. explain. 3 is an explanatory view showing steps (1) to (4) in the method of manufacturing an optical element according to the present embodiment, FIG. 4 is an explanatory view showing the steps (5) to (8), and FIG. FIG. 6 is an explanatory view showing the steps (9) to (12), and FIG. 6 is an explanatory view showing the steps (13) to (14).

Steps (1) to (4): Molding material supply step Conveying arm with suction pad 61 for the molding die waiting in a state where the lower die 20 and the upper die 10 are separated (see FIG. 3 (1)). By 60, the shaping | molding raw material (for example, glass preform) 50 preformed in the shape which has a convex curve (in the example shown in figure, a biconvex curve shape) is supplied (refer FIG. 3 (2)). When the suction pad 61 reaches the molding surface 21 of the lower mold 20 with accuracy within a predetermined range (see FIG. 3 (3)), the molding material 50 becomes a peripheral portion on the lower surface side by releasing the suction. Is supported on the upper end edge on the inner peripheral side of the support member 40 and held on the support member 40 without sliding down (see FIG. 3 (4)).

At this time, as shown in FIG. 3 (4), the molding material 50 supported by the supporting member 40 does not come into contact with other parts of the molding die, and an open space is secured outside the peripheral edge thereof. Yes. Furthermore, the molding material 50 is supported by the support member 40 in a non-contact state with the molding surface 21 of the lower mold 20, and this state is maintained until a press process described later.
Further, the molding material 50 has a diameter larger than the outer diameter (optical element effective diameter) of the optical element to be obtained, and is located on the outer side of the optical element effective diameter of the molding material 50 (lower surface side periphery). Part) is supported by the obstacle member 40, so that the molding material 50 can be supported more stably and the outer diameter of the optical element to be obtained can be secured.

  When the molding material 50 is supplied, the center of the suction pad 61 and the center of the molding material 50 are aligned in advance, and the center of the suction pad 61 and the center of the molding surface 21 of the lower mold 20 are provided. It is preferable to control the operation of the transfer arm 60 so that the molding material 50 is placed on the holding member 40 in a state in which they substantially match. To do. Further, the position of the body mold 30 in which the upper mold 10 is incorporated is fixed by the holding means 80.

Step (5): Assembling Step of Molding Mold When the molding material 50 is held on the support member 40, the mounting table 70 is raised and the lower mold 20 is assembled into the body mold 30 (see FIG. 4 (5)). . At this time, the clearance between the body mold 30 and the lower mold 20 is preferably 5 μm or less. Further, it is preferable that the upper mold 10 and the trunk mold 30 assembled in advance have the same clearance. Thereby, the eccentricity between the molding surfaces 11 and 21 of the upper and lower molds 10 and 20 can be suppressed with high accuracy.
When the lower mold 20 is assembled in the body mold 30 and the upper surface of the flange portion 22 of the lower mold 20 abuts on the lower surface of the body mold 30, as shown in FIG. The upper surface of the mold 10 is pushed up to a position higher than the upper surface of the body mold 30.
When assembling the mold, the upper mold 10 and the trunk mold 30 may be lowered by the holding means 80 instead of raising the mounting table 70.

In the above steps (1) to (5), the mounting table is obtained by sucking the atmospheric gas from the opening 71 provided in the mounting table 70 so that the lower mold 20 does not shift on the mounting table 70. The lower mold 20 can be adhered and fixed on the 70. Further, as will be described later, when the mold is disassembled, the lower mold 20 is brought into close contact with the mounting table 70 by suction of the atmospheric gas, and the position when the lower mold 20 is extracted from the body mold 30 is maintained. Thus, it is possible to avoid the horizontal relative position of the lower mold 20 and the trunk mold 30 from shifting.
In addition, according to said process (1)-(5), the shaping | molding die accommodated and assembled with the shaping | molding raw material 50 is inserted in a shaping | molding apparatus from the taking-out / insertion chamber P1 in the shaping | molding apparatus shown in FIG. However, the above steps (1) to (5) may be performed in the take-out / insertion chamber P1.

