Plastic lens and molding apparatus for manufacturing plastic lens

Abstract

A plastic lens and a molding apparatus for manufacturing the plastic lens are provided. The plastic lens includes an optical portion that refracts light and a flange portion that extends from the optical portion, where a molded line is continuously formed on a side surface of the flange portion along a circumference of the flange portion. The molding apparatus includes: a first mold including a first core portion and a first body portion accommodating the first core portion; a second mold including a second core portion and a second body portion accommodating the second core portion; and a third mold including a third body portion coupled to a first surface of the second body portion facing the first body portion.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority from Korean Patent Application No. 10-2023-0075104 filed on June 12, 2023, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety for all purposes by reference. Technical Field

[0003] The following description relates to a plastic lens and a molding apparatus for producing the plastic lens. Background Art

[0004] Typically, a lens implemented in a camera module of a portable electronic device (such as but not limited to a smart phone) is a plastic lens, and such a plastic lens is manufactured through an injection molding process.

[0005] That is, the injection mold has a cavity corresponding to the shape of the lens, and the plastic lens is manufactured by injecting molten resin into the cavity.

[0006] However, in the example of the injection molding method, there may be a problem in that residual stress may occur in a gate portion for supplying molten resin to a cavity, thereby deteriorating the optical performance of the lens.

[0007] In addition, the flow rate of the molten resin in the parts of the cavity is different, and therefore, flow marks or weld lines may appear on the lens, which may reduce the optical performance of the lens.

[0008] The above information is presented as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above may be applicable as prior art with respect to the present disclosure. Summary of the invention

[0009] This Summary is provided to introduce a selection of concepts in a simplified form that are further described in the Detailed Description below. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0010] In a general aspect, a plastic lens includes an optical portion refracting light and a flange portion extending from the optical portion, wherein a profile line is continuously formed along a circumference of the flange portion on a side surface of the flange portion.

[0011] T_max / T_min≥3.0, where T_max is the maximum thickness of the optical portion, and T_min is the minimum thickness of the optical portion.

[0012] The diameter of the plastic lens may be 10 mm or more.

[0013] One or more cut portions may be disposed on an edge of the flange portion, and the one or more cut portions may have a greater birefringence than other portions of the edge of the flange portion.

[0014] A plurality of cutting portions may be provided, and the plurality of cutting portions may be spaced apart from each other along a circumference of the flange portion.

[0015] In general, a molding apparatus for manufacturing a plastic lens comprises: a first mold comprising a first core portion and a first main body portion accommodating the first core portion; a second mold comprising a second core portion and a second main body portion accommodating the second core portion; and a third mold comprising a third main body portion connected to a first surface of the second main body portion facing the first main body portion, wherein the first mold is configured to be movable relative to the second mold and the third mold, wherein the first mold is configured to move to a position closer to a first surface of the second main body portion than to a first surface of the third main body portion facing the first main body portion, and wherein, when the first mold moves, a cavity surrounded by the first core portion, the second core portion, the second main body portion, and the third main body portion is formed.

[0016] The third body portion may include one or more recessed portions, and the first surface of the third body portion is a bottom surface of the one or more recessed portions.

[0017] The one or more concave portions may be provided in plural, and the plurality of concave portions may be spaced apart from each other in the circumferential direction.

[0018] The first surface of the second core portion may be located lower than the first surface of the second body portion, and the first surface of the first core portion facing the first surface of the second core portion may be configured to move between the first surface of the second body portion and the first surface of the third body portion.

[0019] When forming the cavity, a distance between an outer end of the first surface of the first core portion and an outer end of the first surface of the second core portion may be smaller than a distance between an outer end of the first surface of the second core portion and a first surface of the third body portion.

[0020] 0.1≤T1 / T2<1 is satisfied, where T1 is the distance between the outer end of the first surface of the first core portion and the outer end of the first surface of the second core portion, and T2 is the distance between the outer end of the first surface of the second core portion and the first surface of the third body portion.

