Optical imaging system

Abstract

An optical imaging system includes, in order from an object side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, wherein the first lens has a positive refractive power, and the second lens has a negative refractive power, and wherein 0.5 < TTL / (2 x ImgHT) < 0.67 is satisfied, where TTL is a distance on an optical axis from an object side surface of the first lens to an image plane, and ImgHT is half of a diagonal length of the image plane.

Description

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[0010] ,

[0009] Cross - reference to related applications

[0002] This application claims the priority benefit of Korean Patent Application No. 10 - 2021 - 0111843, filed on August 24, 2021, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical field

[0003] Exemplary embodiments of the present disclosure relate to an optical imaging system. Background art

[0004] A portable terminal may include a camera that includes an optical imaging system having a plurality of lenses to perform video calls and image capturing.

[0005] As the functions occupied by the camera in the portable terminal gradually increase, the demand for cameras of portable terminals with high resolution increases.

[0006] Image sensors having a high pixel count (e.g., 13 million to 100 million pixels, etc.) may be used in the cameras of portable terminals to achieve improved image quality.

[0007] In addition, since a portable terminal can be designed to have a small size, the camera for the portable terminal can also be designed to have a reduced size, and thus, it may be desirable to develop an optical imaging system having a reduced size and capable of achieving high resolution.

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

[0009] The Summary of the Invention section is provided to introduce, in brief form, selections of inventive concepts, which will be further described in the Detailed Description section below. The Summary of the Invention section is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to assist in determining the scope of the claimed subject matter. <00000​​

[0011] ImgHT can be greater than 4.5 mm (millimeters) and less than 6.5 mm.

[0012] TTL / ∑CT can be less than 2.97, where ∑CT is a sum of thicknesses of the first lens through the seventh lens on the optical axis.

[0013] f / f4 can be greater than -0.2 and less than 0, where f is a total focal length of the optical imaging system, and f4 is a focal length of the fourth lens.

[0014] v1-v2 can be less than 38 and n2+n4 can be greater than 3.3, where v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, n2 is a refractive index of the second lens, and n4 is a refractive index of the fourth lens.

[0015] TTL / f can be less than 1.205 and BFL / f can be less than 0.21, where BFL is a distance on the optical axis from an image side surface of the seventh lens to the image plane.

[0016] CT4 / f4 can be greater than -0.02 and less than 0, where CT4 is a thickness of the fourth lens on the optical axis.

[0017] R8 / f4 can be greater than -0.5 and less than 0, where R8 is a radius of curvature of the image side surface of the fourth lens.

[0018] SWG42 can be greater than -20° and less than or equal to -2.9°, where SWG42 is a grazing angle at a point of a maximum effective diameter of the image side surface of the fourth lens.

[0019] SWG41_0.3 can be greater than 0° and less than 1.1°, where SWG41_0.3 is a grazing angle at a point of a maximum effective diameter x 0.3 of the object side surface of the fourth lens.

[0020] SWG42_0.2 can be greater than -0.5° and less than 0.6°, where SWG42_0.2 is a grazing angle at a point of a maximum effective diameter x 0.2 of the image side surface of the fourth lens.

[0021] SWG31_0.5 can be greater than -3° and less than or equal to 3°, where SWG31_0.5 is a grazing angle at a point of a maximum effective diameter x 0.5 of the object side surface of the third lens.

[0022] SWG31_0.2 can be greater than -1° and less than 2°, where SWG31_0.2 is a grazing angle at a point of a maximum effective diameter x 0.2 of the object side surface of the third lens.

[0023] |f1 / f2| can be greater than 0.3 and less than 0.45, where f1 is a focal length of the first lens and f2 is a focal length of the second lens.

[0024] |f345| can be greater than 20 mm and less than 120 mm and |f345| / f can be greater than 4 and less than 25, where f345 is a combined focal length of the third lens to the fifth lens.

[0025] The third lens can have a positive refractive power, the fourth lens can have a negative refractive power, the fifth lens can have a negative refractive power, the sixth lens can have a positive refractive power, and the seventh lens can have a negative refractive power.

[0026] In another general aspect, an optical imaging system includes a first lens having a positive refractive power, a second lens having a negative refractive power, a third lens having a refractive power, a fourth lens having a refractive power, a fifth lens having a refractive power, a sixth lens having a positive refractive power and a concave image side, and a seventh lens having a refractive power and a concave object side, where the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are sequentially disposed from an object side, and where -0.2 < f / f4 < 0 is satisfied, where f is a total focal length of the optical imaging system and f4 is a focal length of the fourth lens.

[0027] TTL / (2 x ImgHT) can be greater than 0.5 and less than 0.67.

[0028] In another general aspect, an optical imaging system includes a first lens having a positive refractive power, a second lens having a negative refractive power and a concave object side, a third lens having a refractive power, a fourth lens having a refractive power, a fifth lens having a refractive power, a sixth lens having a refractive power, and a seventh lens having a refractive power, where the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are sequentially disposed from an object side, and where v1-v2 < 38 and n2+n4 > 3.3 are satisfied, where v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, n2 is a refractive index of the second lens, and n4 is a refractive index of the fourth lens.

[0029] Other features and aspects will become apparent from the following detailed description, the accompanying drawings, and the claims. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 FIG. 1 is a diagram illustrating an optical imaging system according to a first exemplary embodiment of the present disclosure.

[0031] Figure 2 is a diagram illustrating Figure 1 aberration characteristics of the optical imaging system shown.

[0032] Figure 3 is a diagram showing an optical imaging system according to a second example embodiment of the present disclosure.

[0033] Figure 4 is a diagram showing Figure 3 aberration characteristics of the optical imaging system shown.

[0034] Figure 5 is a diagram showing an optical imaging system according to a third example embodiment of the present disclosure.

[0035] Figure 6 is a diagram showing Figure 5 aberration characteristics of the optical imaging system shown.

[0036] Figure 7 is a diagram showing an optical imaging system according to a fourth example embodiment of the present disclosure.

[0037] Figure 8 is a diagram showing Figure 7 aberration characteristics of the optical imaging system shown.

[0038] Figure 9 is a diagram showing an optical imaging system according to a fifth example embodiment of the present disclosure.

[0039] Figure 10 is a diagram showing Figure 9 aberration characteristics of the optical imaging system shown.

[0040] Figure 11 is a diagram showing an optical imaging system according to a sixth example embodiment of the present disclosure.

[0041] Figure 12 is a diagram showing Figure 11 aberration characteristics of the optical imaging system shown.

[0042] Figure 13 is a diagram showing an optical imaging system according to a seventh example embodiment of the present disclosure.

[0043] Figure 14 is a diagram showing Figure 13 aberration characteristics of the optical imaging system shown.

