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

Abstract

To provide a method for manufacturing optical glass, capable of stably floating a glass sample with floating gas in a laser floating furnace.SOLUTION: A glass manufacturing apparatus capable of cooling the melt of a glass raw material supported in a non-contact to manufacture glass includes: a heating part for heating the glass raw material; a support part for supporting the melt of the glass raw material in a non-contact; and a molding part for molding the melt of the glass raw materials in a non-contact by the support 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] JP 2014-196236 A Summary of the Invention

[0004] An aspect of the present invention is, for example, a glass manufacturing apparatus for manufacturing glass by cooling a molten liquid of glass frits supported in a non-contact manner, the apparatus comprising: a heating section for heating the glass frits; a supporting section for supporting the molten liquid of the glass frits in a non-contact manner; and a forming section for forming the molten liquid of the glass frits supported in a non-contact manner by the supporting section.

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

[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-mentioned optical system.

[0008] Another aspect of the present invention is a glass manufacturing method for obtaining glass by heating, melting, and cooling levitated glass frits, the method including a melting step of heating and melting the glass frits, a levitation step of levitating the glass frits or the molten glass, a stopping step of stopping heating the molten glass, a cooling step of cooling the molten glass to obtain the glass, and a shaping step of heating the glass and deforming a shape of the glass using a shaping member. [Brief description of the drawings]

[0009] [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. [Diagram 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. [Diagram 3] Fig. 3 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment. Fig. 3(A) is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment, Fig. 3(B) is a view (part 1) of the shaping member 31 seen from the support member 12 side, and Fig. 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. [Diagram 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] 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 schematic diagram No. 1 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment, and Fig. 8(B) is a schematic diagram No. 2 (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 forming 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 forming method of the sample U using the forming member 383. [Figure 10] FIG. 10 is a diagram showing the measurement results of the samples obtained in each example. [Figure 11] FIG. 11 is a perspective view of an example in which the optical device according to each embodiment is used as an imaging device. [Figure 12] FIG. 12 is a front view of another example in which the optical device according to each embodiment is used as an imaging device. [Figure 13] FIG. 13 is a rear view of another example in which the optical device according to each embodiment is used as an imaging device. [Figure 14] FIG. 14 is a block diagram showing an example in which the optical device according to each embodiment is a multiphoton microscope. [Figure 15] FIG. 15 is a schematic diagram showing an example of a cemented lens according to each embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] 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.

[0011] In the drawings, the same elements are given the same reference numerals, and duplicated explanations are 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 the ratios shown in the drawings.

[0012] Furthermore, a term with "abbreviation" indicates the meaning of the term without "abbreviation" within the scope of the common technical knowledge of a person skilled in the art, and includes the meaning without "abbreviation". And vice versa. For example, the term "circle" does not have "abbreviation" attached, but it naturally includes the meaning of "approximately circle" as long as it is not contrary to the gist of the invention.

[0013] Further, the "cross section" in "cross section" 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 perpendicular to the horizontal plane.

[0014] <Outline of Glass Manufacturing Equipment 10>

[0015] 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 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.

[0016] As shown in FIG. 1, the glass manufacturing apparatus 10 is an optical glass manufacturing apparatus equipped with a gas jet type levitation furnace. The glass manufacturing apparatus 10 manufactures glass by heating and melting glass raw materials in a state where the glass raw materials are levitated by gas. The 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 the sample U, a laser light source 13 that irradiates the levitated sample U with a laser light L, a radiation thermometer 16 that measures the temperature of the levitated sample U, a computer 17 having a control unit 22 (not shown) that controls the output of the laser light source 13, the support member 12, and a forming unit 30 described later based on temperature information from the radiation thermometer 16, and a gas flow regulator 20 that adjusts the flow rate of gas supplied to the support member 12. The support member 12 and the gas flow regulator 20 are included in a levitation unit 21 that levitates the sample U.

[0017] In the glass manufacturing apparatus 10, the sample U floating above the support member 12 arranged on the stage 11 is heated in a non-contact manner by irradiation with the laser light L. In other words, the laser light source 13 that irradiates the laser light L functions as a heating unit. As a result, the sample U melts and becomes a molten liquid having a substantially spherical or substantially ellipsoidal shape due to its own surface tension, and floats in that state.

