Optical imaging system

Abstract

An optical imaging system. The 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, and an eighth lens, arranged sequentially from the object side towards the imaging plane. The first lens has positive refractive power, and the second lens has negative refractive power. The second and third lenses each have a refractive index greater than 1.66, and the optical imaging system satisfies the following condition: TTL / (2×IMG HT) < 0.64, where TTL is the distance from the object-side surface of the first lens to the optical axis of the imaging plane, and IMG HT is half the diagonal length of the imaging plane.

Description

Technical Field

[0001] The following description relates to an optical imaging system. Prior Technology

[0002] Portable terminal devices are equipped with cameras containing an optical imaging system consisting of multiple lenses to enable video calls and image capture.

[0003] Furthermore, as the operation and implementation of cameras in portable terminal devices gradually increase, the demand for high-resolution cameras in portable terminal devices is growing.

[0004] Recently, image sensors with high pixel counts (e.g., 13 to 100 million pixels) have been implemented in cameras of portable devices to achieve clearer image quality.

[0005] In other words, the size of the image sensor has increased, and therefore the total track length of the optical imaging system has also increased, which may ultimately cause the camera to protrude from portable terminal devices.

[0006] As portable devices become increasingly smaller, it will be advantageous for their cameras to have a slim form factor. Therefore, developing a slim optical imaging system that can still achieve high resolution is desirable. Summary of the Invention

[0007] This summary is provided to introduce a series of concepts in a simplified form, which are further elaborated in the detailed description of the invention. This summary is not intended to identify key or essential inventive concepts, nor is it intended to define the scope of the invention.

[0008] In general, the 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, and an eighth lens, wherein there are a total of eight lenses with refractive power. These lenses are arranged sequentially from the object side towards the imaging plane. The first lens has positive refractive power, and the second lens has negative refractive power. The second and third lenses each have a refractive index greater than 1.66. The optical imaging system satisfies the following condition: TTL / (2×IMG HT) < 0.64, where TTL is the distance from the object-side surface of the first lens to the imaging plane along the optical axis, and IMG HT is half the diagonal length of the imaging plane.

[0009] Each of at least three lenses (including the second and third lenses) from the first to the eighth lens may have a refractive index greater than 1.66, and among the at least three lenses with a refractive index greater than 1.66, the second lens has the smallest absolute value of focal length.

[0010] The fifth lens may have a refractive index greater than 1.66, and the optical imaging system satisfies the following conditional expression: |v1-(v2+v3+v5)| < 10, where v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, v3 is the Abbe number of the third lens, and v5 is the Abbe number of the fifth lens.

[0011] It may satisfy the following conditional expression: 25 < v1-v2 < 45; and 25 < v1-v3 < 45, where v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, and v3 is the Abbe number of the third lens.

[0012] It may satisfy the following conditional expression: 15 < v1-(v2+v3) < 25, where v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, and v3 is the Abbe number of the third lens.

[0013] It may satisfy the following conditional expression: 1.3 < Fno < 1.6, where Fno is the F-value of the optical imaging system.

[0014] It may satisfy the following conditional expression: 0.9 < f1 / f < 1.2, where f1 is the focal length of the first lens and f is the total focal length of the optical imaging system.

[0015] It may satisfy the following conditional expression: -3 < f2 / f < -1, where f2 is the focal length of the second lens and f is the total focal length of the optical imaging system.

[0016] It may satisfy the following conditional expression: |f3 / f| > 30, where f3 is the focal length of the third lens and f is the total focal length of the optical imaging system.

[0017] It may satisfy the following conditional expression: 0.3 < |f1 / f2| < 0.6, where f1 is the focal length of the first lens and f2 is the focal length of the second lens.

[0018] It may satisfy the following conditional expression: |f1 / f3| < 0.05, where f1 is the focal length of the first lens and f3 is the focal length of the third lens.

[0019] It may satisfy the following conditional expression: |f2 / f3| < 0.08, where f2 is the focal length of the second lens and f3 is the focal length of the third lens.

[0020] The following conditional expression may be satisfied: 1.3 < f12 / f < 1.7, where f12 is the composite focal length of the first and second lenses, and f is the overall focal length of the example optical imaging system.

[0021] The following conditional expression may be satisfied: 1.3 < f123 / f < 1.7, where f123 is the composite focal length of the first to third lenses, and f is the overall focal length of the example optical imaging system.

[0022] The fourth lens may have positive refractive power, and the fifth lens may have negative refractive power.

[0023] The sixth lens may have positive refractive power, the seventh lens may have positive refractive power, and the eighth lens may have negative refractive power.

[0024] Other features and aspects will become apparent from the following detailed description, drawings and claims. Simple Explanation of the Diagram

[0025] Figure 1 shows a configuration diagram of an example optical imaging system according to a first example embodiment. Figure 2 shows the aberration characteristics of the example optical imaging system shown in Figure 1. Figure 3 shows a configuration diagram of an example optical imaging system according to a second example embodiment. Figure 4 shows the aberration characteristics of the example optical imaging system shown in Figure 3. Figure 5 shows a configuration diagram of an example optical imaging system according to a third example embodiment. Figure 6 shows the aberration characteristics of the example optical imaging system shown in Figure 5.

[0026] Throughout the drawings and detailed descriptions, unless otherwise described or explained, it will be understood that the same reference numerals may refer to the same or similar elements, features, and structures. The drawings may not be drawn to scale, and the relative sizes, proportions, and depictions of elements in the drawings may be exaggerated for clarity, illustration, and convenience. Implementation

[0027] The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will become apparent after understanding the disclosure of this application. For example, the order of operations described herein is merely illustrative and is not limited to the order of operations presented herein; however, the order of operations may be altered, except for operations that must occur in a certain sequence, as will become apparent after understanding the disclosure of this application. Furthermore, for the purpose of improving clarity and conciseness, descriptions of features known in the art may be omitted.

[0028] The features described herein may be embodied in different forms and should not be construed as limited to the instances described herein. Rather, the instances described herein are merely illustrative of some of the many possible ways in which the methods, apparatus, and / or systems described herein will be apparent upon understanding the disclosure of this application. The term "may" is used herein with respect to instances or embodiments; for example, regarding what an instance or embodiment may include or implement, it means that at least one instance or embodiment includes or implements that feature, but not all instances are limited thereto. The terms "example" or "embodiment" as used herein have the same meaning; for example, the words "in one example" and "in one embodiment" have the same meaning, and "one or more examples" and "in one or more embodiments" have the same meaning.

