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, a seventh lens, an eighth lens, and a ninth lens, wherein the first lens has a positive refractive power, the second lens has a negative refractive power and a refractive index higher than 1.6, either of the third lens and the fourth lens has a refractive index higher than 1.6, the sixth lens has a negative refractive power and a refractive index higher than 1.6, and TTL / (2*IMG_HT) < 0.61, wherein TTL is a distance on an optical axis from an object side surface of the first lens to an imaging surface, and IMG_HT is half of a diagonal length of the imaging surface.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2020-0164581, filed with the Korean Intellectual Property Office on November 30, 2020, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] This disclosure relates to optical imaging systems. Background Technology

[0004] Recently, mobile terminals have been equipped with camera modules, which include optical imaging systems with multiple lenses to enable video calls and image capture.

[0005] In addition, as the functionality of camera modules in mobile terminals gradually increases, camera modules used in mobile terminals are increasingly required to have higher resolutions than previous camera modules.

[0006] Furthermore, mobile devices have become increasingly smaller, thus requiring camera modules used in mobile devices to be thin.

[0007] Therefore, there is a need to develop a thin optical imaging system that can achieve high resolution.

[0008] The above information is presented as background information only to aid in understanding this disclosure. No determination or assertion is made as to whether any of the above content can be used as prior art in relation 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 one general aspect, an optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens arranged sequentially from the object side, wherein the first lens has positive refractive power, the second lens has negative refractive power and a refractive index greater than 1.6, either the third or fourth lens has a refractive index greater than 1.6, the sixth lens has negative refractive power and a refractive index greater than 1.6, and TTL / (2×IMGHT)<0.61, where TTL is the distance on the optical axis from the object side of the first lens to the imaging plane, and IMGHT is half the diagonal length of the imaging plane.

[0011] TTL / ∑CT can be less than 2, where ∑CT is the sum of the thicknesses of the first to ninth lenses along the optical axis.

[0012] f / f1 can be greater than 0.6 and less than 1.5, where f is the total focal length of the optical imaging system and f1 is the focal length of the first lens.

[0013] v1-v2 can be greater than 30, where v1 is the Abbe number of the first lens and v2 is the Abbe number of the second lens.

[0014] TTL / f can be greater than 1 and less than 1.25.

[0015] n2+n3 can be greater than 3.15, where n2 is the refractive index of the second lens and n3 is the refractive index of the third lens.

[0016] BFL / f can be greater than 0.15 and less than 0.25, where BFL is the distance on the optical axis from the image side of the ninth lens to the imaging plane.

[0017] D1 / f can be greater than 0.001 and less than 0.04, where D1 is the distance on the optical axis between the image-side surface of the first lens and the object-side surface of the second lens.

[0018] R1 / f can be greater than 0.3 and less than 0.4, where R1 is the radius of curvature of the object side surface of the first lens.

[0019] Fno can be less than 2.3, where Fno is the f-number of the optical imaging system.

[0020] f1 / |f2| can be less than 0.34, where f2 is the focal length of the second lens.

[0021] The third lens can have positive refractive power.

[0022] The fourth and fifth lenses may have refractive powers with opposite signs, the seventh and eighth lenses may each have positive refractive powers, and the ninth lens may have negative refractive powers.

[0023] The third and ninth lenses can each have negative refractive power, and the fourth, fifth, seventh, and eighth lenses can each have positive refractive power.

[0024] In another general aspect, an optical imaging system includes: a first lens having a positive refractive power, a convex object side, and a concave image side; a second lens having a negative refractive power, a convex object side, and a concave image side; a third lens having a refractive power, a convex object side, and a concave image side; a fourth lens and a fifth lens each having a refractive power; a sixth lens having a negative refractive power; a seventh lens and an eighth lens each having a positive refractive power; and a ninth lens having a negative refractive power, wherein the first lens to the ninth lens are arranged in order from the object side, and wherein, TTL / ∑CT < 2, where TTL is the distance on the optical axis from the object side of the first lens to the imaging surface, and ∑CT is the sum of the thicknesses of the first lens to the ninth lens on the optical axis.

[0025] TTL / (2×IMG HT) can be less than 0.61, where IMG HT is half of the diagonal length of the imaging surface.

[0026] The seventh lens and the eighth lens can each have a convex object side and a concave image side, and the ninth lens can have a concave object side and a concave image side.

[0027] Either one of the third lens and the fourth lens, the second lens, and the sixth lens can each have a refractive index higher than 1.6.

[0028] In another general aspect, an optical imaging system includes: a first lens having a positive refractive power; a second lens having a refractive power; a third lens having a refractive power, a convex object side, and a concave image side; a fourth lens and a fifth lens each having a refractive power; a sixth lens having a negative refractive power; a seventh lens and an eighth lens each having a positive refractive power, a convex object side, and a concave image side; and a ninth lens having a negative refractive power, a concave object side, and a concave image side, wherein the first lens to the ninth lens are arranged in order from the object side, and wherein, 0.6 < f / f1 < 1.5, where f is the total focal length of the optical imaging system, and f1 is the focal length of the first lens.

