JP2005314219A - Method and apparatus for molding optical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for molding an optical element, which is capable of precisely positioning (centering) the optical element at the center of a first mold even in case that the shapes of the optical element raw material and the mold accommodating the optical element raw material have a relationship of curved faces such as convex and concave surfaces. <P>SOLUTION: The apparatus is equipped with the first mold 40, the other mold 10, a cylindrical sleeve 20 which keeps the first and the other molds 40 and 10 facing each other, and positioning members 30, 30 and 30 which are inserted from the side wall of the sleeve 20 into the inside of the cylinder and at least movable on the mold surface 43 of the first mold 40, and structured to hold the optical element raw material M accommodated in the first mold 40 by these positioning members 30, 30 and 30. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical element molding method and molding apparatus, and in particular, even when the optical element material and the shape of a mold for housing the optical element material have a curved surface and a curved surface such as a convex surface or a concave surface, The present invention relates to a molding method and a molding apparatus for an optical element that can be accurately positioned (centered) in the center of the mold.

  Conventionally, an optical element material having a spherical or aspherical outer shape, such as a glass ball shape or a gob shape, has been used. When a convex or concave lens is molded by such an optical element material, the optical element is used. The material rolls on the mold surface that is concave or convex, and accurate centering cannot be performed.

Therefore, in Japanese Patent Laid-Open No. 2001-10826, an optical element that performs neutralization and centering at the same time by placing a glass ball-shaped optical element material on a lower mold surface through a glass material and blowing neutralization air onto the glass material. An element forming method and a forming apparatus have been proposed.
JP 2001-10826 (paragraph numbers [0011] to [0019], FIG. 1)

  However, in the conventional optical element molding method and molding apparatus described above, when the mold surface is concave, the glass ball-shaped optical element material can be positioned by the glass material, but when the mold surface is convex, There has been a problem that an optical element material having an outer shape such as a glass ball shape or a gob shape cannot be positioned such as a spherical surface or an aspherical surface.

  For this reason, when the mold surface is convex, it is necessary to prepare an expensive approximate shape material by polishing the concave surface that approximates the final molded product to be molded. However, there is a problem that it is not possible to use a glass ball-shaped or gob-shaped optical element material that is easy to control.

  The present invention has been made in view of the above problems, and even when the optical element material and the shape of a mold for housing the optical element material have a relationship between a curved surface and a curved surface such as a convex surface or a concave surface, the optical element is It is an object of the present invention to provide a molding method and molding apparatus for an optical element that can be accurately positioned in the center of a mold.

  In order to achieve the above object, an optical element molding method according to the present invention provides an optical element in a case where the shape of the optical element material and one mold for housing the optical element has a curved surface and a curved surface such as a convex surface or a concave surface. And a positioning step of holding the optical element material in the one mold and holding the optical element material by at least a positioning member capable of moving back and forth on the mold surface of the one mold. It is like that.

Preferably, after the positioning step, another mold corresponding to the one mold is closed, and the other mold is brought into contact with the positioning member in a process in which both molds are relatively close to each other. The molding step for molding the optical element material while retracting the positioning member, or after the positioning step, the other mold corresponding to the one mold is closed, and both molds are In the process of relatively approaching, a molding step is performed in which the deformed optical element material is brought into contact with the positioning member to mold the optical element material while retracting the positioning member.

  Preferably, after the positioning step, another mold corresponding to the one mold is closed, the optical element material is sandwiched between both molds, and then the positioning member is retracted, and the optical element material A molding process for molding the mold, or before the positioning process, the other mold corresponding to the one mold is closed, and the optical element material is sandwiched between the two molds. To do.

Preferably, in the positioning step, the optical element material is held by the positioning member so that the optical element material and the mold surface of the one mold are not in contact with each other.
In order to achieve the above object, the optical element molding apparatus according to the present invention has a relationship between a curved surface and a curved surface, such as a convex surface or a concave surface, when the shape of the optical element material and the mold for housing the optical element material is the same. An optical element molding apparatus to be used is provided with a positioning member that holds an optical element material accommodated in the one mold and can be moved back and forth on the mold surface of the one mold.

  Preferably, the one mold, another mold corresponding to the one mold, a cylindrical sleeve that holds the one mold and the other mold facing each other, and the sleeve The positioning member is inserted through the side wall into the cylinder and can move forward and backward on at least the mold surface of the one mold.