[0029] The terminology used herein is for describing various instances only and is not intended to limit this disclosure. The articles “a,” “an,” and “the” are intended to include plural forms unless the context clearly indicates otherwise. As used herein, the term “and / or” includes any one of the listed items and any combination of any two or more of the associated enumerated items. As a non-limiting example, the terms “comprising” or “including” specify the presence of the stated feature, quantity, operation, member, element, and / or combination thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, members, elements, and / or combinations thereof, or the alternative presence of the stated features, quantities, operations, members, elements, and / or combinations thereof. Furthermore, while one embodiment may illustrate that the terms “comprising” or “including” specify the presence of the stated feature, quantity, operation, member, element, and / or combination thereof, other embodiments may exist in which one or more of the stated features, quantities, operations, members, elements, and / or combinations thereof are not present.

[0030] Throughout this specification, when a component or element is described as being "located," "connected to," "coupled to," or "attached to" another component, element, or layer, it may be directly (e.g., in contact with other components, elements, or layers) "located," "connected to," "coupled to," or "attached to" other components, elements, or layers, or one or more other components, elements, or layers may reasonably be present between them. When a component, element, or layer is described as being "directly located," "directly connected to," "directly coupled to," or "directly attached to" another component, element, or layer, no other components, elements, or layers may be present between them. Similarly, expressions such as "between" and "immediately between," as well as "adjacent to" and "directly adjacent to," can also be interpreted in the manner described above.

[0031] Although the terms "first," "second," and "third," or A, B, (a), (b), etc., may be used in this document to describe various members, components, regions, layers, or sections, these members, components, regions, layers, or sections should not be limited by these terms. Each of these terms is not intended to define the nature, order, or sequence of the corresponding member, component, region, layer, or section, but merely to distinguish the corresponding member, component, region, layer, or section from other members, components, regions, layers, or sections. Therefore, the first member, component, region, layer, or section referred to in the examples described herein may also be referred to as the second member, component, region, layer, or section without departing from the teachings of these examples.

[0032] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more. The terms "at least one of A, B and C", "at least one of A, B or C" and similar expressions are intended to be selective in meaning, and these terms "at least one of A, B and C", "at least one of A, B or C" and similar expressions also include instances where one or more of A, B and / or C may exist (e.g., any combination of one or more of each of A, B and C), unless the corresponding description and embodiments require that such enumeration (e.g., "at least one of A, B and C") be interpreted as having a connecting meaning.

[0033] One or more examples may provide an optical imaging system that can achieve high resolution and small overall length.

[0034] In the following one or more example embodiments of lens configurations, the thickness, size, and shape of the lenses are exaggerated for illustrative purposes. In particular, the spherical or aspherical shapes shown in the lens configuration diagrams are merely illustrative and are not limited thereto.

[0035] The first lens refers to the lens closest to the object side, and the eighth lens refers to the lens closest to the imaging plane (or image sensor).

[0036] Furthermore, in one or more examples, the values ​​of the lens's radius of curvature, thickness, distance, focal length, or similar parameters are all in millimeters (mm), while the field of view (FOV) is in degrees.

[0037] Furthermore, when describing the shape of each lens, a convex surface means that the paraxial region of that surface is convex, while a concave surface means that the paraxial region of that surface is concave. Therefore, even if a surface of a lens is described as convex, the edge portion of the lens may be concave. Similarly, even if a surface of a lens is described as concave, the edge portion of the lens may be convex.

[0038] The paraxial region refers to a very narrow region close to the optical axis.

[0039] An imaging plane can refer to a virtual plane where an optical imaging system forms a focal point. Alternatively, an imaging plane can refer to a surface of an image sensor that receives light.

[0040] An optical imaging system according to one or more example embodiments may include eight lenses.

[0041] In one example, an optical imaging system according to one embodiment may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens, arranged sequentially from the object side toward the imaging plane. The first lens through the eighth lens are spaced apart from each other at a predetermined distance along the optical axis.

[0042] An optical imaging system according to one or more embodiments may include not only eight lenses, but may also include other components as needed.

[0043] In one example, the example optical imaging system may further include an image sensor that converts an incident image of a subject into an electrical signal.

[0044] Furthermore, the example optical imaging system may further include an infrared filter (hereinafter referred to as the "filter") that blocks infrared light. The filter may be configured between the eighth lens and the image sensor.

[0045] Furthermore, the example optical imaging system may further include an aperture for controlling the amount of light.

[0046] According to one or more example embodiments, the first to eighth lenses constituting the example optical imaging system may be formed of a plastic material.

[0047] Furthermore, at least one of the first to eighth lenses may have an aspherical surface. Additionally, each of the first to eighth lenses may each have at least one aspherical surface.

[0048] In one example, at least one of the object-side surface and image-side surface of the first to eighth lenses may be aspherical. In this example, the aspherical surface of the first to eighth lenses can be represented by the following Equation 1:

[0049] Equation 1:

[0050] In Equation 1, c is the curvature of the lens (the reciprocal of the radius of curvature), K is the conic constant, and Y represents the distance from a point on the aspherical surface of the lens to the optical axis. Furthermore, the constants AH, J, and LP refer to the aspherical coefficients. Z(SAG) represents the distance along the optical axis between a point on the aspherical surface of the lens and the vertex of the aspherical surface.

[0051] An optical imaging system according to one or more example embodiments may satisfy at least one of the following conditional expressions.

[0052] According to one embodiment, the optical imaging system can satisfy the condition TTL / (2×IMG HT)<0.64. In this example, TTL is the distance along the optical axis from the object-side surface of the first lens to the imaging plane, and IMG HT is half the diagonal length of the imaging plane. Therefore, the optical imaging system can be miniaturized.

[0053] According to one embodiment, the optical imaging system can satisfy the condition 1.3 < Fno < 1.6. In this example, Fno is the F-value of the optical imaging system. Therefore, image brightness and resolution can be improved.

[0054] According to one embodiment, the optical imaging system can satisfy the condition 25 < v1 - v2 < 45. In this example, v1 is the Abbe number of the first lens, and v2 is the Abbe number of the second lens.

[0055] According to one embodiment, the optical imaging system can satisfy the condition 25 < v1 - v3 < 45. In this example, v3 is the Abbe number of the third lens.

[0056] According to one embodiment, the optical imaging system can satisfy the condition 15 < v1 - (v2 + v3) < 25.

[0057] According to one embodiment, the imaging lens can satisfy the condition |v1-(v2+v3+v5)| < 10. In this example, v5 is the Abbe number of the fifth lens.

[0058] According to one embodiment, the optical imaging system can satisfy the condition 0.9 < f1 / f < 1.2. In this example, f1 is the focal length of the first lens, and f is the total focal length of the optical imaging system.

[0059] According to one embodiment, the optical imaging system can satisfy the condition -3 < f2 / f < -1. In this example, f2 is the focal length of the second lens.

[0060] According to one embodiment, the optical imaging system can satisfy the condition |f3 / f| > 30. In this example, f3 is the focal length of the third lens.

