Glass manufacturing device, glass, optical system, optical device, and manufacturing method of glass

Abstract

To provide a glass manufacturing device capable of acquiring optical glass with predetermined thickness, and to provide a manufacturing method of glass.SOLUTION: A glass manufacturing device which manufactures glass via a step of lowering a temperature of a molten liquid of a glass raw material includes: a heating part for heating a glass raw material supported in a non-contact manner; a heating control part for controlling the heating amount of the glass raw material by the heating part; and a molding part 30 for molding the glass raw material in a molten liquid state in which the temperature has changed based on the control of the heating amount by the heating control part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a glass manufacturing apparatus, glass, an optical system, an optical device, and a glass manufacturing method. [Background technology]

[0002] For example, Patent Document 1 discloses a method for manufacturing optical glass using a laser levitation furnace. In such a laser levitation furnace, it is required to stably levitate the glass sample with a levitation gas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-196236 Summary of the Invention

[0004] An aspect of the present invention is, for example, a glass manufacturing apparatus for manufacturing glass through a process of lowering the temperature of glass frits supported in a non-contact manner, the apparatus comprising: a heating unit for heating the glass frits; a heating control unit for controlling the amount of heat applied to the glass frits by the heating unit; and a forming unit for forming the glass frits in a molten state whose temperature has been changed based on the control of the amount of heat applied by the heating control unit.

[0005] Another aspect of the present invention is glass produced using the above-described glass production apparatus.

[0006] Another aspect of the present invention is an optical system using the above-mentioned glass.

[0007] Another aspect of the present invention is an optical device using the above-described optical system.

[0008] Another aspect of the present invention is a method for producing glass, which comprises producing glass using the above-described glass production apparatus.

[0009] Another aspect of the present invention is a glass manufacturing method for manufacturing glass through a step of lowering the temperature of glass frits supported in a non-contact manner, the method comprising: a melting step of heating and melting the glass frits by a heating unit; a heating control step of controlling the amount of heat of the glass frits by the heating unit; and a shaping step of shaping the glass frits in a molten state whose temperature has been changed by controlling the amount of heat by the heating control step.

[0010] Another aspect of the present invention is a glass manufacturing apparatus for manufacturing glass by cooling glass raw materials, the apparatus comprising: a support member for supporting the glass raw material in a molten state in a non-contact manner; and a stage to which the support member is fixed, and the support member is removable from the stage. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram of a glass manufacturing apparatus equipped with a levitation furnace including a holding member according to one embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram (cross-sectional view) showing a state in which the sample suspended above the support in FIG. 1 is heated. [Figure 3] Figure 3 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment. Figure 3(A) is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment, Figure 3(B) is a view (part 1) of the shaping member 31 seen from the support member 12 side, and Figure 3(C) is a view (part 2) of the shaping member 31 seen from the support member 12 side. [Figure 4] FIG. 4 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the second embodiment. [Figure 5] FIG. 5 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in a modified example of the second embodiment. [Figure 6] FIG. 6 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the third embodiment. [Figure 7] FIG. 7 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fourth embodiment. [Figure 8]Figure 8 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment. Figure 8(A) is a first schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment, and Figure 8(B) is a second schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment. [Figure 9] Fig. 9 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the sixth embodiment. Fig. 9(A) is a schematic diagram No. 1 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the sixth embodiment, Fig. 9(B) is a modified example of the shaping member 38, and Fig. 9(C) is a schematic diagram No. 3 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the sixth embodiment. Fig. 9(D) is a modified example of the shaping method of sample U using shaping member 383. [Figure 10] Fig. 10 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the seventh embodiment. Fig. 10(A) is a schematic diagram (cross-sectional view) showing an example of a formed member in the seventh embodiment, and Fig. 10(B) is a schematic diagram (cross-sectional view) showing a modified example of the formed member in the seventh embodiment. [Figure 11] Fig. 11 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the eighth embodiment. Fig. 11(A) is a schematic diagram (cross-sectional view) showing an example of the forming part in the eighth embodiment, and Fig. 11(B) is a schematic diagram (cross-sectional view) showing a modified example of the forming part in the eighth embodiment. [Figure 12] Fig. 12 is a diagram for explaining a levitation furnace in the ninth embodiment. Fig. 12(A) is a schematic diagram (cross-sectional view) showing an example of a forming unit in the ninth embodiment, and Fig. 12(B) is a schematic diagram (cross-sectional view) for explaining forming using the forming unit in the ninth embodiment. [Figure 13] Figure 13 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the tenth embodiment. Figure 13(A) is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the tenth embodiment, and Figure 13(B) is a schematic diagram (cross-sectional view) showing a modified example of the levitation furnace in the tenth embodiment. [Figure 14]14A and 14B are diagrams for explaining heating control of the sample U in the first to tenth embodiments. Fig. 14A is a diagram (part 1) showing an example of a standard heating amount, Fig. 14B is a diagram (part 2) showing an example of a standard heating amount, and Fig. 14C is a diagram showing an example of a state in which the heating amount is reduced. [Figure 15] FIG. 15 is a diagram showing the measurement results of the samples obtained in Examples 1 and 2. [Figure 16] FIG. 16 is a diagram showing the measurement results of the sample U obtained as a result of Examples 3 to 5. [Figure 17] Fig. 17 shows the measurement results of sample U1 and sample U2 obtained as a result of Example 6. Fig. 17(A) shows the measurement results of sample U1, and Fig. 17(B) shows the measurement results of sample U2. [Figure 18] FIG. 18 is a perspective view of an example in which the optical device according to each embodiment is used as an imaging device. [Figure 19] FIG. 19 is a front view of another example in which the optical device according to each embodiment is used as an imaging device. [Figure 20] FIG. 20 is a rear view of another example in which the optical device according to each embodiment is used as an imaging device. [Figure 21] FIG. 21 is a block diagram showing an example in which the optical device according to each embodiment is a multiphoton microscope. [Figure 22] FIG. 22 is a schematic diagram showing an example of a cemented lens according to each embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described. The present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content.

[0013] In the drawings, the same elements are denoted by the same reference numerals, and redundant explanations will be omitted. Furthermore, unless otherwise specified, the positional relationships, such as up, down, left, and right, are based on the positional relationships shown in the drawings. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0014] Furthermore, terms with "abbreviation" attached indicate the meaning of the term excluding "abbreviation" within the scope of common general technical knowledge of a person skilled in the art, and also include the meaning itself excluding "abbreviation." The same is true vice versa. For example, the term "circle" does not have "abbreviation" attached, but naturally includes the meaning of "approximately circle" as long as it does not contradict the gist of the invention.

[0015] Furthermore, the "cross section" in "cross-sectional view" or "cross-sectional view" refers to a cross section passing through the center or center of gravity of the concave surface R of the support member 12 described below when the support member 12 is placed on a horizontal plane perpendicular to the direction of gravity with the concave surface R facing up, and is a cross section perpendicular to the horizontal plane.

[0016] <Outline of Glass Manufacturing Equipment 10>

[0017] Fig. 1 is a schematic diagram of a glass manufacturing apparatus 10 equipped with a levitation furnace including a levitation unit (support unit) 21 according to this embodiment, and Fig. 2 is a schematic diagram (cross-sectional view) showing a state in which a sample U levitated on the levitation unit 21 in Fig. 1 is being heated. Note that levitating the sample U by the levitation unit 21 is also referred to as supporting the sample U in a non-contact manner.

[0018] As shown in FIG. 1, glass manufacturing apparatus 10 is an optical glass manufacturing apparatus equipped with a gas jet levitation furnace. Glass manufacturing apparatus 10 produces glass by heating and melting glass raw materials while levitating them using gas. Glass manufacturing apparatus 10 includes a levitation furnace including a support member 12 that blows gas onto a sample U containing glass raw materials to levitate it; a laser light source 13 that irradiates the levitated sample U with laser light L; a radiation thermometer 16 that measures the temperature of the levitated sample U; a computer 17 that has a control unit 22 (not shown) that controls the output of laser light source 13, support member 12, and a forming unit 30 (described later) based on temperature information from radiation thermometer 16; and a gas flow regulator 20 that adjusts the flow rate of gas supplied to support member 12. Support member 12 and gas flow regulator 20 are included in a levitation unit 21 that levitates sample U.

[0019] In the glass manufacturing apparatus 10, a sample U floating above a support member 12 arranged on a stage 11 is heated in a non-contact manner by irradiation with a laser beam L. In other words, a laser light source 13 that irradiates the laser beam L functions as a heating unit. As a result, the sample U melts and becomes a molten liquid having a substantially spherical or ellipsoidal shape due to its own surface tension, and floats in that state.

[0020] Non-contact heating of the sample U is performed by irradiating the sample U with laser light L emitted from a laser light source 13 via mirrors 14 and 15. The temperature of the sample U heated by irradiation with the laser light L is monitored by a radiation thermometer 16. Based on the temperature information of the sample U monitored by the radiation thermometer 16, the output of the laser light source 13 is controlled by a computer 17. In addition, the state of the sample U is imaged by a CCD camera 18, and the image is output to a monitor 19. The laser light source 13 is not particularly limited, and examples thereof include a carbon dioxide laser, a semiconductor laser, a fiber laser, and a YAG laser.