  Preferably, a guide inclined surface is provided at a distal end of the positioning member, and when the one mold and another mold corresponding thereto are brought relatively close to each other, the other mold is placed on the guide inclined surface. A configuration in which the positioning member is retracted by abutting and pushing, or a configuration in which the positioning member can be retracted by extruding the optical element material deformed by the relative approach of the one and another mold.

  Preferably, the thickness of the side wall of the sleeve is made larger than the protruding length of the positioning member protruding into the cylinder of the sleeve.

  According to the method and apparatus for molding an optical element according to the present invention, the optical element material can be positioned on a curved mold surface even if the shape of the optical element material and the mold is a curved surface. An optical element having a convex surface or a concave surface can be molded by using a general-purpose glass ball or gob-shaped optical element material as it is without processing the optical element material into a shape approximate to that of a molded product.

Hereinafter, an optical element molding method and molding apparatus according to an embodiment of the present invention will be described with reference to the drawings.
First, an optical element molding method and molding apparatus according to a first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an exploded perspective view showing a molding apparatus according to the first embodiment of the present invention, and FIG. 2 is a perspective view showing an assembled state of the molding apparatus. FIG. 3 is a partially enlarged view showing the operation of the positioning means during molding by the molding apparatus.

  In FIG. 1, a molding apparatus 1 according to the present embodiment is for press-molding a biconcave lens having spherical surfaces on the upper surface and the lower surface from an optical element material M that is a glass ball. The upper mold (other mold) 10, the sleeve 20, the three positioning members 30, 30, 30, the first lower mold 40, and the second lower mold 50 are arranged in order from. Hereinafter, for convenience of explanation, each component will be described in the order of the upper mold 10, the first lower mold (one mold) 40, the second lower mold 50, the sleeve 20, and the positioning members 30.

The upper mold 10 is for forming one side spherical surface of the biconcave lens as a molded product, and is configured to be pressable by an upper base of a press machine (not shown). The upper mold 10 is formed on a circular plate-shaped substrate portion 11 and cylindrical step portions 12 and 13 concentric with the circular plate portion 11 and having a diameter that is reduced in two steps.
A convex mold surface 14 for forming the spherical surface is provided on the lower end surface of the lowermost step 13.

  A contact edge 15 is formed on the outer edge of the convex mold surface 14. The contact edge 15 plays an important role in retracting each positioning member 30 during molding of the optical element material M. This will be described in detail later.

  The first lower mold 40 is for forming the other spherical surface of the biconcave lens, which is a molded product, and is placed or fixed on the lower base of the press machine while being centered with the upper mold 10. is there. In the first lower mold 40, a stepped portion 42 having the same diameter as that of the stepped portion 12 of the upper mold 10 is formed in the center of a disk-shaped substrate portion 41 having the same diameter as the substrate portion 11 of the upper mold 10. As a configuration. At the center of the upper surface of the stepped portion 42, a convex mold surface 43 for forming the spherical notch surface is provided.

  The second lower mold 50 is disposed between the upper mold 10 and the lower mold 40, and forms the side surface of the biconcave lens that is a molded product. The second lower mold 50 is an annular member having the same outer diameter as the stepped portions 12 and 42 of the upper mold 10 and the lower mold 40, and is substantially the same as the convex mold surfaces 14 and 43 on the inner peripheral surface thereof. An annular mold surface 51 having the same inner diameter is provided.

  The sleeve 20 is a thick cylindrical member, and holds the upper mold 10, the first lower mold 40, and the second lower mold 50 in a state of being combined with each other in a predetermined arrangement, and is a mold of the biconcave lens as a molded product. It forms the whole. That is, the upper and lower end surfaces of the sleeve 20 are contact surfaces 20a and 20b having the same diameter as the substrate portions 11 and 41 of the upper mold 10 and the first lower mold 40, respectively. The inner diameter is substantially the same as the outer diameters of the step portions 12 and 42 of the upper mold 10 and the first lower mold 40 and the second lower mold 50.

  Further, three insertion holes 21, 21, 21 having a substantially horizontal cross-sectional rectangle are formed in the middle of the height direction of the sleeve 20. Each insertion hole 21 is formed radially at 120 ° intervals toward the central axis of the sleeve 20, and three positioning members 30 are slidably inserted and held in each.

Here, in this embodiment, as shown in FIG. 3, the wall thickness L1 of the sleeve 20 is set to each insertion hole 2.
It is made longer than the protruding length L2 of the positioning member 30 inserted into 1. Thereby, the backward movement of each positioning member 30 described later is ensured.