[0021] The one or more concave portions may be formed to have a larger volume at an upper end of the one or more concave portions than at a lower end of the one or more concave portions.

[0022] The first body portion and the second body portion may be each provided with a first heating unit and a flow path, the first heating unit being configured to generate heat, and a fluid flowing through the flow path.

[0023] A second heating unit configured to generate heat may be coupled to each of the first core portion and the second core portion.

[0024] In general, a molding apparatus for manufacturing a plastic lens comprises: a first movable mold comprising a first core portion and a first main body portion accommodating the first core portion; a second mold comprising a second core portion and a second main body portion accommodating the second core portion; and a third mold comprising one or more recessed portions and a third main body portion, the third main body portion being connected to a first surface of the second main body portion facing the first main body portion, wherein, when the first mold moves toward the second mold, a portion of the raw material exceeding the weight of the plastic lens is discharged from the mold cavity into the one or more recessed portions.

[0025] Other features and aspects will be apparent from the following detailed description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A method of manufacturing a plastic lens according to one or more embodiments is shown.

[0027] Figure 2 The raw plastic material is shown positioned in the second mold.

[0028] Figure 3 The first mold is shown moving.

[0029] Figure 4 A state in which a plastic raw material is heated and pressed by a mold is shown.

[0030] Figure 5 yes Figure 4 Magnified view of part A.

[0031] Figure 6 A state in which a molded lens is separated from a mold is shown.

[0032] Figure 7 A state in which a plastic raw material discharged to the outside of a cavity during a lens molding process is removed from a mold is shown.

[0033] Fig. 8A , Figure 8B , Figure 8C and Fig.8D : are plan views showing various examples of the second mold and the third mold.

[0034] Fig.9A, Fig. 9B and Fig. 9C are cross-sectional views of various examples of the concave portion.

[0035] Fig.10 is a plan view of a plastic lens according to one or more embodiments.

[0036] Fig.11 A perspective view of a plastic lens according to one or more embodiments is shown.

[0037] Throughout the drawings and detailed description, unless otherwise described, the same reference numerals refer to the same elements. For clarity, illustration, and convenience, the drawings may not be drawn to scale, and the relative sizes, proportions, and descriptions of the elements in the drawings may be exaggerated. DETAILED DESCRIPTION

[0038] Hereinafter, although examples of the present disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the examples are not limited thereto.

[0039] The following specific embodiments are provided to help the reader gain a comprehensive understanding of the methods, devices, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, devices, and / or systems described herein will be apparent after understanding the present disclosure. For example, the order of operations described herein is merely an example and is not limited to the order set forth herein, but may be changed as will be apparent after understanding the present disclosure, except for operations that must occur in a certain order. In addition, descriptions of features known in the art may be omitted for clarity and brevity.

[0040] The features described herein may be implemented in different forms and are not to be construed as being limited to the examples described herein. Rather, the examples described herein are provided only to illustrate some of the many possible ways to implement the methods, devices, and / or systems described herein that will be apparent after understanding the present disclosure.

[0041] Throughout the specification, when an element (such as a layer, a region, or a substrate) is described as being “on”, “connected to”, or “coupled to” another element, it may be directly “on”, directly “connected to”, or directly “coupled to” the other element, or one or more other elements may be present between them. Conversely, when an element is described as being “directly” “on”, “directly connected to”, or “directly coupled to” another element, there are no other elements present between them.

[0042] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more of the associated listed items; similarly, "at least one of..." includes any one of the associated listed items and any combination of any two or more of the associated listed items.

[0043] Although terms such as "first", "second", and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions are not limited by these terms. Instead, these terms are only used to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Therefore, the first member, first component, first region, first layer, or first portion mentioned in the examples described herein may also be referred to as the second member, second component, second region, second layer, or second portion without departing from the teachings of the examples.

