CN116953893A - Optical imaging system - Google Patents

Abstract

The present disclosure relates to an optical imaging system including 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 disposed in order from an object side, wherein the first lens has a positive refractive power, and the second lens has a negative refractive power. The refractive index of the second lens is greater than the refractive index of each of the first lens and the third lens. The optical imaging system satisfies TTL/(2×img HT) <0.6 and 0< f1/f <1.4, where TTL is a distance on the optical axis from the object side surface of the first lens to the imaging surface, IMG HT is half of a diagonal length of the imaging surface, f is a total focal length of the optical imaging system, and f1 is a focal length of the first lens.

Description

Optical imaging system

Cross Reference to Related Applications

The present application claims the benefit of priority from korean patent application No. 10-2022-015737 filed in the korean intellectual property office on day 9 and 14 of 2022, the entire disclosure of which is incorporated herein by reference for all purposes.

Technical Field

The following description relates to optical imaging systems.

Background

Recent portable terminals may include a camera provided with an optical imaging system including a plurality of lenses to perform video calling and capture images.

As functions of cameras in portable terminals are gradually increased, demands for cameras with high resolution for portable terminals are increasing.

In particular, recently, an image sensor having a high pixel count (e.g., 1300 tens of thousands to 1 million pixels) has been used in a camera of a portable terminal to achieve clearer image quality.

That is, the size of the image sensor has increased, and thus, the total length of the optical imaging system has also increased, so that there may be a problem in which the camera protrudes from the portable terminal.

Further, since the portable terminal is designed to have a smaller size, and a camera for the portable terminal is also required to have a reduced size, it is necessary to develop an optical imaging system having a smaller size and realizing high resolution.

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 one general aspect, an optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens disposed in order from an object side, wherein the first lens has a positive refractive power, and the second lens has a negative refractive power. The refractive index of the second lens is greater than the refractive index of each of the first lens and the third lens. The optical imaging system satisfies TTL/(2×img HT) <0.6 and 0< f1/f <1.4, where TTL is a distance on the optical axis from the object side surface of the first lens to the imaging surface, IMG HT is half of a diagonal length of the imaging surface, f is a total focal length of the optical imaging system, and f1 is a focal length of the first lens.

Among the first to eighth lenses, at least three lenses including the second lens may have a refractive index greater than 1.61, and an absolute value of a focal length of the second lens may be minimum among the at least three lenses having a refractive index greater than 1.61.

The optical imaging system may satisfy at least one of 25< v1-v2<45, v1-v4<45, and 10< v1- (v6+v7)/2 <30, 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.

The second, fifth and sixth lenses may have refractive indices greater than 1.61, and the optical imaging system may satisfy 60< v2+v5+v6<80, where v2 is the abbe number of the second lens, v5 is the abbe number of the fifth lens, and v6 is the abbe number of the sixth lens.

The fifth lens may have a negative refractive power, and each of the second and fifth lenses may have a refractive index greater than 1.66.

The optical imaging system may satisfy at least one of: -10< f2/f < -1;1< |f3/f|; and 3< |f4/f|, where f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f4 is the focal length of the fourth lens.

The optical imaging system may satisfy-0.6 < f1/f2<0.

The optical imaging system may satisfy-0.1 < f1/f3<1.

The optical imaging system may satisfy 0< |f2/f3| <1.

The optical imaging system may satisfy 1.5< f34/f <5.5, where f34 is the combined focal length of the third lens and the fourth lens.

The optical imaging system may satisfy at least one of: 3< |f5/f|;1< |f6/f|;0< f7/f <2; and-1 < f8/f <0, wherein 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.

The optical imaging system may satisfy TTL/f <1.3 and BFL/f <0.3, where BFL is a distance on the optical axis from the image side of the eighth lens to the imaging plane.

The optical imaging system may satisfy 0< D1/f <0.1, where D1 is a distance on the optical axis from the image side of the first lens to the object side of the second lens.

The optical imaging system may satisfy 0< D3/f <0.2, where D3 is a distance on the optical axis from the image side of the third lens to the object side of the fourth lens.

The optical imaging system may satisfy 70 ° < fov× (IMG HT/f), where FOV is the field of view of the optical imaging system.