  Each positioning member 30 is for positioning (centering) the optical element material M, which is a glass ball, on the convex mold surface 43 of the first lower mold 40, and has substantially the same dimensions as the insertion hole 21 of the sleeve 20. The main body 31 has a rectangular cross section.

  At the tip of the main body 31, there are a guide inclined surface 32 a that abuts the contact edge 15 of the upper mold 10 and a holding vertical surface 32 b that abuts the optical element material M when the optical element material M is molded. It is formed.

  In addition, a rectangular block-shaped stopper portion 33 is provided at the rear end of the main body portion 31. When the positioning member 30 is inserted through the insertion hole 21, the stopper portion 33 abuts against the outer wall surface of the sleeve 20 to restrict the insertion of the positioning member 30, and the holding vertical surface 32 b is disposed at the initial position. That is, a circle of diameter + several μm of the optical element material M is conceptually imagined on the center of the convex mold surface 43 of the first lower mold 40, and each of the stopper parts 33 is in contact with the outer wall surface of the sleeve 20. When the positioning member 30 is inserted through the insertion hole 21, each holding vertical surface 32 b is set at a position that makes point contact with the virtual circle.

  Next, an embodiment of a molding method of the present optical element using the molding apparatus 1 having the above configuration will be described with reference to FIGS.

  First, the assembly of the molding apparatus 1 will be described. In FIG. 1, the second lower mold 50 is placed on the stepped portion 42 of the first lower mold 40, and the stepped portion 42 and the second lower mold 50 are placed. The sleeve 20 is placed on the substrate portion 41 of the first lower mold 40 while being inserted into the cylinder. Then, each positioning member 30 is inserted into each insertion hole 21 of the sleeve 20 to obtain an assembly state shown in FIG. 2 (hereinafter referred to as an assembly).

  Next, the optical element material M, which is a glass ball, is placed on the convex mold surface 43 of the first lower mold 40. At this time, if the optical element material M is dropped aiming at approximately the center of the convex mold surface 43, the optical element material M is guided to the center of the convex mold surface 43 by the guide inclined surface 32 a of each positioning member 30. Then, each holding vertical surface 32b comes into contact with the vicinity of the equator of the optical element material M from three directions and is accurately positioned (centered).

  Next, the assembly and the upper mold 10 are heated by a heater (not shown), and when both reach a predetermined temperature, the mold is closed. Then, as shown in FIG. 3, as the convex mold surface 14 of the upper mold 10 and the convex mold surface 43 of the first lower mold 40 approach, the contact edge 15 of the upper mold 10 The positioning member 30 is pushed outward while sliding on the guide inclined surface 32 a of the positioning member 30, and each positioning member 30 is retracted to a space outside the step portion 13.

Thereafter, when the base plate portion 11 of the upper mold 10 and the contact surface 20a of the sleeve 20 contact each other, press molding of a biconcave lens having a spherical surface on the upper surface and the lower surface is completed.
According to the optical element molding method and molding apparatus of this embodiment, the optical element material M, which is a glass ball, is accurately positioned (centered) at the center of the convex mold surface 43 of the first lower mold 40. Therefore, a high-precision biconcave lens can be manufactured by press molding using an inexpensive glass ball as it is without using an expensive optical element material processed into an approximate shape as in the prior art.

In addition, a guide inclined surface 32a is provided at the tip of each positioning member 30, and when the optical element material M is formed, the contact edge 15 of the upper mold 10 is brought into contact with the guide inclined surface 32a so as to be interlocked therewith. Thus, each positioning member 30 can be automatically retracted.
Furthermore, since the wall thickness L1 of the sleeve 20 is larger than the protruding length L2 of the positioning member 30 inserted into each insertion hole 21, each positioning member 30 is held in a stable state without rattling into the insertion hole 21. As a result, the downward pressing force of the contact edge 15 of the upper mold 10 always acts on the positioning members 30 in the horizontal direction, and the positioning members 30 can be reliably retracted.