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

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

[0031] Figure 2 presents having a representation Figure 1 a graph with curves showing the aberration characteristics of the optical imaging system shown in.

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

[0033] Figure 4 Presented with representation Figure 3 The graph shows the aberration characteristics of the optical imaging system.

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

[0035] Figure 6 It shows a representation Figure 5 The graph shows the aberration characteristics of the optical imaging system.

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

[0037] Figure 8 Presented with representation Figure 7 The graph shows the aberration characteristics of the optical imaging system.

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

[0039] Figure 10 Presented with representation Figure 9 The graph shows the aberration characteristics of the optical imaging system.

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

[0041] Figure 12 Presented with representation Figure 11 The graph shows the aberration characteristics of the optical imaging system.

[0042] Throughout the accompanying drawings and detailed embodiments, the same reference numerals refer to the same elements. For purposes of clarity, illustration, and convenience, the drawings may not be drawn to scale, and the relative dimensions, scale, and depiction of elements in the drawings may be exaggerated. Detailed Implementation

[0043] In the following, although exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the exemplary embodiments are not limited thereto.

[0044] The following detailed embodiments are provided to help readers gain a comprehensive understanding of the methods, apparatus, and / or systems described in this application. However, after understanding this disclosure, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described in this application will be apparent. For example, the order of operations described in this application is merely illustrative, and is not limited to the order set forth in this application, except for operations that must occur in a specific order, but can be obviously changed after understanding this disclosure. In addition, for clarity and conciseness, descriptions of functions and structures well-known in the art may be omitted.

[0045] The features described in this application may be implemented in different forms and should not be construed as being limited to the examples described in this application. Rather, the examples described in this application are provided merely to illustrate some of the many feasible ways of implementing the methods, apparatus, and / or systems described in this application, which will be apparent upon understanding this disclosure.

[0046] It should be noted that in this application, the term "may" is used in relation to examples or implementations, for example, regarding what an example or implementation may include or implement, meaning that there exists at least one example or implementation that includes or implements such a feature, and that all examples and implementations are not limited thereto.

[0047] Throughout this specification, when an element such as a layer, region, or substrate is described as being "on," "connected to," or "attached to" another element, the element may be directly "on," directly "connected to," or directly "attached to" the other element, or there may be one or more other elements between the element and the other element. Conversely, when an element is described as being "directly on," "directly connected to," or "directly attached to" another element, there are no other elements between the element and the other element. As used herein, a "part" of an element may include the entire element or a portion of the entire element smaller than the entire element.

[0048] As used in this application, the term “and / or” includes any one of the associated listed items and any combination of any two or more items; similarly, “at least one of…” includes any one of the associated listed items and any combination of any two or more items.

[0049] Although terms such as “first,” “second,” and “third” may be used in this application to describe various components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teachings of the examples described in this application, the first component, first assembly, first region, first layer, or first part mentioned in these examples may also be referred to as a second component, second assembly, second region, second layer, or second part.

[0050] Spatial relative terms such as “above,” “above,” “below,” and “below” may be used in this application for descriptive convenience to describe the relationship of one element relative to another, as shown in the accompanying drawings. In addition to covering the orientation depicted in the drawings, these spatial relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “above” another element would be located “below” or “below” that other element. Thus, depending on the spatial orientation of the device, the term “above” covers both orientations of “above” and “below”. The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative terms used in this application should be interpreted accordingly.

[0051] The terminology used in this application is for describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the articles “a,” “an,” and “the” are intended to include plural forms as well. The terms “comprising,” “including,” and “having” indicate the presence of the stated features, numbers, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, components, elements, and / or combinations thereof.

[0052] Variations in the shapes shown in the accompanying drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described in this application are not limited to the specific shapes shown in the accompanying drawings, but include shape variations that may occur during manufacturing.

[0053] The features of the examples described in this application can be combined in various ways that will become apparent upon understanding this disclosure. Furthermore, although the examples described in this application have multiple configurations, other configurations that will become apparent upon understanding this disclosure are also possible.

[0054] In the accompanying drawings, for ease of illustration, the thickness, size, and shape of the lenses have been slightly exaggerated. In particular, the shapes of the spherical or aspherical surfaces shown in the drawings are illustrated by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to those shown in the drawings.

[0055] The first lens can refer to the lens closest to the object side, while the last lens can refer to the lens closest to the image sensor.

[0056] Furthermore, the first surface (or object-side surface) of each lens refers to its surface closest to the object side, and the second surface (or image-side surface) of each lens refers to its surface closest to the image side. In addition, in this specification, all values ​​for the radius of curvature, thickness, distance, etc., of the lens are expressed in millimeters (mm), and the field of view (FOV) is expressed in degrees.

[0057] Furthermore, in the description of the shape of each lens, a lens with one convex surface indicates that the paraxial region of the corresponding surface is convex, a lens with one concave surface indicates that the paraxial region of the corresponding surface is concave, and a lens with one flat surface indicates that the paraxial region of the corresponding surface is flat.

