Optical lens and camera module including the same

Abstract

The optical lens includes at least one straight portion and one curved portion on the outer surface, and an apodization area for reducing flare is disposed at an edge adjacent to the straight portion.

Description

[Technical Field]

[0001] The present embodiment relates to an optical lens and a camera module including the same. [Background technology]

[0002] In recent years, ultra-miniature cameras have become widely used in portable devices, and these cameras include the capability to capture not only digital images but also video.

[0003] The camera module includes an image sensor, a lens barrel that houses a camera lens facing the image sensor, a voice coil motor (VCM) that narrows or widens the gap between the camera lens and the image sensor, and an aperture.

[0004] A camera lens typically includes three or four overlapping optical lenses.

[0005] At least one of the optical lenses may be a D-cut lens having a straight portion cut on one side.

[0006] FIG. 1 is a cross-sectional view of a conventional D-cut lens, and FIG. 2 is a diagram illustrating an image measured through the D-cut lens of FIG.

[0007] 1 and 2, a conventional D-cut lens 10 may have a straight portion 12 cut on one side. In one example, the D-cut lens 10 may include a plurality of curved portions 14 facing each other and a plurality of straight portions 12 facing each other. The straight portions 12 may be formed by cutting a portion of a circular lens.

[0008] In a camera module using a prism or a mirror, the above-described deep cut lens may be applied to at least one of a plurality of optical lenses in order to reduce the height or Fno of the module.

[0009] However, as shown in Figure 2, due to the shape of the D-cut lens itself, there is a problem in that flare and ghosting occur when light is reflected through the D-cut lens. Summary of the Invention [Problem to be solved by the invention]

[0010] The present embodiment aims to provide an optical lens and a camera module including the same that can reduce the occurrence of flare or ghosting by improving the structure. [Means for solving the problem]

[0011] In one embodiment, the optical lens includes at least one straight portion and one curved portion on an outer surface, and an apodization area for reducing flare is disposed at an edge adjacent to the straight portion.

[0012] The apodization region may include a plurality of regions with different light transmittances.

[0013] The apodization region may be formed so that light transmittance decreases toward the edge.

[0014] The apodization region is a region where ink is coated on the surface, and the thickness of the coating region may increase toward the edge.

[0015] The apodization region is a region in which a number of patterns are arranged spaced apart from one another, and the cross-sectional shape of the patterns may include any one of a circle, an ellipse, and a polygon.

[0016] The pattern may be formed so that its size increases toward the edge.

[0017] The closer to the edge of the optical lens, the closer the spacing between adjacent patterns may be.

[0018] The linear portions may be provided in a plurality of numbers and arranged to face each other with respect to the center, and the curved portions may be provided in a plurality of numbers and arranged to face each other with respect to the center.

[0019] When the linear distance between the linear portions is A and the thickness of the apodization region defined in a direction perpendicular to the linear portions is C, the relationship may be 0.05*A≦C≦0.5*A.

[0020] When the linear distance between the plurality of linear portions is A and the maximum linear distance between the plurality of curved portions is B, A=α*B, (0.3≦α≦0.9). [Effects of the Invention]