  Next, an optical element molding method and molding apparatus according to a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a partially enlarged view showing the operation of the positioning means during molding by the molding apparatus. In the following embodiments, the same portions as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

In FIG. 4, the molding apparatus 2 according to the present embodiment is provided with insertion holes 22, 22, 22 that are inclined downward on the outer side of a circular cross section in the sleeve 20, and pin-like positioning members 60, 60, 60 are provided in the respective insertion holes 22. Each is inserted.
Each positioning member 60 has a main body portion 61 having a circular cross section having substantially the same dimensions as the insertion hole 22 of the sleeve 20. The main body 61 has a light and thin round bar shape, and is provided with a hemispherical holding surface 62 at the front end and a rectangular block-like stopper 63 at the rear end.

  When the positioning member 60 is inserted through the insertion hole 22, the stopper portion 63 abuts against the outer wall surface of the sleeve 20 to restrict the insertion of the positioning member 60 and arranges the holding surface 62 at the initial position. Similar to the first embodiment, a circle of diameter-several μm of the optical element material M is conceptually imagined on the center of the convex mold surface 43 of the first lower mold 40, and the stopper portion 63 is the outer wall surface of the sleeve 20. When the positioning members 60 are inserted through the insertion holes 22 until they come into contact with each other, the respective holding surfaces 62 are set so as to make point contact with the virtual circle.

  In the present embodiment, the second lower mold 50 as in the first embodiment does not exist, and the side surface of the optical element material M is not molded.

  Next, an embodiment of a molding method of the present optical element using the molding apparatus 2 having the above configuration will be described with reference to FIG.

  First, as in the first embodiment, the sleeve 20 is placed on the substrate portion 41 (see FIG. 1) of the first lower mold 40, and the three stopper portions 63 are passed through the insertion holes 22 of the sleeve 20, respectively. Insert and assemble (hereinafter referred to as assembly).

  Next, the optical element material M, which is a glass ball, is placed on the convex mold surface 43 of the first lower mold 40. Then, the holding surface 62 of each positioning member 60 is point-contacted from the three lower diagonal directions below the equator of the optical element material M, and is accurately positioned (centered). Thereby, this shaping | molding apparatus 1 comprises an assembly as shown in FIG.

  Next, the assembly and the upper mold 10 are heated by a heater (not shown), and when both reach a predetermined temperature, the mold is closed. Then, as the convex mold surface 14 of the upper mold 10 and the convex mold surface 43 of the second lower mold 40 approach each other, the optical element material M is press-molded, deformed and pushed outward. However, each positioning member 60 is retracted to the space outside the step portion 13 via the holding surface 62.

  Thereafter, when the substrate portion 11 of the upper mold 10 and the contact surface 20a of the sleeve 20 come into contact with each other (see FIG. 1), press molding of the biconcave lens is completed.

  According to such a molding method and molding apparatus for an optical element, as in the first embodiment, the optical element material M, which is a glass ball, is accurately positioned at the center of the convex mold surface 43 of the first lower mold 40. In addition, the positioning members 60 can be automatically retracted by the deformed optical element material M. Thereby, the contact edge 15 of the upper die 10 can be retracted without being brought into contact with each positioning member 60, and the life can be extended by preventing the first lower die 40 and each positioning member 60 from being worn. it can.

  Next, an optical element molding method and molding apparatus according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a perspective view showing an assembling state of a molding method and a molding apparatus for carrying out the molding method according to the third embodiment of the present invention. FIG. 6 is a partially enlarged view showing the operation of the positioning means during molding by the molding apparatus. In the following embodiments, the same portions as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  In these drawings, the molding apparatus 3 according to the present embodiment includes three positioning members 70, 70, 70 each including a holding block 71 having a rectangular cross section and a holding sphere 72, and each holding sphere 72 is used as an optical glass. The element material M is configured to be positioned at the center of the convex mold surface 43 of the first lower mold 40.

  The pressing block 71 has a concave surface portion 71a on the front surface and a stopper portion 71b on the back surface. On the other hand, the holding sphere 72 is a metal sphere or ceramic sphere having a diameter slightly smaller than the height of the holding block 71.

  On the other hand, the sleeve 20 is formed with three insertion holes 23, 23, 23 having a substantially horizontal sectional rectangle. A stepped portion 23 a having a height substantially equal to the diameter of the holding sphere 72 is formed on the inner diameter side of the sleeve 20 in each insertion hole 23.