[0058] Therefore, although one surface of the lens is described as convex, the edge portion of the lens may be concave. Similarly, although one surface of the lens is described as concave, the edge portion of the lens may be convex. Furthermore, although one surface of the lens is described as flat, the edge portion of the lens may be either convex or concave.

[0059] The paraxial region of a lens surface is the central part of the lens surface that surrounds and includes the optical axis. Light rays incident on the lens surface in the paraxial region form a small angle θ with the optical axis, and the approximations sinθ≈θ, tanθ≈θ, and cosθ≈1 are valid.

[0060] One aspect of this disclosure is that it can provide an optical imaging system that is both thin and has high resolution.

[0061] An optical imaging system according to an example embodiment of this disclosure may include at least nine lenses.

[0062] For example, an optical imaging system according to an exemplary embodiment may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens arranged in ascending numerical order along the optical axis from the object side of the optical imaging system toward the imaging surface of the optical imaging system. The first to ninth lenses may be arranged to be spaced apart from each other by a predetermined distance along the optical axis.

[0063] The optical imaging system according to the example embodiment may further include an image sensor having an imaging surface disposed at the imaging plane of the optical imaging system. The image sensor converts an image of an object formed by the lens of the optical imaging system on the effective imaging area of ​​the imaging surface into an electrical signal.

[0064] In addition, the optical imaging system may also include an infrared cutoff filter (hereinafter referred to as a "filter") that blocks infrared light. The filter may be positioned between the final lens and the imaging plane.

[0065] Additionally, the optical imaging system may include at least one aperture stop for controlling the amount of light. The at least one aperture stop may be positioned before the first lens, between any two adjacent lenses from the first to the ninth lens, or between the ninth lens and the imaging plane. The optical imaging system may include two or more aperture stops positioned at different locations.

[0066] In an optical imaging system according to an example embodiment of this disclosure, the lens may be formed of a plastic material.

[0067] In addition, all lenses may have aspherical surfaces. For example, each of the first through ninth lenses may have at least one aspherical surface.

[0068] That is, at least one of the first and second surfaces of all lenses from the first to the ninth can be aspherical. Here, the aspherical surfaces of the first to the ninth lenses can be represented by the following Equation 1:

[0069] Equation 1

[0070]

[0071] Here, c is the curvature of the lens (the reciprocal of the radius of curvature), K is the conic constant, and Y is the distance from a point on the aspherical surface of the lens to the optical axis in a direction perpendicular to the optical axis. Additionally, constants A to H, J, and L to P are aspherical coefficients. Furthermore, Z is the distance between a point on the aspherical surface of the lens at a distance Y from the optical axis and the tangent plane intersecting the vertex of the aspherical surface.

[0072] An optical imaging system comprising a first lens to a ninth lens may, from the object side, sequentially possess positive refractive power / negative refractive power / positive refractive power / negative refractive power / positive refractive power / negative refractive power / positive refractive power / negative refractive power / positive refractive power / negative refractive power. Alternatively, an optical imaging system comprising a first lens to a ninth lens may, from the object side, sequentially possess positive refractive power / negative refractive power / positive refractive power / positive refractive power / negative refractive power / positive refractive power / positive refractive power / negative refractive power. Alternatively, an optical imaging system comprising a first lens to a ninth lens may, from the object side, sequentially possess positive refractive power / negative refractive power / positive refractive power / positive refractive power / negative refractive power / positive refractive power / negative refractive power / positive refractive power / negative refractive power.

[0073] An optical imaging system according to an exemplary embodiment of this disclosure can satisfy at least one of the following conditional expressions:

[0074] (Conditional expression 1) TTL / (2×IMG HT)<0.61

[0075] (Conditional expression 2) TTL / ∑CT<2

[0076] (Conditional expression 3) 0.6 <f / f1<1.5

[0077] (Conditional expression 4) v1-v2>30

[0078] (Conditional Expression 5) 1 <TTL / f<1.25

[0079] (Conditional expression 6) n² + n³ > 3.15

[0080] (Conditional expression 7) 0.15 <BFL / f<0.25

[0081] (Conditional expression 8) 0.001 <D1 / f<0.04

[0082] (Conditional expression 9) 0.3 <R1 / f<0.4

[0083] (Conditional expression 10) Fno < 2.3

[0084] (Conditional expression 11)f1 / |f2|<0.34

[0085] Here, f is the total focal length of the optical imaging system, f1 is the focal length of the first lens, and f2 is the focal length of the second lens.

[0086] v1 is the Abbe number of the first lens, and v2 is the Abbe number of the second lens.

[0087] TTL is the distance on the optical axis from the object side of the lens (e.g., the first lens) closest to the object side to the imaging plane, and BFL is the distance on the optical axis from the image side of the lens (e.g., the ninth lens) closest to the image sensor.

[0088] n2 is the refractive index of the second lens, and n3 is the refractive index of the third lens.

[0089] R1 is the radius of curvature of the object side surface of the first lens, D1 is the distance on the optical axis between the image side surface of the first lens and the object side surface of the second lens, and ∑CT is the sum of the center thicknesses (e.g., the thickness on the optical axis) of each lens.

