CN115616738A

CN115616738A - Optical imaging system

Info

Publication number: CN115616738A
Application number: CN202211270605.3A
Authority: CN
Inventors: 李知秀; 张东赫; 朴一容
Original assignee: Samsung Electro Mechanics Co Ltd
Current assignee: Samsung Electro Mechanics Co Ltd
Priority date: 2021-11-26
Filing date: 2022-10-11
Publication date: 2023-01-17

Abstract

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, which are arranged in this order from an object side. The first lens has a positive refractive power, and the second lens has a negative refractive power. At least three lenses of the first lens to the eighth lens each have a refractive index of 1.61 or more, and satisfy (TTL/(2 × IMG HT)) × (TTL/f) <0.64, where TTL is a distance from an object-side surface of the first lens to an imaging surface on an optical axis, IMG HT is half a diagonal length of the imaging surface, and f is a total focal length of the first lens to the eighth lens.

Description

Optical imaging system

Cross Reference to Related Applications

This application claims the benefit of priority from korean patent application No. 10-2021-0165683, filed on korean intellectual property office at 26/11/2021, and korean patent application No. 10-2022-0038122, filed on korean intellectual property office at 28/3/2022, the entire disclosures of which are incorporated herein by reference for all purposes.

Technical Field

The following description relates to an optical imaging system.

Background

Recent portable terminals include a camera equipped with an optical imaging system and a plurality of lenses to implement a video call and acquire an image.

As the functions of cameras in portable terminals are gradually increased, the demand for cameras having higher resolutions in portable terminals is also gradually increased.

Recently, image sensors having a high pixel count (e.g., 1300 ten thousand to 1 hundred million pixels, etc.) have been used in cameras of portable terminal devices to achieve clearer image quality.

However, as the size of the image sensor increases, the total length of the optical system thereof also increases accordingly, so that the camera may protrude from the portable terminal device, which may be problematic.

Disclosure of Invention

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In a 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, and an eighth lens, which are arranged in this order from an object side. The first lens has a positive refractive power, and the second lens has a negative refractive power. At least three lenses of the first lens to the eighth lens each have a refractive index of 1.61 or more, and satisfy (TTL/(2 × IMG HT)) × (TTL/f) <0.64, where TTL is a distance from an object-side surface of the first lens to an imaging plane on an optical axis, IMG HT is half a diagonal length of the imaging plane, and f is a total focal length of the optical imaging system.

The second lens may have a refractive index of 1.61 or more. Among the at least three lenses having refractive indices of 1.61 or more, an absolute value of a focal length of a second lens of the at least three lenses may be the smallest.

In the optical imaging system, any one or any combination of any two or more of 25-n (v 1-v2<40, 15-n (v 1-v 4) <40, and 15-n (v 1- (v 6+ v 7)/2-n (30) may be satisfied, where v1 is the abbe number of the first lens, v2 is the abbe number of the second lens, v4 is the abbe number of the fourth lens, v6 is the abbe number of the sixth lens, and v7 is the abbe number of the seventh lens.

In the optical imaging system, 0-f 1/f <1.4 may be satisfied, where f1 is the focal length of the first lens.

In the optical imaging system, it is possible to satisfy-3-n f2/f <0 where f2 is the focal length of the second lens.

In the optical imaging system, 1-n f3/f <6, where f3 is the focal length of the third lens, may be satisfied.

In the optical imaging system, 0-f/7/(10 × f) <5 may be satisfied, where f7 is a focal length of the seventh lens.

In the optical imaging system, it is possible to satisfy-3-Ap f8/f <0, where f8 is the focal length of the eighth lens.

In the optical imaging system, BFL/f <0.3 may be satisfied, where BFL is a distance from an image side surface of the eighth lens to the imaging surface on the optical axis.

In the optical imaging system, 70 ° < FOV x (IMG HT/f) <100 ° may be satisfied, where FOV is the field of view of the optical imaging system.

In the optical imaging system, it is possible to satisfy-0.2 plus SAG52/TTL <0 where SAG52 is the SAG value on the end of the effective diameter of the image-side surface of the fifth lens.

In the optical imaging system, it is possible to satisfy-0.2-plus-SAG 62/TTL <0, where SAG62 is an SAG value on an end of the effective diameter of the image-side surface of the sixth lens.

In the optical imaging system, it is possible to satisfy-0.3-woven SAG72/TTL <0, where SAG72 is an SAG value on an end of the effective diameter of the image-side surface of the seventh lens.

In the optical imaging system, it is possible to satisfy-0.3-woven SAG82/TTL <0, where SAG82 is an SAG value on an end of the effective diameter of the image-side surface of the eighth lens.

In the optical imaging system, one or both of 5< | Y72/Z72| <100 and 5< | Y82/Z82| <30 may be satisfied, where Y72 is a vertical height between the optical axis and the first inflection point of the image-side surface of the seventh lens, Y82 is a vertical height between the optical axis and the first inflection point of the image-side surface of the eighth lens, Z72 is an SAG value at the first inflection point of the image-side surface of the seventh lens, and Z82 is an SAG value at the first inflection point of the image-side surface of the eighth lens.

In the optical imaging system, the third lens has a positive refractive power, the fourth lens has a positive refractive power, the fifth lens has a negative refractive power, the seventh lens has a positive refractive power, and the eighth lens has a negative refractive power.

Other features and aspects will become apparent from the following detailed description, the appended claims, the drawings, and the following drawings.

Drawings

Fig. 1 is a diagram illustrating an optical imaging system according to a first exemplary embodiment of the present disclosure.

Fig. 2 is a graph showing aberration characteristics of the optical imaging system shown in fig. 1.

Fig. 3 is a diagram illustrating an optical imaging system according to a second exemplary embodiment of the present disclosure.

Fig. 4 is a graph showing aberration characteristics of the optical imaging system shown in fig. 3.

Fig. 5 is a diagram illustrating an optical imaging system according to a third exemplary embodiment of the present disclosure.

Fig. 6 is a graph showing aberration characteristics of the optical imaging system shown in fig. 5.

Fig. 7 is a diagram illustrating an optical imaging system according to a fourth exemplary embodiment of the present disclosure.

Fig. 8 is a graph showing aberration characteristics of the optical imaging system shown in fig. 7.

Fig. 9 is a diagram illustrating an optical imaging system according to a fifth exemplary embodiment of the present disclosure.

Fig. 10 is a graph showing aberration characteristics of the optical imaging system shown in fig. 9.