The fourth lens may have a positive refractive power, the fifth lens may have a negative refractive power, the seventh lens may have a positive refractive power, and the eighth lens may have a negative refractive power.

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

Drawings

Fig. 1 is a diagram showing an optical imaging system according to a first example.

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

Fig. 3 is a diagram showing an optical imaging system according to a second example.

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

Fig. 5 is a diagram showing an optical imaging system according to a third example.

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

Fig. 7 is a diagram showing an optical imaging system according to a fourth example.

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

Fig. 9 is a diagram showing an optical imaging system according to a fifth example.

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

Fig. 11 is a diagram showing an optical imaging system according to a sixth example.

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

Fig. 13 is a diagram showing an optical imaging system according to a seventh example.

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

Fig. 15 is a diagram showing an optical imaging system according to an eighth example.

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

Like numbers refer to like elements throughout the drawings and detailed description. The drawings may not be to scale and the relative sizes, proportions and descriptions of elements in the drawings 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, apparatus, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, devices, and/or systems described herein will be apparent to those of ordinary skill in the art. For example, the order of operations described herein is merely an example and is not limited to the order set forth herein, but rather variations may be apparent to those of ordinary skill in the art, except that operations must occur in a certain order. In addition, descriptions of functions and structures that will be well known to those of ordinary skill in the art may be omitted for the sake of clarity and conciseness.

The features described herein may be implemented in different forms and are not to be construed as limited to the examples described herein. Rather, the examples described herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

It is noted herein that the term "may" is used with respect to an example or embodiment, for example with respect to what an example or embodiment may include or implement, meaning that there is at least one example or embodiment that includes or implements this feature, and that all examples and embodiments are not limited thereto.

Throughout the specification, when an element (such as a layer, region or substrate) is referred to as being "on," "connected to" or "coupled to" another element, it can be directly on, connected to or coupled to the other element or one or more other elements intervening therebetween. 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 intervening therebetween.

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

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 should not be 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 mentioned in examples described herein 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.

Spatially relative terms, such as "above," "upper," "lower," and the like, may be used herein for ease of description to describe one element's relationship to another element as illustrated in the figures. Such 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 another element would then be "below" or "lower" relative to the other element. Thus, the term "above" includes both above and below orientations, depending on the spatial orientation of the device. The device may also be oriented in other ways (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein 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 also include the plural forms unless the context clearly indicates otherwise. The terms "comprises," "comprising," and "having" specify the presence of stated features, amounts, operations, components, elements, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, amounts, operations, components, elements, and/or groups thereof.

The shapes of the illustrations as a result of manufacturing techniques and/or tolerances, are to be expected to vary. Accordingly, examples described herein are not limited to the particular shapes shown in the drawings, but include shape changes that occur during manufacture.

As will be apparent after an understanding of the present disclosure, the features of the examples described herein may be combined in various ways. Furthermore, while the examples described herein have a variety of configurations, other configurations are possible as will be apparent after an understanding of the present disclosure.

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

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

Further, in each lens, the first surface refers to a surface adjacent to the object side (or object side), and the second surface refers to a surface adjacent to the image side (or image side). Further, in each example, the units of values for radius of curvature, thickness, distance, focal length, etc. of the lens are millimeters, and the units of field of view (FOV) are degrees.

Further, in the description of the shape of each lens, the concept that one surface is convex indicates that the paraxial region of the surface is convex, the concept that one surface is concave indicates that the paraxial region of the surface is concave, and the concept that one surface is planar indicates 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. Furthermore, when it is described that one surface of the lens is planar, the edge portion of the lens may also 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 an 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 various examples may include eight lenses.

For example, the optical imaging system 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 disposed in order from the object side. The first to eighth lenses may be spaced apart from each other along the optical axis by a predetermined distance.

However, the optical imaging system may not simply include eight lenses, and may include other components if desired.

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

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

Furthermore, the optical imaging system may further comprise a diaphragm for adjusting the amount of incident light.

The first to eighth lenses included in the optical imaging system 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 surface and the second surface of the first to eighth lenses may be aspherical. Here, the aspherical surfaces of the first to eighth lenses are represented by formula 1.