[0021] The flow rate of the gas fed into the support member 12 is controlled by a gas flow regulator 20. The type of gas is not particularly limited, and any known gas can be used as appropriate. Specific examples include oxygen, carbon dioxide, nitrogen, argon, and air. The shape of the nozzle (not shown) connected to the support member 12 is not particularly limited, and any known method can be used as appropriate.

[0022] After the stably levitated sample U is heated in a non-contact manner, the laser light L is shut off, whereby the melt (sample U) is cooled and solidified, yielding optical glass.

[0023] In this embodiment, external pressure is applied to the molten sample U to form it into a desired thickness and size. The sample U is then cooled and solidified. The optical glass obtained in this manner can be processed into a desired shape as needed, and polished or otherwise processed to form a desired optical element.

[0024] 2, the support member 12 has a first surface W1 having a concave surface R facing the sample U, and a second surface W2 opposite the first surface W1, which is a gas introduction surface. The second surface W2 has an inlet through which gas is introduced, and the concave surface R of the first surface W1 has an outlet through which the gas is ejected. The gas introduced from the inlet is ejected from the outlet, causing the sample U to levitate.

[0025] The support member 12 may be any member that can levitate the sample U, and the shape and structure are not limited to the example shown in Fig. 2. For example, the support member 12 may be formed of a porous member, and the sample U may be levitated by injecting gas taken in from the second surface W2 from the first surface W1. Additionally, the shape of the support member 12 is not limited to the example shown in this figure, and may be modified as appropriate.

[0026] Furthermore, for example, the support member 12 may levitate the sample U using static electricity. In this case, the glass manufacturing apparatus 10 does not have the gas flow regulator 20, but instead has an electrostatic device (not shown) that charges the sample U. The support member 12 can levitate the sample U, for example, placed between one to multiple pairs of electrodes that constitute the electrostatic device, using static electricity. Note that the method by which the support member 12 levitates the sample U is not limited to the above example, and may be, for example, an electromagnetic method, an acoustic method, a magnetic method, or the like.

[0027] First Embodiment Figure 3 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment. Figure 3(A) is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment, Figure 3(B) is a view (part 1) of the shaping member 31 seen from the support member 12 side, and Figure 3(C) is a view (part 2) of the shaping member 31 seen from the support member 12 side.

[0028] In the conventional glass manufacturing apparatus 10, when optical glass is manufactured using a levitation furnace, the sample U is melted by laser irradiation and then solidified by cooling to obtain the optical glass. During this process, the thickness of the sample U is limited due to the relationship between the surface tension and gravity acting on the sample U.

[0029] The glass manufacturing apparatus 10 of this embodiment makes it possible to obtain optical glass of a desired thickness by shaping the molten sample U during the temperature drop process.

[0030] Glass manufacturing apparatus 10 in the first embodiment includes levitation unit 21 including support member 12 and gas flow regulator 20, stage 11, laser light source 13, mirrors 14 and 15, radiation thermometer 16, computer 17 having control unit 22, CCD camera 18, monitor 19, and also includes shaping unit 30 that is levitated by levitation unit 21 and shapes a molten glass raw material liquid.

[0031] The shaping unit 30 has shaping members 31 (31a and 31b), which are pressed against the molten glass as shown in FIG. 3(A) to form the sample U. The shaping members 31 deform the shape of the melt of the sample U. As an example, there are multiple shaping members 31, each of which is a claw-like member that is driven by a motor in a direction parallel to the horizontal direction (for example, the +X direction and the -X direction). Each of the shaping members 31 is arranged to surround the sample U, and by being driven to open and close freely, the sample U is clamped from multiple different directions. That is, the shaping unit 30 forms the sample U by pressing the multiple shaping members 31 against the melt of the sample U from multiple directions toward the center.

[0032] Although the material of the forming member 31 is not particularly limited, it is preferable that at least a part or all of the forming member 31 contains stainless steel (SUS), aluminum alloy, quartz, or carbon. These materials have excellent thermal shock resistance and abrasion resistance even at high temperatures, and also have moderately suppressed wettability with glass, thereby suppressing the formation of crystallization points in the molten glass. Furthermore, the melting point of the material of the portion of the forming member 31 that comes into contact with the molten glass is preferably 500°C or higher, since it is desirable that the material not deform even at high temperatures.

[0033] As an example, the shaping members 31 are two pairs of claw-shaped members facing each other, as shown in FIG. 3(B). FIG. 3(B) is a view of the shaping members 31 and the specimen U as seen from below (the support member 12 side). The shaping members 31 (31c-f) are arranged to surround the specimen U. In this embodiment, the surface of the shaping members 31 that comes into contact with the specimen U is arc-shaped. Each pair of the shaping members 31 (31c-31d) moves in the +X direction or the -X direction, while the other pair of the shaping members (31e-31f) moves in the +Y direction or the -Y direction. In other words, the shaping members 31 can be opened and closed to sandwich and shape the specimen U from four directions (+X direction, -X direction, +Y direction, and -Y direction).

[0034] The shaping member 31 shown in FIG. 3(B) can increase the length of the sample U in the Z-axis direction while changing the shape of the sample U. The arrangement and number of shaping members 31 are not limited to these, but can be four or more. In this case, the shaping unit 30 presses the shaping members 31 against the glass melt from four or more directions to shape it. The shape of the shaping member 31 that comes into contact with the sample U is designed appropriately.

[0035] A specific example is shown below. FIG. 3(C) is a view of the forming member 31 and the sample U viewed from below (the support member 12 side). The surface of the forming member 31 that comes into contact with the sample U may be flat. By using a forming member such as that shown in FIG. 3(C), the length of the sample U in the Z-axis direction can be increased while changing the shape of the sample U. Alternatively, the shape of the sample U can be shaped to suit the application by changing the number of forming members 31 or the shape of the surface that comes into contact with the sample U. The forming member 31 can reduce the effort required to process the vitrified sample U. Furthermore, to prevent damage to the sample U due to the temperature difference between the forming member 31 and the sample U, the forming member 31 may be preheated before shaping.

[0036] After the laser irradiation by the laser light source 13 has stopped, the forming unit 30 lowers the multiple forming members 31 in an open state. At this time, it is preferable that the forming unit 30 positions the sample U near the center of the multiple open forming members 31. Thereafter, the forming unit 30 drives the multiple forming members 31 in a closing direction (for example, the +X direction and the -X direction) so as to sandwich the sample U, and brings the forming members 31 into contact with the sample U. The forming unit 30 increases the thickness of the sample U by further pressurizing the forming members 31 in the closing direction. Thereafter, the sample U is removed from the forming members 31, thereby obtaining optical glass of the desired thickness.

[0037] Furthermore, the sample U is molded by the molding member 31 up to a temperature at which the sample U no longer deforms. When the temperature of the sample U becomes lower than the temperature at which the sample U no longer deforms, the sample U may be removed from the molding member 31 and cooled. The temperature at which the sample U no longer deforms is preferably a temperature equal to or lower than the glass transition point (glass transition temperature) of the sample U.

[0038] The molding of the sample U by the molding unit 30 is preferably performed at a temperature below the deformation point of the sample U, and more preferably below the deformation point and above the glass transition point. If molding is performed using the molding member 31 at a temperature above the deformation point, contact of the molding member 31 with the sample U may cause crystallization due to excessive wettability, potentially resulting in devitrification. Sample U between the glass transition point and the deformation point has a viscosity suitable for molding by pressure, and excessive wettability to the molding member 31 is suppressed, allowing optical glass of the desired thickness and size to be obtained more efficiently.

[0039] It is preferable to use the control unit 22 to set the timing for forming the sample U by the forming unit 30. Before forming the sample U, the control unit 22 acquires information on the physical properties of the sample U, which are predetermined characteristics of the sample U. Specifically, this information is the glass transition point and yield point of the sample U. Therefore, the control unit 22 controls the forming unit 30 so that the sample U can be formed at the above-mentioned preferred temperature. It is to be noted that the physical properties are not limited to these, and also include physical properties required when the forming unit 30 forms the glass melt.

[0040] The control unit 22 monitors the temperature state of the molten glass after the laser irradiation is stopped using the radiation thermometer 16, and controls the forming unit 30 to form the sample U so that the temperature at the time of forming the sample U is above the glass transition point and below the deformation point.

[0041] Furthermore, the control unit 22 may have a calculation unit 23 that calculates the timing to control the molding unit 30. The calculation unit 23 calculates the timing to mold the sample U by the molding unit 30 based on information on the yield point and glass transition point of the sample U and the weight of the raw material of the sample U. The reason for using information on the weight of the raw material of the sample U is that the cooling rate after the laser irradiation is stopped varies depending on the weight of the sample U, so more preferable timing can be calculated by also using information on the weight of the raw material of the sample U. The information used by the calculation unit 23 may be not only the weight of the raw material of the sample U but also the size of the sample U (volume, surface area, etc.).

