Optical imaging system

Abstract

An optical imaging system is provided. The optical imaging system includes, arranged in order from an object side to an imaging side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens, wherein the first lens has a positive refractive power and the second lens has a negative refractive power, wherein at least one of the first lens to the eighth lens is formed of glass and the remaining lenses are formed of plastic, and a condition of TTL / (2xIMG HT) < 0.6 is satisfied, wherein TTL represents a distance on an optical axis from an object side surface of the first lens to an imaging surface, and IMG HT represents half of a diagonal length of the imaging surface.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2021-0175111, filed on December 8, 2021, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] The following description relates to optical imaging systems. Background Technology

[0004] Recently, portable terminals have been equipped with cameras, including optical imaging systems with multiple lenses, for purposes such as video calling and image capture.

[0005] Furthermore, as the functions implemented by cameras in portable terminals gradually increase, the demand for high-resolution cameras in portable terminals is growing.

[0006] Specifically, the latest cameras implemented in portable terminals may include image sensors with a high pixel count (e.g., 13 to 100 million pixels) in order to achieve clearer image quality.

[0007] Furthermore, since the form factor of portable devices has become smaller, it may be advantageous for cameras implemented in portable devices to also have a slim form factor. Therefore, it may also be beneficial to achieve an optical imaging system with high resolution and a slim form factor.

[0008] The above information is presented as background information only to aid in understanding this disclosure. No determination is made, and no assertion is made, regarding whether any of the above items can be used as prior art relative to this disclosure. Summary of the Invention

[0009] The summary portion of this invention is intended to provide a brief overview of the chosen inventive concepts, which will be further described in the detailed description portion below. This summary portion is not intended to identify key or essential features of the claimed subject matter, nor to help determine the scope of the claimed subject matter.

[0010] In a general aspect, an optical imaging system includes, arranged in order from an object side to an imaging side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens, wherein the first lens has a positive refractive power, and the second lens has a negative refractive power, wherein at least one lens among the first lens to the eighth lens is formed of glass, and the remaining lenses are formed of plastic, and wherein TTL / (2xIMG HT)<0.6 is satisfied, where TTL denotes a distance on an optical axis from an object side surface of the first lens to an imaging surface, and IMG HT denotes half of a diagonal length of the imaging surface.

[0011] At least one of -0.2<SAG52 / TTL<0, -0.2<SAG62 / TTL<0, -0.3<SAG72 / TTL<0, and -0.3<SAG82 / TTL<0 can be satisfied, where SAG52 denotes a SAG value obtained at an end of an effective diameter of an image side surface of the fifth lens, SAG62 denotes a SAG value obtained at an end of an effective diameter of an image side surface of the sixth lens, SAG72 denotes a SAG value obtained at an end of an effective diameter of an image side surface of the seventh lens, and SAG82 denotes a SAG value obtained at an end of an effective diameter of an image side surface of the eighth lens.

[0012] At least one of 40<v1-v2<70, 30<v1-v4<70, and 20<v1-(v6+v7) / 2<50 can be satisfied, where v1 denotes an Abbe number of the first lens, v2 denotes an Abbe number of the second lens, v4 denotes an Abbe number of the fourth lens, v6 denotes an Abbe number of the sixth lens, and v7 denotes an Abbe number of the seventh lens.

[0013] The first lens can be formed of glass having an Abbe number greater than 70.

[0014] An Abbe number of the first lens can be the largest among Abbe numbers of the first lens to the eighth lens, and the second lens and the fourth lens can each be formed of one of glass and plastic having a refractive index greater than 1.65 and an Abbe number less than 22.

[0015] 0<f1 / f<1.4 can be satisfied, where f denotes a total focal length of the optical imaging system, and f1 denotes a focal length of the first lens.

[0016] -10<f2 / f<-1 can be satisfied, where f denotes a total focal length of the optical imaging system, and f2 denotes a focal length of the second lens.

[0017] 0<|f3 / f| / 10<30 can be satisfied, where f denotes a total focal length of the optical imaging system, and f3 denotes a focal length of the third lens.

[0018] 0.5<|f6 / f|<10 can be satisfied, where f denotes a total focal length of the optical imaging system, and f6 denotes a focal length of the sixth lens.

[0019] -3<f8 / f<0 can be satisfied, where f denotes a total focal length of the optical imaging system, and f8 denotes a focal length of the eighth lens.

[0020] TTL / f<1.4 and BFL / f<0.3 can be satisfied, where f denotes a total focal length of the optical imaging system, and BFL denotes a distance on an optical axis from an image side surface of the eighth lens to an imaging plane.

[0021] D1 / f<0.1 can be satisfied, where D1 denotes a distance on an optical axis between an image side surface of the first lens and an object side surface of the second lens, and f denotes a total focal length of the optical imaging system.

[0022] FOVx(IMG HT / f)>65° can be satisfied, where f denotes a total focal length of the optical imaging system, and FOV denotes a field of view of the optical imaging system.

[0023] The fifth lens can have at least one inflection point on an image side thereof, and 2<|Y52 / Z52|<50 can be satisfied, where Y52 denotes a perpendicular height between a first inflection point of the image side of the fifth lens and an optical axis, and Z52 denotes a SAG value obtained at the first inflection point of the image side of the fifth lens.

[0024] The sixth lens can have at least one inflection point on an image side thereof, and 3<|Y62 / Z62|<50 can be satisfied, where Y62 denotes a perpendicular height between a first inflection point of the image side of the sixth lens and an optical axis, and Z62 denotes a SAG value obtained at the first inflection point of the image side of the sixth lens.

[0025] The seventh lens can have at least one inflection point on an image side thereof, and 5<|Y72 / Z72|<120 can be satisfied, where Y72 denotes a perpendicular height between a first inflection point of the image side of the seventh lens and an optical axis, and Z72 denotes a SAG value obtained at the first inflection point of the image side of the seventh lens.

[0026] The eighth lens can have at least one inflection point on an image side thereof, and 2<|Y82 / Z82|<30 can be satisfied, where Y82 denotes a perpendicular height between a first inflection point of the image side of the eighth lens and an optical axis, and Z82 denotes a SAG value obtained at the first inflection point of the image side of the eighth lens.

[0027] Other features and aspects will become apparent from the following claims, drawings and detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0028] The above and other aspects, features, and advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0029] Figure 1 is a view showing an optical imaging system according to a first example.

[0030] Figure 2 is a view showing Figure 1 of an exemplary optical imaging system shown.

[0031] Figure 3 is a view showing an optical imaging system according to a second example.

[0032] Figure 4 is a view showing Figure 3 of an exemplary optical imaging system shown.

[0033] Figure 5 is a view showing an optical imaging system according to a third example.

[0034] Figure 6 is a view showing Figure 5 of an exemplary optical imaging system shown.

[0035] Figure 7 is a view showing an optical imaging system according to a fourth example.

[0036] Figure 8 is a view showing Figure 7 of an exemplary optical imaging system shown.

[0037] Figure 9 is a view showing an optical imaging system according to a fifth example.

[0038] Figure 10 is a view showing Figure 9 of an exemplary optical imaging system shown.

[0039] Figure 11 is a view showing an optical imaging system according to a sixth example.

[0040] Figure 12 is a view showing Figure 11 of an exemplary optical imaging system shown.

[0041] Figure 13 is a view showing an optical imaging system according to a seventh example.

[0042] Figure 14 is a view showing Figure 13Views of aberration characteristics of the exemplary optical imaging system shown.

[0043] Figure 15 is a view showing an optical imaging system according to the eighth example.

[0044] Figure 16 is a view showing Figure 15 Views of aberration characteristics of the exemplary optical imaging system shown.

[0045] Figure 17 is a view showing an optical imaging system according to the ninth example.

[0046] Figure 18 is a view showing Figure 17 Views of aberration characteristics of the exemplary optical imaging system shown.

[0047] Figure 19 is a view showing an optical imaging system according to the tenth example.

[0048] Figure 20 is a view showing Figure 19 Views of aberration characteristics of the exemplary optical imaging system shown.

[0049] Figure 21 is a view showing Y82 and Z82 according to one or more embodiments.

[0050] Throughout the drawings and detailed description, identical reference labels can refer to identical elements. The drawings can not be to scale and the relative dimensions, proportions, and depiction of elements in the drawings can be exaggerated for purpose of clarity, illustration and convenience. DETAILED DESCRIPTION

[0051] The following detailed description is provided to help the reader understand the methods, devices, and / or systems described herein. However, various changes, modifications, and equivalents can become apparent to the reader familiar with the disclosure of this application. For example, the order of the operations described herein can be merely exemplary and not limiting, except as can be necessitated by the specific sequence of operations, and can be changed as will be apparent to one of ordinary skill in the art, upon understanding the present disclosure. Furthermore, the description can omit the description of features known after understanding the disclosure of the present application, for the sake of clarity and conciseness, but it should be noted that the omission of the features and their description is not intended to recognize them as common general knowledge.

[0052] The features described herein can be implemented in different forms and should not be construed as limited to the examples described herein. Rather, these examples are provided as illustrative of a number of possible ways to implement the methods, devices, and / or systems described herein after a thorough understanding of the disclosure provided herein.

[0053] Although terminology can be used in this document, such as "first," "second," and "third," to describe various components, parts, regions, layers, or sections, these components, parts, regions, layers, or sections should not be limited to the terminology. Rather, the terminology is used only for the purpose of distinguishing one component, part, region, layer, or section from another component, part, region, layer, or section. Therefore, the first component, first part, first region, first layer, or first section mentioned in the examples can also be called the second component, second part, second region, second layer, or second section without departing from the teachings of the examples described herein.

[0054] The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. As used herein, the terms "comprises," "comprising," "includes," "including," and "has," "having," their variants, and / or the like, indicate the presence of the stated features, numbers, operations, elements, components, and / or a combination thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, elements, components, and / or a combination thereof.

[0055] In addition, terms such as first, second, A, B, (a), (b), etc. can be used herein to describe various components. Each of these terms does not limit the respective component to the specific, ordinal number or order, but rather the terms are used to distinguish a respective component from another. Thus, a first component belonging to one example is a second component in another example, and vice versa.