[0018] 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 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.

[0019] The flow rate of the gas fed to 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 a nozzle (not shown) connected to the support member 12 is not particularly limited, and any known method can be used as appropriate.

[0020] After the stably levitated sample U is heated in a non-contact manner, the laser light L is cut off, whereby the melt (sample U) is cooled and solidified, yielding optical glass.

[0021] In this embodiment, external pressure is applied to the sample U in a molten state to form it into a desired thickness and size. The sample U is then cooled and solidified. The optical glass thus obtained can be processed into a desired shape as necessary and polished to form a desired optical element.

[0022] 2, the support member 12 has a first surface W1 having a concave surface R facing the sample U, and a second surface W2 that is a gas introduction surface located on the opposite side to the first surface W1. 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 for ejecting the gas. The gas introduced from the inlet is ejected from the outlet, causing the sample U to float.

[0023] The support member 12 may be any member capable of levitating 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 ejecting 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.

[0024] Furthermore, for example, the support member 12 may levitate the sample U using static electricity. In that 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 constituting 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 type, an acoustic type, a magnetic type, or the like.

[0025] <First embodiment> Fig. 3 is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment. Fig. 3(A) is a schematic diagram (cross-sectional view) showing an example of the vicinity of the levitation furnace in the first embodiment, Fig. 3(B) is a view (part 1) of the shaping member 31 seen from the support member 12 side, and Fig. 3(C) is a view (part 2) of the shaping member 31 seen from the support member 12 side.

[0026] 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 optical glass. At this time, the thickness of the sample U is limited due to the relationship between the surface tension acting on the sample U and gravity.

[0027] The glass manufacturing apparatus 10 in this embodiment makes it possible to obtain optical glass having a desired thickness by shaping the molten sample U during the temperature drop process.

[0028] Glass manufacturing apparatus 10 in the first embodiment includes a levitation unit 21 including a support member 12 and a gas flow regulator 20, a stage 11, a laser light source 13, mirrors 14 and 15, a radiation thermometer 16, a computer 17 having a control unit 22, a CCD camera 18, a monitor 19, and a shaping unit 30 that is levitated by levitation unit 21 and shapes a molten glass raw material liquid.

[0029] The shaping unit 30 has shaping members 31 (31a and 31b), and as shown in FIG. 3(A), presses the shaping members 31 against the molten glass to shape it. The shaping members 31 deform the shape of the melt of the sample U. As an example, there are multiple shaping members 31, and they are multiple claw-like members that are 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 driving it to be able to open and close freely, the sample U is sandwiched from multiple different directions. That is, the shaping unit 30 presses the multiple shaping members 31 against the melt of the sample U from multiple directions toward the center to shape it.

[0030] The material of the forming member 31 is not particularly limited, but 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 wettability with glass is appropriately suppressed, so that the generation of crystal points in the molten glass can be suppressed. In addition, the melting point of the material of the part of the forming member 31 that contacts the molten glass is preferably 500 degrees or higher, since it is desired that the material does not deform even at high temperatures.

[0031] As an example, the forming 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 forming members 31 and the specimen U as viewed from below (the support member 12 side). The forming members 31 (31c-f) are arranged to surround the specimen U. In this embodiment, the surface of the forming members 31 that comes into contact with the specimen U is in the shape of a circular arc. A pair of claw-shaped forming members (31c-31d) constituting each set of the forming members 31 moves in the +X direction or the -X direction, and the other pair of claw-shaped forming members (31e-31f) moves in the +Y direction or the -Y direction. That is, the forming members 31 can be opened and closed to sandwich and form the specimen U from four directions (+X direction, -X direction, +Y direction, -Y direction).

[0032] 3(B), the length of the sample U in the Z-axis direction can be increased while changing the shape of the sample U. The arrangement and number of the shaping members 31 are not limited to this, but may be four or more. In this case, the shaping unit 30 presses the shaping members 31 against the molten glass from four or more directions to shape it. The shape of the shaping members 31 that come into contact with the sample U is designed as appropriate.