[0042] In this embodiment, the sample U is continuously shaped from its melting, but a sample U that has already been vitrified may also be used as the shaping target. In this case, the sample U suspended by the support member 12 is heated to a temperature equal to or higher than the liquidus temperature of the glass of the sample U. Thereafter, the laser irradiation is stopped again, and the sample U is shaped by the shaping unit 30 at a temperature equal to or lower than the yield point and higher than the glass transition point.

[0043] <Second embodiment> 4 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the second embodiment. Differences from the first embodiment will be described below. The shaping unit 30 in the second embodiment includes a suction unit 32 instead of the shaping member 31. The suction unit 32 is a hollow cylindrical member connected to a suction device (not shown) and sucks the sample U by reducing the pressure inside. That is, the glass manufacturing apparatus 10 in the second embodiment sucks and shapes molten glass.

[0044] The suction portion 32 has a tapered cross section, with the inside of the tip gradually narrowing as it progresses inward. The tapered shape allows the suctioned glass to gather in the center, increasing the thickness. As with the forming member 31 in the first embodiment, it is preferable that at least a part or all of the suction portion 32 contains stainless steel (SUS), aluminum alloy, quartz, or carbon.

[0045] After the laser irradiation by the laser light source 13 has stopped, the forming unit 30 forms the sample U using the suction unit 32, which is positioned so that the sample U can be sucked in. The suction unit 32 is preferably positioned directly above the sample U, with its center coinciding with the center of the sample U. The forming unit 30 reduces the pressure inside the suction unit 32 and sucks in the sample U. During suction, the outer edge of the sample U comes into contact with the lower end or inner wall of the suction unit 32, and the central portion of the sample U is sucked upward, increasing the thickness of the sample U in the Z-axis direction. The sample U is then removed from the forming unit 30 and cooled, thereby obtaining optical glass of the desired thickness.

[0046] <Modification of the second embodiment> 5 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in a modified example of the second embodiment. Differences from the second embodiment will be described below. The shaping unit 30 in this modified example has a shaping member 33 in addition to a suction unit 32. The shaping member 33 shapes a sample U, which is molten glass.

[0047] The shaping member 33 functions as a mold for shaping the sample U. The shaping member 33 is arranged in the direction in which the suction unit 32 suctions the sample U, and adjusts the shape of the sample U by coming into contact with the sample U sucked by the suction unit 32. As an example, in the shaping unit 30, the suction unit 32 is provided so as to surround the shaping member 33 with respect to a plane perpendicular to the direction of gravity.

[0048] After the laser irradiation by the laser light source 13 has stopped, the shaping unit 30 shapes the sample U using the suction unit 32, which is positioned so that the suction unit 32 can suck the sample U. The suction unit 32 is preferably positioned so that its center coincides with the center of the sample U and is directly above the sample U. As a result, the shaping member 33 is positioned directly above the sample U.

[0049] The forming unit 30 reduces the pressure inside the suction unit 32 and sucks in the sample U. The upper part of the sucked sample U comes into contact with the forming member 33. As a result, the sample U is pressed against the forming member 33, and the upper part of the sample U is shaped to match the shape of the forming member 33. If the support member 12 continues to supply gas to the sample U at this time, the sample U is pressurized from above by the forming member 33 and from below by the gas. In other words, the sample U is molded while sandwiched between the gas from the support member 12 and the forming member 33. The sample U is then cooled to obtain optical glass of the desired thickness and shape.

[0050] Note that the shaping unit 30 may adjust the shape of the sample U by moving the shaping member 33 downward during suction by the suction unit 32. Even in this case, if the support member 12 continues to supply gas to the sample U, the sample U will be sandwiched between the gas from the support member 12 and the shaping member 33 and shaped. This not only shapes the upper part of the sample U into the desired shape, but also increases the diameter of the sample U to a desired size.

[0051] Alternatively, the forming unit 30 may press the forming member 33 against the sample U from above and bring the lower part of the sample U into contact with the concave surface R of the support member 12, thereby sandwiching and forming the molten glass between the support member 12 and the forming member 33. The shapes of the surfaces of the suction unit 32 and the forming member 33 that come into contact with the sample U may be designed as appropriate.

[0052] <Third embodiment> 6 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the third embodiment. The differences from the first embodiment will be described below. The forming unit 30 in this embodiment forms the sample U by blowing gas onto the sample U.

[0053] As in the other embodiments, in this embodiment, gas is sprayed upward onto the sample U from nozzles 24 (not shown) provided in the flotation unit 21, thereby maintaining the sample U in a floating state. The forming unit 30 has multiple nozzles 34 (34a-34b) that spray gas onto the sample U from lateral directions (+X direction, -X direction). Each of the multiple nozzles 34 sprays gas toward the center of the sample U from a different direction. This causes the sample U to be pressurized from the lateral direction toward the center, increasing its thickness. The number of nozzles 34 is not limited to two, but is preferably four or more. Furthermore, it is preferable that the nozzles 34 are arranged so as to surround the sample U, which allows for uniform molding of the sample U. Furthermore, it is preferable that the nozzles 34 are spaced approximately equally apart.

[0054] In the example shown in FIG. 6, the forming unit 30 is a plurality of holes drilled in the support member 12, and each hole functions as a nozzle 34. Alternatively, the forming unit 30 may be provided above the support member 12 as a separate mechanism from the support member 12 that levitates the sample U. When the laser irradiation from the laser light source 13 is stopped, the sample U is maintained in a levitated state by the upward gas injection from the support member 12. Thereafter, the forming unit 30 injects gas laterally toward the sample U, applying pressure from the periphery toward the center of the sample U. The sample U is then cooled to obtain optical glass of the desired thickness.

[0055] <Fourth embodiment> FIG. 7 is a schematic diagram (cross-sectional view) showing an example of the vicinity of a levitation furnace in the fourth embodiment. Differences from the first embodiment will be described below. The levitation unit 21 in this embodiment has a support member that levitates the glass melt and a dividing unit 37 that divides the support member. The shaping unit 30 in this embodiment has a plurality of shaping members 36 (36a, 36b).

[0056] The support member 12 can be divided into multiple pieces in a plane perpendicular to gravity. The dividing unit 37 divides the support member 12 into multiple pieces. For example, the dividing unit 37 divides the support member 12 by pulling each of the pieces constituting the support member 12 outward.

[0057] The forming members 36 (36a and 36b) are molds that can be formed by applying pressure to the heated sample U, and it is preferable that at least a part or all of the members contain stainless steel (SUS), aluminum alloy, quartz, or carbon. The forming members 36 are a plurality of members arranged around the sample U, and apply pressure to the sample U laterally and from different directions toward the center of the sample U.

[0058] The multiple shaping members 36 are located below the support member 12, and before the support member 12 is divided, the multiple shaping members 36 are located at positions separated from each other. After the laser irradiation by the laser light source 13 is stopped, the dividing unit 37 divides the support member 12, with the sample U levitated, in a plane perpendicular to gravity. By dividing the support member 12, the support member 12 releases its hold on the sample U, and the sample U falls.

[0059] Each forming member 36 moves toward the center of the sample U to receive the falling sample U and hold it from the side. Then, the forming members 36 move further toward the center of the sample U, increasing the thickness of the sample U. In other words, the forming unit 30 presses the forming members 36 against the falling sample U from at least two directions (+X direction, -X direction), thereby forming the sample U. Then, the sample U is removed from the forming members 36, and the sample U is cooled, thereby obtaining optical glass of the desired thickness.

[0060] In this embodiment, the forming member 36 may be a container with upright walls. In this case, the forming member 36 applies pressure to the periphery of the sample U by moving the wall toward the center of the sample U, thereby increasing the thickness of the sample U. In other words, the forming unit 30 can form the sample U by placing the sample U that has fallen due to the separation of the holding member into the forming member 36. The shape of the surface of the forming member 36 that comes into contact with the sample U can be designed as appropriate.

[0061] <Fifth embodiment> FIG. 8 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment. FIG. 8(A) is a first schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment, and FIG. 8(B) is a second schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment. Differences from the first embodiment will be explained below. The forming unit 30 in this embodiment has one or more forming members 35 (35a-35b). The forming unit 30 forms a sample U that has been heated, cooled to room temperature, and then reheated using the forming members 35.

[0062] 8(A), in glass manufacturing apparatus 10, sample U is suspended above support member 12. At this time, laser light L is emitted from laser light source 13 (not shown) toward sample U, thereby heating sample U. Thereafter, sample U is cooled to room temperature, and optical glass is obtained.

[0063] Next, the molding unit 30 reheats the sample U. Reheating may be performed by holding the sample U with the support member 12 and emitting laser light L, or by using another heating device. The reheated sample U is placed in a position where it can be molded by the molding member 35. The sample U placed on the molding member 35 is molded at a temperature above the glass transition point and below the yield point. In other words, the sample U is reheated so that it is above the glass transition point and below the yield point during molding.

