JP2002154833A - Method and device for manufacturing optical element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for manufacturing optical elements such that optical elements in a desired form having no orange peel or cracks can be manufactured with good productivity and that the device can be minimized or the cost for the optical element can be reduced. SOLUTION: Fused glass 1 is dropped as spheric glass drops 4 from an outlet nozzle 3 attached to the lower part of a melting crucible 2 and is made to tumble and cooled on a tumbling jig 6 having a trough-like inclined tumbling face while keeping the spheric form. The cooled spheric material 4a for an optical element is directly put into the die 7 for an optical element disposed at the terminal point of the tumbling jig 6 and pressed to form an optical element 9 in a desired form.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element used for an optical apparatus, and more particularly to a method and an apparatus for manufacturing a glass molded lens used for an optical system of a pickup of an optical disk apparatus and an imaging camera. .

[0002]

2. Description of the Related Art In recent years, optical elements such as lenses and prisms are manufactured by grinding and polishing an optical element material such as glass instead of a machining method for manufacturing the optical element material. A number of pressure molding methods have been proposed in which the material is heated and softened, and then pressed and molded. This pressure molding method,
Generally, a reheat press method is used in which an optical element material is preliminarily processed into a predetermined shape, supplied between a pair of upper and lower molds, heated, and pressed.

When a precise optical element is formed by this reheat press method, the shape, surface smoothness, and weight accuracy of the optical element material are very important factors, and a ball glass material (rice grain or millet grain) has hitherto been used. Glass material) and a cylindrical glass material (a glass rod cut short in a cylindrical shape) have been used. However, since productivity, cost, and the like have become important, the molten glass melted in the crucible is dropped from an outflow nozzle and cooled by a receiving jig (not shown). ) Is used as the optical element material. In addition, there is a direct press method in which the dropped glass droplet is directly dropped into an optical element molding die and molded under pressure to produce an optical element.

[0004] As a specific example of the conventional direct press method, for example, a method disclosed in Japanese Patent Application Laid-Open No. 4-149032 will be described with reference to FIG. In FIG. 5, a molten glass 51 is stored in a melting furnace 50,
The molten glass 51 is dropped from an outflow nozzle 50a provided at a lower portion of the melting furnace 50 to form a glass droplet. Then, the glass droplets are allowed to fall naturally onto the previously heated thermal processing jig 53. Then, the glass droplet is transferred to the thermal processing jig 53.
The gob 52 is formed above. The gob 52 has a hemispherical free surface 52a and a contact surface 52b with the upper surface of the thermal processing jig. Since the free surface 52a is formed by the surface tension of the molten glass, it is a very good mirror surface. on the other hand,
The contact surface 52b becomes a wrinkled rough surface (a surface having irregularities like an orange surface skin, hereinafter referred to as an orange peel) due to thermal shrinkage due to a temperature difference from the thermal processing jig.

Thereafter, the gob 52 is cooled by a cooling stage 56 to a temperature below the softening point. In the reversing stage 56a, the gob 52 is reversed. , Next heating stage 5
7a, the contact surface 52b of the gob 52 with the thermal processing jig
Is heated using a heater 57 and softened to a mirror surface formed by surface tension. Then, the gob 52 is cooled again by the cooling stage 58. That is, the same process is performed twice in order to keep the state of both surfaces of the gob 52 at the time of press molding. Thereafter, the gob 52 is moved to the optical element molding dies 54a,
The optical element 55 is obtained by being pressed by 4b to form a desired shape, and then gradually cooled.

[0006] The optical element 55 thus formed has a desired shape, has an optical mirror surface, and is free from bubbles, scratches, and the like.
Alternatively, no defect such as peeling marks is observed, and a good product is obtained. The optical element obtained by the direct press method can obtain an optical element at a relatively low cost as compared with an optical element molding method in which two steps of manufacturing a glass material and molding an optical element are performed.

[0007]

However, in the direct press method described above, it is necessary to drop a glass droplet onto a thermal processing jig at a high temperature or to carry out a repetitive heating and cooling process. Has the following problems. That is, when the glass droplets are dropped directly on the thermal processing jig 53, the life of the thermal processing jig 53 may be shortened because the molten glass droplets are received at a very high temperature. Also, in order to prevent orange peel generated on the contact surface 52b of the gob 52 with the thermal processing jig 53,
If the temperature of the thermal processing jig 53 is raised to 550 ° C., which is the softening point of the glass, the life is further shortened.