[ 1]

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

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

[ conditional expression 1]0< f1/f <1.4

[ conditional expression 2]25< v1-v2<45

[ conditional expression 3] v1-v4<45

[ conditional expression 4]10< v1- (v6+v7)/2 <30

[ conditional expression 5-10 < f2/f < -1 ]

[ conditional expression 6]1< |f3/f| ]

[ conditional expression 7]3< |f4/f| ]

[ conditional expression 8]3< |f5/f| ]

[ conditional expression 9]1< |f6/f| ]

[ conditional expression 10]0< f7/f <2

[ conditional expression 11] -1< f8/f <0

[ conditional expression 12] TTL/f <1.3

[ conditional expression 13] -0.6< f1/f2<0

[ conditional expression 14] -0.1< f1/f3<1

[ conditional expression 15]0< |f2/f3| <1

[ conditional expression 16]1.5< f34/f <5.5

[ conditional expression 17] BFL/f <0.3

[ conditional expression 18]0< D1/f <0.1

[ conditional expression 19]0< D3/f <0.2

[ conditional expression 20] TTL/(2×IMG HT) <0.6

[ conditional expression 21]70 ° < FOV× (IMG HT/f)

[ conditional expression 22]60< v2+v5+v6<80

In the conditional expression, 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, f8 is the focal length of the eighth lens, and f34 is the combined focal length of the third lens and the fourth lens.

In the conditional expression, 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, v5 is the abbe number of the fifth lens, v6 is the abbe number of the sixth lens, and v7 is the abbe number of the seventh lens.

In the conditional expression, TTL is a distance on the optical axis from the object side surface of the first lens element to the imaging surface, BFL is a distance on the optical axis from the image side surface of the eighth lens element to the imaging surface, D1 is a distance on the optical axis between the image side surface of the first lens element and the object side surface of the second lens element, and D3 is a distance on the optical axis between the image side surface of the third lens element and the object side surface of the fourth lens element.

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

The first lens may have positive refractive power. Further, the first lens may have a meniscus shape protruding 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 aspherical. 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 protruding 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 aspherical. For example, both surfaces of the second lens may be aspherical.

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

Alternatively, the fourth lens may have a meniscus shape protruding 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 and second surfaces 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 protruding 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 protruding 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.

Alternatively, both surfaces of the fifth lens may be concave. In more detail, the first and second surfaces of the fifth lens may be concave.

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 positive or negative refractive power. Further, the sixth lens may have a meniscus shape protruding 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 aspherical. 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 concave in the paraxial region and may be convex in a portion other than the paraxial region.

The seventh lens may have positive refractive power. Further, the seventh lens may have a meniscus shape protruding 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.

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

At least one of the first surface and the second surface of the seventh lens may be aspherical. 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 convex in the paraxial region and may be concave 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 protruding 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.

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

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

Further, in the eighth lens, at least one inflection point may be formed on at least one of the first surface and the second surface. 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 third lenses may be configured to have a refractive index different from that of the adjacent lenses. For example, the first lens and the second lens have different refractive indices, and the second lens and the third lens may have different refractive indices. Further, among the first to third lenses, the refractive index of the second lens may be the largest.

Among the first to eighth lenses, at least three lenses including the second lens may have a refractive index greater than 1.61. For example, the refractive index of the second, fifth, and sixth lenses may be greater than 1.61. Further, the refractive index of the second lens and the fifth lens may be greater than 1.66.

Of the lenses having a refractive index greater than 1.61, the absolute value of the focal length of the second lens may be the lowest.

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

The optical imaging system 100 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 a filter 190 and an image sensor IS.

The optical imaging system 100 may form a focal point on the imaging plane 191. Imaging plane 191 may refer to a surface on which optical imaging system 100 may form a focal point. 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 lenses 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 may be 6.3132mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

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

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

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

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

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

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

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

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

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 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, the first surface of the eighth lens 180 may be convex in the paraxial region, and the 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 surface and the second surface 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 to eighth lenses 110 to 180 may have an aspherical coefficient as in table 2. For example, both the object side and the image side of the first to eighth lenses 110 to 180 may be aspherical.

TABLE 2

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Further, the optical imaging system 100 may have aberration characteristics shown in fig. 2.

