KR102103864B1 - Apparatus and Method for Producing Preforms of Lens - Google Patents

Abstract

Disclosed is an apparatus and method for manufacturing a preform of a lens.
According to an aspect of the present embodiment, in an apparatus for producing a preform of a lens manufactured by mold molding, a light source for irradiating light for heating a lens disk and at least one through hole in which the lens disk is to be arranged are provided. It provides a preform production apparatus, characterized in that it comprises a top plate for fixing the middle plate and disposed on the upper end of the middle plate.

Description

Apparatus and Method for Producing Preforms of Lens

The present invention relates to an apparatus and method for manufacturing a preform of a lens using a lens disk.

The contents described in this section merely provide background information for this embodiment, and do not constitute a prior art.

Lenses are essential elements in various optical fields. As a material constituting such a lens, a material that has recently been spotlighted is a chalcogenide-based material. The chalcogenide-based material is rich in reserves and relatively easy to process, making it a popular choice for lenses.

Chalcogenide-based materials used to manufacture lenses include germanium (Ge), antimony (Sb), and selenium (Se). At this time, since germanium has a property of being oxidized when it encounters oxygen, in manufacturing a lens from a chalcogenide-based material, a manufacturing process is performed under vacuum.

The lens manufacturing process using the newly developed vacuum molding is as follows. In a vacuum state, a lens disc is charged between an upper mold and a lower mold, and the lens disc is pressed using the molds to manufacture a lens.

Therefore, the conventional lens manufacturing process has a disadvantage in that the surface of the manufactured lens is deteriorated because only the molding is performed. In addition, since the shape of the mold has a side in which it is difficult to fully implement the unevenness, a lens produced by a conventional lens manufacturing process may not have a desired intact shape.

In addition, in the lens manufacturing process, the environment in which the process is performed or the temperature of the lens disk is a very important factor. Even if the temperature is only different, it greatly affects the performance of the lens. As described above, the conventional lens manufacturing process proceeds in a vacuum state due to the nature of the chalcogenide material, but in the vacuum state, heat transfer efficiency is significantly reduced. Due to this problem, the conventional lens manufacturing process has a high probability that the temperature of the lens disk does not rise to a temperature suitable for molding, even if sufficient heat is provided for molding, and performance is significantly lowered (for example, roughness of the lens) Is worse, curvature is not constant, etc.).

One embodiment of the present invention has an object to provide an apparatus and method for manufacturing a preform of a lens using a lens disk before manufacturing the lens.

One embodiment of the present invention is to provide an apparatus and method for manufacturing a preform having a uniform heat distribution and an appropriate height (Sag).

In addition, one embodiment of the present invention, it is an object to provide an apparatus and method for mass production of a plurality of preforms having a constant performance by uniformly heating the lens disk.

According to an aspect of the present invention, in an apparatus for producing a preform of a lens manufactured by mold molding, a light source for irradiating light for heating a lens disk and at least one through hole in which the lens disk is to be arranged are provided. It provides a preform production apparatus, characterized in that it comprises a top plate for fixing the middle plate and disposed on the upper end of the middle plate.

According to an aspect of the present invention, the light source is characterized by irradiating light in the ultraviolet wavelength band.

According to an aspect of the present invention, the upper plate is characterized in that it is made of a light-transmitting material so that the light irradiated by the light source can be transmitted to the lens disk disposed on the middle plate.

According to an aspect of the present invention, the through-hole is implemented as a first through-hole having a width and height equal to or greater than the width and height of the lens disc and a second through-hole having a width narrower than the width of the lens disc. It is characterized by.

According to one aspect of the invention, the middle plate is characterized in that it comprises a first middle plate having the first through hole and a second middle plate having the second through hole.

According to an aspect of the present invention, it is arranged on the lower end of the middle plate to fix the middle plate, and further comprising a lower plate having a through hole having a narrower width than the through hole.

According to an aspect of the present invention, in a method of producing a preform of a lens by a preform production device of a lens manufactured by mold molding, a first arrangement process in which a lens disk is disposed on a middle plate having one or more through holes And a second arrangement process in which an upper plate is disposed at an upper end portion of the middle plate to fix the middle plate, and a light irradiation process for irradiating light for heating the lens disc.

According to an aspect of the present invention, the light irradiation process is characterized by irradiating light in the ultraviolet wavelength band.

According to an aspect of the present invention, the upper plate is characterized in that it is made of a light-transmitting material so that the light irradiated by the light source can be transmitted to the lens disk disposed on the middle plate.

According to an aspect of the present invention, the through-hole is implemented as a first through-hole having a width and height equal to or greater than the width and height of the lens disc and a second through-hole having a width narrower than the width of the lens disc. It is characterized by.

According to one aspect of the invention, the middle plate is characterized in that it comprises a first middle plate having the first through hole and a second middle plate having the second through hole.

According to an aspect of the present invention, in the apparatus for producing a preform (Preform) of a lens manufactured by mold molding, the middle plate is disposed on the upper end of the middle plate and at least one through-hole to which the lens disk is disposed It provides a preform production apparatus, characterized in that it comprises a top plate having a heat source (열 源) for transferring heat to the fixed, and the lens disk disposed on the middle plate.

According to an aspect of the present invention, the through-hole has a width equal to or greater than the width of the lens disk, and a first through-hole having a height higher than that of the lens disk and a width having a width narrower than that of the lens disk. It is characterized by being implemented with 2 through holes.

According to an aspect of the present invention, in a method of producing a preform of a lens by a preform production device of a lens manufactured by mold molding, a first arrangement process in which a lens disk is disposed on a middle plate having one or more through holes And a second arrangement process in which a top plate including a heat source is disposed at an upper end of the middle plate to fix the middle plate, and a lens disc disposed on the middle plate is heated by a heat source in the top plate disposed at the top of the middle plate. It provides a preform production method characterized in that it comprises a heating process.

As described above, according to one aspect of the present invention, there is an advantage of improving the thermal uniformity of the lens disk by manufacturing a preform of the lens using a lens disk before manufacturing the lens.

According to an aspect of the present invention, there is an advantage that can produce a preform having excellent roughness, uniform heat distribution and a suitable height (Sag).

In addition, according to an aspect of the present invention, there is an advantage in that a plurality of preforms having uniform performance can be mass-produced by uniformly heating the lens disc.