[0044] Figure 15 is a diagram showing an optical imaging system according to an eighth example embodiment of the present disclosure.

[0045] Figure 16 is a diagram showing Figure 15 aberration characteristics of the optical imaging system shown.

[0046] Figure 17is a graph showing a grazing angle at a predetermined position on a lens surface.

[0047] In all the drawings and specific embodiments, like reference numerals refer to like elements throughout. The drawings can not be to scale and the relative dimensions, proportions and depiction of elements in the drawings can be exaggerated for clarity, illustration and convenience. DETAILED DESCRIPTION

[0048] Hereinafter, although exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the examples are not limited thereto.

[0049] The following detailed description is provided to help the reader obtain a thorough understanding of the methods, devices, and / or systems described herein. However, various changes, modifications, and equivalents, which will be apparent to those skilled in the art, can be made in the methods, devices, and / or systems described herein without departing from the disclosure. For example, the order of the operations described herein should be construed as merely an example, and not a limitation of the order in which the operations are performed, except where a particular order is necessary for the operation to occur, and changes can be made in the order of the operations without departing from the disclosure. Also, descriptions of functions that are well known, in order to make the description more concise and focused, can be omitted.

[0050] The features described herein can be embodied in different forms, and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided solely for the purposes of illustrating a few of the many possible manners in which the methods, devices, and / or systems described herein can be implemented in light of the disclosure.

[0051] 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.

[0052] As used herein, the term "and / or" includes any one of the associated listed items, as well as any combination of any two or more of the associated listed items; likewise, "at least one of" includes any one of the associated listed items, as well as any combination of any two or more of the associated listed items.

[0053] Although terminology can be used in this disclosure, such as "first," "second," and "third," to describe various components, assemblies, regions, layers or sections, these terminologies are used only to distinguish one component, assembly, region, layer or section from another. More specifically, these terminologies are used to distinguish one component, assembly, region, layer or section from another component, assembly, region, layer or section. Thus, a first component, assembly, region, layer or section referred to in an example can also be termed a second component, assembly, region, layer or section without departing from the teachings of the examples described herein.

[0054] Spatially relative terms such as "upper," "lower," "over," "under," "left," "right," and the like can be used herein for description purposes to describe one element's relationship to another element encompassing various orientations of the device. The terms "upper" and "lower" are used in this disclosure to describe the relative position of one element to another element as shown in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation, for example, if the device is turned over. For example, if the device is turned over, the element described as on top of or above another element would now be oriented below that element. Accordingly, the term "above" encompasses both an orientation of above and below. The device can be otherwise oriented (for example, rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0055] The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the present disclosure. Unless otherwise defined, articles "a," "one" and "the" are intended to include plural references, the language of which is used only in the sense to provide that when there are two or more such modular components, elements, etc., any one or more of the two or more such modular components, elements, etc. can be used. The terms "including" and "comprising" are used herein in the sense of "including at least the recited feature but not excluding others."

[0056] Due to manufacturing techniques and / or tolerances, the shapes might vary slightly from the shapes depicted in the figures. Therefore, the examples described herein are not limited to the particular shapes described in the figures, but include deviations in shapes that occur due to manufacturing techniques.

[0057] In this document, the use of the phrase "can" (e.g., about an example can include or implement something) means that at least one example includes or implements the feature, and that the example is not limited in this regard to that example alone.

[0058] Features of the examples described herein can be combined in various ways as will be apparent after an understanding of the principles of the disclosure. Also, although example are described herein with a certain degree of specificity, it is to be understood that the disclosure can be practiced with variation of form and detail as will be apparent to those skilled in the art, given the benefit of this disclosure. In addition, although examples are described herein with a certain degree of specificity, it is to be understood that other configurations are possible.

[0059] An effective aperture radius of a lens surface is a radius of a portion of the lens surface through which light actually passes, and is not necessarily a radius of an outer edge of the lens surface. An object side surface of a lens and an image side surface of the lens can have different effective aperture radii.

[0060] In other words, the effective aperture radius of a lens surface is a distance between an optical axis of the lens surface and an edge ray of light passing through the lens surface in a direction perpendicular to the optical axis of the lens surface.

[0061] One or more exemplary embodiments of the disclosure provide an optical imaging system that can achieve high resolution and can have a reduced length.

[0062] In a lens diagram, a thickness, a size, and a shape of a lens can be exaggerated, and in particular, a shape of a spherical or aspherical surface presented in a lens diagram is merely an example, and is not limited thereto.

[0063] The first lens can refer to a lens closest to an object side, and the seventh lens can refer to a lens closest to an imaging surface (or an image sensor).

[0064] Further, in each lens, the first surface can refer to a surface close to an object side (or can refer to an object side surface), and the second surface can refer to a surface close to an image side (or can refer to an image side surface). Further, in exemplary embodiments, a curvature radius, a thickness, a distance, and a focal length of a lens are expressed in millimeters (mm), and a field of view is expressed in degrees.

[0065] In a description of a shape of each lens, a configuration in which one surface is convex indicates that a paraxial region portion of the surface is convex, a configuration in which one surface is concave indicates that a paraxial region portion of the surface is concave, and a configuration in which one surface is flat indicates that a paraxial region portion of the surface is flat. Accordingly, when one surface of a lens is described as convex, an edge portion of the lens can be concave. Similarly, when one surface of a lens is described as concave, an edge portion of the lens can be convex. Further, when one surface of a lens is described as flat, an edge portion of the lens can be convex or concave.

[0066] A paraxial region can refer to a narrow region adjacent to an optical axis.

[0067] An imaging surface can refer to a virtual plane on which a focus is formed by an optical imaging system. Alternatively, the imaging surface can refer to one surface of an image sensor on which light is received.

[0068] The optical imaging system in the exemplary embodiment can include seven lenses.

[0069] For example, the optical imaging system in the exemplary embodiment can include, in order from the object side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. The first lens to the seventh lens can be spaced apart from each other by a predetermined distance along the optical axis.

[0070] However, the optical imaging system in the exemplary embodiment can not only include seven lenses, and if necessary, can include other components.

[0071] For example, the optical imaging system can further include an image sensor for converting an image of an incident object into an electrical signal.

[0072] Further, the optical imaging system can further include an infrared filter (hereinafter referred to as a "filter") for blocking infrared rays. The filter can be disposed between the seventh lens and the image sensor.

[0073] Further, the optical imaging system can further include a diaphragm for adjusting the amount of light.

[0074] In the exemplary embodiment, the first lens to the seventh lens included in the optical imaging system can be formed of a plastic material.