[0061] According to one embodiment, the optical imaging system can satisfy the condition 2.5 < f4 / f < 5. In this example, f4 is the focal length of the fourth lens.

[0062] According to one embodiment, the optical imaging system can satisfy the condition -10 < f5 / f < -4. In this example, f5 is the focal length of the fifth lens.

[0063] According to one embodiment, the optical imaging system can satisfy the condition 0.3 < |f1 / f2| < 0.6.

[0064] According to one embodiment, the optical imaging system can satisfy the condition |f1 / f3| < 0.05.

[0065] According to one embodiment, the optical imaging system can satisfy the condition |f2 / f3| < 0.08.

[0066] According to one embodiment, the optical imaging system can satisfy the condition 1.3 < f12 / f < 1.7. In this example, f12 is the composite focal length of the first lens and the second lens.

[0067] According to one embodiment, the optical imaging system can satisfy the condition 1.3 < f123 / f < 1.7. In this example, f123 is the composite focal length of the first lens, the second lens, and the third lens.

[0068] The first to eighth lenses, which constitute an example optical imaging system according to one or more embodiments, will be described.

[0069] The first lens may have positive refractive power. Furthermore, the first lens may have a meniscus shape that convexes towards the object side. Additionally, the object-side surface of the first lens may be convex, and the imaging-side surface of the first lens may be concave.

[0070] At least one of the object-side surface or the imaging-side surface of the first lens may be aspherical. In one example, both the object-side surface and the imaging-side surface of the first lens may be aspherical.

[0071] The second lens may have negative refractive power. Furthermore, the second lens may have a meniscus shape that convexes towards the object side. Additionally, the object-side surface of the second lens may be convex, and the imaging-side surface of the second lens may be concave.

[0072] At least one of the object-side surface or the imaging-side surface of the second lens may be aspherical. In one example, both the object-side surface and the imaging-side surface of the second lens may be aspherical.

[0073] The third lens may have positive or negative refractive power. Furthermore, the third lens may have a meniscus shape that convexes towards the object side. Additionally, the object-side surface of the third lens may be convex, and the imaging-side surface may be concave.

[0074] At least one of the object-side surface or the imaging-side surface of the third lens may be aspherical. In one example, both the object-side surface and the imaging-side surface of the third lens may be aspherical.

[0075] The fourth lens may have positive refractive power. Furthermore, the fourth lens may have a meniscus shape that convexes towards the imaging side. Additionally, the object-side surface of the fourth lens may be concave, and the imaging-side surface of the fourth lens may be convex.

[0076] At least one of the object-side surface or the imaging-side surface of the fourth lens may be aspherical. For example, both the object-side surface and the imaging-side surface of the fourth lens may be aspherical.

[0077] The fifth lens may have negative refractive power. Furthermore, the fifth lens may have a meniscus shape that convexes towards the imaging side. The object-side surface of the fifth lens may be concave, and the imaging-side surface may be convex.

[0078] At least one of the object-side surface or the imaging-side surface of the fifth lens may be aspherical. For example, both the object-side surface and the imaging-side surface of the fifth lens may be aspherical.

[0079] The sixth lens may have positive refractive power. Furthermore, the sixth lens may have a meniscus shape that convexes towards the object side. Additionally, the object-side surface of the sixth lens may be convex, and the imaging-side surface of the sixth lens may be concave.

[0080] At least one of the object-side surface or the imaging-side surface of the sixth lens may be aspherical. For example, both the object-side surface and the imaging-side surface of the sixth lens may be aspherical.

[0081] The sixth lens may have at least one inflection point formed on at least one of the object-side surface and the imaging-side surface. For example, the object-side surface of the sixth lens may be convex in the paraxial region and concave in the portion outside the paraxial region. The imaging-side surface of the sixth lens may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0082] The seventh lens may have positive refractive power. Furthermore, the seventh lens may have a shape where both surfaces are convex. Additionally, the object-side surface and the image-side surface of the seventh lens may be convex.

[0083] At least one of the object-side surface or the imaging-side surface of the seventh lens may be aspherical. In one example, both the object-side surface and the imaging-side surface of the seventh lens may be aspherical.

[0084] Additionally, the seventh lens may have at least one inflection point formed on at least one of the object-side surface or the imaging-side surface. For example, the object-side surface of the seventh lens may be convex in the paraxial region and concave in the portion outside the paraxial region. The imaging-side surface of the seventh lens may be convex in the paraxial region and concave in the portion outside the paraxial region.

[0085] The eighth lens may have negative refractive power. Furthermore, the eighth lens may have a shape where both surfaces are concave. Additionally, the object-side surface and the image-side surface of the eighth lens may be concave.

[0086] At least one of the object-side surface or the imaging-side surface of the eighth lens may be aspherical. For example, both the object-side surface and the imaging-side surface of the eighth lens may be aspherical.

[0087] Additionally, the eighth lens may have at least one inflection point formed on at least one of the object-side surface or the imaging-side surface. In one example, the object-side surface of the eighth lens may be concave in the paraxial region and convex in the portion outside the paraxial region. The imaging-side surface of the eighth lens may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0088] The second and third lenses can each be configured to have a refractive index greater than that of the first lens.

[0089] In one embodiment, the second lens and the third lens may each have a refractive index greater than 1.66.

[0090] Of the first through eighth lenses, at least three lenses (including the second and third lenses) may have a refractive index greater than 1.66. In one example, the second, third, and fifth lenses may each have a refractive index greater than 1.66.

[0091] In one embodiment, the refractive index of the fifth lens may be greater than that of the second lens and the third lens, respectively. In one example, the fifth lens may have a refractive index greater than 1.68.

[0092] In the example optical imaging system, among lenses with a refractive index greater than 1.66, at least two lenses can be configured to have negative refractive power.

[0093] In the example optical imaging system, among lenses with a refractive index greater than 1.66, the absolute value of the focal length of the second lens may be the smallest.

[0094] The Abbe number of the third lens can be less than 50, the Abbe number of the fourth lens can be greater than 50, and the Abbe number of the fifth lens can be less than 50.

[0095] In addition, the Abbe number of the seventh lens and the Abbe number of the eighth lens can each be greater than 50.

[0096] An example optical imaging system according to a first embodiment will be described with reference to Figures 1 and 2.

[0097] An example optical imaging system according to the first 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, and an eighth lens 180, and may further include a filter 190 and an image sensor.

[0098] The optical imaging system according to the first embodiment can form a focal point (or a focused image) on an imaging plane 191. The imaging plane 191 can refer to the surface on which the optical imaging system forms the focal point. As an example, the imaging plane 191 can refer to a surface of an image sensor that receives light.