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

The optical imaging system 200 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 may form a focal point on the imaging surface 291. Imaging face 291 may refer to a surface on which optical imaging system 200 may form a focal point. For example, the imaging surface 291 may refer to one surface of the image sensor IS on which light IS received.

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

TABLE 3

Face numbering	Element	Radius of curvature	Thickness or distance of	Refractive index	Abbe number	Focal length
							S1	First lens	2.331	0.962	1.544	56.0	5.1546
S2		11.551	0.024
							S3	Second lens	10.407	0.180	1.661	20.4	-12.6836
S4		4.639	0.388
							S5	Third lens	9.642	0.306	1.544	56.0	142.2645
S6		10.884	0.134
							S7	Fourth lens	-22.378	0.289	1.544	56.0	27.5069
S8		-9.031	0.247
							S9	Fifth lens	39.840	0.271	1.661	20.4	-25.5095
S10		11.907	0.359
							S11	Sixth lens	18.009	0.309	1.614	25.9	-93.5504
S12		13.652	0.527
							S13	Seventh lens	4.060	0.579	1.567	37.4	8.6488
S14		21.686	1.012
							S15	Eighth lens	14.304	0.430	1.535	55.7	-5.0177
S16		2.244	0.500
							S17	Optical filter	Infinity of infinity	0.210	1.517	64.2
S18		Infinity of infinity	0.363
							S19	Imaging surface	Infinity of infinity

The total focal length f of the optical imaging system 200 may be 6.3083mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

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

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

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

The fourth lens 240 may have a positive refractive power, the first surface of the fourth lens 240 may be concave, and the second surface of the fourth lens 240 may be convex.

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

The sixth lens 260 may have a negative refractive power, the first surface of the sixth lens 260 may be convex in the paraxial region, and the second surface of the 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 surface and the second surface 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, the first surface of the seventh lens 270 may be convex in the paraxial region, and the second surface of the seventh lens 270 may be concave in the paraxial region.

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface 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, the first surface of the eighth lens 280 may be convex in the paraxial region, and the 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 surface and the second surface 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 as in table 4. For example, both the object side and the image side of the first lens 210 to the eighth lens 280 may be aspherical.

TABLE 4

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Further, the optical imaging system 200 may have aberration characteristics shown in fig. 4.

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

The optical imaging system 300 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 a filter 390 and an image sensor IS.

The optical imaging system 300 may form a focal point on an imaging plane 391. Imaging plane 391 may refer to a surface on which optical imaging system 300 may form a focal point. For example, the imaging plane 391 may refer to one surface of the image sensor IS on which light IS received.

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

TABLE 5

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The total focal length f of the optical imaging system 300 may be 6.2878mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

In a third example, 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, the first surface of the second lens 320 may be convex, and the second surface of the second lens 320 may be concave.

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

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

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

The sixth lens 360 may have a negative refractive power, the first surface of the sixth lens 360 may be convex in the paraxial region, and the 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 surface and the second surface 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 in a paraxial region, and a second surface of the seventh lens 370 may be concave in a paraxial region.

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface 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. 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 in a paraxial region, and a second surface of the eighth lens 380 may be concave in a paraxial region.

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 380. For example, the first surface of eighth lens 380 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 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 to eighth lenses 310 to 380 may have an aspherical coefficient as in table 6. For example, both the object side and the image side of the first lens 310 to the eighth lens 380 may be aspherical.

TABLE 6

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Further, the optical imaging system 300 may have aberration characteristics shown in fig. 6.

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

The optical imaging system 400 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 a filter 490 and an image sensor IS.

The optical imaging system 400 may form a focal point on the imaging surface 491. Imaging surface 491 may refer to a surface upon which optical imaging system 400 may form a focal point. For example, the imaging surface 491 may refer to one surface of the image sensor IS on which light IS received.