[0033] 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 contacts 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. Not limited to this, the shape of the sample U can be formed according to the application by changing the number of forming members 31 and the shape of the surface that contacts the sample U. The forming member 31 can reduce the effort required to process the vitrified sample U. In addition, in order 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 forming.

[0034] After the laser irradiation by the laser light source 13 is 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, 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 applying pressure to 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.

[0035] Furthermore, the specimen U is molded by the molding member 31 up to a temperature at which the specimen U no longer deforms. When the temperature of the specimen U becomes lower than the temperature at which the specimen U no longer deforms, the specimen U may be removed from the molding member 31 and cooled. The temperature at which the specimen U no longer deforms is preferably a temperature equal to or lower than the glass transition point (glass transition temperature) of the specimen U.

[0036] 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. When molding is performed using the molding member 31 at a temperature above the deformation point, there is a possibility that crystallization will occur due to excessive wettability when the molding member 31 comes into contact with the sample U, resulting in devitrification. The sample U, which is between the glass transition point and the deformation point, has a viscosity suitable for molding by pressure and has suppressed excessive wettability with respect to the molding member 31, so that an optical glass of the desired thickness and size can be obtained more efficiently.

[0037] Incidentally, it is preferable to use the control unit 22 to determine the timing of forming the sample U by the forming unit 30. Before forming the sample U, the control unit 22 acquires information on the physical property values, 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 preferable temperature. Note that the physical property values ​​are not limited to these, and also include physical property values ​​required when the forming unit 30 forms the glass melt.

[0038] 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 timing of forming the sample U is above the glass transition point and below the deformation point.

[0039] 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 of molding 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 the 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 by also using the information on the weight of the raw material of the sample U, more preferable timing can be calculated. The calculation unit 23 may use not only the weight of the raw material of the sample U but also the size (volume, surface area, etc.) of the sample U.

[0040] In this embodiment, the sample U is successively melted and molded, but the sample U that has already been vitrified may be used as the sample to be molded. 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. After that, the laser irradiation is stopped again, and the sample U is molded by the molding unit 30 at a temperature equal to or lower than the yield point and equal to or higher than the glass transition point.

[0041] <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 section 30 in the second embodiment includes a suction section 32 instead of the shaping member 31. The suction section 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 molten glass to shape it.

[0042] The suction part 32 has a tapered cross section, with the inside of the tip gradually narrowing as it advances 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, the suction part 32 is preferably made of at least a part or all of stainless steel (SUS), aluminum alloy, quartz, or carbon.

[0043] After the laser irradiation by the laser light source 13 is stopped, the forming unit 30 forms the sample U using the suction unit 32 arranged at a position where the sample U can be sucked in. The suction unit 32 is preferably arranged directly above the sample U at a position where its center coincides 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 part of the sample U is sucked upward, increasing the thickness of the sample U in the Z-axis direction. Thereafter, the sample U is removed from the forming unit 30 and cooled to obtain optical glass of the desired thickness.

[0044] <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. The following describes the differences from the second embodiment. The forming unit 30 in this modified example has a forming member 33 in addition to the suction unit 32. The forming member 33 forms a sample U that is molten glass.

[0045] The shaping member 33 functions as a mold for adjusting the shape of the sample U. The shaping member 33 is disposed in the suction direction of the sample U by the suction unit 32, 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.

[0046] After the laser irradiation by the laser light source 13 is stopped, the shaping unit 30 shapes the sample U using the suction unit 32 arranged at a position where the suction unit 32 can suck the sample U. The suction unit 32 is preferably arranged directly above the sample U at a position where its center coincides with the center of the sample U. As a result, the shaping member 33 is arranged directly above the sample U.

[0047] The forming unit 30 reduces the pressure inside the suction unit 32 and sucks the specimen U. The upper part of the sucked specimen U comes into contact with the forming member 33. As a result, the specimen U is pressed against the forming member 33, and the upper part of the specimen U is shaped to match the shape of the forming member 33. If the support member 12 continues to supply gas to the specimen U at this time, the upper part of the specimen U is pressurized by the forming member 33, and the lower part is pressurized by the gas. That is, the specimen U is molded while being sandwiched between the gas from the support member 12 and the forming member 33. Thereafter, the specimen U is cooled to obtain optical glass of the desired thickness and shape.