  As shown in FIG. 5, when the sleeve 20 is placed on the substrate portion 41 of the first lower mold 40 and the holding sphere 72 and the holding block 71 are inserted into the insertion holes 22 of the sleeve 20 in this order, When the stopper portion 71b comes into contact with the outer wall surface of the sleeve 20, the holding block 71 places the holding sphere 72 at the initial position. That is, a circle of diameter + several μm of the optical element material M is conceptually imagined on the center of the convex mold surface 43 of the first lower mold 40 until each stopper portion 71b contacts the outer wall surface of the sleeve 20. When the holding block 71 is inserted, each holding sphere 72 is set to a position where it makes point contact with the virtual circle.

Next, an embodiment of a molding method of the present optical element using the molding apparatus 3 having the above configuration will be described with reference to FIGS. 5 and 6.
First, as in the first embodiment, the sleeve 20 is placed on the base plate portion 41 of the first lower mold 40, and three sets of holding spheres 72 and pressing blocks 71 are arranged in the respective insertion holes 23 of the sleeve 20. These are inserted to form the assembly shown in FIG.

Next, the optical element material M, which is a glass ball, is placed on the convex mold surface 43 of the first lower mold 40. Then, each holding sphere 72 is accurately positioned (centered) by making point contact from the three directions near the equator of the optical element material M.
Next, the assembly and the upper mold 10 are heated by a heater (not shown), and when they reach a predetermined temperature, both are closed. Then, as the convex mold surface 14 of the upper mold 10 and the convex mold surface 43 of the second lower mold 40 approach each other, the optical element material M is press-molded, deformed and pushed outward. However, the holding sphere 72 and the holding block 71 are retracted to a space outside the step portion 13.

Thereafter, when the substrate portion 11 of the upper mold 10 and the contact surface 20a of the sleeve 20 come into contact with each other (see FIG. 1), press molding of the biconcave lens is completed.
According to such a molding method and molding apparatus for an optical element, as in the first embodiment, the optical element material M, which is a glass ball, is accurately positioned at the center of the convex mold surface 43 of the first lower mold 40. In addition to this, similarly to the second embodiment, the holding sphere 72 and the holding block 71 constituting each positioning member 70 can be automatically retracted by the deformed optical element material M. Accordingly, the positioning members 70 can be retracted without contacting the contact edge 15 of the upper mold 10 with the positioning members 70, thereby preventing wear of the first lower mold 40 and the positioning members 70. Long life can be achieved.

In addition to this, according to the molding method and molding apparatus of the optical element of the present embodiment, only the three holding spheres 72 are in contact with the optical element material M. Therefore, these holding spheres 72 deteriorated over many years of use are replaced. Only the holding block 71 can be used semipermanently.
Next, an optical element molding method and molding apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 7 is a perspective view showing an assembled state of the molding apparatus according to the fourth embodiment of the present invention. FIG. 8 is a partially enlarged view showing the operation of the positioning means during molding by the molding apparatus. In the following embodiments, the same parts as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

In FIG. 7, the molding apparatus 4 of the present embodiment is configured so that the optical element material M, which is a glass ball, is projected from two directions by the first and second positioning means 80 and 90 having different configurations. The configuration is such that it is positioned at the center of the surface 43.
Like the positioning member 30 in the first embodiment, the first and second positioning members 80 and 90 have main body portions 81 and 91 having a rectangular cross section, and are formed with guide inclined surfaces 82 and 92 at their tips, and thereafter A rectangular block-like stopper 83, 93 is provided at the end. However, unlike the first positioning member 80, support pieces 94 are provided at the lower ends on both sides of the second positioning member 90. At the tip of each support piece 94, a holding edge 94a that is inclined outward from the tip of the main body 91 is formed.

  The sleeve 20 is formed with two insertion holes 24 and 25 having a substantially horizontal cross section. The insertion hole 24 for inserting the first positioning member 80 has substantially the same vertical and horizontal dimensions as the main body portion 81. On the other hand, the insertion hole 25 for inserting the second positioning member 90 has the same height as the main body 91 and a total width of the main body 91 and the support pieces 94, 94.

  As shown in FIG. 7, when the sleeve 20 is placed on the substrate portion 41 of the first lower mold 40 and the first and second positioning members 80 and 90 are inserted into the insertion holes 24 and 25 of the sleeve 20. When the stopper portions 83 and 93 come into contact with the outer wall surface of the sleeve 20, the guide inclined surfaces 82 and 92 and the holding edges 94a and 94a are arranged at the initial positions.