[0064] The forming member 35 is a mold that can be formed by applying pressure to the heated sample U. As with the forming member 33 in the above-described embodiment, it is preferable that at least a part or all of the forming member 35 contains stainless steel (SUS), an aluminum alloy, quartz, or carbon.

[0065] In the example shown in FIG. 8(B), the forming members 35 are a plurality of members arranged around the sample U, which apply pressure to the sample U from different lateral directions toward the center of the sample U. After applying pressure, the sample U is cooled again to obtain optical glass of the desired thickness. Note that the configuration of the forming members is not limited to this example. For example, similar to the forming member 31 of the first embodiment, the forming members may be a plurality of claw-shaped members, or a container with upright walls into which the heated viscous sample U is inserted and deformed.

[0066] According to this embodiment, the sample U can be molded after levitation, improving efficiency. Furthermore, by reheating the sample U to a temperature above the glass transition point and below the yield point, optical glass of a desired thickness can be obtained while suppressing devitrification. The shape of the surface of the molding member 35 that comes into contact with the sample U can be designed as appropriate.

[0067] Sixth Embodiment In the first to fifth embodiments described above, the objective was to increase the thickness of the sample U in the vertical direction (Z direction), but the diameter of the sample U in the horizontal direction (X direction) may also be increased. FIG. 9 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the sixth embodiment. FIG. 9(A) is a schematic diagram 1 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the sixth embodiment, FIG. 9(B) is a modified example of the shaping member 381, and FIG. 9(C) is a schematic diagram 2 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the sixth embodiment. FIG. 9(D) is a modified example of the shaping method of the sample U using the shaping member 383.

[0068] In the example shown in FIG. 9(A), the forming member 381 contacts the sample U suspended by the support member 12 from the direction of gravity (-Z direction), sandwiching the sample U between the support member 12 and the forming member 381. In other words, the forming member 381 applies pressure from above the sample U to form it. This increases the horizontal diameter of the sample U. The forming of the sample U by the forming member 381 is preferably performed at a temperature below the deformation point of the sample U, and more preferably at a temperature below the deformation point and above the glass transition point. Note that during forming, the suspending of the sample U by the support member 12 may be stopped or may remain suspended. At this time, the shape of the tip of the forming member 381 on the sample U side may be any desired shape. For example, the forming member 381 may have a lens shape like the forming member 382 in FIG. 9(B) or an aspherical lens shape (not shown).

[0069] An example shown in FIG. 9(C) will be described. The support member 12 is the same as in the fourth embodiment, so its description will be omitted. Initially, the sample U is floating on the support member 12. When the support member 12 is divided by the dividing section 37, the sample U falls in the direction of gravity. The dropped sample U is received by the forming member 383. The sample U is molded to fit the shape of the forming member 383. In other words, the sample U may be molded to fit the shape of the forming member 383 by its own weight. Note that, as shown in FIG. 9(D), in addition to the weight of the sample U, pressure may be applied from above the sample U on the forming member 383 using the forming member 381.

[0070] The sample U is preferably formed using the forming members 381 to 383 at a temperature equal to or lower than the yield point, and more preferably at a temperature equal to or lower than the yield point and equal to or higher than the glass transition point.

[0071] Seventh Embodiment The glass manufacturing apparatus 10 of the seventh embodiment can increase the diameter of the sample U in the horizontal direction (X direction) as in the sixth embodiment. Fig. 10 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the seventh embodiment. Fig. 10(A) is a schematic diagram (cross-sectional view) showing an example of a shaping member in the seventh embodiment, and Fig. 10(B) is a schematic diagram (cross-sectional view) showing a modified example of the shaping member in the seventh embodiment.

[0072] In the example shown in FIG. 10(A), the forming unit 30 has a forming member 384. Similar to the forming members 381 and 382 shown in FIG. 9, the forming unit 30 brings the forming member 384 into contact with the sample U in a molten state suspended by the support member 12 from the direction of gravity (-Z direction), and sandwiches the sample U between the support member 12 and the forming member 384. That is, the forming member 384 is pressed against the sample U in a molten state from above to form it. Note that the suspension of the sample U may be stopped before the forming member 384 comes into contact with the sample U. That is, the forming member 384 may be brought into contact with the sample U that is directly placed on the support member 12 and supported in contact with it.

[0073] 10(A) has a convex shape at the center of the tip on the sample U side. As a result of molding the molding member 384, the top of the sample U has a concave shape at the center, with the shape of the molding member 384 transferred to it, and the bottom has a shape transferred to it of the support member 12. Note that the support member 12 can have any desired shape.

[0074] The shaping member 385 shown in FIG. 10(B) has a hole H. The hole H is a through-hole that penetrates from the surface of the shaping member 385 at the tip end side on the specimen U side to the other surface of the shaping member 385. If an air pocket exists at the contact surface between the shaping member 385 and the specimen U, it may have an unintended effect on the shape of the specimen U. The hole H prevents the air pocket from occurring at the contact surface between the shaping member 385 and the specimen U.

[0075] The laser light L emitted from the laser light source 13 may pass through the hole H and be irradiated onto the sample U. The forming member 385 may start forming the sample U after heating by irradiation with the laser light L is completed, or may start forming during heating.

[0076] Eighth Embodiment In the first to seventh embodiments described above, one of the objectives is to increase the thickness of the sample U in the vertical direction (Z direction) or the diameter of the sample U in the horizontal direction (X direction or Y direction). In the eighth embodiment, the sample U can be formed into a desired shape. FIG. 11 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the eighth embodiment. FIG. 11(A) is a schematic diagram (cross-sectional view) showing an example of the forming section in the eighth embodiment, and FIG. 11(B) is a schematic diagram (cross-sectional view) showing a modified example of the forming section in the eighth embodiment.

[0077] The forming unit 30 shown in FIG. 11(A) includes a forming member 386 and an auxiliary member 387. Similar to the forming members 381 and 382 shown in FIG. 9 and the forming members 384 and 385 shown in FIG. 10, the forming unit 30 applies pressure to the sample U from above by moving the forming member 386 in the direction of gravity (-Z direction). The auxiliary member 387 is a member arranged to surround the sample U in the horizontal direction. The auxiliary member 387 is a hollow cylinder that surrounds the entire circumference of the sample U. Note that the auxiliary member 387 may be a member with multiple claws, like the forming member 31 shown in FIG. 3. The shape of the tip of the forming member 386 on the sample U side may be any desired shape.

[0078] When the shaping member 386 descends and applies pressure from above to the molten sample U, the diameter of the sample U increases and comes into contact with the auxiliary member 387. As a result, the diameter of the sample U is restricted by the shape of the auxiliary member 387. In other words, the auxiliary member 387 functions as a guide that determines the horizontal size and shape of the sample U. Therefore, the shaping member 386 and the auxiliary member 387 can shape the sample U into a desired shape.

[0079] The forming unit 30 shown in FIG. 11B includes a first forming member 388 and a second forming member 389. Similar to the forming member 386 in FIG. 11A, the forming unit 30 applies pressure to the sample U from above by moving the first forming member 388 in the gravity direction (-Z direction). Similar to the forming member 31 shown in FIG. 3, the second forming member 389 is a plurality of claw-shaped members that move in a direction parallel to the horizontal direction. The claws are arranged to surround the sample U and clamp the sample U from multiple different directions. That is, the forming unit 30 presses the first forming member 388 against the molten sample U from above, and then drives the second forming member 389 within a predetermined plane intersecting the gravity direction to press the sample U against the molten sample U, thereby forming the sample U. Therefore, by using the forming unit 30 of this embodiment, the sample U can be formed into a desired shape.

[0080] <Ninth embodiment> The glass manufacturing apparatus 10 in the ninth embodiment uses a forming member 390 of a predetermined shape to form a sample U into a desired shape. Fig. 12 is a diagram for explaining a levitation furnace in the ninth embodiment. Fig. 12(A) is a schematic diagram (cross-sectional view) showing an example of a forming unit in the ninth embodiment, and Fig. 12(B) is a schematic diagram (cross-sectional view) for explaining forming using the forming unit in the ninth embodiment.

[0081] The shaping unit 30 includes a plurality of shaping members 390. In a cross section taken along the direction of gravity, each shaping member 390 has an L-shape with its lower portion protruding toward the center of the sample U. Similar to the shaping member 31 shown in FIG. 3, each shaping member 390 is a plurality of claw-like members that are driven in a direction parallel to the horizontal direction, are arranged to surround the sample U, and clamp the sample U from a plurality of different directions.

[0082] 12(B) is a cross-sectional view in the gravity direction of the sample U molded by the molding member 390 and the lens T formed using the sample U. By applying pressure to the sample U using the molding member 390, the thickness of the sample U increases and the lower portion U of the sample U also increases. B The diameter of the upper part U AAs shown in this figure, the cross section in the direction of gravity is approximately fan-shaped, and the lower part U B The diameter of the upper part U A When a lens T having a diameter smaller than that of the lens T is desired, the sample U can be formed into a shape closer to that of the lens T by using the forming member 390 according to this embodiment.