[0044] For ease of description, spatially relative terms such as "above", "upper", "below", "lower", etc. may be used herein to describe the relationship of one element to another element as shown in the drawings. In addition to the orientation depicted in the drawings, such spatially relative terms are intended to also include different orientations of the device in use or operation. For example, if the device in the drawings is turned over, an element described as being "above" or "upper" relative to another element will then be "below" or "lower" relative to the other element. Therefore, the term "above" includes both the orientation of the above and below, depending on the spatial orientation of the device. The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative terms used herein will be interpreted accordingly.

[0045] The terms used herein are only used to describe various examples and are not used to limit the present disclosure. The words "a", "an" and "the" are intended to include plural forms as well, unless the context clearly indicates otherwise. The terms "include", "comprises" and "have" specify the presence of stated features, quantities, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements and / or combinations thereof.

[0046] Due to manufacturing techniques and / or tolerances, the shapes shown in the drawings may vary. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings but include shape variations that occur during manufacturing.

[0047] Herein, it is noted that the use of the term “may” with respect to an example, such as with respect to what an example may include or implement, means that there is at least one example that includes or implements this feature, and all examples are not limited thereto.

[0048] As will be apparent after understanding the present disclosure, the features of the examples described herein may be combined in various ways. In addition, although the examples described herein have multiple configurations, other configurations are also possible, as will be apparent after understanding the present disclosure.

[0049] One or more examples may provide a plastic lens having improved optical properties and a molding apparatus for manufacturing the plastic lens.

[0050] Figure 1 A method of manufacturing a plastic lens according to one or more embodiments is shown. In the following examples, the operations may be performed sequentially, but are not limited thereto. In the examples, the order of the operations may be changed, and at least two operations may be performed in parallel.

[0051] Reference Figure 1 , the method of manufacturing a plastic lens according to one or more embodiments includes a first operation (operation S1).

[0052] The first operation (operation S1) may be an operation of placing a plastic raw material in a mold for manufacturing a plastic lens (hereinafter referred to as a "mold"). The weight of the plastic raw material may be greater than the weight of the lens to be manufactured.

[0053] The method of manufacturing a plastic lens according to one or more embodiments includes a second operation (operation S2). The second operation (operation S2) may be an operation of heating the plastic raw material placed in the mold.

[0054] In the second operation (operation S2), the plastic raw material may be heated to a temperature higher than the glass transition temperature of the plastic raw material. Since the plastic raw material is heated to a temperature higher than the glass transition temperature, the plastic raw material has fluidity in the second operation (operation S2).

[0055] The method of manufacturing a plastic lens according to one or more embodiments includes a third operation (operation S3). The third operation (operation S3) may be an operation of pressing a plastic raw material.

[0056] The plastic raw material may be pressed while heating the plastic raw material to a temperature higher than the glass transition temperature of the plastic raw material.

[0057] Since the plastic raw material is heated to have fluidity, the plastic raw material can be pressed and molded into a shape corresponding to the shape of the cavity.

[0058] exist Figure 1 , the third operation (operation S3) is shown as being performed after the second operation (operation S2). However, in order to shorten the cycle of the lens manufacturing process, the second operation (operation S2) and the third operation (operation S3) may be performed simultaneously.

[0059] Since the total weight of the plastic raw material is greater than the weight of the lens to be manufactured, a portion of the plastic raw material may be discharged from the cavity when the plastic raw material is pressed by the mold.

[0060] The method of manufacturing a plastic lens according to one or more embodiments includes a fourth operation (operation S4). The fourth operation (operation S4) may be an operation of cooling the mold.

[0061] In the fourth operation (operation S4), the mold may be cooled to below the glass transition temperature. Therefore, the lens molded in the cavity of the mold may also be cooled.

[0062] The method of manufacturing a plastic lens according to one or more embodiments includes a fifth operation (operation S5). The fifth operation (operation S5) may be an operation of separating the lens from the mold.

[0063] In a fifth operation (operation S5), the molded lens may be separated from the mold and stored separately.