[0021] This embodiment has the advantage of being able to reduce flare and ghosting due to the diffractive effect of the apodization area at the edge area of ​​the optical lens. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a cross-sectional view of a conventional D-cut lens. [Figure 2] 2 is a diagram illustrating an image measured through the D-cut lens of FIG. 1; [Figure 3] 1 is a cross-sectional view of an optical lens according to an embodiment of the present invention. [Figure 4] 1 is a diagram illustrating an image measured through an optical lens according to an embodiment of the present invention. [Figure 5] 1 is a graph illustrating transmittance at various positions in an optical lens according to an embodiment of the present invention. [Figure 6] FIG. 2 is an enlarged view of an apodization region in an optical lens according to an embodiment of the present invention. [Figure 7] 10 is a diagram illustrating a modified example of an apodization region according to an embodiment of the present invention. [Figure 8]4 is a diagram illustrating light transmittance according to the arrangement structure of an apodization region in an optical lens according to an embodiment of the present invention. [Figure 9] 4 is a diagram illustrating light transmittance according to the arrangement structure of an apodization region in an optical lens according to an embodiment of the present invention. [Figure 10] 4 is a diagram illustrating light transmittance according to the arrangement structure of an apodization region in an optical lens according to an embodiment of the present invention. [Figure 11] 4 is a diagram illustrating light transmittance according to the arrangement structure of an apodization region in an optical lens according to an embodiment of the present invention. [Figure 12] 4 is a diagram illustrating light transmittance according to the arrangement structure of an apodization region in an optical lens according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0024] However, the technical concept of the present invention is not limited to the described embodiments and can be embodied in various different forms, and one or more of the components of the embodiments can be selectively combined or substituted within the scope of the technical concept of the present invention.

[0025] Furthermore, unless otherwise clearly and specifically defined, terms (including technical and scientific terms) used in the embodiments of the present invention shall be interpreted as meanings that are commonly understood by a person of ordinary skill in the art to which the present invention belongs, and commonly used terms such as predefined terms shall be interpreted in light of the contextual meaning of the relevant art.

[0026] Furthermore, the terms used in the examples of the present invention are intended to describe the examples and are not intended to limit the present invention. In this specification, the singular can include the plural unless otherwise specified in the context, and when it is stated as "A and (and) at least one (or more) of B and C," it can include one or more of all possible combinations of A, B, and C.

[0027] Additionally, terms such as first, second, A, B, (a), (b), etc. may be used to describe components of embodiments of the present invention.

[0028] Such terms are used only to distinguish one component from another, and are not intended to limit the nature, order, or sequence of the components.

[0029] Furthermore, when a component is described as being 'coupled', 'coupled' or 'connected' to another component, it includes not only the case where the component is directly coupled, coupled or connected to the other component, but also the case where the component is 'coupled', 'coupled' or 'connected' by another component between the component and the other component.

[0030] Furthermore, when describing something as being formed or disposed "above (above) or below (below)" each component, "above (above) or below (below)" includes not only cases where two components are in direct contact with each other, but also cases where one or more additional components are formed or disposed between the two components. Furthermore, when expressed as "above (above) or below (below)," it can mean not only the upper direction but also the lower direction based on one component.

[0031] FIG. 3 is a cross-sectional view of an optical lens according to an embodiment of the present invention, FIG. 4 is a diagram illustrating an image measured through an optical lens according to an embodiment of the present invention, FIG. 5 is a graph illustrating the transmittance at various positions in an optical lens according to an embodiment of the present invention, and FIG. 6 is an enlarged view of an apodization region in an optical lens according to an embodiment of the present invention.

[0032] 3 to 5, an optical lens 100 according to an embodiment of the present invention may be a deep-cut lens. The optical lens 100 may include at least one curved portion 110 and at least one straight portion 120. The optical lens 100 may have a circular shape with one side cut out. The cutout region may form the straight portion 120.

[0033] The curved portion 110 may have an end formed in a curved shape. The straight portion 120 may have an end formed in a straight shape. The curved portion 110 and the straight portion 120 may be disposed in a frame region of the optical lens 110. A plurality of the curved portions 110 may be provided and disposed to face each other. A plurality of the straight portions 120 may be provided and disposed to face each other. The curved portion 110 and the straight portion 120 may be disposed adjacent to each other. The outer surface of the optical lens 110 may have a shape in which the curved portions 110 and the straight portions 120 are alternately disposed.

[0034] The length of the straight portion 120 may be longer than the length of the curved portion 110. Alternatively, the length of the curved portion 110 may be longer than the length of the straight portion 120.