[0083] In this embodiment, since the sample U is heated while being levitated, it is desirable to more effectively utilize the volume of the sample U. By using the molding member 390 of this embodiment, the sample U can be formed into a shape that is close to the shape of the lens T. Therefore, even if there is a limit to the volume of the sample U that can be melted by levitation, it is possible to obtain a lens T that makes more effective use of the volume of the sample U.

[0084] <Tenth embodiment> In a glass manufacturing apparatus 10 according to the tenth embodiment, a support member 12 is replaceable with respect to a stage 11. Fig. 13 is a schematic diagram (cross-sectional view) showing an example of the vicinity of a levitation furnace in the tenth embodiment. Fig. 13(A) is a schematic diagram (cross-sectional view) showing an example of the vicinity of a levitation furnace in the tenth embodiment, and Fig. 13(B) is a schematic diagram (cross-sectional view) showing a modified example of the levitation furnace in the tenth embodiment.

[0085] In this embodiment, the glass manufacturing apparatus 10 includes a fixing member 25. The material of the fixing member 25 can be selected appropriately, but it is preferable that at least a part or the whole of the fixing member 25 is made of stainless steel (SUS), an aluminum alloy, or the like.

[0086] The material of the support member 12 can be selected appropriately, but is preferably, for example, stainless steel (SUS), aluminum alloy, silicon carbide (SiC), brass, or the like. The support member 12 includes a base 121 having a first surface W1 and a second surface W2 shown in FIG. 2, and a locking portion 122 that locks to the stage 11. The stage 11 is made of, for example, stainless steel (SUS), aluminum alloy, or the like, and includes a nozzle 111 that connects to the gas flow regulator 20 and supplies gas to the support member 12, and a fixing wall 112 that rises approximately vertically upward. The gas flow regulator 20 and the nozzle 111 function as a gas supply unit that supplies gas to levitate the sample U. The fixing wall 112 has, for example, a circular horizontal cross section and functions to isolate the space filled with gas to prevent the gas ejected from the nozzle 111 from leaking outward.

[0087] The locking portion 122 is locked to the upper part of the fixing wall 112. In other words, the stage 11 supports the support member 12 from below. The support member 12 is removable from the stage 11. The base 121 is located inside the fixing wall 112. As shown in FIG. 13(A), there may be a gap between the base 121 and the fixing wall 112. For example, if there is a hole for introducing gas on the side surface of the base 121, the presence of the gap will allow the gas to be ejected from the hole on the side surface to the first surface W1. It is noted that there does not have to be a gap between the base 121 and the fixing wall 112.

[0088] The fixing member 25 is provided above the support member 12 and fixes the support member 12 to the stage 11. For example, as shown in Fig. 13(A), the fixing member 25 has a horizontal surface 25a that covers a part of the support member 12 and a side surface 25b that is connected vertically to the end of the horizontal surface 25a, and the horizontal surface 25a is open near the center so as to expose the concave surface R of the support member 12.

[0089] For example, the support member 12 is fixed to the stage 11 by a screw structure. Specifically, the inside of the side surface 25b of the fixing member 25 is threaded so as to fit into a part of the fixing wall 112. When the fixing member 25 is rotated relative to the stage 11, the fixing member 25 is fixed to the stage 11. As a result, a part of the support member 12 is sandwiched between the fixing member 25 and the fixing wall 112, and the support member 12 is fixed to the stage 11.

[0090] The method for fixing the fixing member 25 to the stage 11 is not limited to this example. For example, the fixing member 25 may be fixed to the stage 11 by providing a through hole in the side surface 25b and screwing the fixing member 25 through the through hole into a screw hole provided from the outside to the inside of the fixing wall 112.

[0091] 13(B), the glass manufacturing apparatus 10 may be configured so that the support member 12 is fixed to the stage 11 without using the fixing member 25. In this case, for example, the inner surface of the fixing wall 112 is threaded so as to fit with a part of the side surface of the support member 12. The support member 12 is fixed to the stage 11 by rotating the support member 12 relative to the fixing wall 112.

[0092] As described above, when the forming unit 30 is pressed against the sample U from above to form it, the shape of the concave surface R of the support member 12 is transferred to the bottom of the sample U. The shape of the concave surface R of the support member 12 can be appropriately designed, such as a lens shape, an aspherical lens shape, a shape with a flat center, or a shape with a concave or convex center. The diameter of the concave surface R can also be designed according to the desired glass size. According to the glass manufacturing apparatus 10 of this embodiment, multiple support members 12 are prepared, and after removing the first support member 12, the second support member 12 can be fixed to the stage 11. This allows for easy replacement with the desired support member 12. When replacing the support member 12 in the glass manufacturing apparatus shown in FIG. 13(A), first, the fixing member 25 is removed from the stage 11. Next, the first support member 12 is removed from the stage 11, and the second support member 12 is supported by the stage 11, and the fixing member 25 is then attached again.

[0093] Incidentally, an aluminum alloy can be used for the support member 12, from the viewpoints that the concave surface R can be easily machined and that the dissolution of impurities into the sample U is suppressed. Furthermore, when an aluminum alloy is used for the support member 12, stainless steel (SUS) or the like, which has a lower thermal conductivity than aluminum alloy, can be used for the stage 11 in order to suppress the gradient of temperature change throughout the levitation furnace. The support member 12 may deteriorate faster than the stage 11. According to the glass manufacturing apparatus 10 of this embodiment, when a support member 12 that deteriorates more easily than the stage 11 is used, the support member 12 can be easily replaced.

[0094] <Heating control> 14A and 14B are diagrams for explaining heating control of sample U in the first to tenth embodiments. FIG. 14A is a diagram (part 1) showing an example of a standard heating amount, FIG. 14B is a diagram (part 2) showing an example of a standard heating amount, and FIG. 14C is a diagram showing an example of a state in which the heating amount is reduced. As mentioned above, the processing target of glass manufacturing apparatus 10 may be referred to as "sample U."

[0095] The control unit 22 of the glass manufacturing apparatus 10 functions as a heating control unit that controls the amount of heat applied to the sample U by controlling the output of the laser light source 13 based on the temperature information from the radiation thermometer 16. The control unit 22 changes the amount of heat, for example, to change the temperature of the sample U to a temperature below the deformation point and above the glass transition point. For example, the control unit 22 reduces the amount of heat by lowering the output of the laser light source 13, thereby changing the state of the laser light L shown in FIG. 14(A) to the state of the laser light L shown in FIG. 14(C). As a result, the shaping unit 30 shapes the sample U in a molten state whose temperature has changed based on the control of the amount of heat by the control unit 22. The shaping unit 30 can shape the sample U while the temperature of the sample U is decreasing. The shaping unit 30 shapes the sample U at a temperature below the deformation point and above the glass transition point, for example. The control unit 22 may also reduce the amount of heat by lowering the output of the laser light source 13 to zero.

[0096] Furthermore, for example, the control unit 22 reduces the amount of heat by reducing the number of lasers output by the laser light source 13, and changes the state of the laser light L shown in FIG. 14(B) to the state of the laser light L shown in FIG. 14(C). As a result, similar to the example shown in FIG. 14(A), the forming unit 30 forms the sample U in a molten state, the temperature of which has changed based on the control of the amount of heat by the control unit 22. Note that the control unit 22 may reduce the amount of heat by stopping heating by some of the multiple heating devices.

[0097] <Melting process and molding process> In the first to tenth embodiments described above, in the melting step, the sample U supported by the levitation unit 21 in a non-contact manner is heated and melted by the heating unit (laser light source 13). In this step, the laser light source 13 may heat the sample U placed in contact with the support member 12 to melt at least a portion of it, and then the levitation unit 21 may levitate the sample U and further heat it. Alternatively, the levitation unit 21 may melt the sample U placed on the support member 12 and levitate the molten sample U. The levitation unit 21 may stop levitating the sample U if the temperature is such that devitrification will not occur. In other words, it is preferable that the levitation unit 21 support the sample U in a non-contact manner at least from the completion of melting of the raw materials contained in the sample U until the sample is cooled to a temperature that will not cause devitrification. This prevents devitrification due to contact between the sample U and the support member 12 during the cooling step.

[0098] Furthermore, in the first to tenth embodiments described above, the forming process by the forming unit 30 may be performed after irradiation of the laser light L has stopped, or may be performed during irradiation. In addition, even if the surface area of ​​the sample U irradiated with the laser light L is limited, the entire sample U can be adjusted to a desired temperature by convection through the sample U. The forming process may be performed at a temperature equal to or higher than the glass transition point of the sample U and at a temperature that does not cause devitrification. Furthermore, the forming process may be performed in a state where the sample U is floating in a gas, i.e., in a state where the sample U is not in contact with the support member 12, or in a state where the sample U is in contact with the support member 12.