[0090] IMG HT is half the diagonal length of the effective imaging area of ​​the image sensor's imaging surface, which is located at the imaging surface of the optical imaging system, and Fno is the f-number of the optical imaging system.

[0091] An optical imaging system according to an example embodiment may include a first lens through a ninth lens.

[0092] The first lens may have positive refractive power. Additionally, the first lens may have a meniscus shape with a convex object-side surface. Specifically, the first surface of the first lens may be convex, and its second surface may be concave.

[0093] At least one of the first and second surfaces of the first lens can be aspherical. For example, both surfaces of the first lens can be aspherical.

[0094] The second lens can have negative refractive power. Additionally, the second lens can have a meniscus shape with a convex object side. Specifically, the first surface of the second lens can be convex, and its second surface can be concave.

[0095] At least one of the first and second surfaces of the second lens can be aspherical. For example, both surfaces of the second lens can be aspherical.

[0096] The third lens can have positive or negative refractive power. Additionally, the third lens can have a meniscus shape with a convex object side. Specifically, the first surface of the third lens can be convex, and its second surface can be concave.

[0097] At least one of the first and second surfaces of the third lens can be aspherical. For example, both surfaces of the third lens can be aspherical.

[0098] The fourth lens can have either positive or negative refractive power. Furthermore, both surfaces of the fourth lens can be concave. Specifically, the first and second surfaces of the fourth lens can be concave.

[0099] Alternatively, the fourth lens may have a meniscus shape with a convex object side. Specifically, the first surface of the fourth lens may be convex, and its second surface may be concave.

[0100] At least one of the first and second surfaces of the fourth lens may be aspherical. For example, both surfaces of the fourth lens may be aspherical.

[0101] The fifth lens can have either positive or negative refractive power. Additionally, the fifth lens can have a meniscus shape with a convex object side. Specifically, the first surface of the fifth lens can be convex in the paraxial region, and its second surface can be concave in the paraxial region.

[0102] Alternatively, both surfaces of the fifth lens can be convex. Specifically, the first and second surfaces of the fifth lens can be convex in the paraxial region.

[0103] Alternatively, the fifth lens can have a crescent shape that convexes from the side. Specifically, the first surface of the fifth lens can be concave in the paraxial region, and its second surface can be convex in the paraxial region.

[0104] At least one of the first and second surfaces of the fifth lens may be aspherical. For example, both surfaces of the fifth lens may be aspherical.

[0105] At least one inflection point may be formed on at least one of the first and second surfaces of the fifth lens. For example, the first surface of the fifth lens may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the fifth lens may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0106] The sixth lens can have negative refractive power. Additionally, the sixth lens can have a meniscus shape with a convex object side. Specifically, the first surface of the sixth lens can be convex in the paraxial region, and its second surface can be concave in the paraxial region.

[0107] Alternatively, the sixth lens can have a crescent shape that convexes from the side. Specifically, the first surface of the sixth lens can be concave in the paraxial region, and its second surface can be convex in the paraxial region.

[0108] At least one of the first and second surfaces of the sixth lens may be aspherical. For example, both surfaces of the sixth lens may be aspherical.

[0109] At least one inflection point may be formed on at least one of the first and second surfaces of the sixth lens. For example, the first surface of the sixth lens may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the sixth lens may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0110] The seventh lens can have positive refractive power. Additionally, the seventh lens can have a meniscus shape with a convex object side. Specifically, the first surface of the seventh lens can be convex in the paraxial region, and its second surface can be concave in the paraxial region.

[0111] At least one of the first and second surfaces of the seventh lens can be aspherical. For example, both surfaces of the seventh lens can be aspherical.

[0112] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the seventh lens. For example, the first surface of the seventh lens may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0113] The eighth lens can have positive refractive power. Additionally, the eighth lens can have a meniscus shape with a convex object side. Specifically, the first surface of the eighth lens can be convex in the paraxial region, and its second surface can be concave in the paraxial region.

[0114] At least one of the first and second surfaces of the eighth lens may be aspherical. For example, both surfaces of the eighth lens may be aspherical.

[0115] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens. For example, the first surface of the eighth lens may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0116] The ninth lens can have negative refractive power. Furthermore, both surfaces of the ninth lens can be concave. Specifically, the first and second surfaces of the ninth lens can be concave in the paraxial region.

[0117] At least one of the first and second surfaces of the ninth lens may be aspherical. For example, both surfaces of the ninth lens may be aspherical.

[0118] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens. For example, the first surface of the ninth lens may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0119] The first and second lenses can be formed from plastic materials with different optical properties. For example, the refractive index of the second lens can be greater than that of the first lens. For example, the refractive index of the second lens can be greater than 1.6.

[0120] The ratio of the absolute value of the focal length of the first lens to the focal length of the second lens can be less than 0.34.

[0121] At least three of the multiple lenses in an optical imaging system may have a refractive index greater than 1.6.