[0048] Note that, during suction by the suction unit 32, the shaping unit 30 may move the shaping member 33 downward to press the specimen U against the shaping member 33 to adjust the shape. Even in this case, if the support member 12 continues to supply gas to the specimen U, the specimen U is shaped by being sandwiched between the gas from the support member 12 and the shaping member 33. This not only shapes the upper part of the specimen U into the desired shape, but also increases the diameter of the specimen U to a desired size.

[0049] The shaping unit 30 may also press the shaping member 33 against the sample U from above the sample U and bring the lower part of the sample U into contact with the concave surface R of the support member 12, thereby sandwiching and shaping the molten glass between the support member 12 and the shaping member 33. The shapes of the surfaces of the suction unit 32 and the shaping member 33 that come into contact with the sample U may be designed as appropriate.

[0050] <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.

[0051] As in the other embodiments, in this embodiment, gas is sprayed upward from the nozzles 24 (not shown) provided in the flotation section 21 onto the sample U, thereby maintaining the sample U in a floating state. The forming section 30 has a plurality of nozzles 34 (34a-34b) that spray gas onto the sample U from the lateral directions (+X direction, -X direction). The plurality of nozzles 34 spray gas toward the center of the sample U from different directions. As a result, the sample U is pressurized from the lateral directions toward the center, and the thickness increases. The number of nozzles 34 is not limited to two, and is preferably four or more. In addition, it is preferable that the nozzles 34 are arranged so as to surround the sample U, which allows the sample U to be formed uniformly. In addition, it is preferable that the nozzles 34 are spaced at approximately equal intervals.

[0052] In the example shown in Fig. 6, the molding unit 30 is a plurality of holes drilled in the support member 12, and each hole functions as a nozzle 34. The molding unit 30 may be provided on the upper part of the support member 12 as a separate mechanism from the support member 12 that levitates the sample U. When the laser irradiation by the laser light source 13 is stopped, the sample U is maintained in a levitated state by the upward gas injection by the support member 12. Thereafter, the molding unit 30 injects gas toward the sample U from the side, and pressurizes the sample U in a direction from the periphery toward the center. The sample U is then cooled to obtain optical glass of the desired thickness.

[0053] <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 section 21 in this embodiment has a support member that levitates the molten glass and a dividing section 37 that divides the support member. The shaping section 30 in this embodiment has a plurality of shaping members 36 (36a, 36b).

[0054] The support member 12 can be divided into a plurality of members with respect to a plane perpendicular to gravity. The dividing unit 37 divides the support member 12 into a plurality of members. For example, the dividing unit 37 divides the support member 12 by pulling each of the members constituting the support member 12 outward.

[0055] The shaping members 36 (36a and 36b) are molds capable of shaping the heated sample U by applying pressure thereto, and it is preferable that at least a part or all of the members contain stainless steel (SUS), aluminum alloy, quartz, or carbon. The shaping members 36 are a plurality of members arranged around the sample U, and apply pressure to the sample U laterally from different directions toward the center of the sample U.

[0056] The multiple shaping members 36 are located under the support member 12, and are spaced apart from each other before the support member 12 is divided. After the laser irradiation by the laser light source 13 is stopped, the dividing unit 37 divides the support member 12, in which the sample U is 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.

[0057] Each of the forming members 36 moves in a direction toward the center of the sample U to receive the falling sample U and hold the sample U from the side. Thereafter, the forming members 36 move further in a direction toward the center of the sample U, thereby 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) to form the sample U. Thereafter, the sample U is removed from the forming members 36 and cooled, thereby obtaining optical glass of the desired thickness.

[0058] In this embodiment, the forming member 36 may be a container with upright walls. In this case, the forming member 36 applies pressure from the periphery of the sample U by moving the wall in a direction 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 division 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.

[0059] <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 schematic diagram No. 1 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment, and FIG. 8(B) is a schematic diagram No. 2 (cross-sectional view) showing an example of the vicinity of the levitation furnace in the fifth embodiment. The following describes the differences from the first embodiment. The molding section 30 in this embodiment has one or more molding members 35 (35a-35b). The molding section 30 molds the sample U, which has been heated, cooled to room temperature, and then reheated, using the molding members 35.