[0075] Also, at least one of the first lens to the seventh lens can have an aspherical surface. Further, each of the first lens to the seventh lens can have at least one aspherical surface.

[0076] That is, at least one of the first surface and the second surface of the first lens to the seventh lens can be aspherical. The aspherical surface of the first lens to the seventh lens can be represented by Equation 1.

[0077] Equation 1

[0078]

[0079] In Equation 1, c is a curvature of the lens (an inverse of a radius of curvature), K is a conic constant, and Y is a distance from an arbitrary point on the aspherical surface of the lens to the optical axis. Also, the constants A to H, J, and L to P are aspherical coefficients. Z is a distance along the optical axis from the arbitrary point on the aspherical surface of the lens to the vertex of the aspherical surface.

[0080] The optical imaging system including the first lens to the seventh lens can have, in order from the object side, positive / negative / positive / negative / negative / positive / negative refractive power.

[0081] The optical imaging system in the exemplary embodiment can satisfy at least one of the following conditional expressions:

[0082] (Conditional Expression 1) TTL / ∑CT < 2.97

[0083] (Conditional Expression 2) -0.2 < f / f4 < 0

[0084] (Conditional Expression 3) v1-v2 < 38

[0085] (Conditional Expression 4) TTL / f < 1.205

[0086] (Conditional Expression 5) n2+n4 > 3.3

[0087] (Conditional Expression 6) BFL / f < 0.21

[0088] (Conditional Expression 7) -0.02 < CT4 / f4 < 0

[0089] (Conditional Expression 8) -0.5 < R8 / f4 < 0

[0090] (Conditional Expression 9) -20° < SWG42 ≤ -2.9°

[0091] (Conditional Expression 10) 0° < SWG41 < 0.3 < 1.1°

[0092] (Conditional Expression 11) -0.5° < SWG42 < 0.2 < 0.6°

[0093] (Conditional Expression 12) -3° < SWG31 < 0.5 ≤ 3°

[0094] (Conditional Expression 13) -1° < SWG31 < 0.2 < 2°

[0095] (Conditional Expression 14) 0.5 < TTL / (2×ImgHT) < 0.67

[0096] (Conditional Expression 15) 4.5 mm < ImgHT < 6.5 mm

[0097] (Conditional Expression 16) 0.3 < |f1 / f2| < 0.45

[0098] (Conditional Expression 17) 20 mm < |f345| < 120 mm

[0099] (Conditional Expression 18) 4 < |f345| / f < 25

[0100] In the conditional expression, f is a total focal length of the optical imaging system, f1 is a focal length of the first lens, f2 is a focal length of the second lens, f3 is a focal length of the third lens, f4 is a focal length of the fourth lens, f5 is a focal length of the fifth lens, and f345 is a combined focal length of the third lens to the fifth lens.

[0101] v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, n2 is a refractive index of the second lens, and n4 is a refractive index of the fourth lens.

[0102] TTL is a distance on the optical axis from an object side surface of the first lens to an image plane, and BFL is a distance on the optical axis from an image side surface of the seventh lens to the image plane.

[0103] ∑CT is a sum of thicknesses of the lenses on the optical axis, and CT4 is a thickness of the fourth lens on the optical axis.

[0104] R8 is a radius of curvature of the image side surface of the fourth lens, and ImgHT is half of a diagonal length of the image plane.

[0105] SWG31_0.2 is a grazing angle at a point of 0.2 times a maximum effective diameter of the object side surface of the third lens, and SWG31_0.5 is a grazing angle at a point of 0.5 times the maximum effective diameter of the object side surface of the third lens.

[0106] SWG41_0.3 is a grazing angle at a point of 0.3 times a maximum effective diameter of the object side surface of the fourth lens, SWG42_0.2 is a grazing angle at a point of 0.2 times a maximum effective diameter of the image side surface of the fourth lens, and SWG42 is a grazing angle at a point of a maximum effective diameter of the image side surface of the fourth lens.

[0107] Referring to Figure 17 , a grazing angle at a specific position on a lens surface is shown. For example, a grazing angle at a specific position on the object side surface of the third lens can be defined as an angle between a tangent line TL1 at an apex of the object side surface and a tangent line TL2 at the specific position.

[0108] When the object side surface of the lens is convex, the grazing angle can have a positive value, and when the object side surface of the lens is concave, the grazing angle can have a negative value.

[0109] In addition, when the image side surface of the lens is convex, the grazing angle can have a negative value, and when the image side surface of the lens is concave, the grazing angle can have a positive value.

[0110] The first lens to the seventh lens included in the optical imaging system in the exemplary embodiment will be described below.

[0111] The first lens can have a positive refractive power. Also, the first lens can have a meniscus shape convex toward the object side. In more detail, the first surface of the first lens can be convex, and the second surface of the first lens can be concave.

[0112] At least one of the first surface and the second surface of the first lens can be aspherical. For example, both surfaces of the first lens can be aspherical.

[0113] The second lens can have a negative refractive power. Also, the second lens can have a meniscus shape convex toward the object side. In more detail, the first surface of the second lens can be convex, and the second surface of the second lens can be concave.

[0114] Alternatively, both surfaces of the second lens can be concave. In more detail, both the first surface and the second surface of the second lens can be concave.

[0115] 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.

[0116] The third lens can have a positive refractive power. Also, the third lens can have a meniscus shape convex toward the image side. In more detail, the first surface of the third lens can be concave, and the second surface of the third lens can be convex.

[0117] Alternatively, the third lens can have a meniscus shape convex toward the object side. In more detail, the first surface of the third lens can be convex, and the second surface of the third lens can be concave.

[0118] 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.

[0119] The fourth lens can have a negative refractive power. Also, the fourth lens can have a meniscus shape convex toward the object side. In more detail, the first surface of the fourth lens can be convex, and the second surface of the fourth lens can be concave.

[0120] At least one of the first surface and the second surface of the fourth lens can be aspherical. For example, both surfaces of the fourth lens can be aspherical.

[0121] At least one inflection point can be formed on at least one of the first surface and the second surface of the fourth lens. For example, the first surface of the fourth lens can be convex in a paraxial region, and can be concave in a portion other than the paraxial region. The second surface of the fourth lens can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0122] The fifth lens can have a negative refractive power. Also, the fifth lens can have a meniscus shape convex toward the object side. In more detail, the first surface of the fifth lens can be convex in the paraxial region, and the second surface of the fifth lens can be concave in the paraxial region.

[0123] At least one of the first surface and the second surface of the fifth lens can be aspherical. For example, both surfaces of the fifth lens can be aspherical.