[0064] The method of manufacturing a plastic lens according to one or more embodiments may include a sixth operation (operation S6) that may be an operation of removing a portion (burr) of the plastic raw material discharged to the outside of the cavity in the third operation (operation S3) from the mold.

[0065] Figure 2 The raw plastic material is shown positioned in the second mold. Figure 3 The first mold is shown moving. Figure 4 An example is shown in which a plastic raw material is heated and pressed by a mold. Figure 5 Shows Figure 4 Magnified view of part A.

[0066] in addition, Figure 6 An example in which a molded lens is separated from a mold is shown, and Figure 7 An example is shown in which a plastic raw material discharged to the outside of a cavity during a lens molding process is removed from a mold.

[0067] Reference Figures 2 to 7 , the manufacturing process of the plastic lens L and the manufacturing mold (or die) 1 will be described in detail.

[0068] First, refer to Figure 2 and Figure 3 , the mold 1 includes a first mold 10, a second mold 20, and a third mold 30. The first mold 10 may be a movable mold, and the second mold 20 and the third mold 30 may be fixed molds.

[0069] The first mold 10 includes a first core part 11 and a first body part 13. The first body part 13 is provided with an accommodation space accommodating the first core part 11 therein, and in an example, the accommodation space may be in the shape of a hole or a concave part.

[0070] The first core part 11 is accommodated in the first body part 13. One surface 11a of the first core part 11 may have a shape corresponding to the shape of the plastic lens L to be manufactured.

[0071] In an example, one surface 11 a of the first core portion 11 may have a shape corresponding to the object-side surface of the plastic lens L being manufactured.

[0072] The second mold 20 includes a second core part 21 and a second body part 23. The second body part 23 has an accommodation space for accommodating the second core part 21 therein, and in an example, the accommodation space may be in the shape of a hole or a concave part.

[0073] The second core part 21 is accommodated in the second body part 23. One surface 21a of the second core part 21 may have a shape corresponding to the shape of the plastic lens L being manufactured.

[0074] In an example, one surface 21 a of the second core portion 21 may have a shape corresponding to the image side surface of the plastic lens L being manufactured.

[0075] The first body part 13 and the second body part 23 may be disposed to face each other, and the first core part 11 and the second core part 21 may be disposed to face each other.

[0076] One surface 21 a of the second core part 21 may be located below one surface 23 a of the second body part 23 facing the first body part 13 .

[0077] The third mold 30 includes a third body part 31. The third body part 31 is coupled to one surface 23a of the second body part 23 facing the first body part 13.

[0078] When the first mold 10 moves and engages with the second mold 20 and the third mold 30, a cavity C surrounded by the first mold 10, the second mold 20, and the third mold 30 may be formed. For example, a space surrounded by one surface 11a of the first core portion 11, one surface 21a of the second core portion 21, an inner surface of the second body portion 23, and an inner surface of the third body portion 31 may define the cavity C.

[0079] The cavity C may be a space in which the plastic lens L is molded.

[0080] The plastic raw material P is set in the mold 1. Here, in the example, the plastic raw material P may be a material for manufacturing the plastic lens L, and may be a thermoplastic resin material. In the example, the plastic raw material P may be a resin material in the form of pellets.

[0081] The weight of the plastic raw material P may be greater than the weight of the plastic lens L to be manufactured.

[0082] The plastic raw material P may be placed on one surface 21 a of a second core portion 21 of a second mold 20 , which is a fixed mold.

[0083] When the plastic raw material P is placed in the second core portion 21 of the second mold 20, the plastic raw material P is heated by the second mold 20. For example, the plastic raw material P may be heated to a temperature higher than the glass transition temperature of the plastic raw material P.

[0084] Therefore, the heating unit 40 generating heat may be respectively provided in the first mold 10 and the second mold 20. The heating unit 40 includes a first heating unit 41 heating the first body part 13 and the second body part 23. In addition, the heating unit 40 may include a second heating unit 43 heating the first core part 11 and the second core part 21.