[0056] Throughout the specification, when an element such as a layer, region, or substrate is referred to as being "on", "connected to", or "coupled to" another element, it can be directly on, directly connected to, or directly coupled to the other element, or one or more other elements can be interposed therebetween. Conversely, when an element is referred to as being "directly on", "directly connected to", or "directly coupled to" another element, there are no other elements interposed therebetween. Similarly, expressions such as "between" and "directly between", and "adjacent" and "directly adjacent", can also be interpreted in the manner as set forth above.

[0057] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs in view of the disclosure provided herein. For example, terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the disclosure provided herein, and are not to be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0058] Also, in the description of the exemplary embodiments, detailed descriptions of the structure or function which are considered to be known after understanding the disclosure of the present application by those skilled in the art will be omitted so as not to obscure the interpretation of the exemplary embodiments.

[0059] Hereinafter, examples will be described in detail with reference to the accompanying drawings, and the same reference numerals in the drawings always refer to the same elements.

[0060] In the drawings, the thickness, size, and shape of the lens are slightly exaggerated for convenience of explanation. Specifically, the shape of the spherical surface or aspherical surface shown in the drawings is merely illustrative. That is, the shape of the spherical surface or aspherical surface is not limited to the shape shown in the drawings.

[0061] One aspect of one or more examples can provide an optical imaging system that can achieve high resolution and has a small total length.

[0062] The first lens can denote a lens disposed closest to the object side, and the eighth lens can denote a lens disposed closest to the imaging plane (or image sensor).

[0063] In addition, the first surface of each lens can denote its surface closest to the object side (or object side surface), and the second surface of each lens can denote its surface closest to the image side (or image side surface). In addition, all numerical values of the radius of curvature, thickness, distance, focal length, etc. of the lens can be denoted by millimeters (mm), and the field of view angle (FOV) can be denoted by degrees (°).

[0064] In addition, in the description of the shape of each lens, it can be denoted that one surface of the lens has a convex shape, one surface of the lens has a concave shape, and one surface of the lens has a flat shape, which means that the paraxial region of the corresponding surface is convex, concave, and flat, respectively. Therefore, although it is described that one surface of the lens is convex, the edge portion of the lens can be concave. Likewise, although it is described that one surface of the lens is concave, the edge portion of the lens can be convex. In addition, although it is described that one surface of the lens is flat, the edge portion of the lens can be convex or concave.

[0065] Meanwhile, the near-axis region can mean a very narrow region near the optical axis.

[0066] The imaging plane can mean a virtual plane in which a focus is formed by the optical imaging system. Alternatively, the imaging plane can mean one surface of the image sensor on which light is received.

[0067] The optical imaging system according to one or more embodiments can include eight lenses.

[0068] In an example, the optical imaging system according to one or more embodiments can include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens sequentially disposed from an object side to an imaging side. The first lens to the eighth lens can be respectively arranged to be spaced apart from each other by a predetermined distance along the optical axis.

[0069] However, the optical imaging system according to one or more embodiments is not limited to including only eight lenses, and if necessary, can further include another component and an additional lens or fewer lenses.

[0070] In an example, the optical imaging system can further include an image sensor that converts an image of an object incident onto the image sensor into an electrical signal.

[0071] In addition, the optical imaging system can further include an infrared filter (hereinafter referred to as a filter) that blocks infrared rays. The filter can be disposed between the eighth lens and the image sensor. In addition, the optical imaging system can further include an aperture that adjusts the amount of light.

[0072] Meanwhile, the fifth lens to the eighth lens can each include one or more inflection points on the image side surface. In an example, the fifth lens to the eighth lens can each include two inflection points on the image side surface.

[0073] The fifth lens to the eighth lens can each have at least one inflection point and a critical point on the image side surface.

[0074] The inflection point can mean a point at which the surface of the lens changes from concave to convex, or a point at which the surface of the lens changes from convex to concave. In addition, the critical point can mean a position on the lens when a tangent line at an arbitrary point on the surface of the lens is perpendicular to the optical axis.

[0075] According to one or more embodiments, some of the plurality of lenses included in the optical imaging system can be formed of glass, and the other lenses can be formed of plastic.

[0076] For example, at least one lens including the first lens can be formed of glass, and the remaining lenses can be formed of plastic.

[0077] In an example, the first lens can be formed of glass having an Abbe number greater than 70.

[0078] In an example, the Abbe number of the first lens can be the largest among the Abbe numbers of the first lens to the eighth lens.

[0079] In an example, the first lens can be formed of glass, and the second lens to the eighth lens can be formed of plastic. Also, the second lens to the eighth lens can each be formed of plastic having different optical characteristics from the optical characteristics of the adjacent lens.

[0080] In an example, the first lens and the second lens can be formed of glass, and the third lens to the eighth lens can be formed of plastic. Also, the third lens to the eighth lens can each be formed of plastic having different optical characteristics from the optical characteristics of the adjacent lens.

[0081] In an example, the first lens to the third lens can each be formed of glass, and the fourth lens to the eighth lens can be formed of plastic. Also, the fourth lens to the eighth lens can each be formed of plastic having different optical characteristics from the optical characteristics of the adjacent lens.

[0082] In an example, the first lens to the fourth lens can each be formed of glass, and the fifth lens to the eighth lens can be formed of plastic. Also, the fifth lens to the eighth lens can each be formed of plastic having different optical characteristics from the optical characteristics of the adjacent lens.

[0083] In an example, at least three lenses among the first lens to the eighth lens can each have a refractive index greater than 1.61. In an example, the refractive indices of the second lens, the fourth lens, and the sixth lens can each be greater than 1.61. Alternatively, the refractive indices of the second lens, the fourth lens, and the seventh lens can each be greater than 1.61.

[0084] In an example, at least two lenses among the first lens to the eighth lens can each have a refractive index greater than 1.65 and a negative refractive power.

[0085] In an example, the second lens and the fourth lens can each be formed of glass or plastic having a refractive index greater than 1.65 and an Abbe number less than 22.

[0086] At least one of the first lens to the eighth lens can have an aspheric surface. Also, each of the first lens to the eighth lens can have at least one aspheric surface.

[0087] That is, at least one of the first surface and the second surface of all the first lens to the eighth lens can be aspheric. In one or more examples, the aspheric surface of the first lens to the eighth lens can be represented by Equation 1 below.

[0088] Equation 1:

[0089]

[0090] In Equation 1, "c" can denote a curvature of a lens (an inverse of a radius of curvature), "K" can denote a conic constant, and "Y" can denote a distance from an arbitrary point on an aspherical surface of the lens to an optical axis. Further, each of constants "A" to "P" can denote a coefficient of the aspherical surface. Further, "Z (SAG)" can denote a distance from an arbitrary point on the aspherical surface of the lens to a vertex of the aspherical surface in a direction of the optical axis.

[0091] According to one or more embodiments, the optical imaging system can satisfy the following conditional expressions:

[0092] [Conditional Expression 1] 0 < f1 / f < 1.4

[0093] [Conditional Expression 2] 40 < v1-v2 < 70

[0094] [Conditional Expression 3] 30 < v1-v4 < 70

[0095] [Conditional Expression 4] 20 < v1-(v6+v7) / 2 < 50

[0096] [Conditional Expression 5] -10 < f2 / f < -1

[0097] [Conditional Expression 6] 0 < |f3 / f| / 10 < 30

[0098] [Conditional Expression 7] 0.5 < |f6 / f| < 10

[0099] [Conditional Expression 8] -3 < f8 / f < 0

[0100] [Conditional Expression 9] TTL / f < 1.4

[0101] [Conditional Expression 10] BFL / f < 0.3

[0102] [Conditional Expression 11] D1 / f < 0.1

[0103] [Conditional Expression 12] TTL / (2×IMG HT) < 0.6

[0104] [Conditional Expression 13] FOV×(IMG HT / f) > 65°

[0105] [Conditional Expression 14] -0.2 < SAG52 / TTL < 0

[0106] [Condition Expression 15] -0.2 < SAG62 / TTL < 0

[0107] [Condition Expression 16] -0.3 < SAG72 / TTL < 0

[0108] [Condition Expression 17] -0.3 < SAG82 / TTL < 0

[0109] [Condition Expression 18] 2 < |Y52 / Z52| < 50

[0110] [Condition Expression 19] 3 < |Y62 / Z62| < 50

[0111] [Condition Expression 20] 5 < |Y72 / Z72| < 120

[0112] [Condition Expression 21] 2 < |Y82 / Z82| < 30

[0113] In the condition expressions, f can denote a total focal length of the optical imaging system, f1 can denote a focal length of the first lens, f2 can denote a focal length of the second lens, f3 can denote a focal length of the third lens, f6 can denote a focal length of the sixth lens, and f8 can denote a focal length of the eighth lens.

[0114] v1 can denote an Abbe number of the first lens, v2 can denote an Abbe number of the second lens, v4 can denote an Abbe number of the fourth lens, v6 can denote an Abbe number of the sixth lens, and v7 can denote an Abbe number of the seventh lens.

[0115] TTL can denote a distance from a subject side surface of the first lens to an imaging surface in an optical axis direction, and BFL can denote a distance from an image side surface of the eighth lens to the imaging surface in the optical axis direction.

[0116] D1 can denote a distance between an image side surface of the first lens and a subject side surface of the second lens in the optical axis direction, IMG HT can denote half of a diagonal length of the imaging surface, and FOV can denote a field of view of the optical imaging system.

[0117] SAG52 can denote a SAG value obtained at an end of an effective diameter of an image side surface of the fifth lens, SAG62 can denote a SAG value obtained at an end of an effective diameter of an image side surface of the sixth lens, SAG72 can denote a SAG value obtained at an end of an effective diameter of an image side surface of the seventh lens, and SAG82 can denote a SAG value obtained at an end of an effective diameter of an image side surface of the eighth lens.