[0060] 8(A), in glass manufacturing apparatus 10, sample U is suspended above support member 12. At this time, laser light source 13 (not shown) emits laser light L toward sample U to heat sample U. Thereafter, sample U is cooled to room temperature, and optical glass is obtained.

[0061] Next, the molding unit 30 reheats the sample U. The reheating may be performed by holding the sample U with the support member 12 and emitting the laser light L, or may be performed by another heating device. The reheated sample U is placed at 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 equal to or higher than the glass transition point and equal to or lower than the yield point. In other words, the sample U is reheated so that the temperature is equal to or higher than the glass transition point and equal to or lower than the yield point during molding.

[0062] The forming member 35 is a mold capable of forming a shape by applying pressure to the heated sample U. As with the forming member 33 in the above-described embodiment, the forming member 35 preferably contains at least a part or the whole of stainless steel (SUS), an aluminum alloy, quartz, or carbon.

[0063] In the example shown in FIG. 8(B), the forming member 35 is a plurality of members arranged around the sample U, and pressurizes the sample U from different lateral directions toward the center of the sample U. After pressurization, the sample U is cooled again to obtain optical glass of a desired thickness. The configuration of the forming member is not limited to this example. For example, it may be a plurality of claw-shaped members like the forming member 31 in the first embodiment, or it may be a container with upright walls into which the heated sample U is deformed by inserting a viscous material.

[0064] According to this embodiment, the sample U can be molded after the floating process, improving efficiency. In addition, by reheating the sample U to a temperature between the glass transition point and 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 appropriately.

[0065] Sixth embodiment In the above-mentioned first to fifth embodiments, the purpose is 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 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 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 forming member 381, and FIG. 9(C) is a schematic diagram No. 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 forming method of the sample U using the forming member 383.

[0066] In the example shown in FIG. 9(A), the forming member 381 is brought into contact with the sample U suspended by the support member 12 from the gravity direction (-Z direction), and the sample U is sandwiched between the support member 12 and the forming member 381. In other words, the forming member 381 presses the sample U from above to form the sample U. This allows the horizontal diameter of the sample U to be increased. The forming of the sample U by the forming member 381 is preferably performed at a temperature at which the sample U is at or below its deformation point, and more preferably at a temperature at or below its deformation point and above its glass transition point. During forming, the suspending of the sample U by the support member 12 may be stopped, or the sample U may be in a floating state. At this time, the shape of the tip of the forming member 381 on the sample U side may be a desired shape. For example, the forming member 381 may be a lens shape or an aspheric lens shape (not shown) like the forming member 382 in FIG. 9(B).

[0067] An example shown in FIG. 9(C) will be described. The support member 12 is the same as in the fourth embodiment, and therefore the 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 conform to the shape of the forming member 383. In other words, the sample U may be molded to conform to the shape of the forming member 383 by the weight of the sample U itself. 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 to mold it.

[0068] The specimen U is preferably formed by 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.

[0069] <Example> Next, each example will be described, but the present invention is not limited to the following examples in any way.

[0070] <Example 1> First, the oxide raw materials were weighed to have 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.

[0071] 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 material was then melted by irradiating it from above with a carbon dioxide laser while injecting air. The molten raw material became approximately spherical due to its own surface tension, and was suspended by the gas pressure. When the raw material was completely melted, the laser output was shut off to cool it, and a sample U was obtained. The diameter φ and thickness t of the sample U at this point were measured.

[0072] 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.

[0073] <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.

[0074] Table 1 shows the composition of the raw materials in each example.

[0075] [Table 1]

[0076] <Evaluation> Fig. 10 is a diagram showing the measurement results of the sample U obtained as a result of each example. According to Fig. 9, it was confirmed that the thickness t of the sample U increased in each example. In addition, devitrification was not confirmed in any of the glasses of each example. The thickness of the glass after molding is preferably 7.0 mm or more, more preferably 7.5 mm or more, and even more preferably 7.7 mm or more.

[0077] From the above, it was confirmed that the glass manufacturing apparatus 10 of each Example was capable of stably manufacturing optical glass having a desired diameter and thickness.