Further, although the gob 52 is inverted, the surface in contact with the thermal processing jig 53 is constant, so that the entire surface is not uniformly cooled. For this reason, there is a possibility that the orange peel problem may occur in the free surface 52a which is a free surface. On the other hand, when the heating and cooling steps are repeated, a series of operations such as production of glass material and molding of an optical element can be performed continuously. No. Therefore, there has been a problem that it is not satisfactory in terms of cost reduction or downsizing of the apparatus.

An object of the present invention is to provide a method for manufacturing an optical element capable of uniformly quenching the surface of a glass droplet to a constant temperature and introducing an optical element material having good sphericity into an optical element molding die. It is to provide the manufacturing apparatus. Another object of the present invention is to provide a manufacturing method and a manufacturing apparatus for reducing the damage to an optical element molding die, reducing the size of the apparatus, and obtaining an optical element with good productivity and low cost. .

[0010]

In order to solve the above-mentioned problems, a method of manufacturing an optical element according to the present invention comprises melting a glass material with a melting crucible and forming the glass material at the tip of an outflow nozzle provided below the melting crucible. Dropping the dropped glass droplets to form a spherical glass droplet, by rolling while maintaining the spherical shape of the dropped glass droplet, the surface temperature is uniformly determined by a predetermined time-temperature curve. A step of producing a spherical optical element material by cooling to a temperature of, and a step of immediately putting the spherical optical element material into an optical element molding die to produce an optical element of a desired shape. . In the manufacturing method having the above-described configuration, it is preferable that the surface temperature of the spherical glass droplet that has fallen be rapidly cooled between 400 ° C and 600 ° C.

According to the method of manufacturing an optical element, since the dropped glass droplet is rolled and uniformly cooled in all directions, an optical element material having excellent sphericity can be put into the optical element molding die. . Further, since the surface temperature of the optical element material is cooled and charged into the optical element molding die, damage to the optical element molding die can be reduced. Further, stages for each step such as inversion and surface re-melting, which are required in the conventional method, are not required, and the manufacturing apparatus can be reduced in size, so that an optical element can be manufactured with excellent productivity and at low cost.

According to another aspect of the present invention, there is provided a method of manufacturing an optical element, comprising melting a glass material with a melting crucible and dropping a glass droplet formed at the tip of an outflow nozzle provided below the melting crucible. Forming a spherical optical element material by rolling the surface temperature to a temperature lower than the softening point of the glass material and cooling it while maintaining the spherical shape of the dropped spherical glass droplet. Step, rolling the spherical optical element material again to a temperature near the softening point of the glass surface to raise the temperature, and immediately putting the optical element material heated to a temperature near the softening point into an optical element molding die and pressing To produce an optical element having a desired shape.

According to this method of manufacturing an optical element, the temperature of the glass surface and the inner surface of the glass can be made uniform by once cooling the surface temperature and then raising it again.
Therefore, an optical element material having excellent sphericity can be charged into an optical element molding die, and an optical element material having extremely uniform surface and inner surface temperatures can be charged into the optical element molding die. As a result, orange peel when pressed,
The occurrence of cracks, stress, and the like can be prevented, and the optical element can be manufactured with good productivity at low cost.

The apparatus for manufacturing an optical element according to the present invention comprises a molten crucible for melting a glass material, an outflow nozzle provided below the molten crucible to drop the molten glass material into spherical glass droplets, and an outflow nozzle. Rolling cooling means for forming a spherical optical element material by rolling and cooling the dropped glass droplets, and optical element molding for molding the optical element material disposed at the end point of the rolling cooling means It has a mold.

According to the manufacturing apparatus of this configuration, since the dropped spherical glass droplet can be rolled and cooled, an optical element material having excellent sphericity can be immediately poured into the optical element molding die. In addition, a stage such as inversion and remelting of the surface is not required, and the size of the apparatus can be reduced.