Step (6): Heating step The molding material 50 is accommodated and the molding die inserted in the molding apparatus is sequentially transferred to the heating chambers P2 to P4 by holding it on a holding stand 75 attached to a rotary table. While heating (see FIG. 4 (6)). Thus, the temperature of the molding material 50 together with the molding die is raised to a temperature suitable for press molding.
At this time, for example, the first heating chamber P <b> 2 maintains a high temperature equal to or higher than the pressing temperature of the molding material 50 and rapidly heats the molding die and the molding material 50. And the shaping | molding die in which the shaping | molding raw material 50 was accommodated is stopped for a predetermined time in the 1st heating chamber P2, and is transferred to the 2nd heating chamber P3 according to rotation of a turntable. Due to the heating in the second heating chamber P3, the mold and the molding material 50 are further heated and soaked to approach the press temperature. Next, the molding die and the molding material 50 are soaked in the third heating chamber P4 so that the viscosity of the molding material 50 is 10 ⁶ to 10 ⁹ poise suitable for press molding. Preferably, the temperature of the molding material 50 is The temperature is set to a viscosity of 10 ⁶ to 10 ⁸ poise.
In addition, there is no restriction | limiting in particular in the heating means with which the heating chambers P2-P4 are equipped. For example, a heater by resistance heating, a high frequency induction coil, or the like can be used.

Steps (7) to (8): Pressing Step The mold that has reached an appropriate temperature is transferred to the press chamber P5 (see FIG. 4 (7)). In the press chamber P5, a press load is applied to the mold by a press head 90 from above the mold at a predetermined pressure (for example, 30 to 200 Kg / cm ² ) and for a predetermined time (for example, several tens of seconds) (see FIG. 4 (8)). At this time, the atmospheric gas interposed between the lower mold 20 and the glass material 50 is discharged to the outside of the mold through the vent hole 41 of the support member 40 and the vent hole 33 of the trunk mold 30.
When the lower surface of the press head 90 comes into contact with the upper surface of the body mold 30, the thickness of the molded body 51 is defined, and then the press head 90 is lifted to cancel the application of the press load, thereby completing the pressing process. To do.

Step (9): Cooling Step After the pressing step, the mold is sequentially transferred to the slow cooling chambers P6 and P7 and the quenching chamber P8 and subjected to a cooling process (see FIG. 5 (9)).
In the quenching chamber P8, quenching with a cooling gas can be performed, and the molded body 51 is cooled until the temperature becomes a glass transition point or lower. At this time, in the molding die, the gap G as described above is secured with a predetermined dimension between the lower surface of the flange portion 12 of the upper die 10 and the upper end of the small-diameter inner peripheral portion 32 of the body die 30. Thus, it becomes possible for the upper mold 10 to follow the shrinkage of the glass by its own weight, and good shape accuracy can be obtained.
In addition, when the upper mold | type 10 descend | falls following the shrinkage | contraction of glass, the space | interval of the clearance gap G between the flange part 12 of the upper mold | type 10 and the upper end surface of the small diameter inner peripheral part 32 of the trunk | drum 30 will become narrow.

Steps (10) to (11): Mold Disassembly Step When the mold returns to the take-out / insertion chamber P1, the mold is taken out of the molding apparatus, disassembled the mold, and removed the molded body 51. Further, a new molding material 50 is supplied.
In the step of disassembling the mold, the mold containing the molded body 51 is transferred to the mounting table 70 by the robot (see FIG. 5 (10)) and positioned by chucking the periphery. Then, atmospheric gas is sucked from the opening 71 of the mounting table 70, the lower mold 20 is integrally held on the mounting table 70, the mounting table 70 is lowered vertically, and the lower mold 20 is moved from the trunk mold 30. And the upper mold 10 and the lower mold 20 are separated (see FIG. 5 (11)). When the lower mold 20 is extracted from the body mold 30, the lower mold 20 is integrally held on the mounting table 70, and the position when the lower mold 20 is extracted from the body mold 30 is maintained. It is possible to avoid the horizontal relative position of the trunk mold 30 from shifting.
At this time, the position of the barrel die 30 in which the upper die 10 is incorporated is fixed by the holding means 80, as in the molding material supply step and the molding die assembly step described above.
In the take-out / insertion chamber P1 that is not in an inert gas atmosphere, it is preferable to control the temperature of the mold so that the temperature of the mold becomes 250 ° C. or less in consideration of prevention of oxidation of the mold.