Fig. 11 is a diagram illustrating an optical imaging system according to a sixth exemplary embodiment of the present disclosure.

Fig. 12 is a graph showing aberration characteristics of the optical imaging system shown in fig. 11.

Fig. 13 is a diagram illustrating an optical imaging system according to a seventh exemplary embodiment of the present disclosure.

Fig. 14 is a graph showing aberration characteristics of the optical imaging system shown in fig. 13.

Fig. 15 is a diagram illustrating an optical imaging system according to an eighth exemplary embodiment of the present disclosure.

Fig. 16 is a graph showing aberration characteristics of the optical imaging system shown in fig. 15.

Fig. 17 is a diagram illustrating an optical imaging system according to a ninth exemplary embodiment of the present disclosure.

Fig. 18 is a graph showing aberration characteristics of the optical imaging system shown in fig. 17.

Fig. 19 is a diagram illustrating an optical imaging system according to a tenth exemplary embodiment of the present disclosure.

Fig. 20 is a graph showing aberration characteristics of the optical imaging system shown in fig. 19.

Like reference numerals refer to like elements throughout the drawings and the detailed description. The figures may not be drawn to scale and the relative sizes, proportions and depictions of the elements in the figures may be exaggerated for clarity, illustration and convenience.

Detailed Description

The following detailed description is provided to assist the reader in obtaining a thorough understanding of the methods, devices, and/or systems described herein. Various changes, modifications, and equivalents of the methods, devices, and/or systems described herein will, however, become apparent after understanding the disclosure of this application. For example, the order of operations described herein is merely an example, and is not limited to the order set forth herein, except as operations that must occur in a particular order, but may be varied as will be apparent upon understanding the disclosure of the present application. In addition, descriptions of features well known in the art may be omitted for greater clarity and conciseness.

The features described herein may be embodied in different forms and should not be construed as limited to the examples described herein. Rather, the examples described herein are provided merely to illustrate some of the many possible ways to implement the methods, apparatuses, and/or systems described herein that will be apparent after understanding the disclosure of the present application.

Throughout the specification, when an element such as a layer, region or substrate is described as being "on," "connected to" or "coupled to" another element, it can be directly on, "connected to" or "coupled to" the other element or one or more other elements may be present between the element and the other element. In contrast, when an element is referred to as being "directly on," "directly connected to" or "directly coupled to" another element, there are no other elements present between the element and the other element.

As used herein, the term "and/or" includes any one of the associated listed items as well as any combination of any two or more of the items.

Although terms such as "first", "second", and "third" may be used herein to describe various elements, components, regions, layers or sections, these elements, components, regions, layers or sections are not limited by these terms. Rather, these terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first member, first component, first region, first layer, or first portion referred to in these examples may also be referred to as a second member, second component, second region, second layer, or second portion without departing from the teachings of the examples described herein.

Spatially relative terms such as "over 8230; \8230; above", "under 8230; \8230; and" below "may be used herein for ease of description to describe the relationship of one element to another as shown in the figures. These spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "upper" relative to other elements would then be oriented "below" or "lower" relative to the other elements. Thus, the phrase "over" encompasses both orientations of "over" and "under", depending on the spatial orientation of the device, 8230 \8230 @. The device may also be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative terms used herein should be interpreted accordingly.

The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the disclosure. The articles "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprising," "including," and "having" specify the presence of stated features, integers, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, operations, elements, components, and/or groups thereof.

The features of the examples described herein may be combined in various ways that will be apparent after understanding the disclosure of this application. Further, while the examples described herein have a variety of configurations, other configurations are possible as will be apparent after understanding the disclosure of the present application.

In the drawings of the lenses shown, the thickness, size, and shape of the lenses are exaggerated to show examples, and the spherical or aspherical shape of the lenses shown in the drawings is an example, and the shape is not limited thereto.

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

Further, in each lens, the first surface refers to a surface (or an object side surface) adjacent to the object side, and the second surface refers to a surface (or an image side surface) adjacent to the image side. Further, in the exemplary embodiment, the unit of numerical values of the radius of curvature, thickness, distance, focal length, etc. of the lens is millimeters, and the unit of the field of view (FOV) is degrees.

Further, in the description of the shape of each lens, the concept in which one surface is convex means that the paraxial region of the surface is convex, the concept in which one surface is concave means that the paraxial region of the surface is concave, and the concept in which one surface is planar means that the paraxial region of the surface is planar. Therefore, even when it is described that one surface of the lens is convex, the edge portion of the lens may be concave. Similarly, even when it is described that one surface of the lens is concave, the edge portion of the lens may be convex. Further, when it is described that one surface of the lens is a plane, the edge portion of the lens may be convex or concave.

Paraxial region refers to a relatively narrow region adjacent to the optical axis.

The imaging plane may refer to a virtual plane on which a focal point may be formed by the optical imaging system. Alternatively, the imaging plane may refer to one surface of the image sensor on which light is received.

The optical imaging system in an exemplary embodiment may include eight lenses.

For example, the optical system in the 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, and an eighth lens, which are arranged in order from the object side. The first to eighth lenses may be spaced apart from each other by a predetermined distance along the optical axis.

However, the optical imaging system in the exemplary embodiment may include not only eight lenses but also other components if necessary.

For example, the optical imaging system may further include an image sensor for converting an incident image of the subject into an electrical signal.

Further, the optical imaging system may further include an infrared filter (hereinafter referred to as "filter") for blocking infrared rays. The filter may be disposed between the eighth lens and the image sensor.

Further, the optical imaging system may further include a diaphragm for adjusting the amount of light.

The first to eighth lenses included in the optical imaging system in the exemplary embodiment may be formed of a plastic material.

Further, at least one of the first lens to the eighth lens has an aspherical surface. Further, each of the first to eighth lenses may have at least one aspherical surface.

That is, at least one of the first and second surfaces of the first to eighth lenses may be aspherical. Here, aspherical surfaces of the first to eighth lenses are represented by equation 1.

Equation 1:

in equation 1, c is the curvature (inverse of the radius of curvature) of the lens, K is a conic constant, and Y is the distance from one point on the aspherical surface of the lens to the optical axis. Further, the constants a to P refer to aspherical coefficients. Z is a distance between one point on the aspherical surface of the lens and the vertex of the aspherical surface in the optical axis direction.