[0099] Table 1 below lists the lens characteristics (radius of curvature, lens thickness or inter-lens distance, refractive index, Abbe number or effective radius) for each lens. Table 1 surface Components radius of curvature Thickness or distance Refractive index Abbe number Effective radius S1 First lens 2.833 1.022 1.5463 55.99 2.060 S2 13.581 0.030 1.955 S3 Second lens 6.308 0.230 1.6789 19.24 1.853 S4 3.804 0.518 1.671 S5 Third lens 24.920 0.282 1.6789 19.24 1.660 S6 26.058 0.242 1.660 S7 Fourth lens -224.294 0.633 1.5463 55.99 1.730 S8 -11.048 0.143 1.932 S9 Fifth lens -10.328 0.239 1.6892 18.15 2.154 S10 -14.338 0.362 2.228 S11 Sixth lens 3.999 0.366 1.5707 37.40 2.843 S12 4.482 0.647 3.267 S13 Seventh Lens 6.378 0.640 1.5371 55.74 3.463 S14 -9.640 0.988 3.877 S15 Eighth lens -10.942 0.353 1.5371 55.74 4.357 S16 3.067 0.200 4.729 S17 filter unlimited 0.210 5.724 S18 unlimited 0.662 5.814 S19 Imaging plane unlimited 6.335

[0100] In the first embodiment, the first lens 110 may have positive refractive power, the object-side surface of the first lens 110 may be convex, and the image-side surface of the first lens 110 may be concave.

[0101] The second lens 120 may have negative refractive power, the object-side surface of the second lens 120 may be convex, and the image-side surface of the second lens 120 may be concave.

[0102] The third lens 130 may have positive refractive power, the object-side surface of the third lens 130 may be convex, and the image-side surface of the third lens 130 may be concave.

[0103] The fourth lens 140 may have positive refractive power, the object-side surface of the fourth lens 140 may be concave, and the image-side surface of the fourth lens 140 may be convex.

[0104] The fifth lens 150 may have negative refractive power, the object-side surface of the fifth lens 150 may be concave, and the image-side surface of the fifth lens 150 may be convex.

[0105] The sixth lens 160 may have positive refractive power, the object-side surface of the sixth lens 160 may be convex, and the image-side surface of the sixth lens 160 may be concave.

[0106] Furthermore, the sixth lens 160 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the sixth lens 160 may be convex in the paraxial region and concave in the portion outside the paraxial region. Similarly, the image-side surface of the sixth lens 160 may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0107] The seventh lens 170 may have positive refractive power, and the object-side surface and image-side surface of the seventh lens 170 may be convex in the paraxial region.

[0108] Furthermore, the seventh lens 170 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. For example, the object-side surface of the seventh lens 170 may be convex in the paraxial region and concave in the portion outside the paraxial region. Similarly, the image-side surface of the seventh lens 170 may be convex in the paraxial region and concave in the portion outside the paraxial region.

[0109] The eighth lens 180 may have negative refractive power, and the object-side surface and image-side surface of the eighth lens 180 may be concave in the paraxial region.

[0110] Furthermore, the eighth lens 180 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the eighth lens 180 may be concave in the paraxial region and convex in the portion outside the paraxial region. Similarly, the image-side surface of the eighth lens 180 may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0111] Each surface of the first lens 110 to the eighth lens 180 may have an aspherical coefficient, as shown in Table 2 below. In one example, both the object-side surface and the image-side surface of the first lens 110 to the eighth lens 180 may be aspherical. Table 2 S1 S2 S3 S4 S5 S6 S7 S8 Conical constant K -0.4617 9.7151 9.9950 1.8381 58.1439 67.4793 0 13.8497 Fourth coefficient A -6.605E-03 -2.257E-02 -3.052E-02 -2.455E-02 -2.762E-02 -3.043E-02 -1.53​​3E-02 1.267E-02 Sixth coefficient B 4.233E-02 6.911E-02 1.560E-02 8.912E-02 7.618E-02 7.739E-02 1.359E-02 9.711E-03 Eighth coefficient C -1.096E-01 -1.614E-01 1.112E-01 -3.633E-01 -3.757E-01 -3.168E-01 -3.339E-02 -2.338E-01 The tenth coefficient D 1.831E-01 2.970E-01 -4.718E-01 9.829E-01 1.161E+00 8.124E-01 7.612E-03 7.100E-01 The twelfth coefficient E -2.067E-01 -4.036E-01 1.003E+00 -1.754E+00 -2.443E+00 -1.428E+00 1.085E-01 -1.245E+00 The fourteenth coefficient F 1.637E-01 3.979E-01 -1.372E+00 2.140E+00 3.615E+00 1.800E+00 -2.758E-01 1.454E+00 The sixteenth coefficient G -9.315E-02 -2.855E-01 1.294E+00 -1.830E+00 -3.831E+00 -1.668E+00 3.655E-01 -1.190E+00 The eighteenth coefficient H 3.858E-02 1.498E-01 -8.647E-01 1.111E+00 2.933E+00 1.152E+00 -3.101E-01 6.984E-01 The twentieth coefficient J -1.166E-02 -5.740E-02 4.132E-01 -4.767E-01 -1.621E+00 -5.934E-01 1.784E-01 -2.957E-01 The twenty-second coefficient L 2.548E-03 1.586E-02 -1.402E-01 1.418E-01 6.396E-01 2.247E-01 -7.051E-02 8.953E-02 The twenty-fourth coefficient M -3.927E-04 -3.074E-03 3.302E-02 -2.787E-02 -1.754E-01 -6.071E-02 1.890E-02 -1.892E-02 The twenty-sixth coefficient N 4.054E-05 3.963E-04 -5.125E-03 3.273E-03 3.173E-02 1.105E-02 -3.284E-03 2.648E-03 The twenty-eighth coefficient O -2.518E-06 -3.049E-05 4.717E-04 -1.774E-04 -3.402E-03 -1.212E-03 3.337E-04 -2.208E-04 The thirtieth coefficient P 7.123E-08 1.058E-06 -1.950E-05 6.541E-07 1.635E-04 6.042E-05 -1.503E-05 8.293E-06 S9 S10 S11 S12 S13 S14 S15 S16 Conical constant K 0 0 0 0 1.4712 0 0 -4.9687 Fourth coefficient A 6.187E-02 4.212E-02 -1.566E-02 -2.726E-02 9.430E-03 3.452E-02 -5.536E-02 -4.766E-02 Sixth coefficient B -1.417E-01 -1.139E-01 -1.956E-02 -2.310E-03 -1.349E-02 -1.252E-02 1.110E-02 1.239E-02 Eighth coefficient C 1.940E-01 1.721E-01 3.587E-02 9.304E-03 7.221E-03 2.955E-03 -1.489E-03 -1.772E-03 The tenth coefficient D -2.314E-01 -2.222E-01 -3.730E-02 -6.406E-03 -3.372E-03 -5.965E-04 9.922E-05 -1.152E-04 The twelfth coefficient E 2.199E-01 2.247E-01 2.730E-02 2.487E-03 1.168E-03 7.335E-05 2.952E-05 1.253E-04 The fourteenth coefficient F -1.578E-01 -1.710E-01 -1.465E-02 -6.213E-04 -2.866E-04 1.131E-05 -8.903E-06 -3.172E-05 The sixteenth coefficient G 8.363E-02 9.689E-02 5.785E-03 1.040E-04 4.818E-05 -8.717E-06 1.010E-06 4.730E-06 The eighteenth coefficient H -3.225E-02 -4.069E-02 -1.672E-03 -1.182E-05 -5.437E-06 2.255E-06 -4.733E-08 -4.707E-07 The twentieth coefficient J 8.928E-03 1.258E-02 3.506E-04 9.066E-07 4.031E-07 -3.398E-07 -1.109E-09 3.246E-08 The twenty-second coefficient L -1.742E-03 -2.818E-03 -5.251E-05 -4.520E-08 -1.883E-08 3.266E-08 2.811E-10 -1.557E-09 The twenty-fourth coefficient M 2.326E-04 4.444E-04 5.458E-06 1.333E-09 5.023E-10 -2.033E-09 -1.713E-11 5.105E-11 The twenty-sixth coefficient N -2.016E-05 -4.672E-05 -3.732E-07 -1.776E-11 -5.843E-12 7.957E-11 5.456E-13 -1.089E-12 The twenty-eighth coefficient O 1.023E-06 2.934E-06 1.507E-08 0 0 -1.785E-12 -9.262E-15 1.362E-14 The thirtieth coefficient P -2.322E-08 -8.320E-08 -2.721E-10 0 0 1.754E-14 6.645E-17 -7.571E-17