[0118] The SAG value can have a negative value when an end of an effective diameter of a corresponding surface of a lens is closer to a subject side than a vertex of the corresponding surface of the lens in the optical axis direction.

[0119] The SAG value can have a positive value when an end portion of the effective diameter of the corresponding surface of the lens is closer to the image side than an apex of the corresponding surface of the lens in the optical axis direction.

[0120] Y52 can represent a vertical height between the first inflection point of the image side surface of the fifth lens and the optical axis, Y62 can represent a vertical height between the first inflection point of the image side surface of the sixth lens and the optical axis, Y72 can represent a vertical height between the first inflection point of the image side surface of the seventh lens and the optical axis, and Y82 can represent a vertical height between the first inflection point of the image side surface of the eighth lens and the optical axis.

[0121] Z52 can represent a SAG value obtained at the first inflection point of the image side surface of the fifth lens, Z62 can represent a SAG value obtained at the first inflection point of the image side surface of the sixth lens, Z72 can represent a SAG value obtained at the first inflection point of the image side surface of the seventh lens, and Z82 can represent a SAG value obtained at the first inflection point of the image side surface of the eighth lens.

[0122] The specification describes a first lens to an eighth lens included in an optical imaging system according to one or more embodiments.

[0123] The first lens can have a positive refractive power. In addition, the first lens can have a meniscus shape convex on its object side. Specifically, the first lens can have a convex first surface and a concave second surface.

[0124] At least one of the first surface and the second surface of the first lens can be aspherical. In an example, both surfaces of the first lens can be aspherical.

[0125] The second lens can have a negative refractive power. In addition, the second lens can have a meniscus shape convex on its object side. Specifically, the second lens can have a convex first surface and a concave second surface.

[0126] At least one of the first surface and the second surface of the second lens can be aspherical. For example, both surfaces of the second lens can be aspherical.

[0127] The third lens can have a positive refractive power or a negative refractive power. In addition, the third lens can have a meniscus shape convex on its object side. Specifically, the third lens can have a convex first surface and a concave second surface.

[0128] At least one of the first surface and the second surface of the third lens can be aspherical. For example, both surfaces of the third lens can be aspherical.

[0129] The fourth lens can have a positive refractive power or a negative refractive power. Also, both surfaces of the fourth lens can be concave. Specifically, the fourth lens can have a concave first surface and a concave second surface.

[0130] Alternatively, the fourth lens can have a meniscus shape convex on its object side. Specifically, the fourth lens can have a convex first surface and a concave second surface.

[0131] Alternatively, the fourth lens can have a meniscus shape convex on its image side. Specifically, the fourth lens can have a concave first surface and a convex second surface.

[0132] At least one of the first surface and the second surface of the fourth lens can be aspherical. In an example, both surfaces of the fourth lens can be aspherical.

[0133] The fifth lens can have a positive refractive power or a negative refractive power. Also, the fifth lens can have a meniscus shape convex on its image side. Specifically, the fifth lens can have a concave first surface and a convex second surface.

[0134] Alternatively, the fifth lens can have a meniscus shape convex on its object side. Specifically, the fifth lens can have a first surface convex in a paraxial region and a second surface concave in the paraxial region.

[0135] At least one of the first surface and the second surface of the fifth lens can be aspherical. In an example, both surfaces of the fifth lens can be aspherical.

[0136] At least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens. In an example, the fifth lens can have a first surface concave in a paraxial region and convex in a region other than the paraxial region. The fifth lens can have a second surface convex in the paraxial region and can be concave in a region other than the paraxial region.

[0137] The sixth lens can have a positive refractive power or a negative refractive power. Also, the sixth lens can have a meniscus shape convex on its object side. Specifically, the sixth lens can have a first surface convex in a paraxial region and a second surface concave in the paraxial region.

[0138] Alternatively, both surfaces of the sixth lens can be convex. Specifically, the sixth lens can have a first surface and a second surface convex in a paraxial region.

[0139] At least one of the first surface and the second surface of the sixth lens can be aspherical. In an example, both surfaces of the sixth lens can be aspherical.

[0140] At least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens. In an example, the sixth lens can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. The sixth lens can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0141] The seventh lens can have a positive refractive power or a negative refractive power. Also, both surfaces of the seventh lens can be convex. Specifically, the first and second surfaces of the seventh lens can be convex.

[0142] Alternatively, the seventh lens can have a meniscus shape with its image-side surface convex. Specifically, the seventh lens can have a first surface that is concave in the paraxial region and a second surface that is convex in the paraxial region.

[0143] At least one of the first and second surfaces of the seventh lens can be aspherical. In an example, both surfaces of the seventh lens can be aspherical.

[0144] Also, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens. In an example, the seventh lens can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. The second surface of the seventh lens can be convex in the paraxial region and concave in a region other than the paraxial region.

[0145] The eighth lens can have a negative refractive power. Also, the eighth lens can have a meniscus shape with its object-side surface convex. Specifically, the eighth lens can have a first surface that is convex in the paraxial region and a second surface that is concave in the paraxial region.

[0146] At least one of the first and second surfaces of the eighth lens can be aspherical. In an example, both surfaces of the eighth lens can be aspherical.

[0147] Also, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens. In an example, the eighth lens can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. The eighth lens can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0148] An optical imaging system 100 according to a first example will be described with reference to Figure 1 and Figure 2 An optical imaging system 100 according to a first example will be described with reference to

[0149] The optical imaging system 100 according to the first example can include a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, a seventh lens 170, and an eighth lens 180, and can further include a filter 190 and an image sensor IS including an imaging surface 191.

[0150] The optical imaging system 100 according to the first example can focus an image on the imaging surface 191. The imaging surface 191 can represent a surface on which a focal point is formed by the optical imaging system 100. For example, the imaging surface 191 can represent one surface of the image sensor IS on which light is received.

[0151] Tables 1 and 2 show characteristics (e.g., a radius of curvature, a thickness of a lens or a distance between lenses, a refractive index, an Abbe number, and a focal length) of each lens.

[0152] Table 1

[0153]

[0154]

[0155] Table 2

[0156] f 4.52 Y52 1.4497 IMG HT 5.107 Y62 0.4845 FOV 93.6 Y72 0.7149 SAG52 -0.3815 Y82 0.5766 SAG62 -0.3947 Z52 -0.27508 SAG72 -0.8076 Z62 0.03288 SAG82 -0.9136 Z72 -0.06076 Z82 0.08385

[0157] In the first example, the first lens 110 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0158] The second lens 120 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0159] The third lens 130 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0160] The fourth lens 140 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0161] The fifth lens 150 can have a negative refractive power, while the first surface can be concave in a paraxial region, and the second surface can be convex in the paraxial region.

[0162] In addition, at least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens 150. In an example, the fifth lens 150 can have a first surface that is concave in a paraxial region and convex in a region other than the paraxial region. Further, the fifth lens 150 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0163] The sixth lens 160 can have a negative refractive power, while the first surface of the sixth lens 160 can be concave in the paraxial region.

[0164] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 160. In an example, the first surface of the sixth lens 160 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 160 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0165] The seventh lens 170 can have a positive refractive power, and the first and second surfaces can be convex in the paraxial region.

[0166] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 170. In an example, the seventh lens 170 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the seventh lens 170 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0167] The eighth lens 180 can have a negative refractive power, while the first surface of the eighth lens 180 can be concave in the paraxial region.

[0168] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 180. In an example, the eighth lens 180 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 180 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0169] The first lens 110 can be formed of glass, and the second lens 120 to the eighth lens 180 can be formed of plastic. Further, the second lens 120 to the eighth lens 180 can each be formed of plastic having optical characteristics different from those of an adjacent lens.

[0170] In an example, the first lens 110 can be formed of glass having a high dispersion value, and the second lens 120 and the fourth lens 140 can each be formed of plastic having a high refractive index and a low dispersion value.

[0171] In an example, each surface of the first lens 110 to the eighth lens 180 can have an aspheric coefficient as shown in Table 3. In an example, the object side surface and the image side surface of the first lens 110 to the eighth lens 180 can each be an aspheric surface.