The optical imaging system in the exemplary embodiment may satisfy at least one of the following conditional expressions:

conditional expression 1 & lt 0 & ltf & lt 1.4 >

conditional expressions 2 25 were-v 2<40;

conditional expressions 3-15 were-t 1-v4<40;

conditional expression 4< -v 1- (v 6+ v 7)/2 < -30;

conditional expressions 5-3 were-woven fabric f2/f <0;

conditional expression 6-1-woven fabric f3/f <6;

conditional expressions 7 < -f7/(10 × f) <5;

conditional expressions 8-3 were-woven fabric f8/f <0;

conditional expression 9 BFL/f <0.3;

conditional expression 10 ° < FOV x (IMG HT/f) <100 °;

conditional expressions 11-0.2 are constructed by SAGS 52/TTL <0;

conditional expressions 12-0.2 are woven into SAGS 62/TTL <0;

conditional expressions 13-0.3 are woven and SAG72/TTL is less than 0;

conditional expressions 14-0.3 are woven and SAG82/TTL is less than 0;

conditional expression 15< | Y72/Z72| <100;

conditional expression 16 < | Y82/Z82| <30; and

conditional expression 17 (TTL/(2 × IMG HT)) × (TTL/f) <0.64.

In the conditional expression, f is a total focal length of the optical imaging system, f1 is a focal length of the first lens, f2 is a focal length of the second lens, f3 is a focal length of the third lens, f7 is a focal length of the seventh lens, and f8 is a focal length of the eighth lens.

v1 is the abbe number of the first lens, v2 is the abbe number of the second lens, v4 is the abbe number of the fourth lens, v6 is the abbe number of the sixth lens, and v7 is the abbe number of the seventh lens.

TTL is a distance from the object side surface of the first lens to the imaging surface on the optical axis, and BFL is a distance from the image side surface of the eighth lens to the imaging surface on the optical axis.

IMG HT is half the diagonal length of the imaging plane and FOV is the field of view of the optical imaging system.

SAG52 is the SAG value on the end of the effective diameter of the image-side face of the fifth lens, SAG62 is the SAG value on the end of the effective diameter of the image-side face of the sixth lens, SAG72 is the SAG value on the end of the effective diameter of the image-side face of the seventh lens, and SAG82 is the SAG value on the end of the effective diameter of the image-side face of the eighth lens.

When the SAG value has a negative value, the configuration indicates that the end of the effective diameter of the corresponding lens surface is disposed closer to the object side than the vertex of the corresponding lens surface.

When the SAG value has a positive value, the configuration indicates that the end of the effective diameter of the corresponding lens surface is disposed closer to the image side than the apex of the corresponding lens surface.

Y72 is a vertical height between the optical axis and the first inflection point of the image-side surface of the seventh lens, and Y82 is a vertical height between the optical axis and the first inflection point of the image-side surface of the eighth lens.

Z72 is the SAG value at the first inflection point of the image-side surface of the seventh lens, and Z82 is the SAG value at the first inflection point of the image-side surface of the eighth lens.

The first to eighth lenses included in the optical imaging system in the exemplary embodiment will be described.

The first lens may have a positive refractive power. Further, the first lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the first lens may be convex, and the second surface of the first lens may be concave.

At least one of the first surface and the second surface of the first lens may be aspheric. For example, both surfaces of the first lens may be aspherical.

The second lens may have a negative refractive power. Further, the second lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the second lens may be convex, and the second surface of the second lens may be concave.

At least one of the first surface and the second surface of the second lens may be aspheric. For example, both surfaces of the second lens may be aspherical.

The third lens may have a positive refractive power. Further, the third lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the third lens may be convex, and the second surface of the third lens may be concave.

At least one of the first surface and the second surface of the third lens may be aspherical. For example, both surfaces of the third lens may be aspherical.

The fourth lens may have a negative refractive power. Further, the fourth lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the fourth lens may be convex, and the second surface of the fourth lens may be concave.

Alternatively, both surfaces of the fourth lens may be convex. In more detail, the first surface and the second surface of the fourth lens may be convex.

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

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

Alternatively, the fifth lens may have a meniscus shape convex toward the image side. In more detail, the first surface of the fifth lens may be concave, and the second surface of the fifth lens may be convex.

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

The sixth lens may have a positive refractive power or a negative refractive power. Further, the sixth lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the sixth lens may be convex in the paraxial region, and the second surface of the sixth lens may be concave in the paraxial region.

At least one of the first surface and the second surface of the sixth lens may be aspheric. For example, both surfaces of the sixth lens may be aspherical.

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

The seventh lens may have a positive refractive power. Further, the seventh lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the seventh lens may be convex in the paraxial region, and the second surface of the seventh lens may be concave in the paraxial region.

Both surfaces of the seventh lens may be convex. In more detail, the first surface and the second surface of the seventh lens may be convex.

At least one of the first surface and the second surface of the seventh lens may be aspheric. For example, both surfaces of the seventh lens may be aspherical.

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

The eighth lens may have a negative refractive power. Further, the eighth lens may have a meniscus shape convex toward the object side. In more detail, the first surface of the eighth lens may be convex in the paraxial region, and the second surface of the eighth lens may be concave in the paraxial region.

Both surfaces of the eighth lens may be concave. In more detail, the first surface and the second surface of the eighth lens may be concave.

At least one of the first surface and the second surface of the eighth lens may be aspheric. For example, both surfaces of the eighth lens may be aspherical.

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

Each of the first to eighth lenses may be formed of a plastic material having optical characteristics different from those of adjacent lenses.

Meanwhile, at least three lenses among the first to eighth lenses may have a refractive index greater than 1.61. For example, the refractive indices of the second lens, the fifth lens, and the sixth lens may be greater than 1.61. Further, the refractive indices of the second lens, the fourth lens, and the sixth lens may be greater than 1.61.

An optical imaging system 100 according to a first exemplary embodiment will be described with reference to fig. 1 and 2.

The optical imaging system 100 in the first exemplary embodiment may include an optical system including a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, a seventh lens 170, and an eighth lens 180, and may further include an optical filter 190 and an image sensor IS.

The optical imaging system 100 in the first exemplary embodiment can form a focal point on the imaging plane 191. The imaging plane 191 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 191 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens are listed in table 1.

TABLE 1

The total focal length f of the optical imaging system 100 in the first exemplary embodiment may be 7.46mm, IMG HT may be 7.145mm, FOV may be 85.4, SAG52 may be-0.399mm, SAG62 may be-0.896mm, SAG72 may be-1.473 mm, and SAG82 may be-1.750 mm.