1 is a view showing the configuration of a lens manufacturing system according to an embodiment of the present invention.
2 is a configuration diagram showing the configuration of a preform manufacturing apparatus according to a first embodiment of the present invention.
3 is a cross-sectional view showing a cross section of the upper plate, the middle plate and the lower plate in the preform manufacturing apparatus according to the first embodiment of the present invention.
4 is a plan view of an upper plate, a middle plate, and a lower plate in a preform manufacturing apparatus according to a first embodiment of the present invention.
5 is a view showing a state in which the lens disk according to the first embodiment of the present invention is disposed in a preform manufacturing apparatus.
6 is a view showing a state in which the lens disk is heated using the light source according to the first embodiment of the present invention.
7 is a view showing a state in which the lens disk is bent according to the first embodiment of the present invention.
8 is a flowchart illustrating a method for manufacturing a preform by a preform manufacturing apparatus according to a first embodiment of the present invention.
9 is a configuration diagram showing the configuration of a preform manufacturing apparatus according to a second embodiment of the present invention.
10 is a plan view of a top plate and a middle plate in a preform manufacturing apparatus according to a second embodiment of the present invention.
11 is a view showing a state in which the lens disk according to the second embodiment of the present invention is disposed in a preform manufacturing apparatus.
12 is a view showing a state in which the top plate according to the second embodiment of the present invention heats the lens disk.
13 is a view showing a state in which the lens disk is bent according to the second embodiment of the present invention.
14 is a flow chart showing a method of manufacturing a preform by a preform manufacturing apparatus according to a second embodiment of the present invention.
15 is a view showing a preform of a lens manufactured by a preform manufacturing apparatus according to a first or second embodiment of the present invention.
16 is a view showing the configuration of a lens manufacturing apparatus according to an embodiment of the present invention.
17 is a view showing a state in which a lens manufacturing apparatus according to an embodiment of the present invention creates a vacuum state in which a preform of a lens is disposed.
18 is a view showing a state in which the lens manufacturing apparatus according to an embodiment of the present invention heats the preform of the lens.
19 is a view showing a state in which the lens manufacturing apparatus according to an embodiment of the present invention presses the preform of the lens.
20 is a view showing a state in which the lens manufacturing apparatus according to an embodiment of the present invention is cooled.
21 is a view showing a lens manufactured by a lens manufacturing apparatus according to an embodiment of the present invention.
22 is a view showing the configuration of an infrared lens manufactured according to an embodiment of the present invention.
23 is a graph showing distortion aberration of an infrared lens according to a third embodiment of the present invention.
24 is a graph showing MTF characteristics of an infrared lens according to a third embodiment of the present invention.
25 is a diagram showing a configuration and a Sag value of a first lens according to a third embodiment of the present invention.
26 is a graph illustrating distortion aberration of an infrared lens according to a fourth embodiment of the present invention.
27 is a graph showing MTF characteristics of an infrared lens according to a fourth embodiment of the present invention.
28 is a diagram showing a configuration and a Sag value of a first lens according to a fourth embodiment of the present invention.
29A to 29D show a comparison of a 2 mm thick transmission spectrum of germanium-antimony-selenium ternary glass and germanium-gallium-antimony-selenium tetracomponent glass (chalcogenide glass composition according to an embodiment of the present application). It is a graph.
30 is a graph comparing Vickers hardness of the germanium-antimony-selenium ternary glass and the germanium-gallium-antimony-selenium tetracomponent glass (chalcozinide glass composition according to an embodiment of the present application).
FIG. 31 is a graph comparing thermal expansion coefficients of a germanium-antimony-selenium ternary glass and a germanium-gallium-antimony-selenium four-component glass (chalcozinide glass composition according to an embodiment of the present application).
32 and 33 are graphs comparing glass transition temperatures and softening points of germanium-antimony-selenium ternary glass and germanium-gallium-antimony-selenium quadrant glass (chalcogenide glass composition according to an embodiment of the present application) to be.

The present invention can be applied to various changes and can have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals are used for similar components.

Terms such as first, second, A, and B can be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from other components. For example, the first component may be referred to as a second component without departing from the scope of the present invention, and similarly, the second component may be referred to as a first component. The term and / or includes a combination of a plurality of related described items or any one of a plurality of related described items.

When an element is said to be "connected" or "connected" to another component, it is understood that other components may be directly connected to or connected to the other component, but other components may exist in the middle. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

Terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. It should be understood that terms such as “include” or “have” in the present application do not preclude the existence or addition possibility of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification. .

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains.

Terms such as those defined in a commonly used dictionary should be interpreted as having meanings consistent with meanings in the context of related technologies, and should not be interpreted as ideal or excessively formal meanings unless explicitly defined in the present application. Does not.

In addition, each configuration, process, process or method included in each embodiment of the present invention may be shared within a technically inconsistent range.

1 is a view showing the configuration of a lens manufacturing system according to an embodiment of the present invention.

Referring to FIG. 1, a lens manufacturing system 100 according to an embodiment of the present invention includes a preform manufacturing apparatus 110 and a lens manufacturing apparatus 120.

The preform manufacturing apparatus 110 manufactures a lens disc as a preform of a lens. The lens disk is directly introduced into the lens manufacturing apparatus 120, and the lens is not manufactured, but the lens disk passes through the preform manufacturing apparatus 110 and is manufactured as a preform of the lens. When the preform of the lens is manufactured and introduced into the lens manufacturing apparatus, the roughness of the surface of the manufactured lens is excellent (smooth) compared to the case where the lens disc is directly introduced, and the transferability is increased, so that the curvature of the lens is constant. There is this. The preform manufacturing apparatus 110 and the preform manufacturing apparatus 110 will be described in detail with reference to FIGS. 2 to 15 for a process of manufacturing a lens disc as a preform of a lens.

Here, the lens disk or the preform of the lens is made of a material of the Chalcogenide series. Chalcogenide-based materials used to manufacture lenses include germanium (Ge), antimony (Sb), and selenium (Se). At this time, since germanium has a property of being oxidized when it encounters oxygen, the preform manufacturing apparatus 110 may have a vacuum environment. However, implementing a complete vacuum environment may be inefficient in terms of cost or structure, so the preform manufacturing apparatus 110 can manufacture a preform of a lens in a nitrogen atmosphere (in Nitrogen) where little oxygen is present. have.

The lens manufacturing apparatus 120 manufactures a preform of a lens manufactured by the preform manufacturing apparatus 110 as a lens. A preform of a lens is manufactured as a lens by pressing a preform of the lens using an upper core and a lower core having complementary lens shapes. A detailed description of the lens manufacturing apparatus 120 and the process in which the lens manufacturing apparatus 120 manufactures a lens disk as a preform of a lens will be described with reference to FIGS. 16 to 21.

The lens manufacturing apparatus 120, like the preform manufacturing apparatus 110, manufactures a preform of a lens made of a chalcogenide-based material with a lens, and must suppress the reaction between oxygen and the preform of the lens at a softening point or higher. , Preferably, the lens is manufactured in an environment where there is little oxygen, such as a vacuum environment or a nitrogen atmosphere.

2 is a configuration diagram showing the configuration of a preform manufacturing apparatus according to a first embodiment of the present invention.

Referring to FIG. 2, the preform manufacturing apparatus 110 according to the first embodiment of the present invention includes a light source 210, an upper plate 220, a middle plate 230, a lower plate 240, and a decompression unit 250. .

The light source 210 irradiates light for heating the lens disk disposed on the middle plate 230. The light source 210 irradiates light in an ultraviolet wavelength band such as a halogen lamp. The lens disk is heated by receiving light emitted by the light source 210. Since the lens disk can be heated as long as light arrives, the efficiency for heating the lens disk is better than using a separate heat source. Since the method of heating the lens disk using a heat source has a difference in heat transfer rate between a portion where the heat source is disposed and a portion where the heat source is disposed, the degree to which the lens disk disposed in the corresponding portion is heated differs. On the other hand, in the method of heating the lens disk using light, since there is no obstacle in the optical path, light reaches the lens disk evenly. Accordingly, each lens disk can be evenly heated. The light source 210 needs only to be disposed to be able to uniformly irradiate light to each lens disk. Therefore, the light source 210 does not need to be arranged so as to fill all of the area of the top plate 220, but may be arranged at regular intervals.