[0124] At least one inflection point can be formed on at least one of the first surface and the second surface of the fifth lens. For example, the first surface of the fifth lens can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. The second surface of the fifth lens can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0125] The sixth lens can have a positive refractive power. Also, the sixth lens can have a meniscus shape convex toward the object side. In more detail, the first surface of the sixth lens can be convex in the paraxial region, and the second surface can be concave in the paraxial region.

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

[0127] At least one inflection point can be formed on at least one of the first surface and the second surface of the sixth lens. For example, the first surface of the sixth lens can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. The second surface of the sixth lens can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0128] The seventh lens can have a negative refractive power. Also, both surfaces of the seventh lens can be concave. In more detail, the first surface and the second surface of the seventh lens can be concave in the paraxial region.

[0129] At least one of the first surface and the second surface of the seventh lens can be aspherical. For example, both surfaces of the seventh lens can be aspherical.

[0130] Also, at least one inflection point can be formed on at least one of the first surface and the second surface of the seventh lens. For example, the first surface of the seventh lens can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. The second surface of the seventh lens can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0131] Each of the first to fifth lenses can be formed of a plastic material having optical characteristics different from those of an adjacent lens.

[0132] At least two lenses among the first to seventh lenses can have a refractive index greater than 1.66.

[0133] The lens having a negative refractive power among the first to fourth lenses can have a refractive index greater than 1.66. For example, the second lens and the fourth lens can have a negative refractive power and a refractive index greater than 1.66.

[0134] The absolute value of the focal length of each of the third to fifth lenses can be greater than the absolute value of the focal length of the other lenses.

[0135] An optical imaging system according to a first exemplary embodiment will be described with reference to Figure 1 and Figure 2 An optical imaging system according to a first exemplary embodiment will be described with reference to

[0136] The optical imaging system 100 in the first exemplary embodiment can include an optical system including a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, and a seventh lens 170, and can further include a filter 180 and an image sensor IS.

[0137] The optical imaging system 100 in the first exemplary embodiment can form a focal point on an imaging surface 190. The imaging surface 190 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 190 can refer to one surface of the image sensor IS on which light is received.

[0138] The lens properties (radius of curvature, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 1.

[0139] Table 1

[0140]

[0141]

[0142] The total focal length f of the optical imaging system 100 in the first exemplary embodiment is 5.4292 mm, f345 is -38.2 mm, ImgHT is 5.107 mm, SWG31_0.2 is -0.5°, SWG31_0.5 is -2.45°, SWG41_0.3 is 0.57°, SWG42_0.2 is 0.5°, and SWG42 is -6.2°.

[0143] In the first exemplary embodiment, the first lens 110 can have a positive refractive power, the first surface of the first lens 110 can be convex, and the second surface of the first lens 110 can be concave.

[0144] The second lens 120 can have a negative refractive power, the first surface of the second lens 120 can be convex, and the second surface of the second lens 120 can be concave.

[0145] The third lens 130 can have a positive refractive power, the first surface of the third lens 130 can be concave, and the second surface of the third lens 130 can be convex.

[0146] The fourth lens 140 can have a negative refractive power, the first surface of the fourth lens 140 can be convex in a paraxial region, and the second surface of the fourth lens 140 can be concave in the paraxial region.

[0147] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fourth lens 140. For example, the first surface of the fourth lens 140 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fourth lens 140 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0148] The fifth lens 150 can have a negative refractive power, the first surface of the fifth lens 150 can be convex, and the second surface of the fifth lens 150 can be concave.

[0149] The sixth lens 160 can have a positive refractive power, the first surface of the sixth lens 160 can be convex in a paraxial region, and the second surface of the sixth lens 160 can be concave in the paraxial region.

[0150] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 160. For example, the first surface of the sixth lens 160 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 160 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0151] The seventh lens 170 can have a negative refractive power, and the first and second surfaces of the seventh lens 170 can be concave in a paraxial region.

[0152] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 170. For example, the first surface of the seventh lens 170 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 170 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0153] Each surface of the first to seventh lenses 110 to 170 can have the aspheric coefficients listed in Table 2. For example, both the object side surface and the image side surface of the first to seventh lenses 110 to 170 can be aspheric.

[0154] Table 2

[0155]

[0156]

[0157]

[0158] The optical imaging system configured as above can have an aberration characteristic as shown in Figure 2 .

[0159] An optical imaging system according to a second exemplary embodiment will be described with reference to Figure 3 and Figure 4 .

[0160] The optical imaging system 200 in the second exemplary embodiment can include an optical system including a first lens 210, a second lens 220, a third lens 230, a fourth lens 240, a fifth lens 250, a sixth lens 260, and a seventh lens 270, and can further include a filter 280 and an image sensor IS.

[0161] The optical imaging system 200 in the second exemplary embodiment can form a focal point on an imaging surface 290. The imaging surface 290 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 290 can refer to one surface of the image sensor IS on which light is received.

[0162] The lens properties (curvature radius, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 3.

[0163] Table 3

[0164]

[0165]

[0166] The total focal length f of the optical imaging system 200 in the second exemplary embodiment is 5.4006 mm, f345 is -51.398 mm, ImgHT is 5.107 mm, SWG31_0.2 is 0.48°, SWG31_0.5 is 0.29°, SWG41_0.3 is 0.7°, SWG42_0.2 is 0.52°, and SWG42 is -9.2°.

[0167] In the second exemplary embodiment, the first lens 210 can have a positive refractive power, the first surface of the first lens 210 can be convex, and the second surface of the first lens 210 can be concave.

[0168] The second lens 220 can have a negative refractive power, the first surface of the second lens 220 can be convex, and the second surface of the second lens 220 can be concave.

[0169] The third lens 230 can have a positive refractive power, the first surface of the third lens 230 can be convex, and the second surface of the third lens 230 can be concave.

[0170] The fourth lens 240 can have a negative refractive power, the first surface of the fourth lens 240 can be convex in a paraxial region, and the second surface of the fourth lens 240 can be concave in the paraxial region.

[0171] The fifth lens 250 can have a negative refractive power, the first surface of the fifth lens 250 can be convex, and the second surface of the fifth lens 250 can be concave.

[0172] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 250. For example, the first surface of the fifth lens 250 can be convex in a paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fifth lens 250 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0173] The sixth lens 260 can have a positive refractive power, the first surface of the sixth lens 260 can be convex in a paraxial region, and the second surface of the sixth lens 260 can be concave in the paraxial region.

[0174] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 260. For example, the first surface of the sixth lens 260 can be convex in a paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 260 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0175] The seventh lens 270 can have a negative refractive power, and the first and second surfaces of the seventh lens 270 can be concave in the paraxial region.

[0176] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 270. For example, the first surface of the seventh lens 270 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 270 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0177] Each surface of the first to seventh lenses 210 to 270 can have the aspheric coefficients listed in Table 4. For example, both the object side surface and the image side surface of the first to seventh lenses 210 to 270 can be aspheric.