According to another aspect of the present invention, there is provided an apparatus for manufacturing an optical element, wherein the rolling cooling means has a trough-shaped rolling jig in which the cross section for receiving the glass droplet is curved and the whole is inclined. It is characterized by being formed by. In addition, at least the surface of the rolling jig that comes into contact with the optical element material has a high thermal conductivity equal to or higher than that of cemented carbide or vitreous carbon, and is preferably formed of a material having excellent heat dissipation. desirable. Furthermore, it is desirable to form with a material with poor wettability with glass. Vitreous carbon has properties close to crystals, but is amorphous carbon and has mirror-like properties.

According to the manufacturing apparatus having this configuration, the spherical glass element material can be easily cooled by rolling down the dropped glass droplet on the rolling jig, and the spherical optical element material can be formed at the end point. It can be easily put into the arranged optical element molding die.

According to still another aspect of the present invention, there is provided an optical element manufacturing apparatus according to the above-mentioned configuration, wherein the rolling cooling means is capable of adjusting the temperature for receiving the dropped glass droplets and rotating horizontally. It is characterized by being formed with a receiving jig in a shape. At least the surface of the receiving jig that comes into contact with the glass droplets is desirably formed of a material having a high thermal conductivity equal to or higher than that of a cemented carbide or vitreous carbon and having excellent heat dissipation. . According to the manufacturing apparatus having this configuration, the installation space for the rolling cooling jig can be reduced, and the apparatus can be downsized.

According to still another aspect of the present invention, there is provided an apparatus for manufacturing an optical element according to the above-mentioned configuration, wherein the rolling cooling means has a trough-like shape in which a cross section for receiving a glass droplet is curved and the whole is inclined. A first rolling jig and a gutter-shaped temperature-adjustable second rolling jig disposed at an end point of the first rolling tool. Preferably, the second rolling jig has a temperature control mechanism capable of raising the temperature to near the softening of the glass material. Further, it is preferable that the second rolling jig is a heating jig formed of a porous material, and the optical element material moving on the heating jig is heated by jetting a heated gas.

According to the manufacturing apparatus of this configuration, the surface of the dropped glass droplet is rolled below the softening point on the first rolling jig to rapidly cool the surface temperature to obtain the optical element material. After
The optical element material is once again moved on a heating jig provided with a slope of a porous material from which a high-temperature gas can be ejected, and the temperature is raised to near the glass softening point. Thereby, by making the temperature of the surface and the inner surface of the optical element material uniform, an optical element material having excellent sphericity and a small temperature difference between the inside and the outside can be put into the optical element molding die. Furthermore, since the temperature is increased by ejecting a high-temperature gas, there is no deposit, and an optical element material having extremely uniform surface and inner surface temperatures can be provided. As a result, it is possible to prevent the occurrence of orange peel, cracks, and the like at the time of press molding, so that an optical element can be manufactured with good productivity and at low cost.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the apparatus for manufacturing an optical element according to the present invention will be described below with reference to the accompanying drawings.

Embodiment 1 FIG. 1 is a sectional view of an optical device manufacturing apparatus according to Embodiment 1 of the present invention, and FIG. 2 is a cross-sectional view of an optical element manufactured by the manufacturing apparatus according to Embodiment 1 of the present invention. FIG.

In FIG. 1, a platinum glass melting crucible 2 has an open upper end and an outflow nozzle 3 at the center of the bottom surface. Heater 8 provided on the outer periphery of molten crucible 2
The temperature of the molten crucible 2 is raised to melt the glass material 1 filled in the molten crucible 2. In this way, the molten glass material 1 is stored in the molten crucible 2, and a certain amount of spherical glass droplets 4 is discharged from the outflow nozzle 3 having a predetermined diameter by the balance between the surface tension and the mass of the molten glass. It is dripped.

On the other hand, place the gutter-like rolling jig 6 which is temperature controlled by the heater 8a inclined length 150mm at a falling distance L ₁ from the end face of the outlet nozzle 3 of the melting crucible 2, rolling jig The thin film member 5 having excellent heat resistance is placed on the surface portion 6. Fall distance _{L 1} at this time was set to 150 mm. Then, at the end point of the rolling jig 6, a temperature adjusting device 8b is provided.
Is disposed.