[0035] The optical lens 110 may include an apodization region 140. The apodization region 140 may be formed on the surface of the optical lens 110. The apodization region 140 may be disposed on the entrance surface or exit surface of the optical lens 110. The apodization region 140 may be disposed on the edge of the optical lens 110.

[0036] The apodization region 140 may be disposed in an end region of the optical lens 110 adjacent to the linear portion 120. The apodization region 140 may be disposed inside the linear portion 120. When a plurality of linear portions 120 are provided, the apodization regions 140 may be provided in plurality and disposed to face each other with respect to the center of the optical lens 110.

[0037] In some cases, at least a portion of the apodization region 140 may be disposed inside the curved portion 110. That is, the center portion of the apodization region 140 may be disposed inside the straight portion 120, and both ends may be disposed inside the curved portion 110.

[0038] The apodization region 140 may have a predetermined thickness based on the height of the optical lens 110. Here, the height of the optical lens 110 may be defined as the vertical length between the plurality of linear portions 120.

[0039] 6, the apodization region 140 may include a plurality of regions having different light transmittances. The apodization region 140 may be formed such that the light transmittance decreases toward the edge of the optical lens 110.

[0040] The apodization region 140 is a treatment for reducing higher-order diffraction images, and may reduce the diffraction effect at the edge region of the optical lens 110. The apodization region 140 may be a coating treatment on the surface of the optical lens 110. The apodization region 140 may be a region where ink is coated on the surface of the optical lens 110. To form the apodization region 140 as shown in FIG. 6, the coating region may be formed to be thicker toward the edge of the optical lens 110. Furthermore, the apodization region 140 may be coated with ink of a darker series toward the edge of the optical lens 110.

[0041] Meanwhile, the apodization region 140 may be implemented using a separate device attached to the surface of the optical lens 110. For example, the separate device may include a spacer.

[0042] According to the above structure, as shown in FIG. 4, flare caused by diffraction effect at the edge region of the optical lens 100 can be reduced.

[0043] 5, it is possible to prevent a sudden change in light transmittance at the end region (the region where the straight portion 120 is arranged) of the optical lens 100. In other words, the apodization region 140 reduces the Airy Disk size of the optical lens 100, thereby reducing the diffraction effect.

[0044] FIG. 7 is a diagram illustrating a modified example of the apodization region according to an embodiment of the present invention.

[0045] 7, the apodization region 140 may be a region in which a number of patterns 180 are combined. The cross-sectional shape of the patterns 180 may be any of a circle, an ellipse, and a polygon. The patterns 180 may be formed to be larger toward the edge of the optical lens 100. Also, the spacing between adjacent patterns 180 may be closer toward the edge of the optical lens 100.

[0046] 8 to 12 are diagrams illustrating light transmittance according to the arrangement structure of the apodization region in the optical lens according to the embodiment of the present invention.

[0047] Referring to FIG. 8, the lengths of the optical lens 100 by region can be defined as follows. A: The distance between the multiple straight sections (120mm) (optical lens size) B: Maximum straight-line distance between multiple curved sections 110 (effective diameter of optical lens) C: Thickness of the apodization region 140 measured in a direction perpendicular to the straight portion 120

[0048] Referring to Figure 9, when the transmittance in the central region of the optical lens 100 excluding the apodization region 140 is set to 1 and the transmittance in the region other than the optical lens 100 is set to 0, it can be seen that the light transmittance in the apodization region 140 continuously decreases or increases, as described above.

[0049] 10, which illustrates the brightness ratio of the optical lens 100 according to the magnitude of C, it can be seen that when the thickness of the apodization region 140 satisfies the range of 0.05*A≦C≦0.5*A, flare can be prevented while maintaining brightness within a desired range. The simulation results for the optical lens 100 according to the above-described range of C are shown in FIG. 11. That is, when the thickness of the apodization region 140 is increased more than necessary, the light transmittance of the optical lens 100 drops significantly, and therefore, the flare prevention range taking light transmittance into consideration is as described above.