Steps (12) to (14): Step of taking out optical elements After the lower die 20 is extracted from the body die 30, the transfer arm 60 is inserted between the upper and lower dies 10 and 20 (see FIG. 5 (12)). Then, the molded body 51 is sucked and sucked by the suction pad 61 at the tip (see FIG. 6 (13)), and the molded body 51 is taken out from the molding surface 21 of the lower mold 20 (see FIG. 6 (14)).

At this time, since the support member 40 is detachably provided to the lower mold 20, it can be taken out together with the molded body 51. After the molded body 51 and the support member 40 are taken out from the mold while being in close contact with each other, the support member 40 is removed from the molded body 51 when the temperature is further lowered, so that the both can be easily separated. be able to. Then, the separated molded body 51 is centered as necessary, and the center of the outer diameter of the optical element and the optical center thereof are made to coincide with each other, whereby a desired optical element can be obtained.
In addition, when taking out the support member 40 from a shaping | molding die with the molded object 51, the several support member 40 is prepared and prior to a molding raw material supply process (above-mentioned process (1)-(4)). Thus, the support member 40 is supplied onto the lower mold 20.

  After these steps (1) to (14) are completed, the support member 40 is supplied onto the lower mold 20 as necessary, and then the process returns to the step (1), and the above cycle is repeated, thereby press forming. Can be performed continuously.

  In the optical element manufacturing method according to the present embodiment as described above, the molding material is supplied onto the lower molding surface so that the lower surface side peripheral portion of the molding material is supported by the supporting member. Even if it has a convex surface or a flat surface, the molding material can be reliably held in a predetermined position without causing the molding material to slide down or to be displaced. In addition, by securing an open space outside the periphery of the molding material supported by the supporting member, it is possible to support the molding material stably even if the dimensions of the molding material vary. Thereby, uneven thickness in press molding is prevented, and the surface accuracy of the obtained optical element is improved.

  Further, when the molding material 50 is in contact with the molding surface 21 of the lower mold 20, when using the transfer molding device as described above, the contact time tends to be long. Although reaction is likely to occur between the two at the contact interface with the molding surface 21, in this embodiment, the molding material 50 is transferred to the pressing process in a non-contact state with the molding surface 21 of the lower mold 20. The problem can be effectively avoided. In particular, reactivity such as phosphate glass materials, glass materials containing a large amount of high refractive index components (for example, nd ≧ 1.7) such as W, Ti, Nb, or glass materials containing a large amount of alkali metals. It is extremely effective when press-molding using high glass material.

  In addition, the mold is transferred to a plurality of processing chambers including a heating chamber, a press chamber, and a cooling chamber, and the processing including heating, pressing, and cooling is performed in each processing chamber, so that the mold is accommodated inside the molding die. Since the molded material 50 is press-molded, while using a large number of molds at the same time, the temperature of the molds can be raised and lowered efficiently, and the actual time (molding cycle time) required for each molding can be shortened. Can do. And since the shaping | molding die in this embodiment regulates sliding of the shaping | molding raw material 50, without providing a large-scale movable member, such a manufacturing method can be used suitably.

  While the present invention has been described with reference to the preferred embodiment, it is needless to say that the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. .