[0085] The mold 1 may be equipped with a temperature sensor, and the temperature of the mold 1 (or the temperature of the plastic raw material P) may be measured by the temperature sensor.

[0086] The first heating unit 41 may be disposed on the first body part 13 and the second body part 23 to heat the respective first body part 13 and the second body part 23. Therefore, the first core part 11 accommodated in the first body part 13 and the second core part 21 accommodated in the second body part 23 may also be heated. That is, the first heating unit 41 may indirectly heat the first core part 11 and the second core part 21.

[0087] The second heating unit 43 may be disposed at a position where the first core part 11 and the second core part 21 are heated. The second heating unit 43 may be disposed around the first core part 11 and around the second core part 21.

[0088] For example, the second heating unit 43 may be disposed in the upper portion of the first core portion 11 and in the lower portion of the second core portion 21. In an example, the upper portion of the first core portion 11 may refer to an opposite side of one surface 11a of the first core portion 11, and the lower portion of the second core portion 21 may refer to an opposite side of one surface 21a of the second core portion 21.

[0089] In an example, before the plastic raw material P is placed on the second core portion 21 , the second core portion 21 may be pre-heated by one or more of the first heating unit 41 and the second heating unit 43 .

[0090] Therefore, since the heating time for the plastic raw material P to become fluid can be shortened, the manufacturing time of the plastic lens L can be shortened, and the productivity can be improved.

[0091] In addition, the first core portion 11 may also be preheated by one or more of the first heating unit 41 and the second heating unit 43 .

[0092] Reference Figures 3 to 5 , the first mold 10 can move and engage with the second mold 20 and the third mold 30. The first mold 10 as a movable mold moves toward the second mold 20 and the third mold 30 as fixed molds, and a cavity C is formed between the movable mold 10 and the fixed molds 20 and 30.

[0093] The cavity C may be defined as a space surrounded by the first core portion 11 of the first mold 10 , the second core portion 21 of the second mold 20 , the inner surface of the second body portion 23 of the second mold 20 , and the inner surface of the third body portion 31 of the third mold 30 .

[0094] When the first mold 10 moves, the plastic raw material P disposed in the second core part 21 of the second mold 20 can be pressed. At this time, the plastic raw material P can be heated by the first mold 10 and the second mold 20 to have fluidity, so that the plastic raw material P can be pressed according to the shape of the cavity C.

[0095] In an example, since the weight of the plastic raw material P may be greater than the weight of the plastic lens L to be manufactured, the excess weight should be discharged to the outside of the cavity C.

[0096] In the example, the first mold 10 moves to a position closer to one surface 23 a of the second body portion 23 than one surface 31 a of the third body portion 31 facing the first body portion 13 .

[0097] In an example in which the first mold 10 is engaged with the second mold 20 and the third mold 30 , one surface 11a of the first core portion 11 of the first mold 10 is located between one surface 23a of the second body portion 23 of the second mold 20 and one surface 31a of the third body portion 31 .

[0098] The third mold 30 may have one or more recessed portions 33 having one surface 31a of the third body portion 31 facing the first body portion 13 as a bottom surface. The one or more recessed portions 33 may be open toward the second core portion 21.

[0099] In an example in which the first mold 10 is engaged with the second mold 20 and the third mold 30 , the side surface of the first core portion 11 of the first mold 10 is in contact with the inner surface of the third body portion 31 .

[0100] Therefore, when the first mold 10 moves, a portion B of the plastic raw material P that exceeds the weight of the plastic lens L to be manufactured is discharged to the outside of the cavity C through the one or more concave portions 33 .

[0101] In addition, when a surface 11a of the first core portion 11 of the first mold 10 moves downward relative to a surface 31a of the third body portion 31, the plastic raw material P disposed in the cavity C and a portion B of the plastic raw material P discharged to the outside of the cavity C are separated from each other.