  That is, a circle of diameter-several μm of the optical element material M is conceptually imagined on the center of the convex mold surface 43 of the first lower mold 40, and the stopper portions 83 and 93 abut against the outer wall surface of the sleeve 20. Until the positioning members 80 and 90 are inserted into the insertion holes 24 and 25, the guide inclined surfaces 82 and 92 and the holding edges 94a and 94a are set so as to be in point contact with the virtual circle. It is.

  Further, the initial positions of the guide inclined surfaces 82 and 92 and the holding edges 94a and 94a are also positions for positioning the optical element material M on the center of the convex mold surface 43 of the first lower mold 40. In the present embodiment, as shown in FIG. 8, the guide inclined surfaces 82 and 92 and the holding edges 94 a and 94 a are in contact with the optical element material M at three points from two directions near the equator of the optical element material M. A gap S is formed between the first lower mold 40 and the convex mold surface 43.

  The configuration for forming the gap S between the optical element material M and the first lower mold 40 is not limited to the fourth embodiment, and the optical element molding method according to the first to third embodiments and The present invention can also be applied to a molding apparatus.

  Next, an embodiment of the molding method of the present optical element using the molding apparatus 4 having the above configuration will be described with reference to FIGS.

  First, as in the first embodiment, the sleeve 20 is placed on the substrate portion 41 of the first lower mold 40, and the first and second positioning members 80, 90 are placed in the insertion holes 24, 25 of the sleeve 20. The assembly shown in FIG.

  Next, the optical element material M, which is a glass ball, is placed on the convex mold surface 43 of the first lower mold 40. At this time, if the optical element material M is dropped aiming at the approximate center of the convex mold surface 43, the optical element material M is projected by the guide inclined surfaces 82, 92 of the first and second positioning members 80, 90. The guide inclined surfaces 82, 92 and the holding edges 94a, 94a are guided near the equator of the optical element material M at three points from two directions. The optical element material M is accurately positioned at the center on the convex mold surface 43 of the first lower mold 40 while forming a gap S between the first lower mold 40 and the convex mold surface 43.

  Next, the assembly and the upper mold 10 are heated by a heater (not shown), and when both reach a predetermined temperature, the mold is closed. Then, as the convex mold surface 14 of the upper mold 10 and the convex mold surface 43 of the second lower mold 40 approach each other, the optical element material M is press-molded, deformed and pushed outward. However, the first and second positioning members 80 and 90 are retracted to the space outside the step portion 13.

Thereafter, when the substrate portion 11 of the upper mold 10 and the contact surface 20a of the sleeve 20 come into contact with each other (see FIG. 1), press molding of the biconcave lens is completed.
According to such a molding method and molding apparatus for an optical element, as in the first embodiment, the optical element material M, which is a glass ball, is accurately positioned at the center of the convex mold surface 43 of the first lower mold 40. In addition, the first and second positioning members 80 and 90 can be automatically retracted by the deformed optical element material M as in the second embodiment. Accordingly, the contact edge 15 of the upper mold 10 can be retracted without contacting the first and second positioning members 80 and 90, and the first lower mold 40 and the first and second positioning members 80 can be retracted. , 90 can prevent the wear out and can extend the service life.

  In addition, according to the molding method and molding apparatus of the optical element of the present embodiment, when the assembly and the upper mold 10 are heated by the heater, the optical element material M is made convex by the first lower mold 40. Since it can be in a non-contact state with the mold surface 43 (see the gap S in FIG. 8), a molded product and gold caused by a volatile component of the optical element material M generated by contact with the convex mold surface 43 Mold fogging can be prevented.

  Next, an optical element molding method and molding apparatus according to a fifth embodiment of the present invention will be described with reference to FIGS. 9, 10A, 10B, and 11. FIG. FIG. 9 is a partial cross-sectional perspective view showing the assembled state of the molding apparatus according to the fifth embodiment of the present invention. FIGS. 10A and 10B are partial sectional perspective views showing a state in which the optical element material is positioned in the molding apparatus. FIG. 11 is a partial cross-sectional perspective view showing the operation after positioning the optical element material on the molding apparatus. In the following embodiments, the same portions as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the first to fourth embodiments, each positioning member is automatically retracted in conjunction with the operation of moving the upper mold 10 toward the lower mold 40. However, in this embodiment, the upper mold 10 is moved. Without interlocking, each positioning member 100 was retracted and extracted from the sleeve 20. That is, in this embodiment, each positioning member 100 is extracted from the sleeve 20 when the positioned optical element material M is sandwiched between the upper mold 10 and the lower mold 40.