[0178] Table 4

[0179]

[0180]

[0181]

[0182] The optical imaging system configured as above can have an aberration characteristic as shown in Figure 4 .

[0183] An optical imaging system according to a third exemplary embodiment will be described with reference to Figure 5 and Figure 6 .

[0184] The optical imaging system 300 in the third exemplary embodiment can include an optical system including a first lens 310, a second lens 320, a third lens 330, a fourth lens 340, a fifth lens 350, a sixth lens 360, and a seventh lens 370, and can further include a filter 380 and an image sensor IS.

[0185] The optical imaging system 300 in the third exemplary embodiment can form a focal point on an imaging surface 390. The imaging surface 390 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 390 can refer to one surface of the image sensor IS on which light is received.

[0186] The lens properties (curvature radius, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 5.

[0187] Table 5

[0188]

[0189]

[0190] The total focal length f of the optical imaging system 300 in the third exemplary embodiment is 5.4291 mm, f345 is -31.316 mm, ImgHT is 5.107 mm, SWG31_0.2 is -0.6°, SWG31_0.5 is -2.9°, SWG41_0.3 is 0.55°, SWG42_0.2 is 0.47°, and SWG42 is -2.9°.

[0191] In the third exemplary embodiment, the first lens 310 can have a positive refractive power, the first surface of the first lens 310 can be convex, and the second surface of the first lens 310 can be concave.

[0192] The second lens 320 can have a negative refractive power, the first surface of the second lens 320 can be convex, and the second surface of the second lens 320 can be concave.

[0193] The third lens 330 can have a positive refractive power, the first surface of the third lens 330 can be convex, and the second surface of the third lens 330 can be concave.

[0194] The fourth lens 340 can have a negative refractive power, the first surface of the fourth lens 340 can be convex, and the second surface of the fourth lens 340 can be concave.

[0195] The fifth lens 350 can have a negative refractive power, the first surface of the fifth lens 350 can be convex in the paraxial region, and the second surface of the fifth lens 350 can be concave in the paraxial region.

[0196] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 350. For example, the first surface of the fifth lens 350 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fifth lens 350 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0197] The sixth lens 360 can have a positive refractive power, the first surface of the sixth lens 360 can be convex in the paraxial region, and the second surface of the sixth lens 360 can be concave in the paraxial region.

[0198] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 360. For example, the first surface of the sixth lens 360 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 360 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0199] The seventh lens 370 can have a negative refractive power, and the first and second surfaces of the seventh lens 370 can be concave in the paraxial region.

[0200] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 370. For example, the first surface of the seventh lens 370 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 370 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0201] Each surface of the first to seventh lenses 310 to 370 can have the aspherical coefficients listed in Table 6. For example, both the object side surface and the image side surface of the first to seventh lenses 310 to 370 can be aspherical.

[0202] Table 6

[0203]

[0204]

[0205]

[0206] The optical imaging system configured as above can have an aberration characteristic as shown in FIG. 17. Figure 6

[0207] An optical imaging system according to a fourth exemplary embodiment will be described with reference to Figure 7 and Figure 8 An optical imaging system according to a fourth exemplary embodiment will be described with reference to

[0208] The optical imaging system 400 in the fourth exemplary embodiment can include an optical system including a first lens 410, a second lens 420, a third lens 430, a fourth lens 440, a fifth lens 450, a sixth lens 460, and a seventh lens 470, and can further include a filter 480 and an image sensor IS.

[0209] ​The optical imaging system 400 in the fourth exemplary embodiment can form a focal point on an imaging surface 490. The imaging surface 490 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 490 can refer to one surface of the image sensor IS on which light is received.

[0210] The lens properties (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 7.

[0211] Table 7

[0212] Face Number Label Radius of Curvature Thickness or Distance Refractive Index Abbe Number Focal Length S1 First Lens 1.99 0.826 1.544 56.1 4.5489 S2 8.50 0.080 S3 Second Lens 16.56 0.274 1.671 19.4 -12.6 S4 5.60 0.358 S5 Third Lens -27.66 0.341 1.567 38.0 46.878 S6 -13.66 0.102 S7 Fourth Lens 21.24 0.250 1.671 19.4 -118.937 S8 16.73 0.559 S9 Fifth Lens 14.18 0.300 1.567 38.0 -28.748 S10 7.55 0.343 S11 Sixth Lens 2.81 0.478 1.544 56.1 6.1037 S12 16.87 0.628 S13 Seventh Lens -75.54 0.490 1.535 56.1 -4.1 S14 2.27 0.210 S15 Filter Infinity 0.110 1.518 64.2 S16 Infinity 0.740 S17 Imaging Surface Infinity

[0213] The total focal length f of the optical imaging system 400 in the fourth exemplary embodiment is 5.4292 mm, f345 is -47.745 mm, ImgHT is 5.107 mm, SWG31_0.2 is -0.55°, SWG31_0.5 is -2.46°, SWG41_0.3 is 0.3°, SWG42_0.2 is 0.07°, and SWG42 is -3°.

[0214] In the fourth exemplary embodiment, the first lens 410 can have a positive refractive power, the first surface of the first lens 410 can be convex, and the second surface of the first lens 410 can be concave.

[0215] The second lens 420 can have a negative refractive power, the first surface of the second lens 420 can be convex, and the second surface of the second lens 420 can be concave.

[0216] The third lens 430 can have a positive refractive power, the first surface of the third lens 430 can be concave, and the second surface of the third lens 430 can be convex.

[0217] The fourth lens 440 can have a negative refractive power, the first surface of the fourth lens 440 can be convex in the paraxial region, and the second surface of the fourth lens 440 can be concave in the paraxial region.

[0218] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fourth lens 440. For example, the first surface of the fourth lens 440 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fourth lens 440 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0219] The fifth lens 450 can have a negative refractive power, the first surface of the fifth lens 450 can be convex, and the second surface of the fifth lens 450 can be concave.

[0220] The sixth lens 460 can have a positive refractive power, the first surface of the sixth lens 460 can be convex in the paraxial region, and the second surface of the sixth lens 460 can be concave in the paraxial region.

[0221] 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 460. For example, the first surface of the sixth lens 460 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 460 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0222] The seventh lens 470 can have a negative refractive power, and the first surface and the second surface of the seventh lens 470 can be concave in the paraxial region.

[0223] 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 470. For example, the first surface of the seventh lens 470 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 470 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0224] Each surface of the first lens 410 to the seventh lens 470 can have the aspheric coefficients listed in Table 8. For example, both the object side surface and the image side surface of the first lens 410 to the seventh lens 470 can be aspheric.