The light source 210 is mainly disposed on the top of the top plate 220, and irradiates light with a lens disk. However, the present invention is not necessarily limited thereto, and the light source 210 is also disposed at the lower portion of the lower plate 240 to irradiate light with a lens disc. The lower plate 240 includes a through hole 245 , Light irradiated by the light source 210 disposed under the lower plate 240 may be irradiated to the lens disk. As described above, since the light sources 210 may be disposed at regular intervals, in particular, the light sources 210 to be disposed under the lower plate 240 may be arranged at regular intervals at positions that do not affect preform manufacturing. You can. The preform manufacturing apparatus 110 has an advantage of using the light source 210 without using an excessive heat source to heat the lens disc more efficiently at a low cost.

The upper plate 220 is disposed on the upper portion of the middle plate 230 to fix the middle plate 230. The upper plate 220 may have an area that is at least equal to or larger than the area of the middle plate 230, and is disposed on the upper portion of the middle plate 230 to fix the middle plate 230.

The top plate 220 may be made of a light-transmitting material in the ultraviolet wavelength band. As described above, the light source 210 irradiates light in the ultraviolet wavelength band from the upper portion of the upper plate 220 to the lens disc disposed on the middle plate 230. In order for the lens disk to be irradiated and heated, light irradiated from the light source 210 must pass through the top plate 220. Therefore, the upper plate 220 may be made of a light transmissive material in the ultraviolet wavelength band.

The middle plate 230 has a through hole 235, and a lens disk is disposed. The middle plate 230 may include one or more through-holes 235, and in particular, may have a plurality of through-holes 235 to manufacture a large number of preforms of lenses at a time. The lens disk is disposed in the through hole 235. The middle plate 230 arranges a lens disk in the through hole 235 so that when the lens disk is heated by light, it can be bent downward by a certain height (Sag) by the darkening part 250 and gravity.

The lower plate 240 is disposed under the middle plate 230 to fix the middle plate 230 together, and has a through hole 245 to allow the suction force of the decompression unit 250 to be transmitted to the lens disk. The through hole 245 is provided on the lower plate 240 in the same position as the through hole 235 formed on the middle plate 230. That is, when viewed from above, the through hole 245 is disposed on the lower plate 240 such that the center of the through hole 245 and the center of the through hole 235 have concentric circles having the same coordinates.

The decompression unit 250 applies a force downward to the lens disk disposed on the middle plate 230. The decompression unit 250 applies a force downward to the lens disk disposed on the middle plate 230 using various methods such as inhaling air. Since the middle plate 230 and the lower plate 240 include through holes 235 and 245, respectively, the pressure reducing unit 250 may apply a force downward to the lens disk. The pressure reducing unit 250 applies a force to the lower portion of the lens disc, so that the lens disc warms up to a lower temperature and then smoothly bends.

3 is a cross-sectional view showing a cross section of the upper plate, the middle plate and the lower plate in the preform manufacturing apparatus according to the first embodiment of the present invention, Figure 4 is a top plate, a middle plate and a lower plate in the preform manufacturing apparatus according to the first embodiment of the present invention It is a top view.

The upper plate 220 is disposed on the upper portion of the middle plate 230

The middle plate 230 includes a through hole 235 in which a lens disk is to be disposed. The through-hole 235 is the first through-hole 310 and the first through-hole 310 having the same width or height as the width (width) and height of the lens disc and the width (width) of the lens disc. And a second through hole 315 having a narrower width (width). Since the width (width) of the second through hole 315 is narrower than the width (width) of the first through hole 310 and the lens disk, the lens disk is disposed in the first through hole 310 and the first through hole ( 310).

The width (width) of the second through hole 315 may be formed to be wider than the effective diameter of the portion protruding from the preform of the lens. When the width (width) of the second through hole 315 is narrower than the effective diameter, a portion in which the preform of the lens bends downward and protrudes may contact the middle plate 230. When the preform of the bent lens in the heated state contacts the middle plate 230, there is a fear that the surface roughness of the resulting lens is deteriorated and the curvature of the lens is also inconsistent. The width (width) of the second through hole 315 is formed to be wider than the effective diameter of the portion protruding from the preform of the lens, so that the preform of the lens, in particular, the preform of the heated and curved lens does not contact the middle plate 230 The above-mentioned problems can be prevented.

The middle plate 230 includes a first middle plate 234 having a first through hole 310 disposed at predetermined intervals and a second middle plate 238 having a second through hole 315 disposed at predetermined intervals. It may include. The middle plate 230 should be provided with both the first through hole 310 and the second through hole 315, and it may not be easy to form through holes having different widths at once. Therefore, the middle plate 230 is easily included by including each of the first middle plate 234 having the first through hole 310 and the second middle plate 238 having the second through hole 315 in a combined form. Through holes having different widths may be provided.

The lower plate 240 is disposed under the middle plate 230.

The lower plate 240 is disposed at the same position as the through hole 235 of the middle plate, and includes a through hole 320 having a narrower diameter than the through holes 310 and 315. Since the lower plate 240 includes a through hole 320 having a smaller diameter than the through holes 310 and 315 and an inclined surface 320 at a certain angle, the central portion of the preform of the heated and curved lens has a smoother curvature It can be more protruding. Conventionally, a conventional lens manufacturing apparatus for manufacturing a lens by molding a lens disk without manufacturing a preform produces a lens by pressing a lens disk using a mold to manufacture the lens. At this time, when the mold presses the lens disc, pressure is usually transmitted to the outer portion of the mold, while pressure is relatively low to the central portion of the mold. In addition, there may be gas or residues that may be generated in the molding process in the center of the mold. Accordingly, the lens manufactured by the conventional lens manufacturing apparatus has a problem in that the shape of the mold is not completely transmitted (low transferability) in the central portion, and thus does not have a constant curvature. However, as described above, the preform manufacturing apparatus 110 uses the structure of the lower plate 240 and the depressurizing portion 250 so that the central portion of the preform protrudes more smoothly, so the pressure relative to the central portion of the mold of the lens manufacturing apparatus is relatively high. Even if it is transmitted less, it has an advantage that a lens having a constant curvature can be manufactured.

Referring to FIG. 4, the first through hole 310, the second through hole 315 of the middle plate 230, and the through hole 245 of the lower plate are disposed at the same position. That is, each through hole center is arranged to have a concentric shape having the same coordinates. Accordingly, it is possible to bend downward from the center of the lens disk disposed on the middle plate 230.

In addition, the middle plate 230 may further include a groove 410 connecting the through holes 235 of the middle plate 230 to each other. The preform manufacturing apparatus 110 manufactures a preform, and gas may be generated in the manufacturing process. When such gas is not discharged from the middle plate 230, in particular, the through hole 235, the height (Sag) of the preform of each lens manufactured by the gas becomes inconsistent, and the surface roughness of the lens becomes worse. Occurs. To solve this problem, the middle plate 230 further includes a groove 410 connecting the through holes 235 of the middle plate 230 to each other, and gas generated in the manufacturing process is formed from the through holes 235. 410). Accordingly, there is an advantage in that the preform of the lens to be manufactured and the performance of the lens manufactured therefrom are excellent.

5 is a view showing a state in which the lens disk according to the first embodiment of the present invention is disposed in a preform manufacturing apparatus.