  Each positioning member 100 of the present embodiment is configured such that a small-diameter columnar pin member having a holding surface 102 is coupled to a larger-diameter columnar stopper portion 103, and the positioning member 30 of the first embodiment. Such a guide inclined surface 32a is not formed.

  Next, an embodiment of the present optical element material molding method using the molding apparatus 5 having the above-described configuration will be described with reference to FIGS. 9, 10 (a), 10 (b), and 11.

  First, as in the first embodiment, the sleeve 20 is placed on the substrate portion 41 (see FIG. 9) of the lower mold 40, and the three positioning members 100 are inserted through the insertion holes 21 of the sleeve 20, respectively. Assemble (hereinafter referred to as an assembly). At this time, the stopper 103 of each positioning member 100 is positioned by contacting the outer peripheral surface of the sleeve 20.

  Next, the optical element material M, which is a glass ball, is placed on the convex mold surface 43 of the lower mold 40. Then, the optical element material M is held by point contact from three directions by the holding surface 102 of each positioning member 100 and is accurately positioned (centered). Thus, the assembly shown in FIG. 9 is configured.

  Then, the optical element material M in a positioned state is sandwiched between the upper mold 10 and the lower mold 40 so as not to move, and then each positioning member 100 is retracted and extracted from the sleeve 20. Extraction of each positioning member 100 may be performed, for example, by grasping the stopper portion 103 of each positioning member 100 with an arm or hand (not shown).

  In the present embodiment, the optical element material M is positioned by the positioning members 100, and then the upper mold 10 is inserted into the sleeve 20, and the optical element material M is sandwiched between the upper mold 10 and the lower mold 40. After the optical element material M is sandwiched between the upper mold 10 and the lower mold 40 in the sleeve 20 (at this time, the optical element member M is in a shifted state), the optical element member M is moved to the upper mold 10 and the lower mold. The optical element material M may be positioned by inserting the positioning members 100 into the sleeve 20 while being sandwiched between the optical element material M and the sleeve 40.

  Next, the assembly and the upper mold 10 are heated by a heater (not shown), and when both reach a predetermined temperature, the mold is closed. Thereafter, the press molding of the biconcave lens is completed when the substrate portion 11 of the upper mold 10 and the contact surface 20a of the sleeve 20 contact each other.

  According to the molding method and molding apparatus of the optical element of this embodiment, the optical element material M, which is a glass ball, is accurately centered on the convex mold surface 43 of the lower mold 40 as in the first embodiment. If the combination of the shapes of the upper mold 10, the lower mold 40, and the optical element material M is not unstable, the assembly can be formed by only one positioning before press molding. Therefore, it is not necessary to position each time the upper mold 10 is moved, so that a molded product can be produced at a low cost.

  In addition, the shaping | molding method and shaping | molding apparatus of the optical element of this invention are not limited to each embodiment mentioned above. For example, in each of the above-described embodiments, a case has been described in which a biconcave lens having spherical notches on the upper surface and the lower surface is press-molded from the optical element material M, which is a glass ball. The element molding method and the molding apparatus are such that when the shape of the optical element material and the mold is curved and curved, for example, when a convex lens is molded from a glass ball-shaped optical element material, a gob-shaped optical element material is used. Therefore, the present invention can be widely applied to molding a convex or concave lens.

  In each of the above-described embodiments, the optical element material M is illustrated as being held from three or two directions by a plurality of positioning members. However, the present invention is not limited to this. It is also possible to hold the element material M from four directions. Further, if the central axis of the molding apparatus 4 shown in FIG. 7 is inclined toward the second positioning member 90, only the second positioning member 90 can be It is also possible to hold the optical element material M. In this case, the first positioning member 80 can be omitted.

It is a disassembled perspective view which shows the shaping | molding apparatus based on 1st Embodiment of this invention, It is a perspective view which shows the assembly state of this shaping | molding apparatus. It is the elements on larger scale which show operation | movement of the positioning means in this shaping | molding apparatus. It is the elements on larger scale which show operation | movement of the positioning means in the shaping | molding apparatus which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the assembly state of the shaping | molding apparatus which concerns on 3rd Embodiment of this invention. It is the elements on larger scale which show operation | movement of the positioning means in this shaping | molding apparatus. It is a perspective view which shows the assembly state of the shaping | molding apparatus which concerns on 4th Embodiment of this invention. It is the elements on larger scale which show operation | movement of the positioning means in this shaping | molding apparatus. It is a fragmentary sectional perspective view which shows the assembly state of the shaping | molding apparatus which concerns on 5th Embodiment of this invention. FIGS. 9A and 9B are partial cross-sectional perspective views showing a state in which an optical element material is positioned in the molding apparatus. It is a fragmentary sectional perspective view which shows the operation | movement after positioning an optical element raw material to the said shaping | molding apparatus.