[0172] Table 3

[0173] S1 S2 S3 S4 S5 S6 S7 S8 K -2.938 -59.628 27.579 11.874 3.652 99.000 -99.000 -99.000 A 2.312E-02 -3.696E-02 -1.676E-02 2.926E-02 -9.997E-02 -6.646E-02 -6.995E-02 -3.075E-02 B 3.241E-02 3.812E-01 -3.931E-03 -9.044E-01 1.822E+00 8.845E-01 -7.793E-02 -1.900E-01 C -1.979E-01 -2.758E+00 4.464E-02 1.011E+01 -2.242E+01 -9.357E+00 2.582E-01 1.168E+00 D 5.647E-01 1.196E+01 2.963E-01 -7.247E+01 1.745E+02 6.422E+01 -7.053E-01 -6.740E+00 E -9.783E-01 -3.409E+01 -2.304E+00 3.553E+02 -9.128E+02 -3.005E+02 -1.212E+00 2.609E+01 F 9.295E-01 6.692E+01 7.819E+00 -1.227E+03 3.338E+03 9.895E+02 1.753E+01 -6.857E+01 G -1.813E-01 -9.296E+01 -1.755E+01 3.035E+03 -8.730E+03 -2.339E+03 -6.929E+01 1.262E+02 H -7.167E-01 9.268E+01 2.888E+01 -5.421E+03 1.650E+04 4.013E+03 1.578E+02 -1.659E+02 J 1.037E+00 -6.650E+01 -3.534E+01 6.989E+03 -2.255E+04 -5.001E+03 -2.336E+02 1.567E+02 L -7.470E-01 3.402E+01 3.131E+01 -6.430E+03 2.205E+04 4.478E+03 2.324E+02 -1.056E+02 M 3.273E-01 -1.210E+01 -1.926E+01 4.112E+03 -1.501E+04 -2.807E+03 -1.547E+02 4.965E+01 N -8.820E-02 2.839E+00 7.723E+00 -1.735E+03 6.757E+03 1.168E+03 6.622E+01 -1.546E+01 O 1.349E-02 -3.953E-01 -1.808E+00 4.337E+02 -1.806E+03 -2.902E+02 -1.648E+01 2.871E+00 P -8.990E-04 2.472E-02 1.868E-01 -4.864E+01 2.169E+02 3.251E+01 1.814E+00 -2.405E-01 S9 S10 S11 S12 S13 S14 S15 S16 K 5.790 5.479 -9.239 -1.981 5.290 -11.901 2.810 -6.783 A 6.299E-02 3.891E-02 -9.045E-02 -1.412E-01 5.189E-02 7.430E-02 -2.295E-01 -1.147E-01 B 1.857E-02 1.167E-01 8.254E-02 3.577E-02 -1.431E-01 -4.380E-02 1.348E-01 6.800E-02 C -9.672E-01 -1.344E+00 -2.513E-01 -7.491E-02 6.152E-02 -4.218E-02 -5.658E-02 -2.722E-02 D 3.432E+00 4.157E+00 5.016E-01 3.981E-01 1.525E-01 1.318E-01 1.495E-02 6.452E-03 E -6.980E+00 -7.726E+00 -5.032E-01 -8.279E-01 -3.035E-01 -1.508E-01 -1.011E-03 -4.862E-04 F 9.715E+00 9.703E+00 -3.877E-02 9.454E-01 2.764E-01 1.033E-01 -7.344E-04 -2.177E-04 G -9.780E+00 -8.441E+00 7.425E-01 -6.789E-01 -1.563E-01 -4.717E-02 2.922E-04 8.827E-05 H 7.399E+00 5.094E+00 -9.686E-01 3.263E-01 5.960E-02 1.496E-02 -5.659E-05 -1.682E-05 J -4.387E+00 -2.105E+00 6.825E-01 -1.080E-01 -1.577E-02 -3.336E-03 6.890E-06 2.008E-06 L 2.090E+00 5.731E-01 -3.032E-01 2.478E-02 2.908E-03 5.213E-04 -5.598E-07 -1.595E-07 M -7.785E-01 -9.378E-02 8.751E-02 -3.877E-03 -3.670E-04 -5.579E-05 3.047E-08 8.436E-09 N 2.071E-01 6.830E-03 -1.597E-02 3.955E-04 3.025E-05 3.892E-06 -1.071E-09 -2.862E-10 O -3.374E-02 2.113E-04 1.679E-03 -2.373E-05 -1.468E-06 -1.593E-07 2.203E-11 5.638E-12 P 2.467E-03 -4.871E-05 -7.754E-05 6.361E-07 3.179E-08 2.897E-09 -2.017E-13 -4.905E-14

[0174] Further, the exemplary optical imaging system 100 configured as described above can have Figure 2 aberration characteristics as shown.

[0175] Referring to Figure 3 and Figure 4 An optical imaging system 200 according to a second example is described.

[0176] The optical imaging system 200 according to the second example can include a first lens 210, a second lens 220, a third lens 230, a fourth lens 240, a fifth lens 250, a sixth lens 260, a seventh lens 270, and an eighth lens 280, and can further include a filter 290 and an image sensor IS including an imaging surface 291.

[0177] The optical imaging system 200 according to the second example can focus an image on the imaging surface 291. The imaging surface 291 can represent a surface on which a focal point is formed by the optical imaging system 200. In an example, the imaging surface 291 can represent one surface of the image sensor IS on which light is received.

[0178] Table 4 and Table 5 show the characteristics (e.g., a radius of curvature, a thickness of a lens or a distance between lenses, a refractive index, an Abbe number, and a focal length) of each lens.

[0179] Table 4

[0180] Surface No. Item Radius of Curvature Thickness or Distance Refractive Index Abbe Number Focal Length S1 First Lens 2.012 0.621 1.497 81.6 5.78 S2 First Lens 5.992 0.100 S3 Second Lens 7.872 0.220 1.680 18.2 -18.74 S4 Second Lens 4.835 0.100 S5 Third Lens 5.640 0.322 1.535 55.7 13.18 S6 Third Lens 27.224 0.366 S7 Fourth Lens 278.650 0.221 1.650 21.5 -1778.84 S8 Fourth Lens 224.959 0.198 S9 Fifth Lens -6.097 0.241 1.535 55.7 -82.38 S10 Fifth Lens -7.169 0.156 S11 Sixth Lens 3.682 0.281 1.614 25.9 -16.87 S12 Sixth Lens 2.644 0.172 S13 Seventh Lens 6.455 0.449 1.544 56.0 3.95 S14 Seventh Lens -3.163 0.744 S15 Eighth Lens 21.100 0.360 1.535 55.7 -3.15 S16 Eighth Lens 1.558 0.200 S17 Filter Infinity 0.110 1.517 64.2 S18 Infinity 0.639 S19 Imaging Surface Infinity

[0181] Table 5

[0182]

[0183]

[0184] In the second example, the first lens 210 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0185] The second lens 220 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0186] The third lens 230 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0187] The fourth lens 240 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0188] The fifth lens 250 can have a negative refractive power, while the first surface can be concave in the paraxial region, and the second surface can be convex in the paraxial region.

[0189] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens 250. In an example, the fifth lens 250 can have a first surface that is concave in the paraxial region and convex in a region other than the paraxial region. Further, the fifth lens 250 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0190] The sixth lens 260 can have a negative refractive power, while the first surface of the sixth lens 260 can be concave in the paraxial region.

[0191] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the sixth lens 260. In an example, the first surface of the sixth lens 260 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 260 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0192] The seventh lens 270 can have a positive refractive power, and the first surface and the second surface of the seventh lens 270 can be convex in the paraxial region.

[0193] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the seventh lens 270. In an example, the seventh lens 270 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the seventh lens 270 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0194] The eighth lens 280 can have a negative refractive power, while the first surface of the eighth lens 280 can be concave in the paraxial region.

[0195] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the eighth lens 280. In an example, the eighth lens 280 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 280 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0196] The first lens 210 may be made of glass, and the second lens 220 to the eighth lens 280 may be made of plastic. Furthermore, each of the second lens 220 to the eighth lens 280 may be made of a plastic having optical properties different from those of the adjacent lenses.

[0197] In the example, the first lens 210 may be formed of glass with a high dispersion value, and the second lens 220 and the fourth lens 240 may each be formed of plastic with a high refractive index and a low dispersion value.

[0198] In the example, each surface of the first lens 210 to the eighth lens 280 may have an aspheric coefficient as shown in Table 6. In the example, both the object-side surface and the image-side surface of the first lens 210 to the eighth lens 280 may be aspherical surfaces.

[0199] Table 6

[0200]

[0201]

[0202] Furthermore, the optical imaging system 200 configured as described above may have Figure 4 The aberration characteristics shown.

[0203] refer to Figure 5 and Figure 6 The optical imaging system 300 is described according to the third example.

[0204] The optical imaging system 300 according to the third example may include a first lens 310, a second lens 320, a third lens 330, a fourth lens 340, a fifth lens 350, a sixth lens 360, a seventh lens 370, and an eighth lens 380, and may also include a filter 390 and an image sensor IS including an imaging surface 391.

[0205] According to the third example, the optical imaging system 300 can focus an image onto the imaging surface 391. The imaging surface 391 can represent the surface on which the optical imaging system 300 forms a focal point. In the example, the imaging surface 391 can represent a surface of the image sensor IS on which light is received.

[0206] Tables 7 and 8 show the characteristics of each lens (e.g., radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length).

[0207] Table 7

[0208]

[0209]

[0210] Table 8

[0211] f 4.56 Y52 1.4602 IMG HT 5.107 Y62 0.5796 FOV 93 Y72 0.5338 SAG52 -0.3707 Y82 0.5556 SAG62 -0.5004 Z52 -0.27167 SAG72 -0.6747 Z62 0.04642 SAG82 -1.0326 Z72 -0.03621 Z82 0.07649

[0212] In a third example, the first lens 310 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0213] The second lens 320 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0214] The third lens 330 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0215] The fourth lens 340 can have a positive refractive power, and have a concave first surface and a convex second surface.

[0216] The fifth lens 350 can have a negative refractive power, while the first surface of the fifth lens 350 can be concave in the paraxial region, and the second surface of the fifth lens 350 can be convex in the paraxial region.

[0217] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens 350. In an example, the fifth lens 350 can have a first surface that is concave in the paraxial region and convex in a region other than the paraxial region. Further, the fifth lens 350 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0218] The sixth lens 360 can have a negative refractive power, while the first surface of the sixth lens 360 can be concave in the paraxial region.

[0219] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the sixth lens 360. In an example, the first surface of the sixth lens 360 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 360 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0220] The seventh lens 370 can have a positive refractive power, and the first surface and the second surface of the seventh lens 370 can be convex in the paraxial region.

[0221] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 370. In an example, the seventh lens 370 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the seventh lens 370 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0222] The eighth lens 380 can have a negative refractive power, while the first surface of the eighth lens 380 can be concave in the paraxial region.

[0223] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 380. In an example, the eighth lens 380 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 380 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0224] The first lens 310 can be formed of glass, and the second lens 320 through the eighth lens 380 can be formed of plastic. Further, the second lens 320 through the eighth lens 380 can each be formed of plastic having optical characteristics different from those of the adjacent lens.

[0225] In an example, the first lens 310 can be formed of glass having a high dispersion value, and the second lens 320 and the fourth lens 340 can each be formed of plastic having a high refractive index and a low dispersion value.

[0226] In an example, each surface of the first lens 310 through the eighth lens 380 can have aspherical coefficients as shown in Table 9. In an example, the object side surface and the image side surface of the first lens 310 through the eighth lens 380 can each be an aspherical surface.

[0227] Table 9

[0228]

[0229]

[0230] Further, the optical imaging system 300 configured as described above can have Figure 6 aberration characteristics as shown.

[0231] Referring to Figure 7 and 8 An optical imaging system 400 according to a fourth example is described.

[0232] The optical imaging system 400 according to the fourth example can include the first lens 410, the second lens 420, the third lens 430, the fourth lens 440, the fifth lens 450, the sixth lens 460, the seventh lens 470, and the eighth lens 480, and can further include the optical filter 490 and the image sensor IS including the imaging surface 491.