[0122] At least two of the second to fourth lenses may have a refractive index greater than 1.6. For example, the second lens may have a refractive index greater than 1.6, and either the third or fourth lens may have a refractive index greater than 1.6.

[0123] At least one of the fifth through eighth lenses may have a refractive index greater than 1.6 and negative refractive power. As an example, the sixth lens may have a refractive index greater than 1.6 and negative refractive power.

[0124] The optical imaging system according to the example implementation can be configured to be thin, even if it includes at least nine lenses.

[0125] Furthermore, the Fno of the optical imaging system is less than 2.3, and therefore the optical imaging system can be configured to be bright. In the example implementation, the Fno of the optical imaging system can be 1.8 or greater and less than 2.3.

[0126] Reference Figure 1 and Figure 2 An optical imaging system according to a first exemplary embodiment of the present disclosure is described.

[0127] The optical imaging system according to the first exemplary embodiment may 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, an eighth lens 180, and a ninth lens 190, and may also include an aperture, a filter IRCF, and an image sensor IS.

[0128] The characteristics of each lens (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) are shown in Table 1.

[0129] Table 1

[0130] Face number mark radius of curvature Thickness or distance Refractive index Abbe number focal length S1 First lens 2.754 1.026 1.544 56.1 6.862 S2 9.036 0.156 S3 Second lens 11.438 0.250 1.671 19.4 -21.149 S4 6.302 0.367 S5 Third lens 22.800 0.351 1.535 56.1 58.075 S6 84.507 0.236 S7 Fourth lens -72.785 0.300 1.671 19.4 -52.880 S8 70.558 0.099 S9 Fifth lens 14.866 0.353 1.544 56.1 66.313 S10 24.986 0.596 S11 Sixth lens 43.845 0.400 1.615 25.9 -13.706 S12 7.103 0.116 S13 Seventh Lens 6.293 0.450 1.535 56.1 40.259 S14 8.657 0.197 S15 Eighth lens 3.115 0.721 1.567 38.0 6.555 S16 17.205 1.125 S17 Ninth Lens -21.689 0.520 1.535 56.1 -5.507 S18 3.450 0.250 S19 Filter infinity 0.210 1.518 64.2 S20 infinity 0.767 S21 Imaging surface infinity

[0131] Meanwhile, the total focal length f of the optical imaging system according to the first example embodiment can be 7.14 mm, its Fno can be 1.95, and its IMG HT can be 7.15 mm.

[0132] In a first example embodiment, the first lens 110 may have positive refractive power, and its first surface may be convex while its second surface may be concave.

[0133] The second lens 120 may have negative refractive power, and its first surface may be convex while its second surface may be concave.

[0134] The third lens 130 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0135] The fourth lens 140 may have negative refractive power, and its first and second surfaces may be concave.

[0136] The fifth lens 150 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0137] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the fifth lens 150. For example, the first surface of the fifth lens 150 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the fifth lens 150 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0138] The sixth lens 160 may have negative refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0139] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the sixth lens 160 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0140] The seventh lens 170 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0141] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens 170 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0142] The eighth lens 180 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0143] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 180. For example, the first surface of the eighth lens 180 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens 180 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0144] The ninth lens 190 may have negative refractive power, and its first and second surfaces may be concave in the paraxial region.

[0145] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens 190. For example, the first surface of the ninth lens 190 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens 190 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0146] Meanwhile, each surface of the first lens 110 to the ninth lens 190 can have an aspherical coefficient as shown in Table 2. For example, all object-side and image-side surfaces of the first lens 110 to the ninth lens 190 can be aspherical.

[0147] Table 2

[0148]

[0149]

[0150] Reference Figure 3 and Figure 4 An optical imaging system according to a second exemplary embodiment of the present disclosure is described.

[0151] The optical imaging system according to the second exemplary embodiment may 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, an eighth lens 280, and a ninth lens 290, and may also include an aperture, a filter IRCF, and an image sensor IS.

[0152] The characteristics of each lens (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) are shown in Table 3.

[0153] Table 3

[0154]

[0155]

[0156] Meanwhile, the total focal length f of the optical imaging system according to the second example embodiment can be 7.1 mm, its Fno can be 1.95, and its IMG HT can be 7.15 mm.

[0157] In a second example embodiment, the first lens 210 may have positive refractive power, and its first surface may be convex while its second surface may be concave.

[0158] The second lens 220 may have negative refractive power, and its first surface may be convex while its second surface may be concave.

[0159] The third lens 230 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0160] The fourth lens 240 may have negative refractive power, and its first and second surfaces may be concave.

[0161] The fifth lens 250 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0162] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. Similarly, the second surface of the fifth lens 250 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0163] The sixth lens 260 may have negative refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0164] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. Similarly, the second surface of the sixth lens 260 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0165] The seventh lens 270 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0166] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens 270 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0167] The eighth lens 280 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0168] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 280. For example, the first surface of the eighth lens 280 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens 280 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0169] The ninth lens 290 may have negative refractive power, and its first and second surfaces may be concave in the paraxial region.