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

The second lens 120 may have a negative refractive power, a first surface of the second lens 120 may be convex, and a second surface of the second lens 120 may be concave.

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

The fourth lens 140 may have a negative refractive power, a first surface of the fourth lens 140 may be convex, and a second surface of the fourth lens 140 may be concave.

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

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

In addition, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 160 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region.

The seventh lens 170 may have a positive refractive power, a first surface of the seventh lens 170 may be convex, and a second surface of the seventh lens 170 may be concave.

Further, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the seventh lens 170 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The eighth lens 180 may have a negative refractive power, a first surface of the eighth lens 180 may be convex in a paraxial region, and a second surface of the eighth lens 180 may be concave in the paraxial region.

Further, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the eighth lens 180 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first through eighth lenses 110 through 180 may have an aspheric coefficient in table 2. For example, both the object-side and image-side surfaces of the first through eighth lenses 110 through 180 may be aspheric.

TABLE 2

Further, the optical imaging system configured as described above may have the aberration characteristics shown in fig. 2.

An optical imaging system 200 according to a second exemplary embodiment will be described with reference to fig. 3 and 4.

The optical imaging system 200 in the second exemplary embodiment may include an optical system including a first lens 210, a second lens 220, a third lens 230, a fourth lens 240, a fifth lens 250, a sixth lens 260, a seventh lens 270, and an eighth lens 280, and may further include a filter 290 and an image sensor IS.

The optical imaging system 200 in the second exemplary embodiment can form a focal point on the imaging surface 291. The imaging plane 291 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 291 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens are listed in table 3.

TABLE 3

The total focal length f of the optical imaging system 200 in the second exemplary embodiment may be 7.43mm, img HT may be 7.145mm, fov may be 85.6 °, SAG52 may be-0.464 mm, SAG62 may be-0.936 mm, SAG72 may be-1.547 mm, and SAG82 may be-1.750 mm.

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

The second lens 220 may have a negative refractive power, a first surface of the second lens 220 may be convex, and a second surface of the second lens 220 may be concave.

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

Fourth lens 240 may have a negative refractive power, a first surface of fourth lens 240 may be convex, and a second surface of fourth lens 240 may be concave.

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

Sixth lens 260 may have positive refractive power, a first surface of sixth lens 260 may be convex in a paraxial region, and a second surface of sixth lens 260 may be concave in the paraxial region.

In addition, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 260 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The seventh lens 270 may have a positive refractive power, a first surface of the seventh lens 270 may be convex, and a second surface of the seventh lens 270 may be concave.

Further, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the seventh lens 270 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The eighth lens 280 may have a negative refractive power, a first surface of the eighth lens 280 may be convex in a paraxial region, and a second surface of the eighth lens 280 may be concave in the paraxial region.

Further, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the eighth lens 280 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first to eighth lenses 210 to 280 may have an aspherical coefficient in table 4. For 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

Further, the optical imaging system configured as described above may have the aberration characteristics shown in fig. 4.

An optical imaging system 300 according to a third exemplary embodiment will be described with reference to fig. 5 and 6.

The optical imaging system 300 in the third exemplary embodiment may include an optical system including a first lens 310, a second lens 320, a third lens 330, a fourth lens 340, a fifth lens 350, a sixth lens 360, a seventh lens 370, and an eighth lens 380, and may further include an optical filter 390 and an image sensor IS.

The optical imaging system 300 in the third exemplary embodiment can form a focal point on the imaging plane 391. The imaging plane 391 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 391 may refer to a surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens are listed in table 5.

TABLE 5

The total focal length f of the optical imaging system 300 in the third exemplary embodiment may be 7.41mm, img HT may be 7.145mm, fov may be 85.8 °, SAG52 may be-0.484 mm, SAG62 may be-0.925mm, SAG72 may be-1.469 mm, and SAG82 may be-1.839 mm.

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

The second lens 320 may have a negative refractive power, a first surface of the second lens 320 may be convex, and a second surface of the second lens 320 may be concave.

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

Fourth lens 340 may have a positive refractive power, a first surface of fourth lens 340 may be convex, and a second surface of fourth lens 340 may be concave.

The fifth lens 350 may have a negative refractive power, a first surface of the fifth lens 350 may be convex, and a second surface of the fifth lens 350 may be concave.

The sixth lens 360 may have a negative refractive power, a first surface of the sixth lens 360 may be convex, and a second surface of the sixth lens 360 may be concave in the paraxial region.

Further, 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 convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 360 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The seventh lens 370 may have a positive refractive power, a first surface of the seventh lens 370 may be convex, and a second surface of the seventh lens 370 may be concave.

Further, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the seventh lens 370 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The eighth lens 380 may have a negative refractive power, a first surface of the eighth lens 380 may be convex, and a second surface of the eighth lens 380 may be concave.

In addition, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the eighth lens 380 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first through eighth lenses 310 through 380 may have an aspheric coefficient in table 6. For example, both the object side and the image side of the first through eighth lenses 310 through 380 may be aspheric.

TABLE 6

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 6.

An optical imaging system 400 according to a fourth exemplary embodiment will be described with reference to fig. 7 and 8.

The optical imaging system 400 in the fourth exemplary embodiment may include an optical system including a first lens 410, a second lens 420, a third lens 430, a fourth lens 440, a fifth lens 450, a sixth lens 460, a seventh lens 470, and an eighth lens 480, and may further include an optical filter 490 and an image sensor IS.

The optical imaging system 400 in the fourth exemplary embodiment can form a focal point on the imaging plane 491. The imaging plane 491 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 491 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens are listed in table 7.

TABLE 7

Noodle numbering	Marking	Radius of curvature	Thickness or distance	Refractive index	Abbe number	Focal length
							S1	First lens	2.566	0.819	1.544	56.0	7.07
S2		6.782	0.025
							S3	Second lens	4.841	0.220	1.680	18.2	-15.65
S4		3.279	0.189
							S5	Third lens	5.265	0.533	1.535	55.7	17.19
S6		11.819	0.248
							S7	Fourth lens	38.407	0.250	1.567	37.4	174.08
S8		62.461	0.474
							S9	Fifth lens element	190.903	0.341	1.680	18.2	-39.17
S10		23.634	0.457
							S11	Sixth lens element	21.495	0.340	1.635	24.0	-500.09
S12		20.020	0.553
							S13	Seventh lens element	4.815	0.474	1.567	37.4	15.07
S14		10.552	1.281
							S15	Eighth lens element	10.678	0.525	1.544	56.0	-5.42
S16		2.276	0.229
							S17	Light filter	Infinity(s)	0.110	1.517	64.2
S18		Infinity(s)	0.770
							S19	Image plane	Infinity(s)

The total focal length f of the optical imaging system 400 in the fourth exemplary embodiment may be 7.35mm, img HT may be 7.145mm, fov may be 86.2 °, SAG52 may be-0.488mm, SAG62 may be-0.927mm, SAG72 may be-1.477 mm, and SAG82 may be-1.850 mm.