[0099] Furthermore, before or during molding by the molding unit 30, control may be exercised to eject gas from the support member 12, or control may be exercised to stop the ejection of gas. The control unit controls the ejection of gas from the support member 12 to stop at a timing when the sample U will not be devitrified. When it is desired to prevent deformation or damage to the sample U due to the ejection of gas, it is preferable to stop the ejection of gas.

[0100] In addition, the glass frit supported in contact or without contact with the support member 12 may be an unvitrified raw material or a glass that has been vitrified once. When the glass frit supported in a non-contact manner on the support member 12 is an unvitrified raw material, the glass frit may be, for example, a pressed compact of an oxide raw material powder or a sintered compact thereof, or an aggregate of crystals having the same composition as the desired glass.

[0101] <Example> Next, each example will be described, but the present invention is not limited to the following examples.

[0102] Example 1 First, the oxide raw materials were weighed to obtain a predetermined chemical composition and then mixed in an alumina mortar. This mixture was uniaxially pressed at 20 MPa to form cylindrical pellets. The resulting pellets were then fired in an electric furnace at 1200°C in air for 12 hours to produce sintered bodies. In this example, oxides were used as raw materials, but the raw materials are not limited to oxides. Specifically, hydroxides, carbonates, nitrates, sulfates, and phosphates may also be used as raw materials.

[0103] Next, this sintered body was roughly crushed and placed on a support member 12 of a glass manufacturing apparatus 10 shown in FIG. 1. The raw materials were then melted by irradiating them from above with a carbon dioxide laser while injecting air. The molten raw materials took on a roughly spherical shape due to their own surface tension and were suspended by the gas pressure. When the raw materials were completely melted, the laser output was shut off to cool them, and a sample U was obtained. The diameter φ and thickness t of the sample U at this point were measured.

[0104] Thereafter, pressure was applied to the periphery of the sample U using the molding member 31 shown in FIG. 3, and then the sample U was cooled. The diameter φ and thickness t of the cooled sample U were measured. Note that no devitrification was observed in the optical glass obtained after cooling.

[0105] <Example 2> The raw materials described below were weighed and then mixed in the same manner as in Example 1 to obtain pellets. The raw materials were then melted in the same manner as in Example 1, and the laser output was shut off to obtain a cooled sample U, after which the diameter φ and thickness t of the sample U were measured. The sample U was then sucked from above by the suction unit 32 shown in FIG. 4 and then cooled. The diameter φ and thickness t of the cooled sample U were measured.

[0106] Table 1 shows the composition of the raw materials used in each example.

[0107] [Table 1]

[0108] <Evaluation> Fig. 15 is a diagram showing the measurement results of Sample U obtained as a result of Examples 1 and 2. Fig. 15 confirms that the thickness of Sample U increased in all Examples. Note that no devitrification was observed in any of the glasses of the Examples.

[0109] From the above, it was confirmed that the glass manufacturing apparatus 10 of each example can stably manufacture optical glass having a desired diameter and thickness.

[0110] Example 3 The raw materials (sample U in raw material form) described separately were weighed and mixed in the same manner as in Example 1 to obtain pellets. The raw materials were then melted in the same manner as in Example 1, and the cooled sample U was obtained by shutting off the laser output. The pre-molding diameter (diameter of sample U) and the pre-molding thickest part thickness (thickness of the thickest part) were then measured. Next, the sample U was melted again by irradiating it from above with a carbon dioxide laser while spraying air. After shutting off the laser output, the sample U was pressed from above with a molding member 382, ​​the tip of which is concave on the sample U side, as shown in Figure 9(B), and then thoroughly cooled. The support member 12 used had a flat central portion of the concave surface R. The post-molding diameter (diameter of sample U after cooling), the post-molding thickest part thickness (thickness of the thickest part), and the post-molding thinnest part thickness (thickness of the thinnest part) were measured. No devitrification was observed in the optical glass obtained after cooling.

[0111] Example 4 The raw materials (sample U in raw material state) described separately were weighed and mixed in the same manner as in Example 1 to obtain pellets. The raw materials were then melted in the same manner as in Example 1, and the cooled sample U was obtained by shutting off the laser output. The pre-molding diameter (diameter of sample U) and the pre-molding thickest part thickness (thickness of the thickest part) were measured. Next, the sample U was melted again by irradiating it from above with a carbon dioxide laser while spraying air. After shutting off the laser output, the sample U was pressed from above with a molding member 381, the tip of which is flat on the sample U side, as shown in FIG. 9(A), and then thoroughly cooled. The support member 12 used had a flat central portion of the concave surface R. The post-molding diameter (diameter of sample U after cooling), the post-molding thickest part thickness (thickness of the thickest part), and the post-molding thinnest part thickness (thickness of the thinnest part) were measured. No devitrification was observed in the optical glass obtained after cooling.

[0112] <Example 5> The raw materials (sample U in raw material state) described separately were weighed and mixed in the same manner as in Example 1 to obtain pellets. The raw materials were then melted in the same manner as in Example 1, and the cooled sample U was obtained by shutting off the laser output. The diameter of sample U (pre-molding diameter) and the thickness of its thickest portion (pre-molding thickness) were then measured. Next, sample U was melted again by irradiating it from above with a carbon dioxide laser while injecting air. After shutting off the laser output, sample U was molded in the molding unit 30 shown in FIG. 11(A) and then sufficiently cooled. Specifically, in the molding unit 30, sample U was surrounded by auxiliary member 387, and pressure was applied from above to sample U using molding member 386. The molding member 386 had a convex tip on the sample U side. The support member 12 had a concave surface R with a flat central portion.

[0113] The diameter of sample U after cooling, i.e., the diameter after molding, the thickness of the thickest part after molding, i.e., the thickness of the thinnest part after molding, i.e., the thickness of the thickest part, i.e., the thickness of the thinnest part, i.e., the thickness of the thinnest part after molding, were measured. Note that no devitrification was observed in the optical glass obtained as a result of cooling.

[0114] Example 6 The raw materials (sample U in the raw material state) described separately were weighed and then mixed in the same manner as in Example 1 to obtain pellets. Thereafter, the raw materials were melted in the same manner as in Example 1, and two samples U were prepared by cooling them by cutting off the laser output. The weights of the obtained samples U1 and U2 were measured.

[0115] Sample U1 was melted by irradiating it from above with a carbon dioxide laser while injecting air, then the laser output was shut off and pressure was applied from the surroundings using the molding member 31 shown in Figure 3, after which it was thoroughly cooled. The diameter and thickness of sample U1 were measured after cooling. No devitrification was observed in the optical glass obtained after cooling.

[0116] The specimen U2 was melted by irradiating it from above with a carbon dioxide gas laser while injecting air, and then the laser output was shut off, and pressure was applied from the surroundings using the forming member 390 shown in FIG. 12, and then the specimen was sufficiently cooled. A diameter of the lower part UB The diameter of the support member 12 was measured. As with the support member 12 used in forming sample U1, the shape of the central portion of the concave surface R of the support member 12 was flat. No devitrification was observed in the optical glass obtained after cooling. A and the lower part U B is the same as the example shown in FIG.

[0117] Table 2 shows the compositions of the raw materials used in Examples 3 to 6.

[0118] [Table 2]

[0119] <Evaluation> FIG. 16 shows the measurement results of sample U obtained in Examples 3 to 5. In Example 3, the shape of the molding member 382 used was transferred to sample U, resulting in an optical glass in which the central portion had the thickest thickness after molding and the edge portions had the thinnest thickness after molding. In Example 4, the shape of the tip of molding member 381 on the sample U side was flat, resulting in an optical glass in which the difference between the thickest thickness after molding and the thinnest thickness after molding was smaller than in the other Examples. In Example 5, the shape of molding member 386 was transferred to sample U, resulting in an optical glass in which the central portion had the thinnest thickness after molding and the edge portions had the thickest thickness after molding.

[0120] It was found that the diameter after molding was larger than the diameter before molding, and the thickness of the thickest part after molding was smaller than the thickness of the thickest part before molding in Examples 3 to 5. From the above, it was confirmed that the glass manufacturing apparatus of each Example can stably produce optical glass of the desired diameter and thickness.

[0121] 17A and 17B are diagrams showing the measurement results of sample U1 and sample U2 obtained as a result of Example 6. FIG. 17A shows the measurement results of sample U1, and FIG. 17B shows the measurement results of sample U2. Sample U1 was molded using the molding member 31 of FIG. 3, which has a flat contact surface on the sample U1 side, so the diameter was approximately constant from the top to the bottom. Sample U1 and sample U2 have the same weight, but sample U2, which was molded using molding member 390, has a lower portion U B The diameter of the lower part was smaller than that of sample U1, and the thickness was greater. In other words, it was confirmed that by using the molding member 390 shown in Figure 12, optical glass of the desired shape with a small diameter at the bottom can be stably produced.

[0122] In the above examples, in order to measure the shape of the glass before and after forming, the raw material is melted and cooled to obtain the pre-forming sample U (or U1, U2), and then the sample U is melted again and formed after the laser is stopped. However, it is clear that the formed sample U may be obtained by forming the raw material without going through the process of melting the raw material, stopping the laser, and cooling to obtain the pre-forming sample U.