[0170] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens 290. For example, the first surface of the ninth lens 290 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens 290 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0171] Meanwhile, each surface of the first lens 210 to the ninth lens 290 can have an aspherical coefficient as shown in Table 4. For example, all object-side and image-side surfaces of the first lens 210 to the ninth lens 290 can be aspherical.

[0172] Table 4

[0173]

[0174]

[0175] Reference Figure 5 and Figure 6 An optical imaging system according to a third exemplary embodiment of the present disclosure is described.

[0176] The optical imaging system according to the third exemplary embodiment 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, an eighth lens 380, and a ninth lens 390, and may also include an aperture stop, an IRCF filter, and an image sensor IS.

[0177] The characteristics of each lens (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) are shown in Table 5.

[0178] Table 5

[0179]

[0180]

[0181] Meanwhile, the total focal length f of the optical imaging system according to the third example embodiment can be 5.88 mm, its Fno can be 2.00, and its IMG HT can be 6 mm.

[0182] In a third example embodiment, the first lens 310 may have positive refractive power, and its first surface may be convex while its second surface may be concave.

[0183] The second lens 320 can have negative refractive power, and its first surface can be convex while its second surface can be concave.

[0184] The third lens 330 can have negative refractive power, and its first surface can be convex while its second surface can be concave.

[0185] The fourth lens 340 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0186] The fifth lens 350 can have positive refractive power, and its first and second surfaces can be convex in the paraxial region.

[0187] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the fifth lens 350 may be convex in the paraxial region and concave in the portion other than the paraxial region.

[0188] The sixth lens 360 can have negative refractive power, and its first surface can be concave in the paraxial region, and its second surface can be convex in the paraxial region.

[0189] Furthermore, at least one inflection point may 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 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the sixth lens 360 may be convex in the paraxial region and concave in the portion other than the paraxial region.

[0190] The seventh lens 370 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0191] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens 370 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0192] The eighth lens 380 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0193] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 380. For example, the first surface of the eighth lens 380 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens 380 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0194] The ninth lens 390 can have negative refractive power, and its first and second surfaces can be concave in the paraxial region.

[0195] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens 390. For example, the first surface of the ninth lens 390 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens 390 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0196] Meanwhile, each surface of the first lens 310 to the ninth lens 390 can have an aspherical coefficient as shown in Table 6. For example, all object-side and image-side surfaces of the first lens 310 to the ninth lens 390 can be aspherical.

[0197] Table 6

[0198]

[0199]

[0200] Reference Figure 7 and Figure 8 An optical imaging system according to a fourth exemplary embodiment of the present disclosure is described.

[0201] The optical imaging system according to the fourth exemplary embodiment may include a first lens 410, a second lens 420, a third lens 430, a fourth lens 440, a fifth lens 450, a sixth lens 460, a seventh lens 470, an eighth lens 480, and a ninth lens 490, and may also include an aperture stop, an IRCF filter, and an image sensor IS.

[0202] The characteristics of each lens (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) are shown in Table 7.

[0203] Table 7

[0204] Face number mark radius of curvature Thickness or distance Refractive index Abbe number focal length S1 First lens 2.174 0.769 1.544 56.1 6.626 S2 4.768 0.085 S3 Second lens 6.594 0.250 1.671 19.4 -23.454 S4 4.588 0.259 S5 Third lens 5.432 0.284 1.661 20.4 97.758 S6 5.802 0.178 S7 Fourth lens 9.747 0.319 1.544 56.1 24.846 S8 34.238 0.094 S9 Fifth lens -8.720 0.341 1.567 38.0 -195.328 S10 -9.595 0.230 S11 Sixth lens 14.417 0.340 1.640 23.5 -17.581 S12 6.283 0.058 S13 Seventh Lens 5.110 0.450 1.640 23.5 18.707 S14 8.569 0.544 S15 Eighth lens 4.164 0.658 1.544 56.1 7.872 S16 126.915 0.627 S17 Ninth Lens -7.275 0.525 1.535 56.1 -5.152 S18 4.572 0.120 S19 Filter infinity 0.110 1.518 64.2 S20 infinity 0.760 S21 Imaging surface infinity

[0205] Meanwhile, the total focal length f of the optical imaging system according to the fourth example embodiment can be 5.7 mm, its Fno can be 2.1, and its IMG HT can be 6 mm.

[0206] In the fourth example embodiment, the first lens 410 may have positive refractive power, and its first surface may be convex while its second surface may be concave.

[0207] The second lens 420 can have negative refractive power, and its first surface can be convex while its second surface can be concave.

[0208] The third lens 430 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0209] The fourth lens 440 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0210] The fifth lens 450 may have negative refractive power, and its first surface may be concave in the paraxial region, and its second surface may be convex in the paraxial region.

[0211] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the fifth lens 450. For example, the first surface of the fifth lens 450 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the fifth lens 450 may be convex in the paraxial region and concave in the portion other than the paraxial region.