[0078] <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 an optical system. The optical system according to the present embodiment can be suitably used as an interchangeable lens for a camera including the optical system. As the configuration of such optical elements, optical lenses, and interchangeable lenses for a camera, known ones can be adopted. Furthermore, the optical system according to the present embodiment can be suitably used as an optical device including the optical system. Examples of optical devices including such an optical system include, but are not limited to, imaging devices such as interchangeable lens cameras and non-interchangeable lens cameras, and optical microscopes. An example of these will be described below.

[0079] (Imaging device) FIG. 11 is a perspective view of an example in which the optical device according to each embodiment is used as an imaging device.

[0080] 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 is imaged on a sensor chip (solid-state imaging element) 104 of a multi-chip module 106 arranged 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.

[0081] FIG. 12 is a front view of another example in which the optical device according to each embodiment is used as an imaging device, and FIG. 13 is a rear view of the imaging device.

[0082] The imaging device CAM is a so-called digital still camera (lens non-interchangeable 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 a subject (object) is collected by the photographing lens WL and imaged on an imaging element arranged on an image plane. The subject image imaged on the imaging element is displayed on a liquid crystal monitor M arranged behind the imaging device CAM. After the photographer decides the composition of the subject image while looking at the liquid crystal monitor M, he presses down the release button B1 to capture the subject image with the imaging element and record and save it in a memory (not shown). The imaging device CAM is provided with an auxiliary light emitting unit EF that emits auxiliary light when the subject is dark, a function button B2 used for setting various conditions of the imaging device CAM, and the like.

[0083] Optical systems used in such digital cameras and the like are required to have higher resolution, lighter weight, and smaller size. In order 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 above-mentioned imaging device, but also includes, for example, a projector. The optical element is also not limited to a lens, but also includes, for example, a prism.

[0084] (Multiphoton Microscopy) FIG. 14 is a block diagram showing an example in which the optical device according to each embodiment is a multiphoton microscope.

[0085] 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.

[0086] The pulsed laser device 201 emits ultrashort pulsed light having, for example, a near-infrared wavelength (about 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.

[0087] The pulse splitting device 202 splits the ultrashort pulse light, increases the repetition frequency of the ultrashort pulse light, and emits it.

[0088] The beam adjusting unit 203 has a function of adjusting 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 of adjusting 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) of imparting inverse group velocity dispersion to the ultrashort pulsed light in order to correct the pulse width of the ultrashort pulsed light being broadened due to group velocity dispersion while passing through the optical system.

[0089] 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 on the observation surface of the sample S by using a scanning means (not shown).

[0090] 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") having a wavelength shorter than that of the ultrashort pulsed light, which is an infrared wavelength.

[0091] 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.

[0092] The observation light reflected by the dichroic mirror 205 enters the fluorescence detection unit 207. The fluorescence detection unit 207 is composed of, 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.

[0093] On the other hand, the observation light that passes 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 to the focal position of the objective lens 206, passes through an imaging lens 210, and enters the fluorescence detection unit 211.

[0094] The fluorescence detection unit 211 is composed of, 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.

[0095] 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 .

[0096] Moreover, the 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 composed of, for example, a barrier filter, a PMT, etc., receives the observation light reflected by the dichroic mirror 212, and outputs an electrical signal according to the amount of light. Moreover, 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.

[0097] The electrical signals output from the fluorescence detection units 207, 211, and 213, respectively, are input, for example, to a computer (not shown), and the computer can generate an observation image based on the input electrical signals, display the generated observation image, and store data of the observation image.

[0098] <Cemented lens> FIG. 15 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 constituting the cemented lens may be referred to as "lens elements" as described above in order to clarify that they are elements of the cemented lens.