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

The second lens 420 may have a negative refractive power, a first surface of the second lens 420 may be convex, and a second surface of the second lens 420 may be concave.

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

The fourth lens 440 may have a negative refractive power, a first surface of the fourth lens 440 may be convex, and a second surface of the fourth lens 440 may be concave.

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

The sixth lens 460 may have a negative refractive power, a first surface of the sixth lens 460 may be convex in a paraxial region, and a second surface of the sixth lens 460 may be concave in the paraxial region.

In addition, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 460 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The seventh lens 470 may have a positive refractive power, a first surface of the seventh lens 470 may be convex, and a second surface of the seventh lens 470 may be concave.

Further, 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 may be concave in a portion other than the paraxial region. The second surface of the seventh lens 470 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Eighth lens 480 may have a negative refractive power, a first surface of eighth lens 480 may be convex in a paraxial region, and a second surface of eighth lens 480 may be concave in a paraxial region.

In addition, 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 may be concave in a portion other than the paraxial region. The second surface of the eighth lens 480 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first through eighth lenses 410 through 480 may have an aspheric coefficient in table 8. For example, both the object side and the image side of the first through eighth lenses 410 through 480 may be aspheric.

TABLE 8

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 8.

An optical imaging system 500 according to a fifth exemplary embodiment will be described with reference to fig. 9 and 10.

The optical imaging system 500 in the fifth exemplary embodiment may include an optical system including a first lens 510, a second lens 520, a third lens 530, a fourth lens 540, a fifth lens 550, a sixth lens 560, a seventh lens 570, and an eighth lens 580, and may further include an optical filter 590 and an image sensor IS.

The optical imaging system 500 in the fifth exemplary embodiment may form a focal point on the imaging surface 591. The imaging surface 591 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging surface 591 may refer to the surface of the image sensor IS on which light IS received.

Table 9 lists the lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens.

TABLE 9

Noodle numbering	Marking	Radius of curvature	Thickness or distance	Refractive index	Abbe number	Focal length
							S1	First lens	2.626	0.873	1.544	56.0	6.51
S2		8.871	0.027
							S3	Second lens	4.527	0.220	1.680	18.2	-16.55
S4		3.176	0.259
							S5	Third lens	7.225	0.454	1.535	55.7	24.21
S6		15.902	0.460
							S7	Fourth lens	87.672	0.275	1.680	18.2	3953.4
S8		90.471	0.095
							S9	Fifth lens element	-9.099	0.305	1.567	37.4	-102.84
S10		-10.899	0.595
							S11	Sixth lens element	11.730	0.342	1.614	25.9	-28.86
S12		7.006	0.346
							S13	Seventh lens element	6.009	0.455	1.567	37.4	9.18
S14		-39.843	1.363
							S15	Eighth lens element	-34.685	0.515	1.535	55.7	-5.52
S16		3.258	0.300
							S17	Light filter	Infinity(s)	0.110	1.517	64.2
S18		Infinity(s)	0.826
							S19	Image plane	Infinity(s)

The total focal length f of the optical imaging system 500 in the fifth exemplary embodiment may be 7.24mm, img HT may be 7.145mm, fov may be 87.2 °, SAG52 may be-0.277 mm, SAG62 may be-0.794 mm, SAG72 may be-1.130 mm, and SAG82 may be-1.546 mm.

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

Second lens 520 may have a negative refractive power, a first surface of second lens 520 may be convex, and a second surface of second lens 520 may be concave.

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

The fourth lens 540 may have a positive refractive power, and a first surface of the fourth lens 540 may be convex and a second surface of the fourth lens 540 may be concave.

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

Sixth lens 560 may have a positive refractive power, a first surface of sixth lens 560 may be convex, and a second surface of sixth lens 560 may be concave.

In addition, 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 convex in the paraxial region, and may be concave in a portion other than the paraxial region. The second surface of the sixth lens 560 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

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

In addition, 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 may be concave in a portion other than the paraxial region. The second surface of the seventh lens 570 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region.

The eighth lens 580 may have a negative refractive power, and the first surface and the second surface of the eighth lens 580 may be concave in the paraxial region.

In addition, 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 may be concave in a portion other than the paraxial region. The second surface of the eighth lens 580 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first to eighth lenses 510 to 580 may have an aspherical coefficient in table 10. For example, both the object side and the image side of the first through eighth lenses 510 through 580 may be aspheric.

Watch 10

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 10.

An optical imaging system 600 according to a sixth exemplary embodiment will be described with reference to fig. 11 and 12.

The optical imaging system 600 in the sixth exemplary embodiment may include an optical system including a first lens 610, a second lens 620, a third lens 630, a fourth lens 640, a fifth lens 650, a sixth lens 660, a seventh lens 670, and an eighth lens 680, and may further include a filter 690 and an image sensor IS.

The optical imaging system 600 in the sixth exemplary embodiment can form a focal point on the imaging plane 691. The imaging plane 691 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 691 may refer to one surface of the image sensor IS on which light IS received.

Table 11 lists the lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens.

TABLE 11

The total focal length f of the optical imaging system 600 in the sixth exemplary embodiment may be 7.23mm, img HT may be 7.145mm, fov may be 87.2 °, SAG52 may be-0.322mm, SAG62 may be-0.770 mm, SAG72 may be-1.098 mm, and SAG82 may be-1.702 mm.

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

Second lens 620 may have a negative refractive power, a first surface of second lens 620 may be convex, and a second surface of second lens 620 may be concave.

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

The fourth lens 640 may have a positive refractive power, and the first and second surfaces of the fourth lens 640 may be convex.

The fifth lens 650 may have a negative refractive power, a first surface of the fifth lens 650 may be concave, and a second surface of the fifth lens 650 may be convex.