[0102] Reference Figure 5 In an example in which the first mold 10 is engaged with the second mold 20 and the third mold 30, a distance T1 between an outer end of a surface 11a of the first core portion 11 and an outer end of a surface 21a of the second core portion 21 may be smaller than a distance T2 between an outer end of a surface 21a of the second core portion 21 and a surface 31a of the third body portion 31.

[0103] In an example, 0.1≤T1 / T2<1 may be satisfied.

[0104] When the molding of the plastic lens L is completed, the mold 1 can be cooled. In an example, the mold 1 can be cooled below the glass transition temperature. Therefore, the plastic lens L molded in the cavity C of the mold 1 can also be cooled. When the cooling is completed, the first mold 10 is separated from the second mold 20 and the third mold 30.

[0105] The cooling of the mold 1 can be achieved by supplying a fluid into the mold 1. In a non-limiting example, the fluid can be air or water. Therefore, a flow path for cooling the mold 1 can be provided in the mold 1. In an example, the flow path can be provided in the first body portion 13 of the first mold 10 and the second body portion 23 of the second mold 20.

[0106] Thereafter, the molded plastic lens L may be removed from the mold 1 and stored separately, and when the removal of the plastic lens L is completed, the portion B of the plastic raw material P filling the one or more concave portions 33 may be removed from the mold 1 .

[0107] FIG. 8A to FIG. 8D are plan views of various examples of the second mold and the third mold, and 9A to 9C are cross-sectional views of various examples of the concave portion.

[0108] Reference FIG. 8A to FIG. 8D , one or more recessed portions 33 are formed in the third body portion 31, and upper portions and sides of the recessed portions 33 may be open.

[0109] In an example, an upper portion of the recessed portion 33 may be opened toward the first body portion 13 , and one side portion of the recessed portion 33 may be opened toward the second core portion 21 .

[0110] When a plurality of recessed portions 33 are provided, the plurality of recessed portions 33 may be provided to be spaced apart from each other along the circumference of the second core portion 21 .

[0111] Reference 9A to 9C , the concave portion 33 can accommodate a portion B of the plastic raw material P discharged to the outside of the cavity C when the plastic raw material P is pressed.

[0112] In an example, the lower width (or volume) of the concave portion 33 may be equal to or smaller than the upper width (or volume) of the concave portion 33. In an example, the width of the concave portion 33 may increase linearly or nonlinearly from the bottom of the concave portion 33 to the top of the concave portion 33.

[0113] When the lower width of the recessed portion 33 is smaller than the upper width of the recessed portion 33, as the first mold 10 moves to press the plastic raw material P, the amount of the plastic raw material P discharged to the outside of the cavity C can be reduced, which is beneficial for precise weight control of the plastic lens L.

[0114] The plastic lens L according to one or more embodiments may be formed of plastic, and may be manufactured by a heating and pressing method rather than a conventional injection molding method.

[0115] Generally, when a lens is manufactured by injection molding, residual stress may occur in a gate portion as a passage for molten resin, which may lead to deterioration of optical performance. In addition, since the gate should be removed from the injection molded lens, the manufacturing process may increase, and there is a risk that the lens may be damaged during the gate removal process.

[0116] In addition, since the lens may have a curved shape rather than a flat shape, there is a variation in the thickness of each portion of the cavity of the injection mold. Therefore, there is a difference in the rate at which the molten resin flows, which can cause flow marks or weld lines in the injection molded lens, resulting in degradation of optical performance.

[0117] However, since the plastic lens L according to one or more embodiments is manufactured by heating and pressing the plastic raw material P in a pellet state, problems occurring during injection molding may be solved.

[0118] In an example, the plastic lens L according to one or more embodiments may prevent the generation of flow marks and welding lines, and may also prevent degradation of optical properties (eg, high birefringence) due to residual stress.

[0119] Fig.10 is a plan view of an exemplary plastic lens according to one or more embodiments, and Fig.11 is a perspective view of an exemplary plastic lens according to one or more embodiments.