[0099] The cemented lens according to each embodiment is useful from the viewpoint of chromatic aberration correction, and can be suitably used in the above-mentioned optical elements, optical systems, optical devices, and the like. The optical system including the cemented lens can be particularly suitably used in interchangeable lenses for cameras, optical devices, and the like. Note that, in the above-mentioned embodiment, the cemented lens using two lens elements has been described, but the present invention is not limited thereto, and a cemented lens using three or more lens elements may 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]

[0100] 1...imaging device (lens-interchangeable 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 section, L: laser light, 22...control section, 23...calculation section, 24...nozzle, R: concave surface, U: sample, W1...first surface, W2...second surface, 30...shaping section, 31a, 31b, 31c, 31d, 31e, 31f, 31g, 31h, 33, 35, 35a, 35b, 36a, 36b, 381, 382, ​​383...shaping member, 32...suction section, 34...nozzle, 37...splitting section, 101...camera body, 102...lens barrel, 103...lens, 104...sensor chip, 105...glass substrate, 106...multi-chip module, CAM...imaging device (lens non-interchangeable camera), WL...taking lens, M...liquid crystal monitor, EF...auxiliary light emitting unit, B1...release button, B2...function button, 2...multiphoton microscope, 201...pulse laser device, 202...pulse splitting device, 203...beam adjustment unit, 204, 205, 212...dichroic mirror, 206...objective lens, 207, 211, 213...fluorescence detection unit, 208...condensing lens, 209...pinhole, 210...imaging lens, S...sample, 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 process of reducing the temperature of a non-contact supported glass raw material, comprising: a heating unit for heating the glass raw material; a forming unit for forming the molten glass raw material during a period when the heating of the glass raw material by the heating unit stops and the temperature of the molten glass raw material decreases.

2. The glass manufacturing apparatus according to claim 1, further comprising a control unit for controlling the forming unit, wherein the control unit controls the forming unit to form the molten glass raw material based on conditions using predetermined characteristics of the glass.

3. The glass manufacturing apparatus according to claim 2, wherein the control unit has a calculation unit for calculating a timing for forming the molten glass raw material based on the conditions, and controls the forming unit to form the molten glass raw material at the timing calculated by the calculation unit.

4. The glass manufacturing apparatus according to claim 2, wherein the control unit has a measurement unit for measuring the temperature of the molten glass raw material, determines a timing for forming the molten glass raw material based on the measurement result of the measurement unit and the conditions, and controls the forming unit to form the molten glass raw material at the timing.

5. The glass manufacturing apparatus according to any one of claims 2 to 4, wherein the predetermined characteristic is the temperature of the yield point of the glass.

6. The condition is that the temperature of the molten glass raw material is a temperature equal to or lower than the yield point of the glass, and the control unit controls the forming unit so that the forming of the molten glass raw material by the forming unit is performed in a state satisfying the condition.

7. The glass manufacturing apparatus according to claim 6, wherein the predetermined characteristic is the glass transition point of the glass.

8. The condition is that the temperature of the molten glass raw material is a temperature equal to or lower than the yield point of the glass and equal to or higher than the glass transition point of the glass, and the control unit controls the forming unit so that the forming of the molten glass raw material by the forming unit is performed in a state satisfying the condition.

9. The forming unit has a forming member for forming the shape of the glass raw material in the molten state, and forms the molten glass raw material by pressing the forming member against the molten glass raw material. The glass manufacturing apparatus according to any one of claims 1 to 4.

10. The forming unit has a plurality of the forming members, and forms the shape of the molten glass raw material by pressing the plurality of the forming members against the molten glass raw material. The glass manufacturing apparatus according to claim 9.

11. The forming unit has 4 or more of the forming members, and forms the shape of the molten glass raw material by driving the plurality of the forming members in a predetermined plane. The glass manufacturing apparatus according to claim 10.

12. The forming member has an arc shape. The glass manufacturing apparatus according to claim 9.

13. The forming unit presses the forming member against the molten glass raw material from above the molten glass raw material to form the molten glass raw material. The glass manufacturing apparatus according to claim 9.

14. It has a support part capable of supporting the glass raw material in contact and non-contact. The forming unit presses the forming member from above the molten glass raw material, and forms the molten glass raw material by sandwiching the molten glass raw material between the support part and the forming member. The glass manufacturing apparatus according to claim 13.

15. The forming unit has a suction part for sucking the molten glass raw material, and forms the molten glass raw material by sucking the molten glass raw material by the suction part. The glass manufacturing apparatus according to any one of claims 1 to 4.

16. The forming unit is cylindrical. The glass manufacturing apparatus according to claim 15.

17. The forming unit has a suction part for sucking the molten glass raw material and a forming member for forming the molten glass raw material. By sucking the molten glass raw material by the suction part and pressing the forming member against the molten glass raw material, the molten glass raw material is formed. The glass manufacturing apparatus according to any one of claims 1 to 4.