Here, as the glass material 1, for example,
Preferably, barium borosilicate glass is used. The reason is that this glass can be molded at 400 ° C. to 600 ° C. and is easy to mold. As the thin film member 5, a film sheet of, for example, graphite (having a thermal conductivity of 300 W / (m · K) or more, high heat resistance) having a thickness of 0.1 mm was used.

A method for manufacturing an optical element by the apparatus for manufacturing an optical element according to the first embodiment will be described with reference to FIG. In FIG. 1, a solid glass material 1 to be melted is put into a melting crucible 2. Thereafter, the temperature of the melting crucible 2 is increased to 1200 ° C. by the heater 8 to melt the glass material 1. Then, the molten glass material 1 is supplied to the outflow nozzle 3
A spherical glass droplet 4 having a diameter of about 1 to 5 mm is formed by the surface tension of the glass itself at the front end of the glass droplet.
Due to the balance between the mass of the glass droplet 4 and the surface tension, the glass droplet 4 falls by a falling distance L ₁ and sequentially falls on the thin film member 5 placed on the rolling jig 6.

The dropped glass droplet 4 rolls on the inclined thin film 5 of the rolling jig 6 adjusted to a predetermined temperature, and the surface is uniformly cooled to a predetermined temperature, that is, 400 to 600 ° C. Is done. When rolling, the surface of the glass droplet contacts the air almost uniformly, so that the surface is uniformly cooled. The glass droplet 4 cooled to a predetermined temperature is immediately poured into the optical element molding die 7 provided at the end point of the rolling jig 6 as a spherical optical element material 4a while maintaining the predetermined temperature. You. Then, in the optical element molding die 7, the optical element material 4a is pressed in the direction of the arrow to be molded into a desired optical element 9 such as a collective lens. The pressing condition is that the optical element molding die 7 is heated to 500 to 550 ° C. by the heater 8b.
The molding was performed with a pressing force of 1000 N or more and a pressing time of 10 seconds or more. Then, it was naturally cooled and taken out by a transfer robot (not shown) to obtain an optical element 9 shown in FIG.
At this time, if a plurality of optical element molding dies 7 are prepared and can be easily replaced by a robot, it can be applied to mass production.

According to the optical element manufacturing apparatus of the first embodiment, the glass material before being formed by the mold 7 is uniformly introduced into the mold 7 while being cooled by contact with the air. Therefore, it is possible to obtain the optical element 9 having a desired shape with mirror surfaces on both the upper and lower surfaces without causing problems such as orange peel and cracks. Further, an optical element can be easily obtained without performing steps such as reversal and re-melting on a heat processing jig as in the related art, and the number of steps can be reduced. As a result, downsizing of the device,
The cost can be reduced.

Embodiment 2 FIG. 3 is a sectional view of an optical device manufacturing apparatus according to Embodiment 2 of the present invention. The apparatus for manufacturing an optical element according to the second embodiment is different from the first embodiment in the rolling cooling means. Therefore, the same parts as those in the first embodiment are denoted by the same reference numerals, and duplicate description will be omitted.

[0030] In FIG. 3, are arranged receiving jig 11 having a rolling surface 10 which is curved dished provided drop distance L ₂ from the end surface of the outlet nozzle 3 of the melting crucible 2. Receiving jig 1
1 is rotated in the direction of the arrow by the rotation mechanism 12 and the heater 8
The temperature can be adjusted by c. The drop distance _{L 2} was set to 150 mm. An optical element molding die 7 provided with a temperature adjusting mechanism using a heater 8b is disposed on a side portion of the receiving jig 11.

As the glass material 1, a barium borosilicate glass was used as in Example 1. Receiving jig 1
As a material of No. 1, for example, vitreous carbon was used, and the radius of curvature of the dish-shaped curved surface 10 was 50 mm.