[0225] Table 8

[0226]

[0227]

[0228] The optical imaging system configured as above can have an aberration characteristic as shown in Figure 8 .

[0229] An optical imaging system according to a fifth exemplary embodiment will be described with reference to Figure 9 and Figure 10 .

[0230] The optical imaging system 500 in the fifth exemplary embodiment can include an optical system including a first lens 510, a second lens 520, a third lens 530, a fourth lens 540, a fifth lens 550, a sixth lens 560, and a seventh lens 570, and can further include a filter 580 and an image sensor IS.

[0231] The optical imaging system 500 in the fifth exemplary embodiment can form a focal point on an imaging surface 590. The imaging surface 590 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 590 can refer to one surface of the image sensor IS on which light is received.

[0232] The lens properties (radius of curvature, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 9.

[0233] Table 9

[0234] Face Number Label Radius of Curvature Thickness or Distance Refractive Index Abbe Number Focal Length S1 First Lens 2.73 1.048 1.544 56.1 6.26 S2 11.78 0.116 S3 Second Lens 12.55 0.280 1.671 19.4 -17.15 S4 5.98 0.466 S5 Third Lens -229.22 0.395 1.535 56.1 41.26 S6 -20.20 0.172 S7 Fourth Lens 34.97 0.388 1.671 19.4 -57.88 S8 18.39 0.712 S9 Fifth Lens 31.10 0.479 1.567 38.0 -36.776 S10 12.45 0.380 S11 Sixth Lens 2.90 0.670 1.544 56.1 6.208 S12 18.39 1.011 S13 Seventh Lens -34.08 0.490 1.535 56.1 -4.883 S14 2.85 0.520 S15 Filter Infinity 0.210 1.518 64.2 S16 Infinity 0.493 S17 Imaging Surface Infinity

[0235] The total focal length f of the optical imaging system 500 in the fifth exemplary embodiment is 6.5 mm, f345 is -52.222 mm, ImgHT is 6 mm, SWG31_0.2 is -0.15°, SWG31_0.5 is -1.52°, SWG41_0.3 is 0.5°, SWG42_0.2 is -0.19°, and SWG42 is -8.2°.

[0236] In the fifth exemplary embodiment, the first lens 510 can have a positive refractive power, the first surface of the first lens 510 can be convex, and the second surface of the first lens 510 can be concave.

[0237] The second lens 520 can have a negative refractive power, the first surface of the second lens 520 can be convex, and the second surface of the second lens 520 can be concave.

[0238] The third lens 530 can have a positive refractive power, the first surface of the third lens 530 can be concave, and the second surface of the third lens 530 can be convex.

[0239] The fourth lens 540 can have a negative refractive power, the first surface of the fourth lens 540 can be convex, and the second surface of the fourth lens 540 can be concave.

[0240] The fifth lens 550 can have a negative refractive power, the first surface of the fifth lens 550 can be convex, and the second surface of the fifth lens 550 can be concave.

[0241] The sixth lens 560 can have a positive refractive power, the first surface of the sixth lens 560 can be convex in a paraxial region, and the second surface of the sixth lens 560 can be concave in the paraxial region.

[0242] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 560. For example, the first surface of the sixth lens 560 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 560 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0243] The seventh lens 570 can have a negative refractive power, and the first and second surfaces of the seventh lens 570 can be concave in the paraxial region.

[0244] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 570. For example, the first surface of the seventh lens 570 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 570 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0245] Each surface of the first to seventh lenses 510 to 570 can have the aspheric coefficients listed in Table 10. For example, both the object side surface and the image side surface of the first to seventh lenses 510 to 570 can be aspheric.

[0246] Table 10

[0247]

[0248]

[0249]

[0250] The optical imaging system configured as above can have an aberration characteristic as shown in Figure 10 .

[0251] An optical imaging system according to a sixth exemplary embodiment will be described with reference to Figure 11 and Figure 12 .

[0252] The optical imaging system 600 in the sixth exemplary embodiment can include an optical system including a first lens 610, a second lens 620, a third lens 630, a fourth lens 640, a fifth lens 650, a sixth lens 660, and a seventh lens 670, and can further include a filter 680 and an image sensor IS.

[0253] The optical imaging system 600 in the sixth exemplary embodiment can form a focal point on an imaging surface 690. The imaging surface 690 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 690 can refer to one surface of the image sensor IS on which light is received.

[0254] The lens properties (radius of curvature, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 11.

[0255] Table 11

[0256]

[0257]

[0258] The total focal length f of the optical imaging system 600 in the sixth exemplary embodiment is 5.16 mm, f345 is -23.478 mm, ImgHT is 4.813 mm, SWG31_0.2 is -0.58°, SWG31_0.5 is -2.8°, SWG41_0.3 is 0.68°, SWG42_0.2 is 0.15°, and SWG42 is -2.9°.

[0259] In the sixth exemplary embodiment, the first lens 610 can have a positive refractive power, the first surface of the first lens 610 can be convex, and the second surface of the first lens 610 can be concave.

[0260] The second lens 620 can have a negative refractive power, the first surface of the second lens 620 can be convex, and the second surface of the second lens 620 can be concave.

[0261] The third lens 630 can have a positive refractive power, the first surface of the third lens 630 can be concave, and the second surface of the third lens 630 can be convex.

[0262] The fourth lens 640 can have a negative refractive power, the first surface of the fourth lens 640 can be convex, and the second surface of the fourth lens 640 can be concave.

[0263] The fifth lens 650 can have a negative refractive power, the first surface of the fifth lens 650 can be convex in the paraxial region, and the second surface of the fifth lens 650 can be concave in the paraxial region.

[0264] 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 first surface of the fifth lens 650 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fifth lens 650 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0265] The sixth lens 660 can have a positive refractive power, the first surface of the sixth lens 660 can be convex in the paraxial region, and the second surface of the sixth lens 660 can be concave in the paraxial region.

[0266] 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 can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 660 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0267] The seventh lens 670 can have a negative refractive power, and the first and second surfaces of the seventh lens 670 can be concave in the paraxial region.

[0268] 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 first surface of the seventh lens 670 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 670 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0269] Each surface of the first to seventh lenses 610 to 670 can have the aspherical coefficients listed in Table 12. For example, both the object side surface and the image side surface of the first to seventh lenses 610 to 670 can be aspherical.

[0270] Table 12

[0271]

[0272]

[0273]

[0274] The optical imaging system configured as above can have an aberration characteristic as shown in Figure 12 .

[0275] Reference will be made to Figure 13 and Figure 14An optical imaging system according to a seventh exemplary embodiment is described.