For the preform production of the lens, a lens disk 510 is disposed in the preform production apparatus 110. The lens disk 510 is disposed in the through hole 235 provided in the middle plate 310 in the preform manufacturing apparatus 110. As described above, the material of the lens disk 510 may be a chalcogenide-based material, and in the preform manufacturing apparatus 110 due to material characteristics

6 is a view showing a state in which the lens disk is heated using the light source according to the first embodiment of the present invention.

The light source 210 disposed on the top of the top plate 220 irradiates light, thereby heating the lens disc 510. As described above, instead of using a separate heat source, the light source 210 irradiates light in the ultraviolet wavelength band to heat the lens disk 510. Although only the light source 210 disposed on the upper portion of the upper plate 220 is illustrated in FIG. 6, the light source 210 is also disposed on the lower portion of the lower plate 240 to irradiate light to the lens disk 510. When the light source 210 is additionally disposed, there is an advantage that each lens disk 510 can be heated more uniformly and quickly.

7 is a view showing a state in which the lens disk is bent according to the first embodiment of the present invention.

When the lens disk 510 is heated, since it is disposed on the through hole 235 of the middle plate 230, it is naturally bent downward by gravity. However, when the heated lens disk 510 is bent only by gravity, there is a possibility that it cannot bend to an effective height (Sag), and a long time is consumed even if it is extended to an effective height (Sag). Accordingly, the preform manufacturing apparatus 110 applies the suction force to the lower portion of the lens disc 510 using the depressurizing portion 250, thereby allowing the lens disc 510 to bend more smoothly to the lower portion. As described above, the lens disk 510 can be fully bent without coming into contact with the middle plate 230, and the central portion can be projected more smoothly.

The preform of the lens manufactured as described above is taken out and put into the lens manufacturing apparatus 120 to be used for manufacturing the lens.

8 is a flowchart illustrating a method for manufacturing a preform by a preform manufacturing apparatus according to a first embodiment of the present invention. Since it was described in detail with reference to FIGS. 2 to 7, a detailed description of a method of manufacturing a preform will be omitted.

The lens disk 510 is disposed on the middle plate 230 having one or more through holes (S810).

The preform manufacturing apparatus 110 places the upper plate 220 on the upper end of the middle plate and the lower plate 240 on the lower end of the middle plate 230 to fix the middle plate 230 (S820).

The preform manufacturing apparatus 110 irradiates light for heating the lens disk 510 using the light source 210 (S830).

The preform manufacturing apparatus 110 additionally unfolds the lens disk 510 to the lower end using the decompression unit 250 (S840).

9 is a configuration diagram showing the configuration of a preform manufacturing apparatus according to a second embodiment of the present invention.

Referring to FIG. 9, the preform manufacturing apparatus 110 according to the second embodiment of the present invention includes an upper plate 910, a middle plate 920, and a pressure reducing unit 930.

The upper plate 910 is disposed above the middle plate 920 to fix the middle plate 920. The top plate 910 may have an area that is at least equal to or larger than the area of the middle plate 920, and is disposed on the top of the middle plate 920 to fix the middle plate 920.

The top plate 910 includes a heat source (熱 援, not shown) therein, and heats the lens disc disposed on the middle plate 920 from the top of the middle plate 920. The preform manufacturing apparatus 110 according to the second embodiment heats the lens disk using the top plate 910 including a heat source instead of a separate light source.

The middle plate 920 is provided with a through hole 925, and a lens disk is disposed. The middle plate 920 may include one or more through-holes 925, and particularly, may have a plurality of through-holes 925 to manufacture a large amount of preforms of lenses at a time. The lens disk is disposed in the through hole 925. The middle plate 920 arranges the lens disk in the through hole 925, so that when the lens disk is heated by light, it can be bent downward by a certain height (Sag) by the darkening part 930 and gravity.

The pressure reducing unit 930 applies a force downward to the lens disk disposed on the middle plate 920. The decompression unit 930 applies a force to the lower portion of the lens disk disposed on the middle plate 920 using various methods such as inhaling air. Since the middle plate 920 and the bottom plate 240 include through holes 235 and 245, respectively, the pressure reducing unit 930 may apply a force to the lens disk downward. The pressure reducing unit 930 applies a force to the lens disk downward, so that the lens disk can bend more smoothly.

10 is a plan view of a top plate and a middle plate in a preform manufacturing apparatus according to a second embodiment of the present invention.

The middle plate 920, like the middle plate 230 according to the first embodiment, includes a through hole 925, and the through hole 925 has a width (width) equal to or greater than the width (width) of the lens disk. , Includes a first through hole 1010 having a height higher than that of the lens disk, and a first through hole 1010 and a second through hole 1015 having a width (width) narrower than the width (width) of the lens disk do. When the height of the first through hole 1010 is the same as the height of the lens disc, the top plate 910 disposed on the upper portion of the middle plate 920 may contact the lens disc, and the heat source included in the top plate 910 may This is because there is a concern that the lens disk may be damaged by the high temperature.

Similar to the middle plate 230 according to the first embodiment, each through hole 1010 and 1015 included in the middle plate 920 is disposed to have a concentric circle shape having the same center.

In addition, like the middle plate 230 according to the first embodiment, the middle plate 920 may further include a groove 1020 connecting the through holes 925 to each other.

11 is a view showing a state in which the lens disk according to the second embodiment of the present invention is disposed in a preform manufacturing apparatus.

The lens disk 510 is disposed in the through hole 920 of the middle plate 920. As described above, the height of the first through hole 1010 is formed higher than the height of the lens disk 510.

12 is a view showing a state in which the top plate according to the second embodiment of the present invention heats the lens disk.

The top plate 910 is disposed above the middle plate 920. Since the top plate 910 includes a heat source therein, when the top plate 910 is disposed on the upper portion of the middle plate 920, the lens disk 510 disposed on the middle plate 920 is heated.

13 is a view showing a state in which the lens disk is bent according to the second embodiment of the present invention.

When the lens disk 510 is heated, since it is disposed on the through hole 925 of the middle plate 920, it is naturally bent downward by gravity. Additionally, the preform manufacturing apparatus 110 according to the second embodiment applies suction force to the lower portion of the lens disc 510 using the depressurizing portion 930, so that the lens disc 510 can bend more smoothly to the lower portion. . As described above, the lens disk 510 can be fully bent without contacting the middle plate 920, and the center portion can be more smoothly projected.

14 is a flow chart showing a method of manufacturing a preform by a preform manufacturing apparatus according to a second embodiment of the present invention. Since the preform manufacturing method has been described in detail with reference to FIGS. 9 to 13, detailed description will be omitted.

The lens disk 510 is disposed on the middle plate 920 having one or more through holes (S1410).

The preform manufacturing apparatus 110 arranges the upper plate 910 at the upper end of the middle plate to fix the middle plate 920 (S1420).

The preform manufacturing apparatus 110 heats the lens disk 510 disposed on the middle plate 920 using the heat source in the top plate 910 disposed on the upper end of the middle plate 920 (b1430).

The preform manufacturing apparatus 110 additionally unfolds the lens disk 510 to the lower end using the decompression unit 930 (S1440).

15 is a view showing a preform of a lens manufactured by a preform manufacturing apparatus according to a first or second embodiment of the present invention.

The preform 1510 of the lens by the preform manufacturing apparatus 110 according to the first or second embodiment may have an effective height (Sag) of the preforms of all lenses manufactured by the suction force of the dark and dark portions as well as gravity. In particular, since the preform manufacturing apparatus 110 according to the first embodiment heats the lens disk 510 using a light source, all the lens disks 510 can be uniformly heated, leading to more reliable results. You can.