[0212] The sixth lens 460 may have negative refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0213] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the sixth lens 460. For example, the first surface of the sixth lens 460 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the sixth lens 460 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0214] The seventh lens 470 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0215] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the seventh lens 470. For example, the first surface of the seventh lens 470 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens 470 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0216] The eighth lens 480 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0217] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 480. For example, the first surface of the eighth lens 480 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens 480 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0218] The ninth lens 490 can have negative refractive power, and its first and second surfaces can be concave in the paraxial region.

[0219] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens 490. For example, the first surface of the ninth lens 490 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens 490 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0220] Meanwhile, each surface of the first lens 410 to the ninth lens 490 can have an aspherical coefficient as shown in Table 8. For example, all object-side and image-side surfaces of the first lens 410 to the ninth lens 490 can be aspherical.

[0221] Table 8

[0222]

[0223]

[0224] Reference Figure 9 and Figure 10 An optical imaging system according to a fifth exemplary embodiment of the present disclosure is described.

[0225] The optical imaging system according to the fifth exemplary embodiment may 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, an eighth lens 580, and a ninth lens 590, and may also include an aperture stop, an IRCF filter, and an image sensor IS.

[0226] The characteristics of each lens (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) are shown in Table 9.

[0227] Table 9

[0228]

[0229]

[0230] Meanwhile, the total focal length f of the optical imaging system according to the fifth exemplary embodiment can be 6 mm, its Fno can be 2.1, and its IMG HT can be 6 mm.

[0231] In the fifth example embodiment, the first lens 510 may have positive refractive power, and its first surface may be convex while its second surface may be concave.

[0232] The second lens 520 may have negative refractive power, and its first surface may be convex while its second surface may be concave.

[0233] The third lens 530 can have negative refractive power, and its first surface can be convex while its second surface can be concave.

[0234] The fourth lens 540 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0235] The fifth lens 550 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0236] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the fifth lens 550. For example, the first surface of the fifth lens 550 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the fifth lens 550 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0237] The sixth lens 560 may have negative refractive power, and its first surface may be concave in the paraxial region, and its second surface may be convex in the paraxial region.

[0238] Furthermore, at least one inflection point may 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 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the sixth lens 560 may be convex in the paraxial region and concave in the portion other than the paraxial region.

[0239] The seventh lens 570 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0240] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens 570 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0241] The eighth lens 580 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0242] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 580. For example, the first surface of the eighth lens 580 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens 580 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0243] The ninth lens 590 can have negative refractive power, and its first and second surfaces can be concave in the paraxial region.

[0244] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens 590. For example, the first surface of the ninth lens 590 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens 590 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0245] Meanwhile, each surface of the first lens 510 to the ninth lens 590 may have an aspherical coefficient as shown in Table 10. For example, all object-side and image-side surfaces of the first lens 510 to the ninth lens 590 may be aspherical.

[0246] Table 10

[0247]

[0248]

[0249] Reference Figure 11 and Figure 12 An optical imaging system according to a sixth exemplary embodiment of the present disclosure is described.

[0250] The optical imaging system according to the sixth exemplary embodiment may 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, an eighth lens 680, and a ninth lens 690, and may also include an aperture stop, a filter IRCF, and an image sensor IS.

[0251] The characteristics of each lens (radius of curvature, lens thickness or distance between lenses, refractive index, Abbe number, and focal length) are shown in Table 11.

[0252] Table 11

[0253] Face number mark radius of curvature Thickness or distance Refractive index Abbe number focal length S1 First lens 2.755 1.032 1.544 56.1 6.831 S2 9.161 0.180 S3 Second lens 11.929 0.250 1.671 19.4 -20.663 S4 6.384 0.382 S5 Third lens 24.732 0.356 1.535 56.1 63.208 S6 90.859 0.178 S7 Fourth lens -154.613 0.300 1.671 19.4 -51.288 S8 44.808 0.106 S9 Fifth lens 13.249 0.355 1.567 38.0 54.441 S10 23.037 0.606 S11 Sixth lens 43.330 0.400 1.615 25.9 -14.028 S12 7.218 0.113 S13 Seventh Lens 6.450 0.450 1.535 56.1 41.212 S14 8.884 0.209 S15 Eighth lens 3.158 0.702 1.567 38.0 6.636 S16 17.640 1.115 S17 Ninth Lens -21.611 0.520 1.535 56.1 -5.503 S18 3.449 0.250 S19 Filter infinity 0.210 1.518 64.2 S20 infinity 0.776 S21 Imaging surface infinity

[0254] Meanwhile, the total focal length f of the optical imaging system according to the sixth exemplary embodiment can be 7.15 mm, its Fno can be 1.9, and its IMG HT can be 7.15 mm.

[0255] In the sixth example embodiment, the first lens 610 may have positive refractive power, and its first surface may be convex while its second surface may be concave.

[0256] The second lens 620 can have negative refractive power, and its first surface can be convex while its second surface can be concave.

[0257] The third lens 630 can have positive refractive power, and its first surface can be convex while its second surface can be concave.

[0258] The fourth lens 640 may have negative refractive power, and its first and second surfaces may be concave.