18. The suction part is provided so as to surround the forming member with respect to a plane orthogonal to the gravitational direction. The glass manufacturing apparatus according to claim 17.

19. The shaping part has a nozzle for spraying gas onto the glass raw material in the molten state supported without contact, and shapes the glass raw material in the molten state by the gas jetted from the nozzle. The glass manufacturing apparatus according to any one of claims 1 to 4.

20. It has a support part capable of supporting the glass raw material in contact and without contact. The support part has a support member for supporting the glass raw material in the molten state without contact, and a dividing part for dividing the support member with respect to a plane orthogonal to gravity. The dividing part divides the support member that supports the glass raw material in the molten state without contact with respect to the plane. The shaping part has a plurality of shaping members for shaping the shape of the glass raw material in the molten state, and shapes the glass raw material in the molten state by pressing the shaping members against the glass raw material in the molten state falling from the support member from at least two directions. The glass manufacturing apparatus according to any one of claims 1 to 4.

21. It has a support part capable of supporting the glass raw material in contact and without contact. The support part has a support member for supporting the glass raw material in the molten state without contact, and a dividing part for dividing the support member with respect to a plane orthogonal to gravity. The dividing part divides the support member that supports the glass raw material in the molten state without contact with respect to the plane. The shaping part has a plurality of shaping members for shaping the shape of the glass raw material in the molten state, and shapes the glass raw material in the molten state by putting the glass raw material in the molten state that has fallen from the support member into the shaping members. The glass manufacturing apparatus according to any one of claims 1 to 4.

22. It has a support part capable of supporting the glass raw material in contact and without contact. The support part has a jet outlet from which gas is jetted, and non - contact supports the glass raw material by the gas jetted from the jet outlet. The glass manufacturing apparatus according to any one of claims 1 to 4.

23. The heating part heats the glass raw material supported without contact. The glass manufacturing apparatus according to any one of claims 1 to 4.

24. The melting point of the shaping member is 500 degrees or more. The glass manufacturing apparatus according to claim 9.

25. The shaping member is an aluminum alloy. The glass manufacturing apparatus according to claim 9.

26. It has a support part capable of supporting the glass raw material in contact and without contact. The manufacturing apparatus for glass according to any one of claims 1 to 4, wherein the support part supports the glass raw material non - contact by static electricity.

27. The heating part heats the glass raw material by irradiating laser light to the glass raw material, The manufacturing apparatus for glass according to any one of claims 1 to 4, wherein the forming part forms the glass raw material in a molten state which is not irradiated with the laser light.

28. A method for manufacturing glass, which manufactures glass using the manufacturing apparatus for glass according to any one of claims 1 to 4.

29. A method for manufacturing glass, which manufactures glass through a step of lowering the temperature of a non - contact supported glass raw material, including a melting step of heating and melting the glass raw material by a heating part, and a forming step of forming the glass raw material in a molten state while the temperature of the glass raw material in a molten state is decreasing. A method for manufacturing glass.

30. including a stopping step of stopping the heating of the glass raw material by the heating part, The forming step is performed after the stopping step. The method for manufacturing glass according to claim 29.

31. In the forming step, the glass raw material in a molten state is formed at a temperature equal to or higher than the glass transition point and lower than the yield point of the glass. The method for manufacturing glass according to claim 29 or 30.

32. A method for manufacturing glass, which manufactures glass through a step of lowering the temperature of a non - contact supported glass raw material, including a melting step of heating and melting the glass raw material, a cooling step of lowering the temperature of the glass raw material in a molten state to obtain the glass, a reheating step of heating and melting the glass, and a forming step of forming the melt of the glass while the temperature of the melted glass is decreasing. A method for manufacturing glass including these steps.

33. In the forming step, the melt of the glass is formed at a temperature equal to or higher than the glass transition point and lower than the yield point of the glass. The method for manufacturing glass according to claim 32.

34. The forming part forms the glass raw material in a molten state at least during a part of a period in which the gas jets out from the jet outlet and is sprayed onto the glass raw material in a molten state on the support part. The manufacturing apparatus for glass according to claim 22.

Images