In addition, since the preform 1510 of the lens is primarily heated in the manufacturing process by the preform manufacturing apparatus 110 according to the first or second embodiment, it is possible to uniformly and appropriately distribute heat even later in the manufacturing process of the lens. Can have In a conventional lens manufacturing apparatus, a manufacturing process is performed in a vacuum state or a nitrogen atmosphere due to the material characteristics of the lens disk 510, and the heat transfer efficiency is relatively low in a vacuum state or a nitrogen atmosphere, so that the preform of the lens disk or lens is completely heated or uniform. Frequently, it could not be heated. Since the preform 510 of the lens to be introduced into the lens manufacturing apparatus 120 is already primarily heated in the preform manufacturing process and has a uniform heat distribution, it can have a uniform and appropriate heat distribution in the lens manufacturing process later. . Accordingly, the manufactured lens may have excellent performance such as roughness and uniformity of curvature.

16 is a view showing the configuration of a lens manufacturing apparatus according to an embodiment of the present invention.

Referring to FIG. 16, the lens manufacturing apparatus 120 according to an embodiment of the present invention includes an upper core 1610, a lower core 1620, a heat source 1630, and a gas entrance 1640.

The upper core 1610 and the lower core 1620 press the preform 1510 of the lens to mold it, thereby manufacturing a lens. The upper core 1610 and the lower core 1620 have a shape of a lens to be manufactured complementarily, and press the preform 1510 of the lens to mold it, thereby manufacturing a lens.

The heat source 1630 heats the preform 1510 of the lens. In order for the upper core 1610 and the lower core 1620 to mold the preform 1510 of the lens, the preform 1510 of the lens must be heated to an appropriate temperature. The heat source unit 1630 heats the preform 1510 of the lens, so that the temperature of the preform 1510 of the lens reaches a temperature suitable for mold molding.

The gas entrance 1640 discharges the gas to the outside of the lens manufacturing apparatus 120 to make the inside of the lens manufacturing apparatus 120 vacuum, or the cooling gas is introduced into the lens manufacturing apparatus 120 to produce the lens manufacturing apparatus 120 ) Cool the inside. In particular, as the gas entrance 1640 makes the inside of the lens manufacturing apparatus 120 in a vacuum state, traces of gas that may occur in the lens material during the lens manufacturing process can be removed on the surface of the lens.

17 is a view showing a state in which a lens manufacturing apparatus according to an embodiment of the present invention creates a vacuum state in which a preform of a lens is disposed.

The preform 1510 of the lens to be molded by being pressed on the lower core 1620 is disposed. Subsequently, the lens manufacturing apparatus 120 uses the gas inlet 1640 to make the inside vacuum in order to create an appropriate environment for the manufacture of the lens. Due to the nature of the material of the preform 1510 of the lens and the nature in which gas may be generated in the lens manufacturing process, an environment in which a vacuum or oxygen is rarely included is preferable. Preferably, the lens manufacturing apparatus 120 has a gas entrance 1640. Use to make the inside into a vacuum, or by introducing nitrogen to form the inside into a nitrogen atmosphere.

18 is a view showing a state in which the lens manufacturing apparatus according to an embodiment of the present invention heats the preform of the lens.

When a vacuum state or a nitrogen atmosphere is formed, the preform 1510 of the lens is heated using a heat source 1630 for mold molding. Since the preform was primarily heated in the manufacturing process, the preform 1510 of the lens can easily reach a temperature suitable for mold molding even if a vacuum state or a nitrogen atmosphere is formed, and the preform 1510 of the lens has a uniform temperature distribution Can have

19 is a view showing a state in which the lens manufacturing apparatus according to an embodiment of the present invention presses the preform of the lens.

When the preform 1510 of the lens is sufficiently heated, the upper core 1610 and the lower core 1620 press the preform 1510 of the lens to mold it.

20 is a view showing a state in which the lens manufacturing apparatus according to an embodiment of the present invention is cooled.

After mold molding with the upper core 1610 and the lower core 1620, the lens manufacturing apparatus 120 lowers the increased internal temperature. As the cooling gas flows into the interior of the lens manufacturing apparatus 120 through the gas entrance 1640, the internal temperature of the lens manufacturing apparatus 120 is lowered. Thereafter, the manufactured lens is taken out, thereby completing the manufacturing process of the lens.

21 is a view showing a lens manufactured by a lens manufacturing apparatus according to an embodiment of the present invention.

The lens 2110 manufactured through the above-described preform process and the lens manufacturing process may have an effective height (Sag) and have excellent surface roughness because the primary heat treatment is performed in the preform process. In addition, as the preform process is performed, a lens having a uniform curvature can be produced in all parts, especially in the center part.

The infrared lens 2200, the first lens 2210, and the second lens 2220 disclosed below may be lenses manufactured by each process of the above-described preform manufacturing apparatus and lens manufacturing apparatus.

22 is a view showing the configuration of an infrared lens according to an embodiment of the present invention, FIGS. 23 and 24 are graphs showing distortion aberration and MTF characteristics of the infrared lens according to the first embodiment of the present invention, 25 is a view showing a configuration and a Sag value of the first lens according to the first embodiment of the present invention.

22 to 25, the infrared lens 2200 according to an embodiment of the present invention includes a first lens 2210, a second lens 2220 and a sensor unit 2230.

The infrared lens 2200 includes a first lens 2210, a second lens 2220, and a sensor unit 2230 sequentially from an object side (-y-axis direction of the first lens), and the sensor unit 2230 The phase 2240 is formed on the + y axis direction.

The first lens 2210 includes a first surface 2214 and a second surface 2218.

The first surface 2214 is composed of an aspheric surface, and has a radius of curvature (Radius) of 11.16 mm and a thickness of 5.50 mm. In addition, the first surface 2214 has a refractive index (Refractive Index) of 2.61 and a dispersion ratio (Abe number, Abbe Number) of 108.52. Here, the thickness of the first surface 2214 means a distance between the first surface 2214 and the second surface 2218.

In addition, the dispersion ratio is calculated by the following equation (1).

Here, Nr is a material refractive index at a wavelength of 10 μm, Nl is a material refractive index at a wavelength of 12 μm, and N1 is a material refractive index at a wavelength of 8 μm.

The second surface 2218 has an aspherical surface like the first surface 2214, and has a curvature radius of 8.79 mm and a thickness of 5.93 mm. The second surface 2218 is implemented with a relatively small radius of curvature compared to the first surface 2214. Here, the thickness of the second surface 2218 means a distance between the second surface 2218 and the second lens 2220.

As shown in FIG. 25, the second surface 2218 includes a diffractive optical element (2510, Diffractive Optical Element). The diffractive optical element 2510 is implemented on the second surface 2218 of the first lens 2210 to minimize aberrations that may occur in the infrared lens 2200. The diffractive optical element 2510 may be implemented with three rings (Number of Rings), and may have 6.226 μm as a depth of depth. The first lens 2210 has a diffractive optical element 2510 on the second surface 2218, and thus has a focal length of 419.31mm.

The second lens 2220 includes a third surface 2224 and a fourth surface 2228.