[0120] Reference Fig.10 and Fig.11 , the plastic lens L according to one or more embodiments includes an optical portion EA and a flange portion FA. The optical portion EA may be a portion in which optical properties of the plastic lens L are displayed. In an example, light reflected from an object may be refracted while passing through the optical portion EA.

[0121] In an example, the plastic lens L according to one or more embodiments may have a diameter of 10 mm or more. In an example, the diameter may be a total diameter of the plastic lens L including the optical portion EA and the flange portion FA.

[0122] The optical portion EA may have refractive power and may have an aspherical shape.

[0123] In addition, the optical portion EA includes an object-side surface (a surface facing the object side) and an image-side surface (a surface facing the image side).

[0124] The plastic lens L may have different thicknesses for each portion of the plastic lens L. In an example, the object-side surface and the image-side surface of the optical portion EA may have different curvatures. In an example, the thickness refers to the thickness in the optical axis direction.

[0125] The ratio between the thickest part and the thinnest part of the optical part EA of the plastic lens L according to one or more embodiments may be 3.0 or greater. For example, T_max / T_min≥3.0. Here, T_max represents the maximum thickness of the optical part EA, and T_min represents the minimum thickness of the optical part EA.

[0126] The flange portion FA may be a portion that fixes the plastic lens L to another component (eg, a lens barrel or another lens).

[0127] The flange portion FA may extend from the optical portion EA and may be integrally formed with the optical portion EA.

[0128] When the plastic lens L is manufactured by injection molding, the manufactured plastic lens L may have problems such as flow marks and weld lines or high birefringence.

[0129] However, since the plastic lens L according to one or more embodiments is manufactured by heating and pressing the plastic raw material P in the form of pellets, it is possible to prevent the deterioration of optical properties (occurrence of flow marks and weld lines, high birefringence, etc.) that occurs in existing plastic injection-molded lenses. Therefore, the optical properties can be improved.

[0130] During the manufacturing of the plastic lens L, as the plastic raw material P is pressed in the mold 1, a portion B of the plastic raw material P is discharged outside the cavity C. Then, the plastic raw material P discharged outside by the movement of the first mold 10 is cut from the plastic lens L.

[0131] Therefore, the plastic lens L has one or more cutting portions LC at the edge of the flange portion FA. The cutting portions LC are formed at positions where the plastic raw material P is separated.

[0132] The cut portion LC may have greater birefringence than other portions of the flange portion FA. In an example, the birefringence of the cut portion LC may be greater than that of other portions of the edge of the flange portion FA.

[0133] However, the birefringence of the cut portion LC may be significantly smaller than the birefringence of the gate portion of a general plastic injection-molded lens.

[0134] When a plurality of cutting portions LC are provided, the plurality of cutting portions LC may be spaced apart from each other along the circumference of the flange portion FA.

[0135] In an example, the parting line PL may be continuously formed along the circumference of the flange portion FA on the side surface of the flange portion FA of the plastic lens L. The parting line PL may be a shape formed by surfaces of different molds contacting each other.

[0136] In the example, refer to Figure 5 , a side surface of the flange portion FA of the plastic lens L may correspond to an inner surface of the second body portion 23 of the second mold 20 and an inner surface of the third body portion 31 of the third mold 30 .

[0137] Therefore, the profile line PL may be continuously formed along the circumference of the flange portion FA on a side surface of the flange portion FA corresponding to a portion where the second body portion 23 and the third body portion 31 contact each other.

[0138] According to the plastic lens and the molding apparatus for manufacturing the plastic lens according to one or more embodiments, the optical properties of the plastic lens may be improved.

[0139] Although specific examples have been shown and described above, it will be apparent after understanding the present disclosure that various changes in form and detail may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are considered to be illustrative only and not for limiting purposes. The description of the features or aspects in each example is considered to be applicable to similar features or aspects in other examples. Suitable results may also be obtained if the described techniques are performed in a different order, and / or if the components in the described systems, architectures, devices, or circuits are combined in different ways and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of the present disclosure is not limited by specific embodiments, but by the claims and their equivalents, and all changes within the scope of the claims and their equivalents will be interpreted as included in the present disclosure.