Explanation of symbols

1 Molding device 10 Upper mold (other molds)
DESCRIPTION OF SYMBOLS 11 Substrate part 12, 13 Step part 14 Convex type | mold surface 15 Contact edge part 20 Sleeve 20a, 20b Contact surface 21 Insertion hole 30 Positioning member 31 Main body part 32a Guide inclined surface 32b Holding | maintenance vertical surface 33 Stopper part 40 1st bottom Mold (one mold)
DESCRIPTION OF SYMBOLS 41 Substrate part 42 Convex type | mold surface 50 2nd lower mold | type 51 Annular type | mold surface M Optical element raw material 2 Molding apparatus 22 Insertion hole 60 Positioning member 61 Main body part 62 Tapered surface 63 Stopper part 3 Molding apparatus 23 Insertion hole 23a Contact part 70 Positioning member 71 Holding block 71a Concave surface portion 71b Stopper portion 72 Holding sphere 4 Molding device 24 First insertion hole 25 Second insertion hole 80 First positioning member 81 Main body portion 82 Guide inclined surface 83 Stopper portion 90 Second positioning member 91 Main body portion 92 Guide inclined surface 93 Stopper portion 94 Support piece 94a Holding edge 100 Positioning member 102 Holding surface 103 Stopper portion S Gap

Claims (11)

A method of molding an optical element when the shape of the optical element material and the mold that accommodates the optical element has a relationship between a curved surface such as a convex surface or a concave surface and a curved surface,
An optical element comprising a positioning step of accommodating an optical element material in the one mold and holding the optical element material by a positioning member capable of moving forward and backward on at least the mold surface of the one mold. Molding method.   After the positioning step, the other mold corresponding to the one mold is closed, and in the process in which both molds are relatively close to each other, the other mold is brought into contact with the positioning member, The optical element molding method according to claim 1, further comprising a molding step of molding the optical element material while retracting the positioning member.   After the positioning step, the other mold corresponding to the one mold is closed, and the deformed optical element material is brought into contact with the positioning member in a process in which both molds are relatively approached, The optical element molding method according to claim 1, further comprising a molding step of molding the optical element material while retracting the positioning member.   After the positioning step, another mold corresponding to the one mold is closed, the optical element material is sandwiched between both molds, the positioning member is retracted, and the optical element material is molded. The method for molding an optical element according to claim 1, further comprising a molding step to be performed.   2. The optical element molding method according to claim 1, wherein, before the positioning step, another mold corresponding to the one mold is closed, and the optical element material is sandwiched between the two molds. .   The optical element material is held by the positioning member so that the optical element material and the mold surface of the one mold are not in contact with each other in the positioning step. A method for molding an optical element according to claim 1. An optical element molding apparatus used when the shape of an optical element material and a mold that accommodates the optical element material has a relationship between a curved surface such as a convex surface or a concave surface and a curved surface,
An optical element molding apparatus comprising a positioning member that holds an optical element material accommodated in the one mold and is capable of moving back and forth on at least the mold surface of the one mold. Said one mold,
Another mold corresponding to the one mold,
A cylindrical sleeve that holds these one and other molds facing each other;
The optical element molding apparatus according to claim 7, further comprising: a positioning member that is inserted into a cylinder from a side wall of the sleeve and is capable of advancing and retreating at least on the mold surface of the one mold.   A guide inclined surface is provided at the tip of the positioning member, and when the one mold and another mold corresponding thereto are brought relatively close to each other, the other mold comes into contact with the guide inclined surface. 9. The optical element molding apparatus according to claim 7, wherein the optical element is pushed out to retract the positioning member.   10. The optical element molding apparatus according to claim 7, wherein the positioning member can be retracted by extruding the optical element material deformed by relative approach of the one and another mold. The apparatus for molding an optical element according to any one of claims 8 to 10, wherein a thickness of a side wall of the sleeve is larger than a protruding length of the positioning member protruding into the cylinder of the sleeve.

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