[0123] <Optical elements, optical systems, interchangeable camera lenses, optical devices, etc.> The optical glass obtained by the glass manufacturing apparatus 10 according to each embodiment can be suitably used, for example, as an optical element provided in an optical instrument. Such optical elements include mirrors, lenses, prisms, filters, etc., and can be widely used as optical systems. The optical system according to the present embodiment can be suitably used as an interchangeable lens for a camera including the optical glass. Known configurations of such optical elements, optical lenses, and interchangeable lenses for cameras can be adopted. Furthermore, the optical system according to the present embodiment can be suitably used as an optical device including the optical system. Optical devices including such optical systems include, but are not limited to, imaging devices such as interchangeable lens cameras and non-interchangeable lens cameras, optical microscopes, and the like. Examples of these devices are described below.

[0124] (imaging device) FIG. 18 is a perspective view of an example in which the optical device according to each embodiment is used as an imaging device.

[0125] The imaging device 1 is a so-called digital single-lens reflex camera (interchangeable lens camera), and the photographing lens (optical system) 103 is equipped with the cured product according to this embodiment. A lens barrel 102 is detachably attached to a lens mount (not shown) of a camera body 101. Light passing through a lens 103 of the lens barrel 102 forms an image on a sensor chip (solid-state image sensor) 104 of a multi-chip module 106 disposed on the rear side of the camera body 101. This sensor chip 104 is a bare chip such as a so-called CMOS image sensor, and the multi-chip module 106 is, for example, a COG (chip on glass) type module in which the sensor chip 104 is bare-chip mounted on a glass substrate 105.

[0126] FIG. 19 is a front view of another example in which the optical device according to each embodiment is used as an imaging device, and FIG. 20 is a rear view of the imaging device.

[0127] The imaging device CAM is a so-called digital still camera (non-interchangeable lens camera), and the photographing lens (optical system) WL is equipped with the cured product according to this embodiment. When the power button (not shown) of the imaging device CAM is pressed, a shutter (not shown) of the photographing lens WL is opened, and light from the subject (object) is collected by the photographing lens WL and focused on an imaging element disposed on the image plane. The subject image focused on the imaging element is displayed on an LCD monitor M disposed behind the imaging device CAM. After determining the composition of the subject image while looking at the LCD monitor M, the photographer presses the release button B1 to capture the subject image with the imaging element and record and save it in memory (not shown). The imaging device CAM is equipped with an auxiliary light emitter EF that emits auxiliary light when the subject is dark, a function button B2 used to set various conditions for the imaging device CAM, and other devices.

[0128] Optical systems used in such digital cameras and the like are required to have higher resolution, lighter weight, and smaller size. To achieve these, it is effective to use optical glass with a high refractive index in the optical system. From this perspective, the optical glass according to each embodiment is suitable as a component of such optical equipment. Note that optical equipment to which each embodiment can be applied is not limited to the imaging device described above, but also includes, for example, projectors, etc. Optical elements are also not limited to lenses, but include, for example, prisms, etc.

[0129] (multiphoton microscope) FIG. 21 is a block diagram showing an example in which the optical device according to each embodiment is a multiphoton microscope.

[0130] The multiphoton microscope 2 includes, as optical elements, an objective lens 206, a condenser lens 208, and an imaging lens 210. The following description will focus on the optical system of the multiphoton microscope 2.

[0131] The pulsed laser device 201 emits ultrashort pulsed light, for example, with a near-infrared wavelength (approximately 1000 nm) and a pulse width in femtosecond units (for example, 100 femtoseconds). The ultrashort pulsed light immediately after being emitted from the pulsed laser device 201 is generally linearly polarized in a predetermined direction.

[0132] The pulse splitting device 202 splits the ultrashort pulsed light, increases the repetition frequency of the ultrashort pulsed light, and emits it.

[0133] The beam adjusting unit 203 has functions such as a function to adjust the beam diameter of the ultrashort pulsed light incident from the pulse splitter 202 to match the pupil diameter of the objective lens 206, a function to adjust the focusing and divergence angles of the ultrashort pulsed light in order to correct the axial chromatic aberration (focus difference) between the wavelength of the multiphoton excitation light emitted from the sample S and the wavelength of the ultrashort pulsed light, and a pre-chirp function (group velocity dispersion compensation function) to impart an inverse group velocity dispersion to the ultrashort pulsed light in order to correct the pulse width of the ultrashort pulsed light being widened by group velocity dispersion while passing through the optical system.

[0134] The repetition frequency of the ultrashort pulsed light emitted from the pulsed laser device 201 is increased by the pulse dividing device 202, and the above-mentioned adjustment is performed by the beam adjusting unit 203. Then, the ultrashort pulsed light emitted from the beam adjusting unit 203 is reflected by the dichroic mirror 204 in the direction of the dichroic mirror 205, passes through the dichroic mirror 205, and is collected by the objective lens 206 to be irradiated onto the sample S. At this time, the ultrashort pulsed light may be scanned over the observation surface of the sample S by using a scanning means (not shown).

[0135] For example, when observing the fluorescence of a sample S, the fluorescent dye with which the sample S is stained undergoes multiphoton excitation in the area of ​​the sample S irradiated with the ultrashort pulsed light and in its vicinity, emitting fluorescence (hereinafter referred to as "observation light") with a wavelength shorter than that of the ultrashort pulsed light, which is an infrared wavelength.

[0136] Observation light emitted from the sample S in the direction of the objective lens 206 is collimated by the objective lens 206 and is either reflected by or transmitted through the dichroic mirror 205 depending on its wavelength.

[0137] The observation light reflected by the dichroic mirror 205 enters the fluorescence detection unit 207. The fluorescence detection unit 207 is configured with, for example, a barrier filter, a PMT (photomultiplier tube), etc., receives the observation light reflected by the dichroic mirror 205, and outputs an electrical signal according to the amount of light. Furthermore, the fluorescence detection unit 207 detects the observation light across the observation surface of the sample S as the ultrashort pulsed light scans the observation surface of the sample S.

[0138] On the other hand, the observation light that has passed through the dichroic mirror 205 is descanned by a scanning means (not shown), passes through the dichroic mirror 204, is focused by the focusing lens 208, passes through a pinhole 209 located at a position approximately conjugate with the focal position of the objective lens 206, passes through an imaging lens 210, and enters the fluorescence detection unit 211.

[0139] The fluorescence detection unit 211 is configured with, for example, a barrier filter, a PMT, etc., receives the observation light imaged on the light receiving surface of the fluorescence detection unit 211 by the imaging lens 210, and outputs an electrical signal according to the amount of light. Furthermore, the fluorescence detection unit 211 detects the observation light across the observation surface of the sample S as the ultrashort pulsed light scans the observation surface of the sample S.

[0140] It is also possible to remove the dichroic mirror 205 from the optical path so that all of the observation light emitted from the sample S in the direction of the objective lens 206 is detected by the fluorescence detection unit 211 .

[0141] Furthermore, observation light emitted from the sample S in the direction opposite to the objective lens 206 is reflected by the dichroic mirror 212 and enters the fluorescence detection unit 213. The fluorescence detection unit 213 is configured, for example, with a barrier filter, a PMT, etc., and receives the observation light reflected by the dichroic mirror 212 and outputs an electrical signal according to the amount of light. Furthermore, the fluorescence detection unit 213 detects the observation light across the observation surface of the sample S as the ultrashort pulsed light scans the observation surface of the sample S.

[0142] The electrical signals output from the fluorescence detection units 207, 211, and 213 are input, for example, to a computer (not shown), which can generate an observation image based on the input electrical signals, display the generated observation image, and store the data of the observation image.

[0143] <Cemented lens> FIG. 22 is a schematic diagram showing an example of a cemented lens according to each embodiment. The cemented lens 3 is a compound lens having a first lens element 301 and a second lens element 302. At least one of the first lens element and the second lens element uses the optical glass according to each embodiment. The first lens element and the second lens element are cemented together via a cementing member 303. A known adhesive or the like can be used as the cementing member 303. Note that the lenses that make up the cemented lens may be referred to as "lens elements" as described above, to clarify that they are elements of the cemented lens.