Next, a method for manufacturing an optical element using the apparatus for manufacturing an optical element according to Experimental Example 2 will be described with reference to FIG. In FIG. 3, a solid glass material 1 is put into a molten crucible 2. Then, the molten crucible 2 is heated by the heater 8.
Is heated to 1200 ° C. to melt the glass material 1. The molten glass material 1 has a diameter of about 1 at the tip of the outflow nozzle 3 due to the surface tension of the glass itself.
A spherical glass droplet 4 of ~ 5 mm is formed. The balance between the mass and the surface tension of the glass droplets 4, the glass droplets 4 fall by drop distance L ₂ minutes, rotates in the arrow direction, sequentially on the receiving jig 11 which is heated to 300 to 600 ° C. Fall. The tip of the outflow nozzle 3 is selected above a position between the center and the edge of the receiving jig 11.

In the apparatus configured as above, the dropped glass droplet 4 rolls on the receiving jig 11 for 5 seconds or more.
The surface temperature is cooled to 400-600C. The cooled glass droplet 4 tilts the rolling surface 10 of the receiving jig 11,
The spherical optical element material 4a is immediately put into the optical element molding die 7 provided on the side while maintaining a predetermined temperature.
Then, in the optical element molding die 7, the optical element material 4
a is pressed in the direction of the arrow to be molded into an optical element having a desired shape. The pressing conditions are as follows: the optical element molding die 7 is heated to 500 to 550 ° C. by the heater 8 b, and the pressing force is 100
Molding was performed at 0 N or more and the pressing time was 10 seconds or more. And
After natural cooling, it is taken out by a transfer robot (not shown).
Is obtained.

That is, by dropping the glass droplets 4 onto the rotating heated receiving jig 11 and rolling the glass droplets 4, the glass droplets 4 roll and are uniformly cooled while keeping the spherical shape in all directions. The more spherical optical element material 4a can be put into the optical element molding die 7. Further, the occurrence of orange peel, cracks, and the like, which are likely to occur when partially cooled, can be prevented by using the rotated receiving jig 11 and uniformly cooling the entire surface.

According to the optical element manufacturing apparatus of the second embodiment, it is possible to obtain the optical element 9 having a desired mirror surface on both the upper and lower surfaces without problems such as orange peel and cracking. In addition, since the optical element material 4a having a high sphericity can be supplied to the optical element molding die 7, it is possible to obtain an optical element with high quality and high productivity at low cost.

In the apparatus for manufacturing an optical element of the second embodiment, glassy carbon is used as the material of the receiving jig 11, but a metal having good heat conductivity such as aluminum is used. The same effect can be obtained by placing a thin film such as a graphite film sheet used for the rolling jig. In the embodiment shown in FIG.
Although the example in which the rolling surface (dish-shaped container) is placed horizontally and rotated is illustrated, this is not necessarily limited to the horizontal direction, and is not limited to 0 to 90.
The species may be tilted in the range of ° C. This is because better sphericity can be obtained by rolling on a curved rolling surface as much as possible.

Embodiment 3 FIG. 4 is a sectional view of an optical element manufacturing apparatus according to Embodiment 3 of the present invention. The manufacturing apparatus according to the third embodiment is obtained by adding a heating unit for the optical element material 4a to the apparatus according to the first embodiment, and the same parts as those in the first embodiment are denoted by the same reference numerals, and the overlapping description will be omitted.

[0038] In FIG. 4, the drop distance L ₃ from the end face of the outlet nozzle 3 of the melting crucible 2 is provided, the rolling jig 6 having an inclined surface is disposed at a length of 100 mm, excellent heat resistance thereon The thin film body 5 is placed. Fall distance _{L 3} at this time,
It was set to 150 mm. Then, at the end point of the rolling jig 6,
Second with inclined surface processed with stainless steel porous material
The heating jig 13 was arranged at a length of 100 mm as a rolling jig. The heating jig 13 is provided with a copper tube 14 for supplying a high-temperature gas to be ejected to the inclined surface. At the end point of the heating jig 13, the optical element molding die 7 provided with a temperature adjusting mechanism by the heater 8b was arranged.

The gas supplied from the copper tube 13 and jetted to the inclined surface of the heating jig 13 was N ₂ heated to 500 ° C. or higher.

A method for manufacturing an optical element by the apparatus for manufacturing an optical element according to the third embodiment will be described with reference to FIG. In FIG. 4, a molten glass material 1 is added to a molten crucible 2.
Input. After that, the molten crucible 2 is set to 1 by the heater 8.
The temperature is raised to 200 ° C. to melt the glass material 1. At the end of the outflow nozzle 3, the molten glass material 1 forms a spherical glass droplet 4 due to the surface tension of the glass itself. The balance between the mass and the surface tension of the glass droplets 4, the glass droplets 4 fall by drop distance L ₃ minutes, successively dropped onto the thin film member 5 placed on the rolling jig 6.