[0050] Furthermore, the linear distance A between the plurality of linear portions 120 and the maximum linear distance B between the plurality of curved portions 110 can satisfy the following relational expression.

[0051] A=α*B(0.3≦α≦0.9)

[0052] Here, α may be a D-cut ratio. That is, when α is within the above range, the optical lens 100 has a satisfactory brightness ratio compared to a normal lens having a diameter A (see FIG. 12 ). Therefore, the linear distance A between the plurality of linear portions 120 and the maximum linear distance B between the plurality of curved portions 110 may have the above-mentioned relationship.

[0053] Although all components constituting the embodiments of the present invention have been described above as being combined or operating in combination, the present invention is not necessarily limited to such embodiments. That is, all components may be selectively combined and operate in combination, within the scope of the present invention. Furthermore, unless otherwise specified, the terms "comprise," "comprise," "have," etc., used above mean that the corresponding component may be present, and should be interpreted as including other components, not excluding other components. All terms, including technical and scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the present invention pertains, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted in accordance with the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0054] The above description merely illustrates the technical concept of the present invention, and various modifications and variations may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed herein are for illustrative purposes only and are not intended to limit the technical concept of the present invention. The scope of the present invention should be interpreted by the following claims, and all technical concepts within the scope equivalent thereto should be construed as being within the scope of the present invention.

Claims

1. An optical lens having an outer surface including a plurality of straight portions and a plurality of curved portions, an apodization region for reducing flare is disposed at an end adjacent to the linear portion; The plurality of linear portions are arranged to face each other with respect to a center, a plurality of apodization regions are provided, each of which is disposed on each of the plurality of linear portions; The plurality of curved portions are arranged to face each other with respect to a center, both ends of the apodization regions arranged in each of the linear portions are arranged inside the curved portion, The length of the straight portion is longer than the length of the curved portion, If the linear distance between the plurality of linear portions is A and the maximum linear distance between the plurality of curved portions is B, then A=α*B, (0.3≦α≦0.9), B is the effective diameter of the optical lens, When the linear distance between the plurality of linear portions is A and the thickness of the apodization region defined in a direction perpendicular to the linear portions is C, An optical lens in which 0.05*A≦C≦0.5*A.

2. The optical lens according to claim 1 , wherein the apodization region includes a plurality of regions having different light transmittances.

3. The optical lens according to claim 2 , wherein the apodization region is formed so that light transmittance decreases toward the edge.

4. The apodization area is an area where ink is coated on the surface, The optical lens of claim 1 , wherein the coated area has an increased thickness towards the edges.

5. The apodization region is a region in which a number of patterns are arranged spaced apart from one another, The optical lens according to claim 1 , wherein the cross-sectional shape of the pattern includes any one of a circle, an ellipse, and a polygon.

6. The optical lens according to claim 5 , wherein the pattern is formed so that the size of the pattern increases toward the edge.

7. The optical lens according to claim 5 , wherein the spacing between adjacent patterns is closer to the edge of the optical lens.

8. An image sensor and an optical lens facing the image sensor and including a plurality of straight lines and a plurality of curved lines on its outer surface; a lens barrel that houses the optical lens; an apodization region for reducing flare is disposed at an end adjacent to the linear portion; The plurality of linear portions are arranged to face each other with respect to a center, a plurality of apodization regions are provided, each of which is disposed on each of the plurality of linear portions; The plurality of curved portions are arranged to face each other with respect to a center, both ends of the apodization regions arranged in each of the linear portions are arranged inside the curved portion, The length of the straight portion is longer than the length of the curved portion, If the linear distance between the plurality of linear portions is A and the maximum linear distance between the plurality of curved portions is B, then A=α*B, (0.3≦α≦0.9), B is the effective diameter of the optical lens, When the linear distance between the plurality of linear portions is A and the thickness of the apodization region defined in a direction perpendicular to the linear portions is C, A camera module in which 0.05*A≦C≦0.5*A.

Images