  For example, the suction member 24 is provided to communicate with the bottom surface of the lower mold 20 and the step portion 23 on which the support member 40 is disposed, and atmospheric gas is sucked through the suction hole 24 so that the support member 40 is lowered. It can also be made to adhere to 20. When the support member 40 and the lower mold 20 are brought into close contact with each other by such atmospheric gas suction, when the mold is disassembled and the upper and lower molds 10 and 20 are separated from each other with a simple configuration in which the suction air holes 24 are provided. In addition, the molded body 51 and the support member 40 can be prevented from adhering to the upper mold 10 side, and when the molded body 51 is taken out, only the molded body 51 is separated from the lower mold 20 and the support member 40 and taken out. Is possible.

Specifically, as shown in FIG. 7, the lower mold 20 is provided with a suction vent 24 that communicates the bottom surface of the lower mold 20 and the stepped portion 23. Then, in the step of disassembling the mold, atmospheric gas is sucked from the opening 71 of the mounting table 70, and the mounting table 70 is lowered vertically while simultaneously sucking the lower mold 20 and the support member 40. Thereby, the lower mold | type 20, the support member 40, and the molded object 51 can be extracted from the trunk | drum 30 in the state hold | maintained integrally on the mounting base 70. FIG. By doing so, it is possible to prevent the molded body 51 from sticking to the molding surface 11 of the upper mold 10 when the mold is disassembled.
Here, FIG. 7A and FIG. 7B are explanatory views corresponding to FIG. 5 (10) and FIG. 11 (11) showing the disassembly process of the mold.

Further, as shown in FIG. 8, when the molded body 51 is taken out from the lower mold 20 in the step of taking out the optical element, the lower mold 20 and the support member 40 are sucked using the suction air holes 24 to thereby support the support member 40. And the lower mold 20 can be brought into close contact with each other. Accordingly, only the molded body 51 may be taken out from the molding surface 21 of the lower mold 20 by the suction pad 61.
Here, FIGS. 8A and 8B are explanatory views corresponding to FIGS. 6 (13) and (14), respectively, showing the optical element taking-out process.

  In carrying out the present invention in such a manner, the exhaust means for suction causes the lower mold 20 to adhere and be fixed on the mounting table 70 on which the molding die is placed when the molding die is assembled / disassembled. Therefore, existing facilities can be used as they are.

  The present invention relates to a mold press mold that does not require post-processing such as polishing on a surface to be molded, by press-molding a molding material such as glass with an upper mold and a lower mold subjected to precision processing, and this mold press mold It can apply to the manufacturing method of the optical element using this.

1 is a schematic cross-sectional view showing an embodiment of a mold press mold according to the present invention. It is a schematic plan view which shows an example of the mold press molding apparatus suitable for using the mold press molding die which concerns on this invention. It is explanatory drawing which shows process (1)-(4) in one Embodiment of the manufacturing method of the optical element which concerns on this invention. It is explanatory drawing which shows process (5)-(8) in one Embodiment of the manufacturing method of the optical element which concerns on this invention. It is explanatory drawing which shows process (9)-(12) in one Embodiment of the manufacturing method of the optical element which concerns on this invention. It is explanatory drawing which shows process (13)-(14) in one Embodiment of the manufacturing method of the optical element which concerns on this invention. In other embodiment of the manufacturing method of the optical element which concerns on this invention, it is explanatory drawing which shows the process corresponded to FIG. 5 (10), (11). FIG. 7 is an explanatory view showing steps corresponding to FIGS. 6 (13) and (14) in another embodiment of the method of manufacturing an optical element according to the present invention.

Explanation of symbols

10 Upper mold 11 Molding surface 20 Lower mold 21 Molding surface 30 Body mold 40 Bearing member 50 Molding material 51 Molded body 70 Mounting base 71 Opening P2 First heating chamber P3 Second heating chamber P4 Third heating chamber P5 Press chamber P6 First First slow cooling room P7 Second slow cooling room P8 Rapid cooling room

Claims (18)