The dropped glass droplet 4 rolls on the thin film member 5 and is uniformly cooled until the surface temperature falls to 400 to 600 ° C., thereby forming an optical element material 4 a having a solidified surface. The optical element material 4a moves onto a heating jig 13 made of a stainless porous material disposed at the end point of the rolling jig 6. Since N ₂ supplied from the copper tube 14 and heated to 500 ° C. or more is jetted onto the inclined surface of the heating jig 13, the optical element material 4 a is left floating on the N hot jet. That is, it moves on the heating jig 13 without being in contact with the inclined surface of the heating jig 13. As a result, the optical element material 4a whose surface has been solidified by being once cooled to the glass softening point or lower by the rolling jig 6 is once again heated to near the glass softening point,
The inner surface temperature and the surface temperature of the optical element material 4a become substantially uniform.

Thereafter, the optical element material 4a is
From the end point of 3, a parabola is drawn by the energy of movement and the gravity, and is charged into the optical element molding die 7 while maintaining a predetermined temperature. In the optical element molding die 7, the optical element material 4a is pressed in the direction of the arrow to be molded into an optical element having a desired shape. The pressing condition is as follows.
The molded body was heated to 0 to 550 ° C., the pressing force was 1000 N or more, and the pressing time was 10 seconds or more. Then, the substrate was naturally cooled and taken out by a transfer robot (not shown) to obtain the optical element 9 shown in FIG.

At this time, if a plurality of optical element molding dies 7 are prepared and can be easily replaced by a robot, it can be applied to mass production. In addition, since the temperature of the entire optical element material 4a is uniform, it is possible to completely prevent orange peel, cracks, and the like generated due to a temperature difference when conventionally pressed. Further, the softened glass material 4a is
Since the upper part is moved in a non-contact manner, it is possible to obtain a good optical element 9 without deposits on the surface.

According to the apparatus for manufacturing an optical element of the third embodiment, it is possible to obtain an optical element having a desired shape with mirror surfaces on both upper and lower surfaces without problems such as orange peel and cracks. Also, an optical element can be easily obtained without performing steps such as reversing and re-melting of a heat processing jig and the like. It becomes possible.

In the manufacturing apparatus of the third embodiment, a heating jig using a device that emits a hot jet from the pores of a porous material is used as a heating means for the cooled optical element material.
However, as a heating means, it has high heat resistance even if it is not non-contact, and has low wettability with glass. The same effect can be obtained even if the optical element material 4a is heated by heating.

[0046]

As described above in detail in the embodiments,
According to the method for manufacturing an optical element of the present invention, the temperature of the entire glass droplet is uniformly cooled or raised by the rolling means,
An optical element having a desired shape without orange peel or cracks can be manufactured with high productivity. Further, according to the optical element manufacturing apparatus of the present invention, the entire glass droplet can be cooled or heated while maintaining a spherical state by the rolling means, and the glass droplet can be inverted and re-melted on a conventional heat processing jig. It becomes unnecessary.
As a result, it is possible to reduce the size of the apparatus and the cost of the optical element by reducing the number of manufacturing steps.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical element manufacturing apparatus according to a first embodiment of the present invention.

FIG. 2 is a side view of an optical element manufactured by the manufacturing apparatus according to the first embodiment of the present invention.

FIG. 3 is a sectional view of an optical device manufacturing apparatus according to a second embodiment of the present invention.

FIG. 4 is a sectional view of an optical device manufacturing apparatus according to a third embodiment of the present invention.