The sixth lens 660 may have a negative refractive power, a first surface of the sixth lens 660 may be convex, and a second surface of the sixth lens 660 may be concave.

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

Seventh lens 670 may have a positive refractive power, and a first surface and a second surface of seventh lens 670 may be convex in a paraxial region.

Further, 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 may be concave in a portion other than the paraxial region. Further, the second surface of the seventh lens 670 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region.

The eighth lens 680 may have a negative refractive power, and the first and second surfaces of the eighth lens 680 may be concave in the paraxial region.

In addition, 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 concave in the paraxial region, and may be convex in a portion other than the paraxial region. The second surface of the eighth lens 680 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first through eighth lenses 610 through 680 may have an aspheric coefficient in table 12. For example, both the object side surface and the image side surface of the first lens 610 to the eighth lens 680 may be aspheric.

TABLE 12

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 12.

An optical imaging system 700 according to a seventh exemplary embodiment will be described with reference to fig. 13 and 14.

The optical imaging system 700 in the seventh exemplary embodiment may include an optical system including a first lens 710, a second lens 720, a third lens 730, a fourth lens 740, a fifth lens 750, a sixth lens 760, a seventh lens 770, and an eighth lens 780, and may further include an optical filter 790 and an image sensor IS.

The optical imaging system 700 in the seventh exemplary embodiment may form a focal point on the imaging surface 791. The imaging plane 791 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 791 may refer to one surface of the image sensor IS on which light IS received.

Table 13 lists the lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number, and focal length) of each lens.

Watch 13

The total focal length f of the optical imaging system 700 in the seventh exemplary embodiment may be 7.23mm, img HT may be 7.145mm, fov may be 87.2 °, SAG52 may be-0.297 mm, SAG62 may be-0.758mm, SAG72 may be-1.071 mm, and SAG82 may be-1.716 mm.

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

The second lens 720 may have a negative refractive power, a first surface of the second lens 720 may be convex, and a second surface of the second lens 720 may be concave.

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

Fourth lens 740 may have a positive optical power, and a first surface of fourth lens 740 may be convex and a second surface of fourth lens 740 may be concave.

The fifth lens 750 may have a negative refractive power, a first surface of the fifth lens 750 may be concave, and a second surface of the fifth lens 750 may be convex.

Sixth lens 760 may have positive refractive power, and a first surface of sixth lens 760 may be convex and a second surface of sixth lens 760 may be concave.

Further, at least one inflection point may be formed on at least one of the first and second surfaces of the sixth lens 760. For example, the first surface of the sixth lens 760 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 760 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The seventh lens 770 may have a positive optical power, and the first and second surfaces of the seventh lens 770 may be convex in the paraxial region.

In addition, at least one inflection point may be formed on at least one of the first and second surfaces of the seventh lens 770. For example, the first surface of the seventh lens 770 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the seventh lens 770 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region.

The eighth lens 780 may have a negative refractive power, and the first surface and the second surface of the eighth lens 780 may be concave in the paraxial region.

Further, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 780. For example, the first surface of the eighth lens 780 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region. Further, the second surface of the eighth lens 780 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first through eighth lenses 710 through 780 may have aspheric coefficients in table 14. For example, both the object-side and image-side surfaces of the first through eighth lenses 710 through 780 may be aspheric.

TABLE 14

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 14.

An optical imaging system 800 according to an eighth exemplary embodiment will be described with reference to fig. 15 and 16.

The optical imaging system 800 in the eighth exemplary embodiment may include an optical system including a first lens 810, a second lens 820, a third lens 830, a fourth lens 840, a fifth lens 850, a sixth lens 860, a seventh lens 870, and an eighth lens 880, and may further include an optical filter 890 and an image sensor IS.

The optical imaging system 800 in the eighth exemplary embodiment can form a focal point on the imaging plane 891. Imaging plane 891 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 891 may refer to a surface of the image sensor IS on which light IS received.

Table 15 lists the lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens.

Watch 15

Noodle number	Marking	Radius of curvature	Thickness or distance	Refractive index	Abbe number	Focal length
							S1	First lens	2.588	0.808	1.544	56.0	7.08
S2		6.966	0.025
							S3	Second lens	5.731	0.220	1.680	18.2	-16.19
S4		3.727	0.177
							S5	Third lens	5.321	0.495	1.535	55.7	19.24
S6		10.608	0.275
							S7	Fourth lens	64.629	0.263	1.567	37.4	82.36
S8		-172.166	0.475
							S9	Fifth lens element	48.453	0.304	1.680	18.2	-32.82
S10		15.380	0.440
							S11	Sixth lens element	24.823	0.343	1.635	24.0	-455.55
S12		22.754	0.595
							S13	Seventh lens element	4.765	0.555	1.567	37.4	13.54
S14		11.898	1.237
							S15	Eighth lens element	10.129	0.450	1.544	56.0	-6.02
S16		2.444	0.272
							S17	Light filter	Infinity(s)	0.110	1.517	64.2
S18		Infinity(s)	0.795
							S19	Image plane	Infinity(s)

The total focal length f of the optical imaging system 800 in the eighth exemplary embodiment may be 7.24mm, img HT may be 7.145mm, fov may be 87.2 °, SAG52 may be-0.465 mm, SAG62 may be-0.907 mm, SAG72 may be-1.555 mm, and SAG82 may be-1.713 mm.

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

The second lens 820 may have a negative refractive power, a first surface of the second lens 820 may be convex, and a second surface of the second lens 820 may be concave.

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

The fourth lens 840 may have a positive refractive power, and the first surface and the second surface of the fourth lens 840 may be convex.

The fifth lens 850 may have a negative refractive power, a first surface of the fifth lens 850 may be convex, and a second surface of the fifth lens 850 may be concave.

Sixth lens 860 may have a negative refractive power, a first surface of sixth lens 860 may be convex in the paraxial region, and a second surface of sixth lens 860 may be concave in the paraxial region.

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

Seventh lens 870 may have a positive optical power, a first surface of seventh lens 870 may be convex, and a second surface of seventh lens 870 may be concave.

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

Eighth lens 880 may have a negative refractive power, a first surface of eighth lens 880 may be convex in a paraxial region, and a second surface of eighth lens 880 may be concave in a paraxial region.

In addition, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 880. For example, the first surface of the eighth lens 880 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the eighth lens 880 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first lens 810 to the eighth lens 880 may have an aspherical coefficient in table 16. For example, both the object-side and image-side surfaces of the first through eighth lenses 810 through 880 may be aspheric.