[0112] Furthermore, the example optical imaging system configured as described above may have aberration characteristics as shown in Figure 2.

[0113] Referring to Figures 3 and 4, an example optical imaging system according to the second embodiment will be described.

[0114] An example optical imaging system 200 according to the second 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, and an eighth lens 280, and may further include a filter 290 and an image sensor.

[0115] The example optical imaging system according to the second embodiment can form a focal point (or focused image) on an imaging plane 291. The imaging plane 291 can refer to the surface on which the optical imaging system forms the focal point. In one example, the imaging plane 291 can refer to a surface of an image sensor that receives light.

[0116] The lens characteristics (radius of curvature, lens thickness or inter-lens distance, refractive index, Abbe number or effective radius) of each lens are shown in Table 3 below. Table 3 surface Components radius of curvature Thickness or distance Refractive index Abbe number Effective radius S1 First lens 2.832 1.008 1.5463 55.99 2.053 S2 13.538 0.047 1.952 S3 Second lens 6.293 0.230 1.6789 19.24 1.859 S4 3.918 0.545 1.692 S5 Third lens 39.233 0.238 1.6789 19.24 1.682 S6 32.694 0.258 1.649 S7 Fourth lens -116.716 0.645 1.5463 55.99 1.612 S8 -10.004 0.108 1.777 S9 Fifth lens -11.620 0.230 1.6892 18.15 1.934 S10 -23.516 0.338 2.078 S11 Sixth lens 3.993 0.361 1.5707 37.40 2.686 S12 4.667 0.714 3.123 S13 Seventh Lens 6.350 0.680 1.5371 55.74 3.575 S14 -9.860 1.001 3.922 S15 Eighth lens -11.740 0.301 1.5371 55.74 4.376 S16 2.901 0.194 4.695 S17 filter unlimited 0.210 5.713 S18 unlimited 0.700 5.803 S19 Imaging plane unlimited 6.333

[0117] In the second embodiment, the first lens 210 may have positive refractive power, the object-side surface of the first lens 210 may be convex, and the image-side surface of the first lens 210 may be concave.

[0118] The second lens 220 may have negative refractive power, the object-side surface of the second lens 220 may be convex, and the image-side surface of the second lens 220 may be concave.

[0119] The third lens 230 may have negative refractive power, the object-side surface of the third lens 230 may be convex, and the image-side surface of the third lens 230 may be concave.

[0120] The fourth lens 240 may have positive refractive power, the object-side surface of the fourth lens 240 may be concave, and the image-side surface of the fourth lens 240 may be convex.

[0121] The fifth lens 250 may have negative refractive power, the object-side surface of the fifth lens 250 may be concave, and the image-side surface of the fifth lens 250 may be convex.

[0122] The sixth lens 260 may have positive refractive power, the object-side surface of the sixth lens 260 may be convex, and the image-side surface of the sixth lens 260 may be concave.

[0123] Furthermore, the sixth lens 260 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the sixth lens 260 may be convex in the paraxial region and concave in the portion outside the paraxial region. Similarly, the image-side surface of the sixth lens 260 may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0124] The seventh lens 270 may have positive refractive power, and the object-side surface and image-side surface of the seventh lens 270 may be convex in the paraxial region.

[0125] Furthermore, the seventh lens 270 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the seventh lens 270 may be convex in the paraxial region and concave in the portion outside the paraxial region. The image-side surface of the seventh lens 270 may be convex in the paraxial region and concave in the portion outside the paraxial region.

[0126] The eighth lens 280 may have negative refractive power, and the object-side surface and image-side surface of the eighth lens 280 may be concave in the paraxial region.