[0233] The optical imaging system 400 according to the fourth example can focus an image on the imaging surface 491. The imaging surface 491 can represent a surface on which a focal point is formed by the optical imaging system 400. In an example, the imaging surface 491 can represent one surface of the image sensor IS on which light is received.

[0234] Tables 10 and 11 show the characteristics (e.g., the radius of curvature, the thickness of the lens or the distance between the lenses, the refractive index, the Abbe number, and the focal length) of each lens.

[0235] Table 10

[0236]

[0237]

[0238] Table 11

[0239] f 4.53 Y52 0.3182 IMG HT 5.107 Y62 0.4634 FOV 93.5 Y72 0.469 SAG52 -0.5451 Y82 0.5992 SAG62 -0.7441 Z52 0.00989 SAG72 -0.6513 Z62 -0.02093 SAG82 -0.9297 Z72 -0.01557 Z82 0.08053

[0240] In the fourth example, the first lens 410 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0241] The second lens 420 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0242] The third lens 430 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0243] The fourth lens 440 can have a negative refractive power, and have concave first and second surfaces.

[0244] The fifth lens 450 can have a negative refractive power, while the first surface of the fifth lens 450 can be concave in the paraxial region.

[0245] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 450. In an example, the fifth lens 450 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the fifth lens 450 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0246] The sixth lens 460 can have a positive refractive power, and the first and second surfaces can be convex in a paraxial region.

[0247] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 460. In an example, the first surface of the sixth lens 460 can be convex in a paraxial region, and concave in a region other than the paraxial region. Further, the sixth lens 460 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0248] The seventh lens 470 can have a positive refractive power, while the first surface of the seventh lens 470 can be concave in a paraxial region, and the second surface of the seventh lens 470 can be convex in the paraxial region.

[0249] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 470. In an example, the seventh lens 470 can have a first surface that is concave in a paraxial region and convex in a region other than the paraxial region. Further, the seventh lens 470 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0250] The eighth lens 480 can have a negative refractive power, while the first surface of the eighth lens 480 can be concave in a paraxial region.

[0251] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 480. In an example, the eighth lens 480 can have a first surface that is convex in a paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 480 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0252] The first lens 410 can be formed of glass, and the second lens 420 through the eighth lens 480 can be formed of plastic. Further, the second lens 420 through the eighth lens 480 can each be formed of plastic having optical characteristics different from those of an adjacent lens.

[0253] In an example, the first lens 410 can be formed of glass having a high dispersion value, and the second lens 420 and the fourth lens 440 can each be formed of plastic having a high refractive index and a low dispersion value.

[0254] In one example, each surface of the first lens 410 through the eighth lens 480 can have an aspheric coefficient as shown in Table 12. In an example, the object side surface and the image side surface of the first lens 410 through the eighth lens 480 can each be an aspheric surface.

[0255] Table 12

[0256]

[0257]

[0258] Further, the optical imaging system 400 configured as described above can have Figure 8 aberration characteristics as illustrated.

[0259] Referring to Figure 9 and Figure 10 An optical imaging system 500 according to a fifth example is described.

[0260] The optical imaging system 500 according to the fifth example can include a first lens 510, a second lens 520, a third lens 530, a fourth lens 540, a fifth lens 550, a sixth lens 560, a seventh lens 570, and an eighth lens 580, and can further include a filter 590 and an image sensor IS including an imaging surface 591.

[0261] The optical imaging system 500 according to the fifth example can form an image on the imaging surface 591. The imaging surface 591 can represent a surface on which a focal point is formed by the optical imaging system 500. In an example, the imaging surface 591 can represent one surface of the image sensor IS on which light is received.

[0262] Table 13 and Table 14 show the characteristics (e.g., the radius of curvature, the thickness of the lens or the distance between the lenses, the refractive index, the Abbe number, and the focal length) of each lens.

[0263] Table 13

[0264] Surface No. Item Radius of Curvature Thickness or Distance Refractive Index Abbe Number Focal Length S1 First Lens 2.017 0.625 1.497 81.6 5.77 S2 First Lens 6.068 0.100 S3 Second Lens 7.997 0.220 1.680 18.2 -18.29 S4 Second Lens 4.838 0.100 S5 Third Lens 5.776 0.316 1.535 55.7 12.98 S6 Third Lens 33.039 0.376 S7 Fourth Lens -166.972 0.222 1.650 21.5 -2472.23 S8 Fourth Lens -186.188 0.206 S9 Fifth Lens -7.100 0.257 1.535 55.7 4524.63 S10 Fifth Lens -7.169 0.161 S11 Sixth Lens 3.534 0.290 1.614 25.9 -17.11 S12 Sixth Lens 2.568 0.188 S13 Seventh Lens 6.442 0.430 1.544 56.0 4.21 S14 Seventh Lens -3.499 0.741 S15 Eighth Lens 21.814 0.360 1.535 55.7 -3.16 S16 Eighth Lens 1.568 0.200 S17 Filter Infinity 0.110 1.517 64.2 S18 Infinity 0.597 S19 Imaging Surface Infinity

[0265] Table 14

[0266] f 4.5 Y52 1.4833 IMG HT 5.107 Y62 0.593 FOV 93.7 Y72 0.5601 SAG52 -0.3273 Y82 0.5818 SAG62 -0.3562 Z52 -0.2529 SAG72 -0.6443 Z62 0.05307 SAG82 -0.9947 Z72 -0.03537 Z82 0.08219

[0267] In the fifth example, the first lens 510 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0268] The second lens 520 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0269] The third lens 530 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0270] The fourth lens 540 can have a negative refractive power, and a concave first surface and a convex second surface.

[0271] The fifth lens 550 can have a positive refractive power, while the first surface of the fifth lens 550 can be concave in the paraxial region, and the second surface of the fifth lens 550 can be convex in the paraxial region.

[0272] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens 550. For example, the first surface of the fifth lens 550 can be concave in the paraxial region and convex in a region other than the paraxial region. Further, the second surface of the fifth lens 550 can be convex in the paraxial region and can be concave in a region other than the paraxial region.

[0273] The sixth lens 560 can have a negative refractive power, while the first surface of the sixth lens 560 can be concave in the paraxial region.

[0274] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the sixth lens 560. For example, the first surface of the sixth lens 560 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the second surface of the sixth lens 560 can be concave in the paraxial region and convex in a region other than the paraxial region.

[0275] The seventh lens 570 can have a positive refractive power, and the first surface and the second surface of the seventh lens 570 can be convex in the paraxial region.

[0276] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the seventh lens 570. For example, the first surface of the seventh lens 570 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the second surface of the seventh lens 570 can be convex in the paraxial region and can be concave in a region other than the paraxial region.

[0277] The eighth lens 580 can have a negative refractive power, while the first surface of the eighth lens 580 can be concave in the paraxial region.

[0278] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the eighth lens 580. For example, the first surface of the eighth lens 580 can be convex in the paraxial region and concave in a region other than the paraxial region. The second surface of the eighth lens 580 can be concave in the paraxial region and convex in a region other than the paraxial region.

[0279] The first lens 510 can be formed of glass, and the second lens 520 to the eighth lens 580 can be formed of plastic. Also, the second lens 520 to the eighth lens 580 can each be formed of plastic having optical characteristics different from those of an adjacent lens.

[0280] For example, the first lens 510 can be formed of glass having a high dispersion value, and the second lens 520 and the fourth lens 540 can each be formed of plastic having a high refractive index and a low dispersion value.

[0281] Meanwhile, each surface of the first lens 510 to the eighth lens 580 can have an aspheric coefficient as shown in Table 15. For example, the object side surface and the image side surface of the first lens 510 to the eighth lens 580 can each be an aspheric surface.

[0282] Table 15

[0283]

[0284]

[0285] Also, the optical imaging system 500 configured as described above can have Figure 10 aberration characteristics as shown in Table 18.

[0286] Referring to Figure 11 andAn optical imaging system 600 according to a sixth example is described. Figure 12 The optical imaging system 600 according to the sixth example can include a first lens 610, a second lens 620, a third lens 630, a fourth lens 640, a fifth lens 650, a sixth lens 660, a seventh lens 670, and an eighth lens 680, and can further include a filter 690 and an image sensor IS including an imaging surface 691.

[0287] The optical imaging system 600 according to the sixth example can form an image on the imaging surface 691. The imaging surface 691 can denote a surface on which the optical imaging system 600 forms a focal point. For example, the imaging surface 691 can denote one surface of the image sensor IS on which light is received.

[0288] Tables 16 and 17 show characteristics (e.g., a radius of curvature, a thickness of a lens or a distance between lenses, a refractive index, an Abbe number, and a focal length) of each lens.

[0289] Table 16

[0290]

[0291]

[0292]

[0293] Table 17

[0294] f 4.48 Y52 1.5127 IMG HT 5.107 Y62 0.6082 FOV 94.1 Y72 0.5423 SAG52 -0.3339 Y82 0.5803 SAG62 -0.3456 Z52 -0.26646 SAG72 -0.6294 Z62 0.05639 SAG82 -0.9931 Z72 -0.0334 Z82 0.08288

[0295] In a sixth example, the first lens 610 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0296] The second lens 620 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0297] The third lens 630 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0298] The fourth lens 640 can have a positive refractive power, and have a concave first surface and a convex second surface.

[0299] The fifth lens 650 can have a positive refractive power, while the first surface of the fifth lens 650 can be concave in the paraxial region, and the second surface of the fifth lens 650 can be convex in the paraxial region.

[0300] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 650. For example, the fifth lens 650 can have a first surface that is concave in the paraxial region and convex in a region other than the paraxial region. Further, the fifth lens 650 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0301] The sixth lens 660 can have a negative refractive power, while the first surface of the sixth lens 660 can be concave in the paraxial region.

[0302] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 660. For example, the first surface of the sixth lens 660 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 660 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0303] The seventh lens 670 can have a positive refractive power, and the first and second surfaces of the seventh lens 670 can be convex in the paraxial region.