[0259] The fifth lens 650 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0260] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the fifth lens 650 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0261] The sixth lens 660 may have negative refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0262] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the sixth lens 660 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0263] The seventh lens 670 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0264] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the seventh lens 670 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0265] The eighth lens 680 may have positive refractive power, and its first surface may be convex in the paraxial region, and its second surface may be concave in the paraxial region.

[0266] Furthermore, at least one inflection point may 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 may be convex in the paraxial region and concave in the portion other than the paraxial region. The second surface of the eighth lens 680 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0267] The ninth lens 690 can have negative refractive power, and its first and second surfaces can be concave in the paraxial region.

[0268] Furthermore, at least one inflection point may be formed on at least one of the first and second surfaces of the ninth lens 690. For example, the first surface of the ninth lens 690 may be concave in the paraxial region and convex in the portion other than the paraxial region. The second surface of the ninth lens 690 may be concave in the paraxial region and convex in the portion other than the paraxial region.

[0269] Meanwhile, each surface of the first lens 610 to the ninth lens 690 can have an aspherical coefficient as shown in Table 12. For example, all object-side and image-side surfaces of the first lens 610 to the ninth lens 690 can be aspherical.

[0270] Table 12

[0271]

[0272]

[0273] Table 13 shows the values ​​of the conditional expressions for the optical imaging system according to each example implementation.

[0274] Table 13

[0275]

[0276] As described above, the optical imaging system according to the example embodiments in this disclosure can achieve high resolution and has a reduced size.

[0277] While specific exemplary embodiments have been shown and described above, it will be apparent upon understanding this disclosure 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 should be understood in a descriptive sense only and not for limiting purposes. The description of features or aspects in each example should be understood as applicable to similar features or aspects in other examples. Appropriate results may still be achieved if the described techniques are performed in a different order, and / or if components in the described system, architecture, device, or circuit are combined in different ways and / or replaced or supplemented by other components or their equivalents. 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: The lenses arranged sequentially from the object side are: the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, and the ninth lens. The optical imaging system comprises a total of nine lenses with refractive power. The first lens has positive refractive power. The second lens has negative refractive power and a refractive index higher than 1.

6. Wherein, the third lens has positive refractive power, and the fourth and fifth lenses have refractive powers with opposite signs; or, the third lens has negative refractive power, and the fourth and fifth lenses each have positive refractive power. The sixth lens has negative refractive power, the seventh lens has positive refractive power, the eighth lens has positive refractive power, and the ninth lens has negative refractive power. The first lens has a convex object-side surface and a concave image-side surface; the second lens has a convex object-side surface and a concave image-side surface; the third lens has a convex object-side surface and a concave image-side surface; the fourth lens has a concave image-side surface; the seventh lens has a convex object-side surface and a concave image-side surface; the eighth lens has a convex object-side surface and a concave image-side surface; and the ninth lens has a concave object-side surface and a concave image-side surface. Where, 0.58 ≤ TTL / (2 IMG HT) < 0.61, where TTL is the distance along the optical axis from the object side of the first lens to the imaging plane, and IMG HT is half the diagonal length of the imaging plane. Wherein, 36.70 ≥ v1-v2 > 30, where v1 is the Abbe number of the first lens and v2 is the Abbe number of the second lens.

2. The optical imaging system according to claim 1, wherein, 1.779 ≤ TTL / ∑CT < 2, where ∑CT is the sum of the thicknesses of the first lens to the ninth lens along the optical axis.

3. The optical imaging system according to claim 1, wherein, 0.6 < f / f1 < 1.5, where f is the total focal length of the optical imaging system and f1 is the focal length of the first lens.

4. The optical imaging system according to claim 1, wherein, 1 < TTL / f < 1.25, where f is the total focal length of the optical imaging system.

5. The optical imaging system according to claim 1, wherein, 3.33 ≥ n2 + n3 > 3.15, where n2 is the refractive index of the second lens and n3 is the refractive index of the third lens.

6. The optical imaging system according to claim 1, wherein, 0.15 < BFL / f < 0.25, where f is the total focal length of the optical imaging system, and BFL is the distance along the optical axis from the image side of the ninth lens to the imaging plane.

7. The optical imaging system according to claim 1, wherein, 0.001 < D1 / f < 0.04, where D1 is the distance on the optical axis between the image-side surface of the first lens and the object-side surface of the second lens, and f is the total focal length of the optical imaging system.

8. The optical imaging system according to claim 1, wherein, 0.3 < R1 / f < 0.4, where R1 is the radius of curvature of the object side surface of the first lens, and f is the total focal length of the optical imaging system.

9. The optical imaging system according to claim 1, wherein, 1.90 ≤ Fno < 2.3, where Fno is the f-number of the optical imaging system.

10. The optical imaging system according to claim 1, wherein, 0.062 ≤ f1 / |f2| < 0.34, where f1 is the focal length of the first lens and f2 is the focal length of the second lens.

11. The optical imaging system according to claim 1, wherein, Either the third lens or the fourth lens has a refractive index higher than 1.6.

Images