[0127] Furthermore, the eighth lens 280 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the eighth lens 280 may be concave in the paraxial region and convex in the portion outside the paraxial region. The image-side surface of the eighth lens 280 may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0128] Each surface of the first lens 210 to the eighth lens 280 may have an aspherical coefficient, as shown in Table 4 below. In one example, both the object-side surface and the image-side surface of the first lens 210 to the eighth lens 280 may be aspherical. Table 4 S1 S2 S3 S4 S5 S6 S7 S8 Conical constant K -0.4385 8.8287 10.0141 1.9458 13.9479 43.0228 0 13.5255 Fourth coefficient A -5.141E-03 -2.145E-02 -2.590E-02 -1.148E-02 -1.945E-02 -2.104E-02 1.138E-02 2.915E-02 Sixth coefficient B 3.731E-02 1.032E-01 -8.006E-03 -4.826E-02 -3.484E-02 -4.355E-02 -1.870E-01 -1.037E-01 Eighth coefficient C -1.061E-01 -4.125E-01 1.477E-01 3.183E-01 2.445E-01 3.586E-01 7.787E-01 1.071E-01 The tenth coefficient D 2.011E-01 1.090E+00 -4.309E-01 -1.014E+00 -9.145E-01 -1.502E+00 -2.109E+00 7.813E-02 The twelfth coefficient E -2.608E-01 -1.871E+00 7.426E-01 2.095E+00 2.114E+00 3.819E+00 3.914E+00 -4.458E-01 The fourteenth coefficient F 2.381E-01 2.171E+00 -8.772E-01 -3.016E+00 -3.264E+00 -6.395E+00 -5.147E+00 7.286E-01 The sixteenth coefficient G -1.557E-01 -1.757E+00 7.461E-01 3.120E+00 3.511E+00 7.380E+00 4.886E+00 -7.052E-01 The eighteenth coefficient H 7.362E-02 1.011E+00 -4.649E-01 -2.348E+00 -2.691E+00 -6.012E+00 -3.374E+00 4.569E-01 The twentieth coefficient J -2.518E-02 -4.162E-01 2.123E-01 1.286E+00 1.480E+00 3.489E+00 1.694E+00 -2.062E-01 The twenty-second coefficient L 6.162E-03 1.218E-01 -7.020E-02 -5.062E-01 -5.806E-01 -1.434E+00 -6.114E-01 6.526E-02 The twenty-fourth coefficient M -1.051E-03 -2.472E-02 1.632E-02 1.395E-01 1.586E-01 4.078E-01 1.544E-01 -1.424E-02 The twenty-sixth coefficient N 1.186E-04 3.310E-03 -2.527E-03 -2.553E-02 -2.871E-02 -7.638E-02 -2.587E-02 2.042E-03 The twenty-eighth coefficient O -7.948E-06 -2.629E-04 2.337E-04 2.785E-03 3.094E-03 8.474E-03 2.584E-03 -1.736E-04 The thirtieth coefficient P 2.395E-07 9.378E-06 -9.759E-06 -1.371E-04 -1.504E-04 -4.218E-04 -1.164E-04 6.627E-06 S9 S10 S11 S12 S13 S14 S15 S16 Conical constant K 0 0 0 0 1.4602 0 0 -4.8779 Fourth coefficient A 7.932E-02 6.138E-02 -1.797E-02 -2.615E-02 1.153E-02 4.049E-02 -6.022E-02 -5.652E-02 Sixth coefficient B -2.219E-01 -2.040E-01 -2.864E-02 -1.190E-02 -1.493E-02 -2.020E-02 9.318E-03 1.682E-02 Eighth coefficient C 3.479E-01 3.787E-01 5.059E-02 2.084E-02 7.581E-03 9.732E-03 3.060E-03 -3.025E-03 The tenth coefficient D -3.825E-01 -5.164E-01 -4.856E-02 -1.352E-02 -3.437E-03 -4.733E-03 -2.678E-03 1.299E-04 The twelfth coefficient E 2.754E-01 5.116E-01 3.294E-02 5.358E-03 1.199E-03 1.765E-03 9.438E-04 8.471E-05 The fourteenth coefficient F -1.162E-01 -3.720E-01 -1.677E-02 -1.429E-03 -2.978E-04 -4.621E-04 -1.991E-04 -2.536E-05 The sixteenth coefficient G 1.388E-02 2.005E-01 6.435E-03 2.626E-04 5.050E-05 8.441E-05 2.776E-05 3.861E-06 The eighteenth coefficient H 1.497E-02 -8.038E-02 -1.844E-03 -3.332E-05 -5.730E-06 -1.083E-05 -2.683E-06 -3.791E-07 The twentieth coefficient J -1.074E-02 2.384E-02 3.886E-04 2.868E-06 4.268E-07 9.802E-07 1.832E-07 2.546E-08 The twenty-second coefficient L 3.714E-03 -5.153E-03 -5.896E-05 -1.601E-07 -2.003E-08 -6.202E-08 -8.852E-09 -1.181E-09 The twenty-fourth coefficient M -7.831E-04 7.880E-04 6.237E-06 5.225E-09 5.374E-10 2.680E-09 2.964E-10 3.723E-11 The twenty-sixth coefficient N 1.022E-04 -8.068E-05 -4.351E-07 -7.577E-11 -6.294E-12 -7.510E-11 -6.552E-12 -7.597E-13 The twenty-eighth coefficient O -7.606E-06 4.956E-06 1.794E-08 0 0 1.225E-12 8.606E-14 9.027E-15 The thirtieth coefficient P 2.479E-07 -1.380E-07 -3.305E-10 0 0 -8.780E-15 -5.088E-16 -4.726E-17

[0129] Furthermore, the example optical imaging system configured as described above may have the aberration characteristics shown in Figure 4.

[0130] Referring to Figures 5 and 6, an example optical imaging system according to a third embodiment will be described.

[0131] An example optical imaging system 300 according to a third 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, and an eighth lens 380, and may further include a filter 390 and an image sensor.

[0132] The optical imaging system according to the third embodiment can form a focal point (or a focused image) on an imaging plane 391. The imaging plane 391 may refer to the surface on which the optical imaging system forms the focal point. In one example, the imaging plane 391 may refer to a surface of an image sensor that receives light.

[0133] The lens characteristics (radius of curvature, lens thickness or inter-lens distance, refractive index, Abbe number or effective radius) of each lens are shown in Table 5 below. Table 5 surface Components radius of curvature Thickness or distance Refractive index Abbe number Effective radius S1 First lens 2.832 1.004 1.5463 55.99 2.040 S2 13.528 0.049 1.946 S3 Second lens 6.290 0.230 1.6789 19.24 1.855 S4 3.945 0.540 1.694 S5 Third lens 45.138 0.246 1.6789 19.24 1.680 S6 37.615 0.262 1.645 S7 Fourth lens -78.965 0.680 1.5463 55.99 1.698 S8 -9.861 0.122 1.929 S9 Fifth lens -10.602 0.230 1.6892 18.15 2.114 S10 -20.632 0.352 2.205 S11 Sixth lens 3.805 0.402 1.5371 55.74 2.724 S12 4.443 0.689 3.164 S13 Seventh Lens 6.298 0.677 1.5371 55.74 3.483 S14 -10.214 0.981 3.893 S15 Eighth lens -12.235 0.308 1.5371 55.74 4.321 S16 2.801 0.198 4.700 S17 filter unlimited 0.210 5.705 S18 unlimited 0.673 5.795 S19 Imaging plane unlimited 0.027 6.329

[0134] In the third embodiment, the first lens 310 may have positive refractive power, the object-side surface of the first lens 310 may be convex, and the image-side surface of the first lens 310 may be concave.

[0135] The second lens 320 may have negative refractive power, the object-side surface of the second lens 320 may be convex, and the image-side surface of the second lens 320 may be concave.