The third surface 2224 is composed of an aspheric surface and has a curvature radius of 23.95 mm and a thickness of 4.50 mm. In addition, the third surface 2224 has a refractive index of 2.61 and a dispersion ratio of 108.52. The second lens 2220 may be implemented to have the same refractive index and dispersion ratio as the first lens 2210. Here, the thickness of the third surface 2224 means a distance between the third surface 2224 and the fourth surface 2228.

The fourth surface 2228 is composed of an aspherical surface similar to the third surface 2224, and has a curvature radius of -88.26 mm and a thickness of 6.06 mm. Here, the thickness of the fourth surface 2228 refers to a distance between the fourth surface 2228 and the sensor 2230.

The radius of curvature of each surface is obtained by Equation 2 below according to each aspherical coefficient in Table 1 below.

if K A B C D E Front page -0.439531 0.274800 E-04 0.786217
E-06 -0.203333 E-07 0.836154
E-10 0.000000 P. 2 0.203870 0.328725
E-04 0.254764
E-05 -0.288032 E-06 0.191166
E-08 0.000000 P. 3 1.946014 -0.568063
E-04 0.414937
E-05 -0.332197 E-06 0.808806
E-08 -0.110960
E-09 4th side -221.704664 -0.882338
E-04 0.529436
E-05 -0.299315 E-06 0.972805
E-08 -0.163132
E-10

Here, k is the cone surface coefficient, c is the central curvature, h is the distance from the optical axis to the concave or convex surface, and K, A, B, C, D, and E are aspheric coefficients in Table 1.

In order for the spherical lens to exhibit the effect of the aspheric lens, a larger number of lenses have to be used, so the infrared lens implemented with the spherical lens has a problem in that its size increases. In order to solve this problem, the infrared lens 2200 has aspherical lenses 2210 and 2220, and thus has the same or more effect than the conventional infrared lens even at a small size compared to the infrared lens implemented as the conventional spherical lens. You can.

The sensor 2230 includes a fifth surface 2234 and a sixth surface 2238.

The fifth surface 2234 has an infinite radius of curvature, and has a thickness of 0.7 mm. In addition, the fifth surface 2234 has a refractive index of 3.42 and a dispersion ratio of 2017.92. The thickness of the fifth surface 2234 means the distance between the fifth surface 2234 and the sixth surface 2238.

The sixth surface 2238 has an infinite radius of curvature, and has a thickness of 1.04 mm. Here, the thickness means a distance between the sixth surface 2238 and the image 2240, that is, the image 2240 is formed at 1.04 mm behind the sensor 2230 (+ y-axis direction of the sensor).

The infrared lens 2200 has a distortion factor of 0.00% at 0.0F (the center region of the sensor), a distortion factor of -1.48% at 0.7F, and a distortion factor of -3.07% at 1.0F (the outer region of the sensor).

The infrared lens 2200 has 15.0 mm as a focal length and f / 1.03 as an aperture-based f-number as each of the above-described components is provided. The infrared lens 2200 has 8.16 mm as a maximum image circle and 8 to 12 μm as a waveband. In addition, the infrared lens 2200 has a field of view (FOV) of 24.5 degrees horizontal, 18.5 degrees vertical, and 30.4 degrees diagonal.

The infrared lens 2200 has the above-described respective configurations, and thus has the following Modulation Transfer Function (MTF). Infrared lens 2200 has an MTF of 56.6% at 0.0F, an MTF of 48.1% with a Tangential component at 0.7F, a 51.2% MTF with a Sagittal component at 1.0F, and a 39.8% MTF of 49.8% with a Tangential component at 1.0F. Have That is, the infrared lens 2200 has excellent performance by having an MTF significantly exceeding 30% even at 1.0F.

22 is a view showing the configuration of an infrared lens according to an embodiment of the present invention, FIGS. 26 and 27 are graphs showing distortion aberration and MTF characteristics of the infrared lens according to the second embodiment of the present invention, 28 is a view showing a configuration and a Sag value of the first lens according to the second embodiment of the present invention.

The first lens 2210 includes a first surface 2214 and a second surface 2218.

The first surface 2214 is composed of an aspheric surface and has 14.01 mm as a radius and 6.00 mm as a thickness. In addition, the first surface 2214 has a refractive index (Refractive Index) of 2.61 and a dispersion ratio (Abe number, Abbe Number) of 108.52. Here, the thickness of the first surface 2214 means a distance between the first surface 2214 and the second surface 2218.

The second surface 2218 is composed of an aspherical surface like the first surface 2214, and has a curvature radius of 12.11 mm and a thickness of 6.30 mm.

As shown in FIG. 28, the second surface 2218 includes a diffractive optical element (2810, Diffractive Optical Element). The diffractive optical element 2810 is implemented on the second surface 2218 of the first lens 2210 to minimize aberrations that may occur in the infrared lens 2200. The diffractive optical element 2810 may be implemented with four rings (Number of Rings), and may have 6.226 μm as a depth of depth. As the first lens 2210 includes the diffractive optical element 2510 on the second surface 2218, it has a focal length of 470.85mm.

The second lens 2220 includes a third surface 2224 and a fourth surface 2228.

The third surface 2224 is composed of an aspheric surface and has a curvature radius of 60.14 mm and a thickness of 4.80 mm. In addition, the third surface 2224 has a refractive index of 2.61 and a dispersion ratio of 108.52. The second lens 2220 may be implemented to have the same refractive index and dispersion ratio as the first lens 2210.

The fourth surface 2228 is composed of an aspherical surface like the third surface 2224, and has a curvature radius of -48.56 mm and a thickness of 9.08 mm.

The radius of curvature of each surface is obtained by Equation 2 described above according to each aspherical coefficient in Table 2 below.

if K A B C D E Front page -0.549800 0.145660 E-04 0.384960
E-07 -0.281521 E-08 -0.177904
E-10 0.000000 P. 2 -0.153466 0.760369
E-05 0.499915
E-06 -0.699259 E-07 0.416112
E-09 0.000000 P. 3 -14.449233 -0.325849
E-04 -0.212482
E-06 -0.419932 E-07 0.414432
E-09 -0.477982
E-11 4th side 28.033542 0.219654
E-04 -0.874826
E-06 -0.370851 E-08 0.549507
E-10 0.641932
E-12

The sensor 2230 includes a fifth surface 2234 and a sixth surface 2238.

The fifth surface 2234 has an infinite radius of curvature, and has a thickness of 0.73 mm. In addition, the fifth surface 2234 has a refractive index of 4.01 and a dispersion ratio of 942.38.

The sixth surface 2238 has an infinite radius of curvature, and has a thickness of 1.10 mm.

The infrared lens 2200 has a distortion factor of 0.00% at 0.0F (the central region of the sensor), a distortion factor of -0.27% at 0.7F, and a distortion factor of -0.68% at 1.0F (the outer region of the sensor).

The infrared lens 2200 has 19.0 mm as the focal length and f / 1.03 as the f-value (Aperture-based f-number) as each of the above-described components is provided. The infrared lens 2200 has 8.16 mm as a maximum image circle and 8 to 12 μm as a waveband. In addition, the infrared lens 2200 has a field of view (FOV) of 19.8 degrees horizontally, 14.9 degrees vertical and 24.6 degrees diagonal.