TABLE 16

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 16.

An optical imaging system 900 according to a ninth exemplary embodiment will be described with reference to fig. 17 and 18.

The optical imaging system 900 in the ninth exemplary embodiment may include an optical system including a first lens 910, a second lens 920, a third lens 930, a fourth lens 940, a fifth lens 950, a sixth lens 960, a seventh lens 970, and an eighth lens 980, and may further include a filter 990 and an image sensor IS.

The optical imaging system 900 in the ninth exemplary embodiment can form a focal point on the imaging surface 991. The imaging plane 991 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 991 may refer to one surface of the image sensor IS on which light IS received.

Table 17 lists the lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens.

TABLE 17

Noodle number	Marking	Radius of curvature	Thickness or distance	Refractive index	Abbe number	Focal length
							S1	First lens	2.574	0.790	1.544	56.0	7.09
S2		6.851	0.025
							S3	Second lens	5.666	0.220	1.680	18.2	-16.4
S4		3.714	0.178
							S5	Third lens	5.493	0.510	1.535	55.7	18.53
S6		11.862	0.277
							S7	Fourth lens	249.628	0.253	1.567	37.4	108.63
S8		-82.455	0.469
							S9	Fifth lens element	68.058	0.305	1.680	18.2	-31.39
S10		16.384	0.440
							S11	Sixth lens element	17.841	0.340	1.635	24.0	-6283.41
S12		17.630	0.614
							S13	Seventh lens element	4.769	0.549	1.567	37.4	13.41
S14		12.115	1.216
							S15	Eighth lens element	10.670	0.450	1.544	56.0	-6.1
S16		2.500	0.272
							S17	Light filter	Infinity(s)	0.110	1.517	64.2
S18		Infinity(s)	0.822
							S19	Image plane	Infinity(s)

The total focal length f of the optical imaging system 900 in the ninth exemplary embodiment may be 7.24mm, img HT may be 7.145mm, fov may be 87.2, SAG52 may be-0.464mm, SAG62 may be-0.903mm, SAG72 may be-1.562 mm, and SAG82 may be-1.769 mm.

In the ninth exemplary embodiment, the first lens 910 may have a positive refractive power, the first surface of the first lens 910 may be convex, and the second surface of the first lens 910 may be concave.

The second lens 920 may have a negative refractive power, a first surface of the second lens 920 may be convex, and a second surface of the second lens 920 may be concave.

The third lens 930 may have a positive refractive power, a first surface of the third lens 930 may be convex, and a second surface of the third lens 930 may be concave.

The fourth lens 940 may have a negative refractive power, and the first surface and the second surface of the fourth lens 940 may be convex.

The fifth lens 950 may have a negative refractive power, a first surface of the fifth lens 950 may be convex, and a second surface of the fifth lens 950 may be concave.

The sixth lens 960 may have a negative refractive power, a first surface of the sixth lens 960 may be convex, and a second surface of the sixth lens 960 may be concave.

In addition, at least one inflection point may be formed on at least one of the first and second surfaces of the sixth lens 960. For example, the first surface of the sixth lens 960 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the sixth lens 960 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Seventh lens 970 may have positive optical power, a first surface of seventh lens 970 may be convex, and a second surface of seventh lens 970 may be concave.

In addition, at least one inflection point may be formed on at least one of the first and second surfaces of the seventh lens 970. For example, the first surface of the seventh lens 970 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the seventh lens 970 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

The eighth lens 980 may have a negative refractive power, a first surface of the eighth lens 980 may be convex in a paraxial region, and a second surface of the eighth lens 980 may be concave in the paraxial region.

Further, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 980. For example, the first surface of the eighth lens 980 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. Further, the second surface of the eighth lens 980 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Each surface of the first lens 910 to the eighth lens 980 may have an aspherical coefficient in table 18. For example, both the object side and the image side of the first through eighth lenses 910 through 980 may be aspheric.

Watch 18

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 18.

An optical imaging system 1000 according to a tenth exemplary embodiment will be described with reference to fig. 19 and 20.

The optical imaging system 1000 in the tenth exemplary embodiment may include an optical system including a first lens 1010, a second lens 1020, a third lens 1030, a fourth lens 1040, a fifth lens 1050, a sixth lens 1060, a seventh lens 1070, and an eighth lens 1080, and may further include a filter 1090 and an image sensor IS.

The optical imaging system 1000 in the tenth exemplary embodiment can form a focal point on the imaging plane 1091. Imaging plane 1091 may refer to a surface on which a focal point may be formed by an optical imaging system. For example, the imaging plane 1091 may refer to a surface of the image sensor IS on which light IS received.

Table 19 lists the lens characteristics (radius of curvature, thickness of lens or distance between lenses, refractive index, abbe number and focal length) of each lens.

Watch 19

Noodle numbering	Marking	Radius of curvature	Thickness or distance	Refractive index	Abbe number	Focal length
							S1	First lens	2.572	0.784	1.544	56.0	7.1
S2		6.812	0.025
							S3	Second lens	5.290	0.220	1.680	18.2	-16.3
S4		3.535	0.188
							S5	Third lens	5.385	0.516	1.535	55.7	18.2
S6		11.583	0.267
							S7	Fourth lens	76.309	0.250	1.567	37.4	124.58
S8		-1041.521	0.461
							S9	Fifth lens element	83.881	0.317	1.680	18.2	-32.83
S10		17.793	0.445
							S11	Sixth lens element	16.668	0.340	1.635	24.0	2934.33
S12		16.683	0.600
							S13	Seventh lens element	4.783	0.551	1.567	37.4	13.81
S14		11.662	1.177
							S15	Eighth lens element	10.464	0.481	1.544	56.0	-6.16
S16		2.504	0.337
							S17	Light filter	Infinity(s)	0.110	1.517	64.2
S18		Infinity(s)	0.770
							S19	Image plane	Infinity(s)

The total focal length f of the optical imaging system 1000 in the tenth exemplary embodiment may be 7.24mm, img HT may be 7.145mm, fov may be 87.2 °, SAG52 may be-0.460mm, SAG62 may be-0.904 mm, SAG72 may be-1.550 mm, and SAG82 may be-1.762 mm.

In the tenth exemplary embodiment, the first lens 1010 may have a positive refractive power, the first surface of the first lens 1010 may be convex, and the second surface of the first lens 1010 may be concave.