[0144] The cemented lens according to each embodiment is useful from the viewpoint of correcting chromatic aberration, and can be suitably used in the optical elements, optical systems, optical devices, etc. described above. Furthermore, optical systems including cemented lenses can be particularly suitably used in interchangeable lenses for cameras, optical devices, etc. While the cemented lens using two lens elements has been described in the above-described embodiments, this is not limiting, and a cemented lens using three or more lens elements may also be used. When a cemented lens using three or more lens elements is used, it is sufficient that at least one of the three or more lens elements is formed using the optical glass according to this embodiment. [Explanation of symbols]

[0145] 1...imaging device (interchangeable lens camera), 10...glass manufacturing device, 11...stage, 12...support member, 13...laser light source, 14, 15...mirror, 16...radiation thermometer, 17...computer, 18...CCD camera, 19...monitor, 20...gas flow regulator, 21...floating unit, L: laser light, 22...control unit, 23...calculation unit, 24...nozzle, R: concave surface, U: sample, W1: first surface , W2...second surface, 30...molded portion, 31a, 31b, 31c, 31d, 31e, 31f, 31g, 31h, 33, 35, 35a, 35b, 36a, 36b, 381, 382, ​​383, 384, 385, 386, 390...molded member, 387...auxiliary member, 388...first molded member, 389...second molded member, 112...fixing wall, 121...base, 122...locking portion, 25...fixed fixing member, 25a... horizontal surface, 25b... side surface, 32... suction portion, 34...111... nozzle, 37... dividing portion, 101... camera body, 102... lens barrel, 103... lens, 104... sensor chip, 105... glass substrate, 106... multi-chip module, H... hole, T... lens, CAM... imaging device (non-interchangeable lens camera), WL... photographing lens, M... liquid crystal monitor, EF... fill light emitting portion, B1... release button, B2... function button, 2... multi-photon microscope, 201... pulse laser device, 202... pulse splitting device, 203... beam adjusting portion, 204, 205, 212... dichroic mirror, 206... objective lens, 207, 211, 213... fluorescence detection portion, 208... condensing lens, 209... pinhole, 210... imaging lens, S·U... sample, U A ...Upper part, U B ...lower portion, 3...cemented lens, 301...first lens element, 302...second lens element, 303...cemented member

Claims

1. A glass manufacturing apparatus for manufacturing glass through a step of lowering the temperature of glass raw materials supported in a non-contact manner, comprising: A heating section for heating the glass raw material; A heating control unit for controlling the amount of heat of the glass frit by the heating unit; and a forming unit that forms the glass frit in a molten state during a period in which the temperature of the glass frit is reduced based on the control of reducing the amount of heat by the heating control unit.

2. The heating section heats the glass raw material by a plurality of heating devices, The glass manufacturing apparatus according to claim 1 , wherein the heating control unit reduces the amount of heat by stopping heating by some of the plurality of heating devices.

3. The heating control unit changes the temperature of the glass raw material in a molten state to a temperature equal to or lower than a deformation point by changing the amount of heat applied by the heating unit, The glass manufacturing apparatus according to claim 1 , wherein the forming section forms the glass raw material in a molten state at a temperature equal to or lower than the deformation point.

4. The heating control unit changes the temperature of the glass raw material in a molten state to a temperature equal to or higher than the glass transition point of the glass by changing the amount of heat applied by the heating unit, The glass manufacturing apparatus according to claim 1 , wherein the forming section forms the glass raw material in a molten state having a temperature equal to or higher than the glass transition point.

5. 2. The glass manufacturing apparatus according to claim 1, wherein the forming section has a forming member for forming a shape of the glass raw material in a molten state, and the forming member is pressed against the glass raw material in a molten state to form the glass raw material.

6. The glass manufacturing apparatus according to claim 5 , wherein the shaping unit has a plurality of the shaping members, and the plurality of the shaping members are pressed against the glass frit in a molten state to shape the glass frit in a molten state.

7. 6. The glass manufacturing apparatus according to claim 5, wherein the shaping unit has four or more shaping members, and drives the shaping members within a predetermined plane to shape the glass raw material in a molten state.

8. The glass manufacturing apparatus according to any one of claims 5 to 7, wherein the shaping member is arc-shaped.

9. The glass manufacturing apparatus according to any one of claims 5 to 7, wherein a cross section of the forming member in a gravity direction is L-shaped.

10. The glass manufacturing apparatus according to claim 5 , wherein the forming unit presses the forming member against an upper portion of the glass frit in a molten state to form the glass frit in a molten state.

11. A support part capable of supporting the glass raw material in a contact and non-contact manner, The glass manufacturing apparatus according to claim 10 , wherein the shaping unit presses the shaping member against the glass raw material in a molten state from above, and shapes the glass raw material in a molten state by sandwiching it between the support unit and the shaping member.

12. 12. The glass manufacturing apparatus according to claim 10, wherein the forming unit has an auxiliary member surrounding the molten glass frit, and the forming member is pressed against the molten glass frit surrounded by the auxiliary member to form the molten glass frit.

13. The glass manufacturing apparatus according to claim 12 , wherein the auxiliary member is cylindrical.

14. 6. The glass manufacturing apparatus according to claim 5, wherein the forming unit presses a first forming member of the forming members against the glass frit in the molten state from above, and drives a plurality of forming members different from the first forming member in a predetermined plane intersecting with the gravity direction to press the glass frit in the molten state, thereby forming the glass frit in the molten state.

15. 2. The glass manufacturing apparatus according to claim 1, wherein the forming unit has a suction unit, and the glass raw material in a molten state is sucked by the suction unit to form the glass raw material.

16. The glass manufacturing apparatus according to claim 15 , wherein the forming portion is cylindrical.

17. The forming unit has a suction unit that sucks the glass frit in a molten state and a forming member that forms the glass frit in a molten state, 2. The glass manufacturing apparatus according to claim 1, wherein the molten glass frit is shaped by sucking the molten glass frit with the suction part and pressing the shaping member against the molten glass frit.

18. The glass manufacturing apparatus according to claim 17 , wherein the suction unit is provided in the shaping unit so as to surround the shaping member with respect to a plane perpendicular to a gravity direction.

19. A support part capable of supporting the glass raw material in a contact and non-contact manner, The glass manufacturing apparatus according to any one of claims 1 to 5, 15, and 17, wherein the supporting part has a nozzle from which a gas is ejected, and the glass raw material is supported in a non-contact manner by the gas ejected from the nozzle.

20. The glass manufacturing apparatus according to claim 19 , wherein the supporting unit stops ejection of the gas before or during shaping of the glass raw material by the shaping unit.

21. The glass manufacturing apparatus according to claim 5 , wherein the melting point of the forming member is 500° C. or higher.

22. The glass manufacturing apparatus according to claim 5 , wherein the forming member is made of an aluminum alloy.

23. A support part capable of supporting the glass raw material in a contact and non-contact manner, The glass manufacturing apparatus according to any one of claims 1 to 5, 15, and 17, wherein the supporting part supports the glass raw material in a non-contact manner by static electricity.

24. The glass manufacturing apparatus according to any one of claims 1 to 5, 15, and 17, wherein the heating section heats the glass raw material supported in a non-contact manner.

25. The glass manufacturing apparatus according to any one of claims 1 to 5, 15, and 17, wherein the heating unit is a laser.

26. The glass manufacturing apparatus according to any one of claims 1 to 5, 15 and 17, wherein the glass raw material is a press-molded body or a sintered body thereof, or an aggregate of crystals.

27. A method for producing glass, comprising producing glass using the glass production apparatus according to any one of claims 1 to 5, 15 and 17.

28. A method for producing glass by a step of lowering the temperature of non-contact supported glass raw materials, comprising: a melting step of heating and melting the glass raw material by a heating unit; A heating control step of controlling the amount of heat of the glass frit by the heating unit; and a forming step of forming the glass raw material in a molten state, the temperature of which has been changed by controlling the amount of heat in the heating control step.

29. The method for producing glass according to claim 28 , wherein in the forming step, the glass raw material in a molten state is formed by a forming unit at a temperature equal to or higher than a glass transition point and equal to or lower than a deformation point of the glass.

30. A glass manufacturing apparatus for manufacturing glass by cooling a glass raw material, A support member for supporting the glass raw material in a molten state in a non-contact manner; a stage to which the support member is fixed; The glass manufacturing apparatus, wherein the support member is removable from the stage.

31. The glass manufacturing apparatus of claim 30 , wherein the support member is fixed to the stage by a screw structure.

32. The glass raw material in a molten state is supported in a non-contact manner by a second support member different from the first support member, 32. The glass manufacturing apparatus of claim 31 , wherein the second support member is secured to the stage after the first support member is removed.

33. a fixing member that fixes the support member to the stage, The stage supports the support member from below, The glass manufacturing apparatus according to any one of claims 30 to 32, wherein the fixing member is provided above the support member.

34. The glass manufacturing apparatus according to claim 33, wherein the fixing member is made of stainless steel (SUS) or an aluminum alloy.

35. A gas supply unit for supplying a gas for floating the glass raw material in a molten state, The glass manufacturing apparatus according to any one of claims 30 to 32, wherein the support member has a nozzle through which the gas supplied by the gas supply unit is ejected, and the glass raw material in a molten state is floated above the support member by the gas ejected from the nozzle to be supported in a non-contact manner.

36. The glass manufacturing apparatus according to any one of claims 30 to 32, wherein the material of the support member is stainless steel (SUS), aluminum alloy, silicon carbide (SiC), or brass.

37. The glass manufacturing apparatus of claim 19, wherein the forming section forms the molten glass raw material during at least a portion of the period during which the gas is ejected from the nozzle and sprayed onto the molten glass raw material on the support section.

Images