The infrared lens 2200 has the above-described respective configurations, and thus has the following Modulation Transfer Function (MTF). The infrared lens 2200 has an MTF of 40.4% at 0.0F, a 52.1% MTF with a Tangential component at 0.7F, a 56.1% MTF with a Sagittal component at 1.0F, a 39.6% MTF with a Tangential component at 3F, and a 38.5% MTF at Sagittal component. Have

The first lens 2210 and the second lens 2220 included in the infrared lens 2200 according to the first embodiment or the first lens 2210 and the second lens included in the infrared lens 2200 according to the second embodiment The 2 lens 2220 may be implemented as a low dispersion lens. Since each lens 2210, 2220 is implemented as a low-dispersion lens, it can bring advantageous effects to correct chromatic aberration compared to a conventional infrared lens.

Each lens 2210, 2220 may be implemented with a chalcogenide-based composition, and each component ratio of the composition is as follows.

Ge 22.5 to 27.5% by weight, Sb 12.5 to 17.5% by weight, Se is composed of 60% by weight.

When each lens (2210, 2220) is implemented with such a composition, each lens (2210, 2220) has a transmittance of 60% or more for light of 8 to 12 micrometer wavelength, and a glass transition temperature of 270 to 300 ° C. It has a Vickers hardness of 170 kgf / mm2 or more. In addition, when molded using a mold, each lens 2210 and 2220 may implement optical performance.

On the other hand, each lens (2210, 2220) may be implemented as a chalcogenide-based composition as follows.

The composition of each lens 2210, 2220 includes germanium (Ge), gallium (Ga), antimony (Sb), and selenium (Se), but 5 ≦ germanium ≦ 25, 2 ≦ gallium ≦ 20, 5 based on mol% It may have a content of ≤ antimony ≤ 25, 55 ≤ selenium ≤ 70. The value of the sum of the content of gallium and the content of germanium may be constant so that gallium can be added by replacing the content of germanium.

The composition of each lens 2210, 2220 preferably has a content of 10 ≤ germanium ≤ 22.5, 5 ≤ gallium ≤ 15, 7.5 ≤ antimony ≤ 12.5, 60 ≤ selenium ≤ 67.5 on a molar% basis, and gallium is germanium. Can replace the content of Regarding such a numerical value range, it will be described later together with specific examples.

Further, the composition of each lens 2210, 2220 may further include at least one additive selected from the group consisting of halogen elements, halides, alkali metals, alkaline earth metals, and selenium compounds. The additive may have a content of 0 <additive≤10 based on mol%.

The halogen element can be added in the form of a single halogen element. For example, the halogen element can be Cl, Br, or I. In addition, halide means a compound form of a halogen element and an alkali metal. For example, the halide can be RY, where R is Li, Na, K, Rb, or Cs, and Y is Cl, Br or I. Further, in the case of an alkali metal or alkaline earth metal component, when added to glass, it may be added in the form of a metallic element (single element) or a selenium compound of each component. For example, the alkali metal may be Li, Na, K, Rb or Cs, or a selenium (Se) compound of each single element (Li, Na, K, Rb or Cs). Further, the alkaline earth metal may be Ca, Sr or Ba, or a selenium compound of each single element (Ca, Sr or Ba).

When an additive is included in the composition of each lens 2210 and 2220, the sum of the content of gallium, the content of the additive and the content of germanium may be constant so that gallium and the additive can be added by replacing the content of germanium. You can.

That is, the composition of each lens 2210, 2220 may have a composition of Ge-Ga-Sb-Se or Ge-Ga-Sb-Se-X. Here, X refers to an additive. As the content of germanium is lowered, a rapid decrease in thermal stability may be involved. The composition of each lens 2210, 2220 can prevent a rapid decrease in thermal stability by adjusting the content of gallium and X components.

In addition, at least one or more of the refractive index and dispersion characteristics of the composition of each lens 2210 and 2220 may be adjusted according to a change in the content of antimony or a change in the content of antimony and additives. For example, the refractive index value of the composition of each lens 2210, 2220 can be adjusted according to the antimony content. In addition, the dispersion properties and thermal properties of the composition of each lens 2210, 2220 can be adjusted according to the content of the additive to be added.

That is, the composition of each lens 2210, 2220 can secure high thermal stability and refractive index by changing the relative composition ratios of germanium, gallium, antimony, and selenium according to the above-described content range and alternative conditions. In addition, the composition of each lens (2210, 2220) by selectively adding the X component, it is possible to adjust the mechanical / optical properties.

Hereinafter, test results for confirming the properties of the composition of each lens 2210, 2220 such as transmittance, Vickers hardness, thermal expansion coefficient, glass transition temperature, and softening point will be described.

All specimens used in the test were typically produced following a melt / quench process to produce chalcogenide glass. The glass specimens of each composition were in the form of circular rods and were commonly fixed to a diameter of 10 mm, and the length was made to exceed at least 10 cm. The specific manufacturing process is exemplarily as follows.

As a pretreatment process of the silica ampoule, the silica ampoule is washed with acetone and then heat-treated at 600 ° C. Then, the starting material is weighed according to the composition ratio of each specimen in a glove box filled with Ar gas, and then charged into a silica ampoule. The silica ampoule is melted and sealed after making the vacuum inside. Using an electric furnace, the temperature was raised to 22000 ° C over 6 hours, and then maintained at 22000 ° C for 12 hours or more and then cooled. In the case of cooling conditions, two methods were used, most commonly used water quenching and slow cooling in air. Subsequently, the composition was maintained at a temperature set based on the glass transition temperature of each composition for 3 hours and then slowly cooled to room temperature over 6 hours to perform an annealing process.

29A to 29D show a comparison of a transmission spectrum of 2 mm thickness of germanium-antimony-selenium ternary glass and germanium-gallium-antimony-selenium tetracomponent glass (chalcogenide glass composition according to an embodiment of the present application). It is a graph.

29A to 29D, antimony and selenium contents were fixed based on the four-component starting composition, and gallium was added to replace germanium. Referring to FIGS. 29A to 29D, the infrared transmission end does not significantly move in the quadruplex-based glass (when x = 5, 10, or 15) of the present application in comparison with the ternary glass (when x = 0), 8 Good infrared transmittance of more than 50% is seen in the ~ 12 μm band. In the case of such a glass composition, since the refractive index is relatively larger than that of oxide glass, it exhibits relatively low transmittance due to Fresnel reflection. However, as the lens is manufactured by coating the antireflection film, the transmittance in the 8-12 μm band may be increased to 90% or more. In addition, absorption occurring at a position of 12.5 μm wavelength in the transmission spectrum is caused by oxygen, and is the largest in germanium-antimony-selenium ternary glass without gallium (see FIGS. 29A, 29C, and 29D). This can be interpreted as a phenomenon in which the starting material of germanium tends to be more easily oxidized than that of gallium. That is, as the content of germanium is replaced by adding gallium, an effect of reducing the loss of permeability in the vicinity of 12 μm may occur simultaneously.

30 is a graph comparing Vickers hardness of a germanium-antimony-selenium ternary glass and a germanium-gallium-antimony-selenium four-component glass (chalcozinide glass composition according to an embodiment of the present application).

Referring to FIG. 30, it can be seen that the content of germanium is replaced and the hardness value of the glass is maintained at a similar level even when gallium is added. Specifically, when gallium was added as a substitute for germanium in a content of 5, 10, and 15 based on mol%, the hardness value of the glass is maintained at a level similar to that of the ternary glass.

FIG. 31 is a graph comparing thermal expansion coefficients of a germanium-antimony-selenium ternary glass and a germanium-gallium-antimony-selenium four-component glass (chalcozinide glass composition according to an embodiment of the present application).