The second lens 1020 may have a negative refractive power, a first surface of the second lens 1020 may be convex, and a second surface of the second lens 1020 may be concave.

Third lens 1030 may have a positive refractive power, a first surface of third lens 1030 may be convex, and a second surface of third lens 1030 may be concave.

Fourth lens 1040 may have a positive optical power, and the first and second surfaces of fourth lens 1040 may be convex.

Fifth lens 1050 may have a negative refractive power, a first surface of fifth lens 1050 may be convex, and a second surface of fifth lens 1050 may be concave.

The sixth lens 1060 may have a positive refractive power, a first surface of the sixth lens 1060 may be convex, and a second surface of the sixth lens 1060 may be concave.

Further, at least one inflection point may be formed on at least one of the first and second surfaces of the sixth lens 1060. For example, the first surface of the sixth lens 1060 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. The second surface of the sixth lens 1060 may be concave in the paraxial region, and may be convex in a portion other than the paraxial region.

Seventh lens 1070 may have a positive refractive power, and a first surface of seventh lens 1070 may be convex and a second surface of seventh lens 1070 may be concave.

In addition, at least one inflection point may be formed on at least one of the first and second surfaces of seventh lens 1070. For example, a first surface of seventh lens 1070 may be convex in the paraxial region and may be concave in portions other than the paraxial region. A second surface of seventh lens 1070 may be concave in the paraxial region and may be convex in a portion other than the paraxial region.

The eighth lens 1080 may have a negative refractive power, and a first surface of the eighth lens 1080 may be convex in a paraxial region and a second surface of the eighth lens 1080 may be concave in the paraxial region.

Further, at least one inflection point may be formed on at least one of the first and second surfaces of the eighth lens 1080. For example, the first surface of the eighth lens 1080 may be convex in the paraxial region, and may be concave in a portion other than the paraxial region. The second surface of the eighth lens 1080 may be concave in the paraxial region and may be convex in a portion other than the paraxial region.

Each surface of the first lens 1010 to the eighth lens 1080 may have an aspherical coefficient in table 20. For example, both the object-side and image-side surfaces of the first lens 1010 through the eighth lens 1080 may be aspheric.

Watch 20

Further, the optical imaging system configured as described above may have aberration characteristics shown in fig. 20.

According to the above-described exemplary embodiments, the optical imaging system can have a reduced size while achieving high resolution.

While the present disclosure includes specific examples, it will be apparent, after understanding the disclosure of the present application, that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only and not for purposes of limitation. The description of features or aspects in each example should be considered applicable to similar features or aspects in other examples. Suitable results may still be achieved if the described techniques are performed in a different order and/or if components in the described systems, architectures, devices, or circuits are combined in a different manner and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the present disclosure is defined not by the specific embodiments but by the claims and their equivalents, and all modifications within the scope of the claims and their equivalents should be understood as being included in the present disclosure.

Claims

1. An optical imaging system comprising:

a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in this order from an object side,

wherein the first lens has a positive refractive power and the second lens has a negative refractive power,

at least three lenses of the first to eighth lenses each have a refractive index of 1.61 or more,

satisfies (TTL/(2 × IMG HT)) × (TTL/f) <0.64, where TTL is a distance from an object side surface of the first lens to an imaging plane on an optical axis, IMG HT is a half of a diagonal length of the imaging plane, and f is a total focal length of the optical imaging system, and

the optical imaging system includes a total of eight lenses.

2. The optical imaging system of claim 1,

wherein the second lens has a refractive index of 1.61 or more, an

Wherein, among the at least three lenses having refractive indices of 1.61 or more, an absolute value of a focal length of a second lens of the at least three lenses is smallest.

3. The optical imaging system of claim 1,

wherein any one or any combination of any two or more of 25-v 1-v2<40, 15-v 1-v4<40 and 15-v 1- (v 6+ v 7)/2-woven 30 is satisfied, wherein v1 is the abbe number of the first lens, v2 is the abbe number of the second lens, v4 is the abbe number of the fourth lens, v6 is the abbe number of the sixth lens, and v7 is the abbe number of the seventh lens.

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

5. The optical imaging system of claim 1, wherein-3 < -f 2/f <0 is satisfied, wherein f2 is a focal length of the second lens.

6. The optical imaging system of claim 1, wherein 1< -f3/f <6 is satisfied, wherein f3 is a focal length of the third lens.

7. The optical imaging system according to claim 1, wherein 0< -f7/(10 xf) <5 is satisfied, where f7 is a focal length of the seventh lens.

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

9. The optical imaging system of claim 1,

wherein BFL/f <0.3,

and BFL is the distance from the image side surface of the eighth lens to the imaging surface on the optical axis.

10. The optical imaging system of claim 1, wherein 70 ° < FOV x (IMG HT/f) <100 ° is satisfied, wherein FOV is a field of view of the optical imaging system.

11. The optical imaging system of claim 1, wherein-0.2 ± SAG52/TTL <0 is satisfied, wherein SAG52 is an SAG value on an end of an effective diameter of an image-side surface of the fifth lens.

12. The optical imaging system of claim 1, wherein-0.2 ± SAG62/TTL <0 is satisfied, wherein SAG62 is an SAG value on an end of the effective diameter of the image-side surface of the sixth lens.

13. The optical imaging system of claim 1, wherein-0.3 ± SAG72/TTL <0 is satisfied, wherein SAG72 is an SAG value on an end of an effective diameter of an image-side surface of the seventh lens.

14. The optical imaging system of claim 1, wherein-0.3 < -SAG 82/TTL <0 is satisfied, wherein SAG82 is an SAG value on an end of the effective diameter of the image-side surface of the eighth lens.

15. The optical imaging system of claim 1,

wherein one or both of 5< | Y72/Z72| <100 and 5< | Y82/Z82| <30 are satisfied, wherein Y72 is a vertical height between the optical axis and the first inflection point of the image-side surface of the seventh lens, Y82 is a vertical height between the optical axis and the first inflection point of the image-side surface of the eighth lens, Z72 is an SAG value at the first inflection point of the image-side surface of the seventh lens, and Z82 is an SAG value at the first inflection point of the image-side surface of the eighth lens.

16. The optical imaging system of claim 1, wherein the third lens has a positive optical power, the fourth lens has a positive optical power, the fifth lens has a negative optical power, the seventh lens has a positive optical power, and the eighth lens has a negative optical power.