[0136] The third lens 330 may have negative refractive power, the object-side surface of the third lens 330 may be convex, and the image-side surface of the third lens 330 may be concave.

[0137] The fourth lens 340 may have positive refractive power, the object-side surface of the fourth lens 340 may be concave, and the image-side surface of the fourth lens 340 may be convex.

[0138] The fifth lens 350 may have negative refractive power, the object-side surface of the fifth lens 350 may be concave, and the image-side surface of the fifth lens 350 may be convex.

[0139] The sixth lens 360 may have positive refractive power, the object-side surface of the sixth lens 360 may be convex, and the image-side surface of the sixth lens 360 may be concave.

[0140] Furthermore, the sixth lens 360 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. For example, the object-side surface of the sixth lens 360 may be convex in the paraxial region and concave in the portion outside the paraxial region. The image-side surface of the sixth lens 360 may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0141] The seventh lens 370 may have positive refractive power, and the object-side surface and image-side surface of the seventh lens 370 may be convex in the paraxial region.

[0142] Furthermore, the seventh lens 370 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the seventh lens 370 may be convex in the paraxial region and concave in the portion outside the paraxial region. The image-side surface of the seventh lens 370 may be convex in the paraxial region and concave in the portion outside the paraxial region.

[0143] The eighth lens 380 may have negative refractive power, and the object-side surface and image-side surface of the eighth lens 380 may be concave.

[0144] Furthermore, the eighth lens 380 may have at least one inflection point formed on at least one of its object-side surface or image-side surface. In one example, the object-side surface of the eighth lens 380 may be concave in the paraxial region and convex in the portion outside the paraxial region. The image-side surface of the eighth lens 380 may be concave in the paraxial region and convex in the portion outside the paraxial region.

[0145] Each surface of the first lens 310 to the eighth lens 380 may have an aspherical coefficient, as shown in Table 6 below. In one example, both the object-side surface and the image-side surface of the first lens 310 to the eighth lens 380 may be aspherical. Table 6 S1 S2 S3 S4 S5 S6 S7 S8 Conical constant K -0.4419 8.9994 10.0172 1.9520 4.5487 40.4614 0 13.5180 Fourth coefficient A -6.650E-03 -1.205E-02 -2.394E-02 -9.797E-03 -1.587E-02 -2.464E-02 1.195E-02 2.703E-02 Sixth coefficient B 3.283E-02 2.557E-02 -1.972E-02 -6.239E-02 -5.845E-02 1.805E-02 -2.111E-01 -9.816E-02 Eighth coefficient C -6.050E-02 -1.180E-01 1.399E-01 3.717E-01 2.854E-01 -7.497E-02 9.315E-01 1.314E-01 The tenth coefficient D 6.317E-02 4.315E-01 -2.516E-01 -1.136E+00 -8.327E-01 1.557E-01 -2.580E+00 -6.639E-02 The twelfth coefficient E -3.042E-02 -9.076E-01 1.948E-01 2.302E+00 1.614E+00 -1.236E-01 4.778E+00 -9.908E-02 The fourteenth coefficient F -7.814E-03 1.195E+00 1.248E-02 -3.322E+00 -2.203E+00 -1.273E-01 -6.173E+00 2.325E-01 The sixteenth coefficient G 2.287E-02 -1.054E+00 -1.741E-01 3.502E+00 2.183E+00 4.387E-01 5.700E+00 -2.359E-01 The eighteenth coefficient H -1.739E-02 6.455E-01 1.828E-01 -2.720E+00 -1.595E+00 -5.393E-01 -3.807E+00 1.500E-01 The twentieth coefficient J 7.774E-03 -2.791E-01 -1.060E-01 1.549E+00 8.592E-01 3.943E-01 1.841E+00 -6.493E-02 The twenty-second coefficient L -2.279E-03 8.499E-02 3.940E-02 -6.379E-01 -3.377E-01 -1.879E-01 -6.380E-01 1.952E-02 The twenty-fourth coefficient M 4.455E-04 -1.786E-02 -9.615E-03 1.845E-01 9.417E-02 5.915E-02 1.543E-01 -4.029E-03 The twenty-sixth coefficient N -5.613E-05 2.467E-03 1.495E-03 -3.548E-02 -1.765E-02 -1.190E-02 -2.473E-02 5.464E-04 The twenty-eighth coefficient O 4.139E-06 -2.015E-04 -1.345E-04 4.072E-03 1.995E-03 1.390E-03 2.358E-03 -4.397E-05 The thirtieth coefficient P -1.359E-07 7.381E-06 5.331E-06 -2.109E-04 -1.027E-04 -7.182E-05 -1.012E-04 1.595E-06 S9 S10 S11 S12 S13 S14 S15 S16 Conical constant K 0 0 0 0 1.4646 0 0 -5.4055 Fourth coefficient A 8.848E-02 5.960E-02 -1.292E-02 -2.271E-02 1.382E-02 4.117E-02 -6.295E-02 -6.032E-02 Sixth coefficient B -2.798E-01 -2.067E-01 -4.467E-02 -1.699E-02 -1.935E-02 -2.055E-02 9.727E-03 2.148E-02 Eighth coefficient C 5.347E-01 3.853E-01 7.675E-02 2.522E-02 1.127E-02 9.048E-03 5.255E-03 -5.490E-03 The tenth coefficient D -7.482E-01 -5.169E-01 -7.538E-02 -1.577E-02 -5.318E-03 -3.828E-03 -4.310E-03 1.030E-03 The twelfth coefficient E 7.543E-01 4.991E-01 5.152E-02 6.055E-03 1.838E-03 1.247E-03 1.508E-03 -1.53​​8E-04 The fourteenth coefficient F -5.550E-01 -3.518E-01 -2.584E-02 -1.557E-03 -4.463E-04 -2.844E-04 -3.172E-04 1.980E-05 The sixteenth coefficient G 3.014E-01 1.832E-01 9.634E-03 2.757E-04 7.422E-05 4.411E-05 4.430E-05 -2.204E-06 The eighteenth coefficient H -1.212E-01 -7.077E-02 -2.667E-03 -3.373E-05 -8.331E-06 -4.524E-06 -4.298E-06 1.992E-07 The twentieth coefficient J 3.584E-02 2.019E-02 5.429E-04 2.809E-06 6.187E-07 2.852E-07 2.953E-07 -1.365E-08 The twenty-second coefficient L -7.680E-03 -4.194E-03 -7.988E-05 -1.522E-07 -2.913E-08 -8.283E-09 -1.436E-08 6.767E-10 The twenty-fourth coefficient M 1.158E-03 6.164E-04 8.234E-06 4.851E-09 7.884E-10 -1.787E-10 4.843E-10 -2.324E-11 The twenty-sixth coefficient N -1.165E-04 -6.073E-05 -5.626E-07 -6.901E-11 -9.346E-12 2.451E-11 -1.078E-11 5.222E-13 The twenty-eighth coefficient O 7.026E-06 3.599E-06 2.284E-08 0 0 -8.225E-13 1.425E-13 -6.884E-15 The thirtieth coefficient P -1.927E-07 -9.696E-08 -4.162E-10 0 0 1.004E-14 -8.477E-16 4.031E-17