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

TABLE 7

Face numbering	Element	Radius of curvature	Thickness or distance of	Refractive index	Abbe number	Focal length
							S1	First lens	2.356	0.922	1.544	56.0	5.7024
S2		8.333	0.054
							S3	Second lens	10.125	0.180	1.680	18.4	-16.4577
S4		5.311	0.368
							S5	Third lens	10.121	0.362	1.544	56.0	33.6493
S6		22.234	0.121
							S7	Fourth lens	-13.353	0.230	1.567	37.4	80.2515
S8		-10.404	0.299
							S9	Fifth lens	25.871	0.250	1.680	18.4	-29.9879
S10		11.443	0.328
							S11	Sixth lens	17.561	0.310	1.614	25.9	-68.2357
S12		12.326	0.487
							S13	Seventh lens	4.171	0.586	1.567	37.4	8.7035
S14		24.680	1.065
							S15	Eighth lens	13.691	0.431	1.535	55.7	-5.2190
S16		2.301	0.500
							S17	Optical filter	Infinity of infinity	0.210	1.517	64.2
S18		Infinity of infinity	0.388
							S19	Imaging surface	Infinity of infinity

The total focal length f of the optical imaging system 400 may be 6.338mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

In a fourth example, 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, the first surface of the second lens 420 may be convex, and the 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 positive refractive power, the first surface of the fourth lens 440 may be concave, and the second surface of the fourth lens 440 may be convex.

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

The sixth lens 460 may have a negative refractive power, the first surface of the sixth lens 460 may be convex in the paraxial region, and the 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 surface and the second surface 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. 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 in a paraxial region, and a second surface of the seventh lens 470 may be concave in the paraxial region.

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface of the seventh lens 470. For example, the first surface of the seventh lens 470 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.

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

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 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 to eighth lenses 410 to 480 may have an aspherical coefficient as in table 8. For example, both the object side and the image side of the first to eighth lenses 410 to 480 may be aspherical.

TABLE 8

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Further, the optical imaging system 400 may have aberration characteristics shown in fig. 8.

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

The optical imaging system 500 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 a filter 590 and an image sensor IS.

The optical imaging system 500 may form a focal point on an imaging plane 591. Imaging plane 591 may refer to a surface on which optical imaging system 500 may form a focal point. For example, the imaging plane 591 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lenses or distance between lenses, refractive index, abbe number, and focal length) of each lens are listed in table 9.

TABLE 9

The total focal length f of the optical imaging system 500 may be 6.4215mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

In a fifth example, 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.

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

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

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

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

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

Further, at least one inflection point may be formed on at least one of the first surface and the second surface of the sixth lens 560. For example, the first surface of the sixth lens 560 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 positive refractive power, and the first and second surfaces of the seventh lens 570 may be convex in a paraxial region.

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface of the seventh lens 570. For example, the first surface of the seventh lens 570 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 and second surfaces of the eighth lens 580 may be concave in a paraxial region.

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface of the eighth lens 580. For example, the first surface of the eighth lens 580 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 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 as in table 10. For example, both the object side and the image side of the first lens 510 to the eighth lens 580 may be aspherical.

TABLE 10

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Further, the optical imaging system 500 may have aberration characteristics shown in fig. 10.

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

The optical imaging system 600 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 may form a focal point on an imaging plane 691. Imaging plane 691 may refer to a surface on which optical imaging system 600 may form a focal point. For example, the imaging plane 691 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lenses or distance between lenses, refractive index, abbe number, and focal length) of each lens are listed in table 11.

TABLE 11

The total focal length f of the optical imaging system 600 may be 6.2999mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

In a sixth example, 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.

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

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

The fourth lens 640 may have a positive refractive power, the first surface of the fourth lens 640 may be concave, and the second surface 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 convex, and a second surface of the fifth lens 650 may be concave.

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

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface 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. 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.

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

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface 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. The second surface of the seventh lens 670 may be concave in the paraxial region and may be convex in a portion other than the paraxial region.

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

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface of the eighth lens 680. For example, the first surface of the eighth lens 680 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 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 to eighth lenses 610 to 680 may have an aspherical coefficient as in table 12. For example, both the object side and the image side of the first to eighth lenses 610 to 680 may be aspherical.

TABLE 12

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Further, the optical imaging system 600 may have aberration characteristics shown in fig. 12.

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

The optical imaging system 700 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 a filter 790 and an image sensor IS.

The optical imaging system 700 may form a focal point on the imaging plane 791. Imaging plane 791 may refer to a surface on which optical imaging system 700 may form a focal point. For example, the imaging surface 791 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lenses or distance between lenses, refractive index, abbe number, and focal length) of each lens are listed in table 13.