Referring to FIG. 31, the thermal expansion coefficient value of the glass tends to be maintained or improved at a similar level even when gallium is added while replacing the content of germanium. Specifically, when gallium was added by replacing germanium in a content of 5, 10, and 15 based on mol%, the thermal expansion coefficient of the glass was maintained at a level similar to that of the ternary glass, or improved in some cases.

32 and 33 are graphs comparing glass transition temperatures and softening points of germanium-antimony-selenium ternary glass and germanium-gallium-antimony-selenium tetracomponent glass (chalcozinide glass composition according to an embodiment of the present application) to be.

32 and 33, as gallium is added to replace the content of germanium, the glass transition temperature and softening point of the glass tends to decrease somewhat. However, the glass transition temperature and softening point of the glass made of the composition of each lens 2210, 2220 are still physical properties suitable for the mold molding process, and may include other additives as necessary.

Other additives may further include at least one additive selected from the group consisting of halogen elements, halides, alkali metals, alkaline earth metals, and selenium compounds. The additive may have a content of 0 <additive≤10 based on mol%.

Also illustratively, the halogen element can be Cl, Br, or I. Further, the halide can be RY (where R is Li, Na, K, Rb, or Cs, and Y is Cl, Br or I). Further, the alkali metal may be Li, Na, K, Rb or Cs. Further, the alkaline earth metal may be Ca, Sr or Ba. In the case of an alkali metal or alkaline earth metal component, when added to glass, it may be added in the form of a metallic element or in the form of a selenium compound of each component.

Referring to the test results discussed above, the composition of each lens 2210, 2220 is 5≤ germanium≤25, 2≤gallium≤20, 5≤antimony≤25, 55≤ selenium≤70 in terms of mole%, Preferably, while having the content of 10≤ germanium ≤ 22.5, 5 ≤ gallium ≤ 15, 7.5 ≤ antimony ≤ 12.5, 60 ≤ selenium ≤ 67.5, gallium may be set to replace the content of germanium.

Since the composition of each lens 2210, 2220 can be processed into a lens through a mold molding process, it may have a significantly lower process price than when using a conventional crystalline material. In addition, as the content of germanium having a relatively high raw material cost is low, the composition of each lens 2210, 2220 has an advantage that the raw material price is also cheaper than the existing glass material.

In addition, the composition of each lens (2210, 2220) can have a high refractive index and a variety of adjustable dispersion by selecting each component from the glass made of the above-described composition and content and changing the composition ratio. Furthermore, the lens to be manufactured can be made more compact.

In FIGS. 8 and 14, it is described that each process is executed sequentially, but this is merely illustrative of the technical idea of an embodiment of the present invention. In other words, a person skilled in the art to which one embodiment of the present invention pertains may execute or change one or more of the processes described in FIGS. 8 and 14 without departing from the essential characteristics of one embodiment of the present invention. 8 and 14 are not limited to the time-series order since the process may be applied in various modifications and variations by executing in parallel.

Meanwhile, the processes illustrated in FIGS. 8 and 14 may be implemented as computer readable codes on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data readable by a computer system is stored. That is, the computer readable recording medium includes magnetic storage media (eg, ROM, floppy disk, hard disk, etc.), optical reading media (eg, CD-ROM, DVD, etc.) and carrier waves (eg, the Internet). Storage). The computer-readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

The above description is merely illustrative of the technical spirit of the present embodiment, and those skilled in the art to which this embodiment belongs may be able to make various modifications and variations without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical spirit of the present embodiment, but to explain, and the scope of the technical spirit of the present embodiment is not limited by these embodiments. The protection scope of the present embodiment should be interpreted by the claims below, and all technical spirits within the equivalent range should be interpreted as being included in the scope of the present embodiment.

100: lens manufacturing system
110: preform manufacturing apparatus
120: lens manufacturing apparatus
210: light source
220, 910: top
230, 920: Medium
234: first mid-range
238: Second Mid Edition
235, 245, 320: through hole
240: bottom
250, 930: pressure reducing section
310, 1010: first through hole
315, 1015: second through hole
410, 1020: home
510: lens disc
1510: lens preform
1610: upper core
1620: lower core
1630: heat source
1640: Aircraft entrance
2110: lens
2220: infrared lens
2210: first lens
2214: front page
2218: Scene 2
2220: second lens
2224: p. 3
2228: p. 4
2230: sensor unit
2234: p. 5
2238: p. 6
2240: Award
2510, 2810: Diffractive optical element

Claims (14)

In the device for producing a preform (Preform) of a lens manufactured by mold molding,
A light source irradiating light for heating the lens disc;
A middle plate having a plurality of through holes in which the lens disk is to be arranged and grooves connecting the through holes to each other;
An upper plate disposed at an upper end of the middle plate to fix the middle plate;
A pressure-reducing unit that applies suction force downward to the lens disk disposed on the middle plate; And
It is disposed at the lower end of the middle plate to fix the middle plate together with the top plate, and includes a lower plate having a through hole so that the force applied by the depressurization portion can be transmitted to the lens disk,
The through hole of the middle plate includes a first through hole having a width and height greater than or equal to the width and height of the lens disk, and a second through hole having a width smaller than the width of the lens disk and the first through hole,
The width of the second through hole is formed wider than the effective diameter of the portion protruding from the preform of the lens,
The through-hole of the lower plate has a diameter smaller than the first through-hole and the second through-hole, characterized in that the preform production apparatus of the lens. According to claim 1,
The light source,
Preform production device of the lens, characterized in that for irradiating light in the ultraviolet wavelength band. According to claim 1,
The top plate,
Preform production device of the lens, characterized in that it is implemented with a light-transmitting material so that the light irradiated by the light source can be transmitted to the lens disk disposed on the middle plate. delete According to claim 1,
The middle plate,
And a first middle plate having the first through hole and a second middle plate having the second through hole. delete In the method for producing a lens preform (Preform) production device of a lens manufactured by mold molding,
A first arrangement process in which a lens disk is disposed on a middle plate having a plurality of through-holes and grooves connecting the through-holes to each other;
A second arrangement process in which an upper plate is disposed at an upper end of the middle plate and a lower plate is disposed at a lower portion of the middle plate to fix the middle plate;
A light irradiation process for irradiating light for heating the lens disk; And
And a depressurization process of applying suction force to the lower portion of the lens disk disposed on the middle plate,
The through hole provided in the middle plate includes a first through hole having a width and height equal to or greater than the width and height of the lens disk, and a second through hole having a width smaller than the width of the lens disk and the first through hole and,
The width of the second through hole is formed wider than the effective diameter of the portion protruding from the preform of the lens,
The lower plate has a through-hole having a diameter smaller than that of the first through-hole and the second through-hole, so that the force exerted in the decompression process can be transmitted to the lens disc, thereby producing a preform of the lens. Way. The method of claim 7,
The light irradiation process,
Method for producing a preform of a lens, characterized by irradiating light in the ultraviolet wavelength band. The method of claim 7,
The top plate,
A method for producing a preform of a lens, characterized in that it is implemented with a light-transmitting material so that light irradiated in the light irradiation process can be transmitted to a lens disk disposed on the middle plate. delete The method of claim 7,
The middle plate,
And a first middle plate having the first through hole and a second middle plate having the second through hole.
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