[0276] The optical imaging system 700 in the seventh exemplary embodiment can include an optical system including a first lens 710, a second lens 720, a third lens 730, a fourth lens 740, a fifth lens 750, a sixth lens 760, and a seventh lens 770, and can further include a filter 780 and an image sensor IS.

[0277] The optical imaging system 700 in the seventh exemplary embodiment can form a focal point on an imaging surface 790. The imaging surface 790 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 790 can refer to one surface of the image sensor IS on which light is received.

[0278] The lens properties (radius of curvature, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 13.

[0279] Table 13

[0280]

[0281]

[0282] The total focal length f of the optical imaging system 700 in the seventh exemplary embodiment is 5.4292 mm, f345 is -41.373 mm, ImgHT is 5.107 mm, SWG31_0.2 is -0.55°, SWG31_0.5 is -2.5°, SWG41_0.3 is 0.55°, SWG42_0.2 is 0.23°, and SWG42 is -3°.

[0283] In the seventh exemplary embodiment, the first lens 710 can have a positive refractive power, the first surface of the first lens 710 can be convex, and the second surface of the first lens 710 can be concave.

[0284] The second lens 720 can have a negative refractive power, the first surface of the second lens 720 can be convex, and the second surface of the second lens 720 can be concave.

[0285] The third lens 730 can have a positive refractive power, the first surface of the third lens 730 can be concave, and the second surface of the third lens 730 can be convex.

[0286] The fourth lens 740 can have a negative refractive power, the first surface of the fourth lens 740 can be convex, and the second surface of the fourth lens 740 can be concave.

[0287] The fifth lens 750 can have a negative refractive power, the first surface of the fifth lens 750 can be convex in the paraxial region, and the second surface of the fifth lens 750 can be concave in the paraxial region.

[0288] 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 first surface of the fifth lens 750 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fifth lens 750 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0289] The sixth lens 760 can have a positive refractive power, the first surface of the sixth lens 760 can be convex in the paraxial region, and the second surface of the sixth lens 760 can be concave in the paraxial region.

[0290] 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 760. For example, the first surface of the sixth lens 760 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 760 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0291] The seventh lens 770 can have a negative refractive power, and the first surface and the second surface of the seventh lens 770 can be concave in the paraxial region.

[0292] 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 770. For example, the first surface of the seventh lens 770 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 770 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0293] Each surface of the first lens 710 to the seventh lens 770 can have the aspheric coefficients listed in Table 14. For example, both the object side surface and the image side surface of the first lens 710 to the seventh lens 770 can be aspheric.

[0294] Table 14

[0295]

[0296]

[0297]

[0298] An optical imaging system configured as above can have an aberration characteristic as shown in Figure 14

[0299] An optical imaging system according to an eighth exemplary embodiment will be described with reference to Figure 15 and Figure 16

[0300] The optical imaging system 800 in the eighth exemplary embodiment can include an optical system including a first lens 810, a second lens 820, a third lens 830, a fourth lens 840, a fifth lens 850, a sixth lens 860, and a seventh lens 870, and can further include a filter 880 and an image sensor IS.

[0301] The optical imaging system 800 in the eighth exemplary embodiment can form a focal point on an imaging surface 890. The imaging surface 890 can refer to a surface on which a focal point is formed by the optical imaging system. For example, the imaging surface 890 can refer to one surface of the image sensor IS on which light is received.

[0302] The lens properties (radius of curvature, thickness of a lens or distance between lenses, refractive index, Abbe number, and focal length) of each lens are listed in Table 15.

[0303] Table 15

[0304]

[0305]

[0306] The total focal length f of the optical imaging system 800 in the eighth exemplary embodiment is 5.4437 mm, f345 is -118.694 mm, ImgHT is 5.107 mm, SWG31_0.2 is 1.7°, SWG31_0.5 is 3°, SWG41_0.3 is 1.06°, SWG42_0.2 is 0.5°, and SWG42 is -14°.

[0307] In the eighth exemplary embodiment, the first lens 810 can have a positive refractive power, the first surface of the first lens 810 can be convex, and the second surface of the first lens 810 can be concave.

[0308] The second lens 820 can have a negative refractive power, and the first and second surfaces of the second lens 820 can be concave.

[0309] The third lens 830 can have a positive refractive power, the first surface of the third lens 830 can be convex, and the second surface of the third lens 830 can be concave.

[0310] ​​The fourth lens 840 can have a negative refractive power, the first surface of the fourth lens 840 can be convex, and the second surface of the fourth lens 840 can be concave.

[0311] The fifth lens 850 can have a negative refractive power, the first surface of the fifth lens 850 can be convex in the paraxial region, and the second surface of the fifth lens 850 can be concave in the paraxial region.

[0312] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the fifth lens 850. For example, the first surface of the fifth lens 850 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the fifth lens 850 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0313] The sixth lens 860 can have a positive refractive power, the first surface of the sixth lens 860 can be convex in the paraxial region, and the second surface of the sixth lens 860 can be concave in the paraxial region.

[0314] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the sixth lens 860. For example, the first surface of the sixth lens 860 can be convex in the paraxial region, and can be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 860 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0315] The seventh lens 870 can have a negative refractive power, and the first and second surfaces of the seventh lens 870 can be concave in the paraxial region.

[0316] Further, at least one inflection point can be formed on at least one of the first and second surfaces of the seventh lens 870. For example, the first surface of the seventh lens 870 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region. Further, the second surface of the seventh lens 870 can be concave in the paraxial region, and can be convex in a portion other than the paraxial region.

[0317] Each surface of the first to seventh lenses 810 to 870 can have aspheric coefficients listed in Table 16. For example, both the object side surface and the image side surface of the first to seventh lenses 810 to 870 can be aspheric.

[0318] Table 16

[0319]

[0320]

[0321]

[0322] An optical imaging system configured as above can have an aberration characteristic as shown in Figure 16 .

[0323] According to the above exemplary embodiments, the optical imaging system can achieve high resolution and can have a reduced size.

[0324] While specific example embodiments have been shown and described above, it will be apparent to those having ordinary skill in the art, upon understanding the disclosure, that various changes in form and details can be made without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered merely illustrative, and not restrictive, in nature. Descriptions of features or aspects within each example are considered to apply to similar features or aspects within other examples. Suitable results can also be obtained if the described techniques are performed in a different order, and / or if the components of the described systems, architectures, devices, or circuits are combined in different manners, and / or replaced or supplemented by other components or their equivalents. Accordingly, the scope of the disclosure is not limited to the specific embodiments described herein, but only by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.