TABLE 13

The total focal length f of the optical imaging system 700 may be 6.27996 mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

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

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

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

The fourth lens 740 may have positive refractive power, and the first and second surfaces of the fourth lens 740 may be convex.

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

The sixth lens 760 may have a negative refractive power, the first surface of the sixth lens 760 may be convex in the paraxial region, and the second surface of the sixth lens 760 may be concave in the paraxial region.

In addition, at least one inflection point may be formed on at least one of the first surface and the second surface of the sixth lens 760. For example, the first surface of the sixth lens 760 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 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 refractive power, a first surface of the seventh lens 770 may be convex in a paraxial region, and a second surface of the seventh lens 770 may be concave in a paraxial region.

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 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. The second surface of the seventh lens 770 may be concave in the paraxial region and may be convex in a portion other than the paraxial region.

The eighth lens 780 may have a negative refractive power, the first surface of the eighth lens 780 may be convex in the paraxial region, 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 surface and the second surface of the eighth lens 780. For example, the first surface of the eighth lens 780 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 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 to eighth lenses 710 to 780 may have an aspherical coefficient as in table 14. For example, both the object side and the image side of the first lens 710 to the eighth lens 780 may be aspherical.

TABLE 14

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Further, the optical imaging system 700 may have aberration characteristics shown in fig. 14.

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

The optical imaging system 800 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 a filter 890 and an image sensor IS.

The optical imaging system 800 may form a focal point on the imaging surface 891. Imaging plane 891 may refer to a surface on which optical imaging system 800 may form a focal point. For example, the imaging surface 891 may refer to one surface of the image sensor IS on which light IS received.

The lens characteristics (radius of curvature, thickness of lenses or distance between lenses, refractive index, abbe number, and focal length) of each lens are listed in table 15.

TABLE 15

The total focal length f of the optical imaging system 800 may be 6.4236mm, the img HT may be 6.12mm, and the FOV may be 85.3 °.

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

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

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

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

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

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

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

The seventh lens 870 may have positive refractive power, and the first and second surfaces of the seventh lens 870 may be convex in the paraxial region.

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. The second 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.

The eighth lens 880 may have negative refractive power, and the first and second surfaces of the eighth lens 880 may be concave in the paraxial region.

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 880. For example, the first 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. 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 to eighth lenses 810 to 880 may have an aspherical coefficient as in table 16. For example, both the object side and the image side of the first lens 810 to the eighth lens 880 may be aspherical.

TABLE 16

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Further, the optical imaging system 800 may have aberration characteristics shown in fig. 16.

TABLE 17

Conditional expressions	Example 1	Example 2	Example 3	Example 4	Example 5	Example 6	Example 7	Example 8
									f1/f	0.804	0.817	0.877	0.900	1.033	0.825	0.811	1.039
v1-v2	35.590	35.590	37.590	37.590	37.590	37.590	35.590	37.590
									v1-v4	0	0	0	18.59	18.59	0	0	0
v1-(v6+v7)/2	24.320	24.320	24.320	24.320	25.340	24.320	24.320	24.320
									f2/f	-2.071	-2.011	-2.406	-2.597	-1.929	-2.181	-1.851	-2.004
|f3/f|	98.920	22.552	6.498	5.309	2.045	76.832	155.825	2.185
									|f4/f|	3.970	4.360	10.751	12.662	9.224	4.805	3.980	7.150
|f5/f|	4.279	4.044	4.758	4.731	3.612	15.353	6.217	3.439
									|f6/f|	6.038	14.830	26.917	10.766	10.963	2.823	5.888	10.737
f7/f	1.271	1.371	1.396	1.373	1.717	1.132	1.244	1.660
									f8/f	-0.817	-0.795	-0.788	-0.823	-0.806	-0.773	-0.767	-0.809
TTL/f	1.123	1.124	1.128	1.119	1.104	1.125	1.129	1.110
									f1/f2	-0.388	-0.406	-0.365	-0.346	-0.535	-0.378	-0.438	-0.519
f1/f3	-0.008	0.036	0.135	0.169	0.505	-0.011	-0.005	0.475
									|f2/f3|	0.021	0.090	0.373	0.493	0.951	0.029	0.012	0.964
f34/f	4.189	3.714	4.111	3.799	1.696	5.200	4.160	1.661
									BFL/f	0.165	0.170	0.172	0.173	0.158	0.162	0.163	0.175
D1/f	0.004	0.004	0.010	0.009	0.004	0.005	0.005	0.005
									D3/f	0.112	0.134	0.133	0.121	0.194	0.100	0.084	0.181
TTL/(2×IMG HT)	0.579	0.579	0.579	0.579	0.579	0.579	0.579	0.583
									FOV×(IMG HT/f)	82.690	82.754	83.024	82.366	81.295	82.864	83.132	81.268
v2+v5+v6	66.740	66.740	62.740	62.740	60.700	62.740	66.740	62.740