[0304] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 670. For example, the seventh lens 670 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the seventh lens 670 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0305] The eighth lens 680 can have a negative refractive power, while the first surface of the eighth lens 680 can be concave in the paraxial region.

[0306] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 680. For example, the first surface of the eighth lens 680 can be convex in the paraxial region and concave in a region other than the paraxial region. The second surface of the eighth lens 680 can be concave in the paraxial region and convex in a region other than the paraxial region.

[0307] The first lens 610 can be formed of glass, and the second lens 620 through the eighth lens 680 can be formed of plastic. Further, the second lens 620 through the eighth lens 680 can each be formed of plastic having optical characteristics different from those of the adjacent lens.

[0308] For example, the first lens 610 can be formed of glass having a high dispersion value, and the second lens 620 and the fourth lens 640 can each be formed of plastic having a high refractive index and a low dispersion value.

[0309] Meanwhile, each surface of the first lens 610 through the eighth lens 680 can have an aspheric coefficient as shown in Table 18. In an example, the object side surface and the image side surface of the first lens 610 through the eighth lens 680 can each have an asphere.

[0310] Table 18

[0311]

[0312]

[0313] Further, the optical imaging system 600 configured as described above can have Figure 12 aberration characteristics as shown.

[0314] Reference Figure 13 and Figure 14 An optical imaging system 700 according to a seventh example is described.

[0315] The optical imaging system 700 according to the seventh example can include the first lens 710, the second lens 720, the third lens 730, the fourth lens 740, the fifth lens 750, the sixth lens 760, the seventh lens 770, and the eighth lens 780, and can further include the optical filter 790 and the image sensor IS including the imaging surface 791.

[0316] The optical imaging system 700 according to the seventh example can focus an image on the imaging surface 791. The imaging surface 791 can represent a surface on which a focus point is formed by the optical imaging system 700. For example, the imaging surface 791 can represent one surface of the image sensor IS on which light is received.

[0317] Tables 19 and 20 show the characteristics (e.g., the radius of curvature, the thickness of the lens or the distance between the lenses, the refractive index, the Abbe number, and the focal length) of each lens.

[0318] Table 19

[0319] Surface No. Item Radius of Curvature Thickness or Distance Refractive Index Abbe Number Focal Length S1 First Lens 1.957 0.676 1.497 81.6 5.62 S2 First Lens 5.738 0.125 S3 Second Lens 7.453 0.220 1.680 18.2 -18.62 S4 Second Lens 4.658 0.119 S5 Third Lens 6.529 0.305 1.535 55.7 14.65 S6 Third Lens 37.725 0.346 S7 Fourth Lens -57.373 0.226 1.650 21.5 -59.71 S8 Fourth Lens 124.486 0.309 S9 Fifth Lens 5.858 0.272 1.567 37.4 -26.5 S10 Fifth Lens 4.151 0.264 S11 Sixth Lens 6.121 0.393 1.544 56.0 4.78 S12 Sixth Lens -4.457 0.150 S13 Seventh Lens -6.120 0.220 1.635 24.0 -3188.08 S14 Seventh Lens -6.225 0.845 S15 Eighth Lens 26.246 0.280 1.535 55.7 -3.29 S16 Eighth Lens 1.652 0.250 S17 Filter Infinity 0.110 1.517 64.2 S18 Infinity 0.390 S19 Imaging Surface Infinity

[0320] Table 20

[0321] f 4.54 Y52 0.3176 IMG HT 5.107 Y62 0.4631 FOV 93.3 Y72 0.4479 SAG52 -0.5401 Y82 0.6045 SAG62 -0.7578 Z52 0.0098 SAG72 -0.6259 Z62 -0.02095 SAG82 -0.957 Z72 -0.01313 Z82 0.08195

[0322] In the seventh example, the first lens 710 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0323] The second lens 720 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0324] The third lens 730 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0325] The fourth lens 740 can have a negative refractive power, and a concave first surface and a second surface.

[0326] The fifth lens 750 can have a negative refractive power, while the first surface of the fifth lens 750 can be concave in the paraxial region.

[0327] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens 750. For example, the fifth lens 750 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the fifth lens 750 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0328] The sixth lens 760 can have a positive refractive power, and the first surface and the second surface can be convex in the paraxial region.

[0329] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 760. For example, the first surface of the sixth lens 760 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 760 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0330] The seventh lens 770 can have a negative refractive power, while the first surface of the seventh lens 770 can be concave in the paraxial region and the second surface of the seventh lens 770 can be convex in the paraxial region.

[0331] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 770. For example, the seventh lens 770 can have a first surface that is concave in the paraxial region and convex in a region other than the paraxial region. Further, the seventh lens 770 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0332] The eighth lens 780 can have a negative refractive power, while the first surface thereof can be concave in the paraxial region.

[0333] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 780. For example, the eighth lens 780 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 780 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0334] The first lens 710 can be formed of glass, and the second lens 720 to the eighth lens 780 can be formed of plastic. Further, the second lens 720 to the eighth lens 780 can each be formed of plastic having optical characteristics different from those of the adjacent lens.

[0335] For example, the first lens 710 can be formed of glass having a high dispersion value, and the second lens 720 and the fourth lens 740 can each be formed of plastic having a high refractive index and a low dispersion value.

[0336] Meanwhile, each surface of the first lens 710 to the eighth lens 780 can have an aspheric coefficient as shown in Table 21. For example, the object side surface and the image side surface of the first lens 710 to the eighth lens 780 can each be an aspheric surface.

[0337] Table 21

[0338]

[0339]

[0340] Further, the optical imaging system 700 configured as described above can have Figure 14 aberration characteristics as illustrated.

[0341] Referring to Figure 15 and Figure 16 An optical imaging system 800 according to an eighth example is described.

[0342] The optical imaging system 800 according to the eighth example can include a first lens 810, a second lens 820, a third lens 830, a fourth lens 840, a fifth lens 850, a sixth lens 860, a seventh lens 870, and an eighth lens 880, and can further include a filter 890 and an image sensor IS including an imaging surface 891.

[0343] The optical imaging system 800 according to the eighth example can focus an image on the imaging surface 891. The imaging surface 891 can represent a surface on which a focal point is formed by the optical imaging system 800. For example, the imaging surface 891 can represent one surface of the image sensor IS on which light is received.

[0344] Tables 22 and 23 show the characteristics (e.g., the radius of curvature, the thickness of the lens or the distance between the lenses, the refractive index, the Abbe number, and the focal length) of each lens.

[0345] Table 22

[0346]

[0347]

[0348] Table 23

[0349] f 4.49 Y52 0.3169 IMG HT 5.107 Y62 0.4841 FOV 93.8 Y72 0.4341 SAG52 -0.5667 Y82 0.5815 SAG62 -0.7286 Z52 0.01083 SAG72 -0.641 Z62 -0.02547 SAG82 -0.9926 Z72 -0.01247 Z82 0.07701

[0350] In the eighth example, the first lens 810 can have a positive refractive power and have a convex first surface and a concave second surface.

[0351] The second lens 820 can have a negative refractive power and have a convex first surface and a concave second surface.

[0352] The third lens 830 can have a positive refractive power and have a convex first surface and a concave second surface.

[0353] The fourth lens 840 can have a negative refractive power and a concave first surface and a second surface.

[0354] The fifth lens 850 can have a negative refractive power, while the first surface of the fifth lens 850 can be concave in the paraxial region.

[0355] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens 850. For example, the first surface of the fifth lens 850 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the fifth lens 850 can have a second surface that is concave in the paraxial region and can be convex in a region other than the paraxial region.

[0356] The sixth lens 860 can have a positive refractive power, and the first surface and the second surface of the sixth lens 860 can be convex in the paraxial region.

[0357] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the sixth lens 860. For example, the first surface of the sixth lens 860 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 860 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0358] The seventh lens 870 can have a negative refractive power, while the first surface of the seventh lens 870 can be concave in the paraxial region and the second surface of the seventh lens 870 can be convex in the paraxial region.

[0359] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the seventh lens 870. For example, the first surface of the seventh lens 870 can be concave in the paraxial region and convex in a region other than the paraxial region. Further, the seventh lens 870 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0360] The eighth lens 880 can have a negative refractive power, while the first surface of the eighth lens 880 can be concave in the paraxial region.

[0361] Further, at least one inflection point can be formed on at least one of the first surface and the second surface of the eighth lens 880. For example, the first surface of the eighth lens 880 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 880 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0362] The first lens 810 and the second lens 820 can be formed of glass, and the third lens 830 to the eighth lens 880 can be formed of plastic. Also, the third lens 830 to the eighth lens 880 can each be formed of plastic having optical characteristics different from those of the adjacent lens.

[0363] For example, the first lens 810 can be formed of glass having a high dispersion value, and the second lens 820 can be formed of glass having a high refractive index and a low dispersion value. The fourth lens 840 and the seventh lens 870 can each be formed of plastic having a high refractive index and a low dispersion value.

[0364] In an example, each surface of the first lens 810 to the eighth lens 880 can have an aspheric coefficient as shown in Table 24. For example, the object side surface and the image side surface of the first lens 810 to the eighth lens 880 can each have an asphere.