Claims

1. An optical imaging system comprising: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens disposed in order from an object side, and an image sensor for converting light passing through the first lens to the seventh lens into an electric signal, wherein the first lens has a positive refractive power, a convex object side surface, and a concave image side surface, the second lens has a negative refractive power, a convex object side surface, and a concave image side surface, the third lens has a positive refractive power, a concave object side surface, and a convex image side surface, the fourth lens has a negative refractive power, a convex object side surface, and a concave image side surface, the fifth lens has a negative refractive power, a convex object side surface, and a concave image side surface, the sixth lens has a positive refractive power, a convex object side surface, and a concave image side surface, and the seventh lens has a negative refractive power, a concave object side surface, and a concave image side surface, wherein the number of lenses having a refractive power in the optical imaging system is seven, wherein 11.52 / -28.786 ≤ R8 / f4 < 0 is satisfied, wherein R8 is a radius of curvature of an image side surface of the fourth lens, and f4 is a focal length of the fourth lens, wherein 0.5 < TTL / (2×ImgHT) < 0.67 is satisfied, wherein TTL is a distance on an optical axis from an object side surface of the first lens to an image plane, and ImgHT is half of a diagonal length of the image plane, wherein -0.2 < f / f4 ≤ 6.5 / -57.88 is satisfied, wherein f is a total focal length of the optical imaging system, and wherein (1.223 / 6.5) ≤ BFL / f ≤ (1.06 / 5.16) is satisfied, wherein BFL is a distance on the optical axis from an image side surface of the seventh lens to the image plane.

2. The optical imaging system of claim 1, wherein, 4.5 mm < ImgHT < 6.5 mm is satisfied.

3. The optical imaging system of claim 1, wherein, TTL / ∑CT < 2.97 is satisfied, wherein ∑CT is a sum of thicknesses of the first lens to the seventh lens on the optical axis.

4. The optical imaging system of claim 1, wherein, v1-v2 < 38 and n2 + n4 > 3.3 are satisfied, wherein v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, n2 is a refractive index of the second lens, and n4 is a refractive index of the fourth lens.

5. The optical imaging system of claim 1, wherein, TTL / f < 1.205 is satisfied.

6. The optical imaging system of claim 1, wherein, -0.02 < CT4 / f4 < 0 is satisfied, wherein CT4 is a thickness of the fourth lens on the optical axis.

7. The optical imaging system of claim 1, wherein, -20° < SWG42 ≤ -2.9° is satisfied, wherein SWG42 is a grazing angle at a point of a maximum effective diameter of an image side surface of the fourth lens.

8. The optical imaging system of claim 1, wherein, 0° < SWG41_0.3 < 1.1° is satisfied, wherein SWG41_0.3 is a grazing angle at a point of a maximum effective diameter × 0.3 of an object side surface of the fourth lens.

9. The optical imaging system of claim 1, wherein, -0.5° < SWG42_0.2 < 0.6° is satisfied, wherein SWG42_0.2 is a grazing angle at a point of a maximum effective diameter × 0.2 of an image side surface of the fourth lens.

10. The optical imaging system of claim 1, wherein, -3° < SWG31_0.5 < 3°, where SWG31_0.5 is a grazing angle at a point of 0.5 times a maximum effective diameter of an object side surface of the third lens.

11. The optical imaging system of claim 1, wherein, -1° < SWG31_0.2 < 2°, where SWG31_0.2 is a grazing angle at a point of 0.2 times a maximum effective diameter of an object side surface of the third lens.

12. The optical imaging system of claim 1, wherein, 0.3 < |f1 / f2| < 0.45 is satisfied, where f1 is a focal length of the first lens, and f2 is a focal length of the second lens.

13. The optical imaging system of claim 1, wherein, 20 mm < |f345| < 120 mm and 4 < |f345| / f < 25 are satisfied, where f345 is a combined focal length of the third lens to the fifth lens.

14. An optical imaging system comprising: a first lens having positive refractive power, a convex object side surface, and a concave image side surface; a second lens having negative refractive power, a convex object side surface, and a concave image side surface; a third lens having positive refractive power, a concave object side surface, and a convex image side surface; a fourth lens having negative refractive power, a convex object side surface, and a concave image side surface; a fifth lens having negative refractive power, a convex object side surface, and a concave image side surface; a sixth lens having positive refractive power, a convex object side surface, and a concave image side surface; a seventh lens having negative refractive power, a concave object side surface, and a concave image side surface; and an image sensor for converting light that has passed through the first lens to the seventh lens into an electrical signal, wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are disposed in this order from an object side, wherein the number of lenses having refractive power in the optical imaging system is seven, wherein -0.2 < f / f4 < 6.5 / -57.88 is satisfied, where f is a total focal length of the optical imaging system, and f4 is a focal length of the fourth lens, wherein 11.52 / -28.786 < R8 / f4 < 0 is satisfied, where R8 is a radius of curvature of an image side surface of the fourth lens, and wherein (1.223 / 6.5) < BFL / f < (1.06 / 5.16) is satisfied, where BFL is a distance on the optical axis from an image side surface of the seventh lens to the imaging surface. TTL / ∑CT < 2.97 is satisfied, where ∑CT is a sum of thicknesses on the optical axis of the first lens to the seventh lens, and TTL is a distance on the optical axis from an object side surface of the first lens to the imaging surface.

15. The optical imaging system of claim 14, wherein, 16. An optical imaging system comprising: a first lens having positive refractive power, a convex object side surface, and a concave image side surface; a second lens having negative refractive power, a convex object side surface, and a concave image side surface; a third lens having positive refractive power, a concave object side surface, and a convex image side surface; a fourth lens having negative refractive power, a convex object side surface, and a concave image side surface; a fifth lens having negative refractive power, a convex object side surface, and a concave image side surface; ​ a sixth lens having positive refractive power, a convex object side surface, and a concave image side surface; a seventh lens having negative refractive power, a concave object side surface, and a concave image side surface; and an image sensor configured to convert light passing through the first lens to the seventh lens into an electrical signal, wherein the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are arranged in this order from an object side, wherein the number of lenses having refractive power in the optical imaging system is seven, and wherein v1-v2 < 38 and n2+n4 > 3.3 are satisfied, where v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, n2 is the refractive index of the second lens, and n4 is the refractive index of the fourth lens, wherein 11.52 / -28.786 ≤ R8 / f4 < 0 is satisfied, where R8 is the radius of curvature of the image side surface of the fourth lens, and f4 is the focal length of the fourth lens, wherein -0.2 < f / f4 ≤ 6.5 / -57.88 is satisfied, where f is the total focal length of the optical imaging system, and wherein (1.223 / 6.5) ≤ BFL / f ≤ (1.06 / 5.16) is satisfied, where BFL is the distance on the optical axis from the image side surface of the seventh lens to the image plane.

Images