According to the above example, the optical imaging system can have a reduced size while achieving high resolution.

While the present disclosure includes specific examples, it will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered as illustrative only and not for the purpose of limitation. The descriptions of features or aspects in each example are considered to be applicable to similar features or aspects in other examples. Suitable results may also be obtained 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 are replaced or supplemented by other components or their equivalents. Therefore, the scope of the present disclosure is defined not by the detailed description but by the claims and their equivalents, and all changes within the scope of the claims and their equivalents are to be construed as being included in the present disclosure.

Claims (16)

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, which are sequentially disposed from the object side, wherein the first lens has a positive refractive power, the second lens has a negative refractive power,

wherein the refractive index of the second lens is greater than the refractive index of each of the first lens and the third lens,

the total of eight lenses having refractive power in the optical imaging system, and

wherein,,

TTL/(2×img HT) <0.6; and

0<f1/f<1.4，

where TTL is the distance on the optical axis from the object side surface of the first lens to the imaging surface, IMG HT is half the diagonal length of the imaging surface, f is the total focal length of the optical imaging system, and f1 is the focal length of the first lens.

2. The optical imaging system of claim 1,

wherein, among the first to eighth lenses, at least three lenses including the second lens have refractive indexes greater than 1.61, and

wherein, among the at least three lenses having a refractive index greater than 1.61, an absolute value of a focal length of the second lens is minimum.

3. The optical imaging system of claim 2, wherein,

at least one of 25< v1-v2<45, v1-v4<45, and 10< v1- (v6+v7)/2 <30 is 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.

4. The optical imaging system of claim 2,

wherein the second, fifth and sixth lenses have refractive indices of greater than 1.61, and

wherein 60< v2+v5+v6<80, wherein v2 is the abbe number of the second lens, v5 is the abbe number of the fifth lens, and v6 is the abbe number of the sixth lens.

5. The optical imaging system of claim 4,

wherein the fifth lens has a negative refractive power, and

wherein each of the second lens and the fifth lens has a refractive index greater than 1.66.

6. The optical imaging system of claim 1, wherein,

at least one of the following is satisfied:

-10<f2/f<-1；

1< |f3/f|; and

3<|f4/f|，

where f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f4 is the focal length of the fourth lens.

7. The optical imaging system of claim 6, wherein-0.6 < f1/f2<0.

8. The optical imaging system of claim 7, wherein-0.1 < f1/f3<1.

9. The optical imaging system of claim 8, wherein 0< |f2/f3| <1.

10. The optical imaging system of claim 8, wherein 1.5< f34/f <5.5, wherein f34 is a combined focal length of the third lens and the fourth lens.

11. The optical imaging system of claim 1, wherein,

at least one of the following is satisfied:

3<|f5/f|；

1<|f6/f|；

0< f7/f <2; and

-1<f8/f<0，

where 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.

12. The optical imaging system of claim 1, wherein TTL/f <1.3 and BFL/f <0.3, wherein BFL is a distance on the optical axis from an image side of the eighth lens to the imaging plane.

13. The optical imaging system of claim 1, wherein 0< D1/f <0.1, wherein D1 is a distance on the optical axis from an image side of the first lens to an object side of the second lens.

14. The optical imaging system of claim 13, wherein 0< D3/f <0.2, wherein D3 is a distance on the optical axis from an image side of the third lens to an object side of the fourth lens.

15. The optical imaging system of claim 1, wherein 70 ° < fov× (IMG HT/f), wherein FOV is the field of view of the optical imaging system.

16. The optical imaging system of claim 1, wherein 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.