[0365] Table 24

[0366] S1 S2 S3 S4 S5 S6 S7 S8 K -1.785 -32.039 19.971 12.084 12.646 0.000 -99.000 -99.000 A 3.502E-02 -3.396E-02 -5.681E-02 2.307E-02 -3.095E-02 -3.355E-02 -5.437E-02 -7.047E-02 B -6.545E-02 2.708E-01 3.638E-01 -1.016E+00 3.415E-01 4.128E-01 -4.686E-01 -1.971E-01 C 3.650E-01 -1.865E+00 -2.842E+00 1.230E+01 -3.997E+00 -4.721E+00 5.193E+00 2.157E+00 D -1.447E+00 8.173E+00 1.559E+01 -9.465E+01 3.050E+01 3.426E+01 -3.429E+01 -1.155E+01 E 4.011E+00 -2.421E+01 -5.791E+01 5.012E+02 -1.579E+02 -1.685E+02 1.470E+02 3.901E+01 F -7.885E+00 5.031E+01 1.507E+02 -1.881E+03 5.747E+02 5.798E+02 -4.350E+02 -9.063E+01 G 1.109E+01 -7.512E+01 -2.819E+02 5.084E+03 -1.501E+03 -1.424E+03 9.150E+02 1.498E+02 H -1.122E+01 8.152E+01 3.838E+02 -9.972E+03 2.841E+03 2.522E+03 -1.387E+03 -1.789E+02 J 8.156E+00 -6.432E+01 -3.810E+02 1.417E+04 -3.899E+03 -3.222E+03 1.518E+03 1.545E+02 L -4.210E+00 3.648E+01 2.729E+02 -1.443E+04 3.835E+03 2.938E+03 -1.186E+03 -9.563E+01 M 1.504E+00 -1.447E+01 -1.373E+02 1.024E+04 -2.634E+03 -1.862E+03 6.443E+02 4.126E+01 N -3.529E-01 3.806E+00 4.604E+01 -4.813E+03 1.197E+03 7.795E+02 -2.307E+02 -1.178E+01 O 4.891E-02 -5.959E-01 -9.230E+00 1.344E+03 -3.238E+02 -1.935E+02 4.885E+01 1.995E+00 P -3.031E-03 4.200E-02 8.364E-01 -1.689E+02 3.939E+01 2.157E+01 -4.619E+00 -1.517E-01 S9 S10 S11 S12 S13 S14 S15 S16 K -41.861 -5.652 5.445 -10.894 -0.634 -15.398 11.180 -6.299 A -2.046E-01 -2.783E-01 -3.646E-02 9.292E-03 4.758E-02 6.316E-02 -2.467E-01 -1.390E-01 B 2.402E-01 4.192E-01 2.119E-01 3.231E-01 2.317E-01 5.835E-02 1.921E-01 1.169E-01 C -3.091E-01 -1.292E+00 -6.352E-01 -7.435E-01 -6.682E-01 -2.257E-01 -1.245E-01 -7.340E-02 D 9.498E-02 3.386E+00 1.096E+00 9.282E-01 8.677E-01 2.765E-01 6.037E-02 3.292E-02 E 1.205E+00 -6.611E+00 -1.349E+00 -7.824E-01 -6.871E-01 -1.916E-01 -2.040E-02 -1.051E-02 F -4.061E+00 9.523E+00 1.219E+00 4.840E-01 3.650E-01 8.403E-02 4.824E-03 2.399E-03 G 7.181E+00 -1.012E+01 -8.021E-01 -2.280E-01 -1.361E-01 -2.434E-02 -8.122E-04 -3.944E-04 H -8.225E+00 7.923E+00 3.806E-01 8.221E-02 3.609E-02 4.686E-03 9.860E-05 4.689E-05 J 6.458E+00 -4.535E+00 -1.290E-01 -2.234E-02 -6.659E-03 -5.767E-04 -8.651E-06 -4.026E-06 L -3.521E+00 1.869E+00 3.083E-02 4.459E-03 7.959E-04 3.856E-05 5.435E-07 2.467E-07 M 1.315E+00 -5.379E-01 -5.051E-03 -6.294E-04 -4.908E-05 -1.744E-07 -2.383E-08 -1.052E-08 N -3.211E-01 1.025E-01 5.389E-04 5.926E-05 -4.199E-07 -1.899E-07 6.922E-10 2.961E-10 O 4.624E-02 -1.160E-02 -3.364E-05 -3.332E-06 2.645E-07 1.400E-08 -1.196E-11 -4.948E-12 P -2.974E-03 5.911E-04 9.299E-07 8.457E-08 -1.188E-08 -3.426E-10 9.307E-14 3.717E-14

[0367] Also, the optical imaging system 800 configured as described above can have Figure 16 aberration characteristics as shown.

[0368] Referring to Figure 17 and Figure 18 An optical imaging system 900 according to a ninth example is described.

[0369] The optical imaging system 900 according to the ninth example can include a first lens 910, a second lens 920, a third lens 930, a fourth lens 940, a fifth lens 950, a sixth lens 960, a seventh lens 970, and an eighth lens 980, and can further include a filter 990 and an image sensor IS including an imaging surface 991.

[0370] The optical imaging system 900 according to the ninth example can focus an image on the imaging surface 991. The imaging surface 991 can represent a surface on which a focal point is formed by the optical imaging system 900. For example, the imaging surface 991 can represent one surface of the image sensor IS on which light is received.

[0371] Tables 25 and 26 show the characteristics (e.g., the radius of curvature, the thickness of the lens or the distance between the lenses, the refractive index, the Abbe number, and the focal length) of each lens.

[0372] Table 25

[0373] Surface No. Item Radius of Curvature Thickness or Distance Refractive Index Abbe Number Focal Length S1 First Lens 1.921 0.689 1.497 81.6 5.37 S2 First Lens 5.995 0.100 S3 Second Lens 8.011 0.220 1.755 27.5 -12.68 S4 Second Lens 4.327 0.116 S5 Third Lens 6.405 0.324 1.564 60.8 12.5 S6 Third Lens 66.198 0.340 S7 Fourth Lens -63.481 0.220 1.650 21.5 89891.63 S8 Fourth Lens -63.500 0.340 S9 Fifth Lens 7.264 0.220 1.567 37.4 -18.07 S10 Fifth Lens 4.216 0.240 S11 Sixth Lens 6.104 0.439 1.544 56.0 4.44 S12 Sixth Lens -3.922 0.150 S13 Seventh Lens -5.924 0.285 1.635 24.0 -70.65 S14 Seventh Lens -6.943 0.900 S15 Eighth Lens 63.531 0.226 1.535 55.7 -3.26 S16 Eighth Lens 1.700 0.250 S17 Filter Infinity 0.110 1.517 64.2 S18 Infinity 0.332 S19 Imaging Surface Infinity

[0374] Table 26

[0375]

[0376]

[0377] In a ninth example, the first lens 910 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0378] The second lens 920 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0379] The third lens 930 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0380] The fourth lens 940 can have a positive refractive power, and have a concave first surface and a convex second surface.

[0381] The fifth lens 950 can have a negative refractive power, while the first surface of the fifth lens 950 can be concave in the paraxial region.

[0382] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 950. For example, the fifth lens 950 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the fifth lens 950 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0383] The sixth lens 960 can have a positive refractive power, and the first and second surfaces of the sixth lens 960 can be convex in the paraxial region.

[0384] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 960. For example, the first surface of the sixth lens 960 can be convex in the paraxial region, and concave in a region other than the paraxial region. Further, the sixth lens 960 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0385] The seventh lens 970 can have a negative refractive power, while the first surface of the seventh lens 970 can be concave in the paraxial region, and the second surface thereof can be convex in the paraxial region.

[0386] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 970. For example, the seventh lens 970 can have a first surface that is concave in the paraxial region and convex in a region other than the paraxial region. Further, the seventh lens 970 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0387] The eighth lens 980 can have a negative refractive power, while the first surface of the eighth lens 980 can be concave in the paraxial region.

[0388] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 980. For example, the eighth lens 980 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 980 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0389] The first to third lenses 910 to 930 can each be formed of glass, and the fourth to eighth lenses 940 to 980 can each be formed of plastic. Further, the fourth to eighth lenses 940 to 980 can each be formed of plastic having optical characteristics different from those of the adjacent lens.

[0390] For example, the first lens 910 can be formed of glass having a high dispersion value, the second lens 920 can be formed of glass having a high refractive index and a low dispersion value, and the third lens 930 can be formed of glass having a high dispersion value. The fourth lens 940 and the seventh lens 970 can each be formed of plastic having a high refractive index and a low dispersion value.

[0391] In an example, each surface of the first to eighth lenses 910 to 980 can have aspherical coefficients as shown in Table 27. For example, the object side surface and the image side surface of the first to eighth lenses 910 to 980 can each be an aspherical surface.

[0392] Table 27

[0393]

[0394]

[0395] Further, the optical imaging system 900 configured as described above can have Figure 18 aberration characteristics as shown.

[0396] Referring to Figure 19 and Figure 20 An optical imaging system 1000 according to a tenth example is described.

[0397] The optical imaging system 1000 according to the tenth example can include a first lens 1010, a second lens 1020, a third lens 1030, a fourth lens 1040, a fifth lens 1050, a sixth lens 1060, a seventh lens 1070, and an eighth lens 1080, and can further include a filter 1090 and an image sensor IS including an imaging surface 1091.

[0398] The optical imaging system 1000 according to the tenth example can focus an image on an imaging surface 1091. The imaging surface 1091 can represent a surface on which a focal point is formed by the optical imaging system 1000. For example, the imaging surface 1091 can represent one surface of the image sensor IS on which light is received.

[0399] Tables 28 and 29 show characteristics (e.g., a radius of curvature, a thickness of a lens or a distance between lenses, a refractive index, an Abbe number, and a focal length) of each lens.

[0400] Table 28

[0401]

[0402]

[0403] Table 29

[0404] f 4.32 Y52 0.3597 IMG HT 5.107 Y62 0.6427 FOV 96.1 Y72 0.335 SAG52 -0.408 Y82 0.6852 SAG62 -0.7106 Z52 0.01144 SAG72 -0.4527 Z62 -0.04308 SAG82 -0.9839 Z72 -0.00332 Z82 0.09726

[0405] In the tenth example, the first lens 1010 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0406] The second lens 1020 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0407] The third lens 1030 can have a negative refractive power, and have a convex first surface and a concave second surface.

[0408] The fourth lens 1040 can have a positive refractive power, and have a convex first surface and a concave second surface.

[0409] The fifth lens 1050 can have a negative refractive power, while the first surface of the fifth lens 1050 can be concave in a paraxial region.

[0410] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 1050. For example, the fifth lens 1050 can have a first surface that is convex in a paraxial region and concave in a region other than the paraxial region. Further, the fifth lens 1050 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0411] The sixth lens 1060 can have a positive refractive power, and the first and second surfaces can be convex in a paraxial region.