Claims

1. A plastic lens, comprising: Optical part, refracting light; as well as a flange portion extending from the optical portion, Wherein, a profile line is continuously formed on a side surface of the flange portion along a circumference of the flange portion.

2. The plastic lens according to claim 1, wherein T_max / T_min≥3.0, wherein T_max is the maximum thickness of the optical portion, and T_min is the minimum thickness of the optical portion.

3. The plastic lens according to claim 1, wherein The diameter of the plastic lens is 10 mm or more.

4. The plastic lens according to claim 1, wherein: one or more cutting portions are provided on an edge of the flange portion, and The one or more cut portions have a greater birefringence than other portions of the edge of the flange portion.

5. The plastic lens according to claim 4, wherein: A plurality of cutting portions are provided and are spaced apart from each other along a circumference of the flange portion.

6. A molding device for manufacturing a plastic lens, the molding device comprising: A first mold, comprising a first core portion and a first body portion accommodating the first core portion; A second mold, comprising a second core portion and a second body portion accommodating the second core portion; as well as a third mold including a third body portion coupled to a first surface of the second body portion facing the first body portion, wherein the first mold is configured to be movable relative to the second mold and the third mold, wherein the first mold is configured to move to a position closer to the first surface of the second body portion than to a first surface of the third body portion facing the first body portion, and When the first mold moves, a cavity surrounded by the first core portion, the second core portion, the second body portion, and the third body portion is formed.

7. The molding apparatus according to claim 6, wherein: The third body portion includes one or more recessed portions, and the first surface of the third body portion is a bottom surface of the one or more recessed portions.

8. The molding apparatus according to claim 7, wherein: The one or more concave portions are provided in plural, and the plurality of concave portions are spaced apart from each other in a circumferential direction.

9. The molding apparatus according to claim 7, wherein: the first surface of the second core portion is located at a lower position than the first surface of the second body portion, and A first surface of the first core portion that faces the first surface of the second core portion is configured to move to be located between the first surface of the second body portion and the first surface of the third body portion.

10. The molding apparatus according to claim 9, wherein: When forming the cavity, a distance between an outer end of the first surface of the first core portion and an outer end of the first surface of the second core portion is smaller than a distance between an outer end of the first surface of the second core portion and the first surface of the third body portion.

11. The molding apparatus according to claim 10, wherein: 0.1≤T1 / T2<1 is satisfied, wherein T1 is the distance between the outer end of the first surface of the first core part and the outer end of the first surface of the second core part, and T2 is the distance between the outer end of the first surface of the second core part and the first surface of the third main body part.

12. The molding apparatus according to claim 7, wherein: The one or more concave portions are formed to have a larger volume at an upper end of the one or more concave portions than at a lower end of the one or more concave portions.

13. The molding apparatus according to claim 6, wherein: The first body portion and the second body portion are each provided with a first heating unit configured to generate heat and a flow path through which a fluid flows.

14. The molding apparatus according to claim 13, wherein: A second heating unit configured to generate heat is coupled to each of the first core portion and the second core portion.

15. A molding device for manufacturing a plastic lens, the molding device comprising: A first movable mold including a first core portion and a first body portion accommodating the first core portion; A second mold, comprising a second core portion and a second body portion accommodating the second core portion; as well as a third mold including one or more concave portions and a third body portion coupled to a first surface of the second body portion facing the first body portion, wherein, based on the movement of the first mold toward the second mold, a cavity is formed between the first mold and the second mold, and the cavity is configured to accommodate a raw material, and Wherein, when the first mold moves toward the second mold, a portion of the raw material exceeding the weight of the plastic lens is discharged from the mold cavity into the one or more concave portions.

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