[0146] Furthermore, the example optical imaging system configured as described above may have the aberration characteristics shown in Figure 6. Table 7 First Embodiment Second Embodiment Third Embodiment Fno 1.522 1.535 1.561 TTL 7.767 7.808 7.880 IMG HT 6.329 6.329 6.329 FOV 89.12 88.25 87.358 f 6.114 6.262 6.357 f1 6.340 6.344 6.346 f2 -14.666 -15.917 -16.231 f3 763.536 -293.262 -336.893 f4 21.246 19.984 20.554 f5 -54.932 -33.597 -31.945 f6 51.018 40.583 40.389 f7 7.247 7.297 7.358 f8 -4.421 -4.300 -4.213 f12 9.766 9.356 9.271 f123 9.628 9.564 9.447

[0147] In Table 7, Fno is the F-value of the example optical imaging system, TTL is the distance on the optical axis from the object-side surface of the first lens to the imaging plane, IMG HT is half the diagonal length of the imaging plane, and FOV is the view angle of the optical imaging system.

[0148] f is the total focal length of the optical imaging system, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, f7 is the focal length of the seventh lens, and f8 is the focal length of the eighth lens.

[0149] An example optical imaging system according to one or more embodiments can reduce size while achieving high resolution.

[0150] While this disclosure includes specific examples, it will be apparent to those skilled in the art, upon understanding the disclosure of this application, that various changes in the form and detail of these examples may be made without departing from the spirit and scope of the claims and their equivalents. The examples described herein should be considered in a descriptive sense only and not for limiting purposes. Features or aspects described in each example should be considered applicable to similar features or aspects in other examples. Appropriate results may be obtained if the described techniques are performed in a different order, and / or if the components in the described system, architecture, apparatus, or circuit are combined in a different manner, and / or replaced or supplemented by other components or their equivalents.

[0151] Therefore, in addition to the above content and all the schematic disclosures, the scope of this disclosure also includes the scope of the patent application and its equivalents, that is, all variations within the scope of the patent application and its equivalents should be interpreted as being included in this disclosure.

[0152] 110, 210, 310: First lens 120, 220, 320: Second lens 130, 230, 330: Third lens 140, 240, 340: Fourth lens 150, 250, 350: Fifth lens 160, 260, 360: Sixth lens 170, 270, 370: Seventh Lens 180, 280, 380: Eighth lens 190, 290, 390: Filters 191, 291, 391: Imaging planes 200, 300: Example optical imaging systems

Claims

1. An optical imaging system, comprising: A first lens has positive refractive power, a convex object-side surface, and a concave imaging-side surface; A second lens having negative refractive power, a convex object-side surface, and a concave imaging-side surface; a third lens having refractive power, a convex object-side surface, and a concave imaging-side surface; a fourth lens having positive refractive power, a concave object-side surface, and a convex imaging-side surface; a fifth lens having negative refractive power; a sixth lens having refractive power; a seventh lens having positive refractive power; and an eighth lens having negative refractive power and a concave imaging-side surface, wherein the first to the eighth lenses are arranged sequentially from the object side to the imaging plane, wherein the optical imaging system has a total of eight lenses with refractive power, and wherein the optical imaging system satisfies the following conditional expression: -10 < f5 / f < -4. 1.3 < f12 / f < 1.7; and 25 < v1-v3 < 45, where f5 is the focal length of the fifth lens, f is the total focal length of the optical imaging system, f12 is the composite focal length of the first and second lenses, v1 is the Abbe number of the first lens, and v3 is the Abbe number of the third lens.

2. The optical imaging system as claimed in claim 1, wherein the following condition is satisfied: 0.9 < f1 / f < 1.2, where f1 is the focal length of the first lens.

3. The optical imaging system as claimed in claim 1, wherein the following conditional expression is satisfied: -3 < f2 / f < -1, where f2 is the focal length of the second lens.

4. The optical imaging system as claimed in claim 1, wherein the following condition expression is satisfied: |f3 / f| > 30, where f3 is the focal length of the third lens.

5. The optical imaging system of claim 1, wherein the following conditional expression is satisfied: 0.3 < |f1 / f2| < 0.6, where f1 is the focal length of the first lens and f2 is the focal length of the second lens.

6. The optical imaging system of claim 1, wherein the following condition is satisfied: |f1 / f3| < 0.05, where f1 is the focal length of the first lens and f3 is the focal length of the third lens.

7. The optical imaging system of claim 1, wherein the following condition expression is satisfied: |f2 / f3| < 0.08, where f2 is the focal length of the second lens and f3 is the focal length of the third lens.

8. The optical imaging system of claim 1, wherein the following condition is satisfied: 1.3 < f123 / f < 1.7, where f123 is the composite focal length of the first lens to the third lens.

9. The optical imaging system of claim 1, wherein the optical imaging system satisfies the conditional expression TTL / (2×IMG HT) < 0.64, where TTL is the distance on the optical axis from the object-side surface of the first lens to the imaging plane, and IMG HT is half the diagonal length of the imaging plane.

10. The optical imaging system of claim 1, wherein the following condition is satisfied: 1.3 < Fno < 1.6, where Fno is the F-number of the optical imaging system.

11. The optical imaging system of claim 1, wherein the second lens and the third lens each have a refractive index greater than 1.

66.

12. The optical imaging system of claim 1, wherein at least three of the first to eighth lenses, including the second and third lenses, each has a refractive index greater than 1.66, and among the at least three lenses having a refractive index greater than 1.66, the absolute value of the focal length of the second lens is the smallest absolute value.

13. The optical imaging system of claim 1, wherein the fifth lens has a refractive index greater than 1.

66.

14. The optical imaging system of claim 1, wherein the optical imaging system satisfies the following conditional expression: |v1-(v2+v3+v5)| < 10, where v2 is the Abbe number of the second lens and v5 is the Abbe number of the fifth lens.

15. The optical imaging system of claim 1, wherein the following condition is satisfied: 25 < v1 - v2 < 45, where v2 is the Abbe number of the second lens.

16. The optical imaging system of claim 1, wherein the following condition is satisfied: 15 < v1 - (v2 + v3) < 25, where v2 is the Abbe number of the second lens.

17. The optical imaging system of claim 1, wherein the third lens has positive diopter.

18. The optical imaging system of claim 1, wherein the seventh lens has a convex object-side surface.

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