[0412] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 1060. For example, the first surface of the sixth lens 1060 can be convex in the paraxial region and concave in a region other than the paraxial region. Further, the sixth lens 1060 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0413] The seventh lens 1070 can have a negative refractive power, while the first surface of the seventh lens 1070 can be concave in the paraxial region and the second surface of the seventh lens 1070 can be convex in the paraxial region.

[0414] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 1070. For example, the seventh lens 1070 can have a first surface that is concave in the paraxial region and convex in a region other than the paraxial region. Further, the seventh lens 1070 can have a second surface that is convex in the paraxial region and can be concave in a region other than the paraxial region.

[0415] The eighth lens 1080 can have a negative refractive power, while the first surface of the eighth lens 1080 can be concave in the paraxial region.

[0416] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the eighth lens 1080. For example, the eighth lens 1080 can have a first surface that is convex in the paraxial region and concave in a region other than the paraxial region. Further, the eighth lens 1080 can have a second surface that is concave in the paraxial region and convex in a region other than the paraxial region.

[0417] The first to fourth lenses 1010 to 1040 can each be formed of glass, and the fifth to eighth lenses 1050 to 1080 can each be formed of plastic. Further, the fifth to eighth lenses 1050 to 1080 can each be formed of plastic having optical characteristics different from those of the adjacent lenses.

[0418] For example, the first lens 1010 can be formed of glass having a high dispersion value, the second and fourth lenses 1020 and 1040 can each be formed of glass having a high refractive index and a low dispersion value, and the third lens 1030 can be formed of glass having a high dispersion value. The seventh lens 1070 can be formed of plastic having a high refractive index and a low dispersion value.

[0419] In the example, each surface of the first lens 1010 to the eighth lens 1080 may have aspherical coefficients as shown in Table 30. For example, both the object-side surface and the image-side surface of the first lens 1010 to the eighth lens 1080 may be aspherical.

[0420] Table 30

[0421]

[0422]

[0423] Furthermore, the optical imaging system 1000 configured as described above may have Figure 20 The aberration characteristics shown.

[0424] As described above, optical imaging systems based on one or more examples can achieve high resolution and have a small overall length.

[0425] While this disclosure includes specific examples, it will be apparent upon understanding the disclosure of this application that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be understood in a descriptive sense only and not for limiting purposes. The description of features or aspects in each example should be considered applicable to similar features or aspects in other examples. Suitable results may still be achieved if the described techniques are performed with components in the described system, architecture, device, or circuit having different orders, and / or if components are combined in different ways and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of this disclosure is not limited by the specific embodiments but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents should be understood to be included in this disclosure.

Claims

1. An optical imaging system comprising: first, second, third, fourth, fifth, sixth, seventh, and eighth lenses arranged in order from an object side to an imaging side, wherein the first lens has a positive refractive power and the second lens has a negative refractive power, and the eighth lens has a negative refractive power, wherein the third lens has a positive refractive power, the fourth lens has a negative refractive power, the fifth lens has a negative refractive power, and at least one of the sixth and seventh lenses has a positive refractive power, or the third lens has a positive refractive power, the fourth lens has a positive refractive power, the fifth lens has a negative refractive power, and the sixth and seventh lenses have opposite refractive powers, or the third lens has a positive refractive power, and the fifth to seventh lenses have positive, negative, and positive refractive powers, respectively, or the third lens has a negative refractive power, and the fourth to seventh lenses have positive, negative, positive, and negative refractive powers, respectively, wherein paraxial regions of the object side and image side surfaces of the first lens have convex and concave shapes, respectively, paraxial regions of the object side and image side surfaces of the second lens have convex and concave shapes, respectively, paraxial regions of the object side and image side surfaces of the third lens have convex and concave shapes, respectively, a paraxial region of at least one of the object side and image side surfaces of the fourth lens has a concave shape, paraxial regions of the object side and image side surfaces of the fifth lens have convex and concave shapes or concave and convex shapes, respectively, a paraxial region of the object side surface of the sixth lens has a convex shape, a paraxial region of the image side surface of the seventh lens has a convex shape, and paraxial regions of the object side and image side surfaces of the eighth lens have convex and concave shapes, respectively, wherein at least one of the first to eighth lenses is formed of glass, and the remaining lenses are formed of plastic, wherein 5.498 / (2x5.107) ≤ TTL / (2xIMG HT) < 0.6 is satisfied, where TTL represents a distance on an optical axis from the object side surface of the first lens to an imaging surface, and IMG HT represents half of a diagonal length of the imaging surface, wherein at least one of the first to eighth lenses includes an aspherical surface, and the number of lenses having refractive powers in the optical imaging system is eight.

2. The optical imaging system of claim 1, wherein, at least one of -0.2 < SAG52 / TTL < 0, -0.2 < SAG62 / TTL < 0, -0.3 < SAG72 / TTL < 0, and -0.3 < SAG82 / TTL < 0 is satisfied, where SAG52 represents a distance in the optical axis direction from an end of an effective diameter of an image side surface of the fifth lens to a vertex of the image side surface of the fifth lens in the optical axis direction, SAG62 represents a distance in the optical axis direction from an end of an effective diameter of an image side surface of the sixth lens to a vertex of the image side surface of the sixth lens in the optical axis direction, SAG72 represents a distance in the optical axis direction from an end of an effective diameter of an image side surface of the seventh lens to a vertex of the image side surface of the seventh lens in the optical axis direction, and SAG82 represents a distance in the optical axis direction from an end of an effective diameter of an image side surface of the eighth lens to a vertex of the image side surface of the eighth lens in the optical axis direction.

3. The optical imaging system of claim 1, wherein, at least one of 40 < v1-v2 < 70, 30 < v1-v4 < 70, and 20 < v1-(v6+v7) / 2 < 50 is satisfied, where v1 represents an Abbe number of the first lens, v2 represents an Abbe number of the second lens, v4 represents an Abbe number of the fourth lens, v6 represents an Abbe number of the sixth lens, and v7 represents an Abbe number of the seventh lens.

4. The optical imaging system of claim 3, wherein, the first lens is formed of a glass having an Abbe number greater than 70.

5. The optical imaging system of claim 3, wherein, the Abbe number of the first lens is the largest among the Abbe numbers of the first lens to the eighth lens, and the second lens and the fourth lens are each formed of one of a glass and a plastic having a refractive index greater than 1.65 and an Abbe number less than 22.

6. The optical imaging system of claim 1, wherein, 0 < f1 / f < 1.4 is satisfied, where f represents a total focal length of the optical imaging system, and f1 represents a focal length of the first lens.

7. The optical imaging system of claim 1, wherein, -10 < f2 / f < -1 is satisfied, where f represents a total focal length of the optical imaging system, and f2 represents a focal length of the second lens.

8. The optical imaging system of claim 1, wherein, 0 < |f3 / f| / 10 < 30 is satisfied, where f represents a total focal length of the optical imaging system, and f3 represents a focal length of the third lens.

9. The optical imaging system of claim 1, wherein, 0.5 < |f6 / f| < 10 is satisfied, where f represents a total focal length of the optical imaging system, and f6 represents a focal length of the sixth lens.

10. The optical imaging system of claim 1, wherein, -3 < f8 / f < 0 is satisfied, where f represents a total focal length of the optical imaging system, and f8 represents a focal length of the eighth lens.

11. The optical imaging system of claim 1, wherein, 5.501 / 4.56 ≤ TTL / f < 1.4 and 0.535 / 4.32 ≤ BFL / f < 0.3 are satisfied, where f represents a total focal length of the optical imaging system, and BFL represents a distance in the optical axis from an image side surface of the eighth lens to the imaging surface.

12. The optical imaging system of claim 1, wherein, 0.100 / 4.55 ≤ D1 / f ≤ 0.127 / 4.53 is satisfied, where D1 represents a distance on the optical axis between an image-side surface of the first lens and an object-side surface of the second lens, and f represents a total focal length of the optical imaging system.

13. The optical imaging system of claim 1, wherein, 93x(5.107 / 4.56)° ≤ FOVx(IMG HT / f) ≤ 96.1x(5.107 / 4.32)° is satisfied, where f represents a total focal length of the optical imaging system, and FOV represents a field of view of the optical imaging system.

14. The optical imaging system of claim 1, wherein, the fifth lens has at least one inflection point on an image-side surface thereof, and 2 < |Y52 / Z52| < 50 is satisfied, where Y52 represents a perpendicular height between a first inflection point of the image-side surface of the fifth lens and the optical axis, and Z52 represents a distance in the optical axis direction from the first inflection point of the image-side surface of the fifth lens to a vertex in the optical axis direction of the image-side surface of the fifth lens.

15. The optical imaging system of claim 1, wherein, the sixth lens has at least one inflection point on an image-side surface thereof, and 3 < |Y62 / Z62| < 50 is satisfied, where Y62 represents a perpendicular height between a first inflection point of the image-side surface of the sixth lens and the optical axis, and Z62 represents a distance in the optical axis direction from the first inflection point of the image-side surface of the sixth lens to a vertex in the optical axis direction of the image-side surface of the sixth lens.

16. The optical imaging system of claim 1, wherein, the seventh lens has at least one inflection point on an image-side surface thereof, and 5 < |Y72 / Z72| < 120 is satisfied, where Y72 represents a perpendicular height between a first inflection point of the image-side surface of the seventh lens and the optical axis, and Z72 represents a distance in the optical axis direction from the first inflection point of the image-side surface of the seventh lens to a vertex in the optical axis direction of the image-side surface of the seventh lens.

17. The optical imaging system of claim 1, wherein, the eighth lens has at least one inflection point on an image-side surface thereof, and 2 < |Y82 / Z82| < 30 is satisfied, where Y82 represents a perpendicular height between a first inflection point of the image-side surface of the eighth lens and the optical axis, and Z82 represents a distance in the optical axis direction from the first inflection point of the image-side surface of the eighth lens to a vertex in the optical axis direction of the image-side surface of the eighth lens.

Images