A lower mold in which a molding surface having a convex surface is formed, and an upper mold in which a molding surface is formed on a surface opposite to the lower mold molding surface, and a molding material supplied on the lower mold is used as the upper mold A mold press molding apparatus for press molding between the lower mold and the lower mold,
Around the lower mold molding surface, an annular support member that supports the molding material is provided so as to protrude above the lower mold molding surface at a predetermined height ,
The support member supports the lower surface peripheral portion of the molding material at least at the upper edge on the inner peripheral surface side of the support member, and the molding material is formed so that the outer periphery of the molding material becomes an open space. A mold press mold characterized by being supported.   A body mold is provided in which the upper mold and the lower mold can be inserted from both ends, respectively, and the body mold regulates a horizontal relative position between the upper mold and the lower mold. Item 2. A mold press mold according to Item 1.   The mold press mold according to claim 1, wherein the support member is detachably provided. It said bearing member, a periphery of the lower mold molding surface, any one of claims 1 to 3, characterized in that it is placed on the stepped portion formed at a position lower than the lower mold molding surface 1 The mold press mold according to the item.   The mold press mold according to claim 4, wherein the support member has a vent hole between the lower mold forming surface and the step portion in the axial direction of the support member.   The mold press mold according to any one of claims 1 to 5, wherein the support member has a tapered inner periphery that decreases in diameter as the inner diameter decreases downward. Using a molding die having a lower die having a convex molding surface and an upper die having a molding surface opposite to the lower molding surface, a molding material is supplied onto the lower die. In the manufacturing method of the optical element to be press-molded,
Around the lower mold forming surface, a ring-shaped support member for supporting the molding material is provided so as to protrude above the lower mold forming surface at a predetermined height, and the lower surface side peripheral portion of the molding material Is supported by at least the upper edge on the inner peripheral surface side of the bearing member, and the molding material is supplied so that an open space is secured outside the peripheral edge of the molding material supported by the bearing member. Then, press molding is performed by bringing the upper mold and the lower mold relatively close to each other, and a method for producing an optical element.   The method for manufacturing an optical element according to claim 7, wherein the molding material has a convex curved surface. 8. The press molding is performed by regulating the relative position in the horizontal direction of the upper mold and the lower mold by a barrel mold in which the upper mold and the lower mold can be inserted from both ends. 9. The method for producing an optical element according to any one of 8 above. The optical element according to any one of claims 7 to 9 , wherein the molding material is supported by the support member so as to be in non-contact with the lower mold molding surface, and then press molding is performed. Manufacturing method. Ventilation holes are provided in the body mold and the support member, and the atmosphere between the molding material supported by the support member and the lower mold forming surface when the upper mold and the lower mold are relatively close to each other. gas, method of manufacturing an optical element according to any one of claims 7-10, characterized in that to release through the vent to the mold exterior. The forming material, method of manufacturing an optical element according to any one of claims 7 to 11, characterized in that it has a greater diameter than the optical element effective diameter. After the press molding method for manufacturing an optical element according to any one of claims 7 to 12, characterized in that performing the centering of removing outer peripheral portions of the resulting molded article. After press molding, the resulting molded product after removal from the mold together with the support member, according to any one of claims 7 to 13, characterized in that separating the support member and the molded body A method for manufacturing an optical element. Wherein as a bearing member, process for producing an optical element according to any one of claims 7-14 which is characterized by using a material having an inner periphery tapered to reduced diameter as the inner diameter goes downward. The molding material is preliminarily molded by dropping or flowing down molten glass on a receiving mold, or preformed by further shaping the glass lump after being dropped or dropped and separated. the method for manufacturing an optical element according to any one of claims 7 to 15, characterized in that those. The mold is transferred to a plurality of processing chambers including a heating chamber, a press chamber, and a cooling chamber, and each of the processing chambers is subjected to processing including heating, pressing, and cooling to be accommodated in the molding die. the method for manufacturing an optical element according to any one of claims 7-16 for the molding material, characterized in that it is press-molded. The press is started in a state in which the relative position between the molding surface of the lower mold and the support member does not change after supplying the molding material onto the lower mold. 2. A method for producing an optical element according to item 1.

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