FIG. 5 is a sectional view of a conventional optical element manufacturing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass material 2 Melt crucible 3 Outflow nozzle 4 Glass droplet 4a Optical element material 5 Thin film body 6 Rolling jig 7 Optical element molding die 8, 8a, 8b, 8c Heater 9 Optical element 10 Rolling surface 11 Receiving jig 12 Rotating mechanism 13 Heating jig 14 Copper tube

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Kenji Inoue 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (15)

[Claims] A step of melting a glass material with a melting crucible and dropping a glass droplet formed at a tip of an outflow nozzle provided at a lower portion of the melting crucible to form a spherical glass droplet; Rolling the glass droplet while maintaining the spherical shape of the spherical glass droplet, thereby uniformly cooling the surface temperature to a predetermined temperature with a predetermined time temperature curve to produce a spherical optical element material; and A process of immediately charging the optical element material into an optical element molding die and pressing it to form an optical element having a desired shape. 2. The method for manufacturing an optical element according to claim 1, wherein the surface temperature of the dropped spherical glass droplet is rapidly cooled to a temperature between 400 ° C. and 600 ° C. 3. A step of melting a glass material with a melting crucible and dropping a glass droplet formed at the tip of an outflow nozzle provided below the melting crucible to form a spherical glass droplet. While maintaining the spherical shape of the spherical glass droplet,
Cooling the surface temperature to below the softening point of the glass material to form a spherical optical element material; heating the spherical optical element material to near the softening point again; and raising the temperature to near the softening point. A method for manufacturing an optical element, comprising a step of directly charging the optical element material into an optical element molding die and pressing the same to produce an optical element having a desired shape. 4. A molten crucible for melting a glass material, an outflow nozzle provided below the molten crucible to drop the molten glass material into a spherical glass droplet, and a glass droplet dropped from the outflow nozzle. Rolling cooling means for forming a spherical optical element material by cooling while rolling while contacting the slope, and an optical element molding die for molding the optical element material disposed at the end point of the rolling cooling means. Device for manufacturing an optical element. 5. The manufacturing of an optical element according to claim 4, wherein said rolling cooling means is formed of a curved and inclined gutter-shaped rolling jig for receiving said glass droplet. apparatus. 6. The rolling jig is made of a material having at least a slope in contact with the glass droplet having a heat conductivity equal to or higher than that of a cemented carbide or vitreous carbon and having excellent heat dissipation. 6. The semiconductor device according to claim 5, wherein:
An apparatus for manufacturing the optical element described in the above. 7. The apparatus for manufacturing an optical element according to claim 5, wherein at least a slope of the rolling jig that comes into contact with the glass droplet is formed of a material having poor wettability with glass. 8. The apparatus for manufacturing an optical element according to claim 4, wherein a temperature adjusting mechanism capable of heating the temperature to 50 ° C. to 600 ° C. is provided at least in a peripheral portion of the optical element mold. 9. The apparatus for manufacturing an optical element according to claim 4, wherein said rolling cooling means is formed by a dish-shaped receiving jig capable of adjusting the temperature for receiving said glass droplets. 10. A material having at least a surface having a heat conductivity equal to or higher than that of a cemented carbide or vitreous carbon and having excellent heat dissipation properties, wherein at least a surface of the dish-shaped receiving jig which comes into contact with the glass droplets. The apparatus for manufacturing an optical element according to claim 9, wherein: 11. The apparatus for manufacturing an optical element according to claim 9, wherein the dish-shaped receiving jig is configured to be rotatable in a horizontal direction and to be capable of adjusting a temperature. 12. The rolling cooling means includes a gutter-shaped first rolling jig having a curved and inclined shape for receiving the glass droplet.
5. The optical element manufacturing apparatus according to claim 4, further comprising a second rolling jig having a temperature adjusting mechanism disposed at an end point of the first rolling jig. 6. 13. The apparatus for manufacturing an optical element according to claim 12, wherein the second rolling jig having the temperature adjusting mechanism is capable of adjusting the heating to near a softening point of the glass material. 14. A first rolling jig having a curved and inclined shape for receiving the glass droplets, rolling and cooling the glass droplets to form a spherical optical element material, and A heating jig having a curvature and an inclination made of a porous material capable of ejecting a heated gas is provided on at least a surface to which the optical element material is moved, which is disposed at an end point of the first rolling jig. An apparatus for manufacturing an optical element according to claim 4. 15. The heating jig made of a porous material,
15. The apparatus for manufacturing an optical element according to claim 14, wherein the apparatus is formed of a material having heat resistance higher than a softening point of the glass material.