OPTICAL IMAGING SYSTEM

Abstract

An optical imaging system includes a first lens having positive refractive power, a second lens having refractive power, a third lens having refractive power, a fourth lens having refractive power, a fifth lens having negative refractive power, wherein the first to fifth lenses are sequentially disposed from an object side, and a reflective member having a plurality of reflective surfaces to reflect the light refracted by the fifth lens multiple times, wherein 3<BFL/TL<7 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TL is a distance on an optical axis from an object-side surface of the first lens to the image-side surface of the fifth lens.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit under 35 USC 119(a) of Korean Patent Application Nos. 10-2022-0150877, filed on Nov. 11, 2022, and 10-2023-0034745, filed on Mar. 16, 2023, in the Korean Intellectual Property Office, the entire disclosures of which are incorporated herein by reference for all purposes.

BACKGROUND

1. Field

The present disclosure relates to an optical imaging system.

2. Description of the Background

A portable terminal may include a camera including an optical lens system comprised of a plurality of lenses to make video calls and capture images.

In addition, as the function performed by a camera in a portable terminal gradually increases, demand for a camera for a portable terminal having a high resolution may increase.

For example, an image sensor having a large number of pixels (e.g., 13 million to 100 million pixels, or the like) may be adopted in a camera for a portable terminal in order to implement clearer image quality.

In addition, since the portable terminal may be miniaturized and slimmed cameras for portable terminals may be required, development of an optical imaging system capable of implementing high resolution while being slim may be desired.

For example, in the case of a camera for a portable terminal having telephoto characteristics, the optical axes of a plurality of lenses may be disposed in parallel in a length direction or width direction of the portable terminal, and a reflective member may be disposed in front of the plurality of lenses, to prevent a total track length of the optical imaging system from affecting a thickness of the portable terminal.

However, in such a structure the thickness of the portable terminal may increase as the diameters of the plurality of lenses increase.

The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the disclosure.

SUMMARY

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 having positive refractive power, a second lens having refractive power, a third lens having refractive power, a fourth lens having refractive power, a fifth lens having negative refractive power, wherein the first to fifth lenses are sequentially disposed from an object side, and a reflective member having a plurality of reflective surfaces to reflect light refracted by the fifth lens multiple times, wherein 3<BFU/TL<7 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TL is a distance on an optical axis from an object-side surface of the first lens to the image-side surface of the fifth lens.

The conditional expression 1<TTL/BFL<2 may be satisfied, where TTL is a distance on an optical axis from an object-side surface of the first lens to the imaging plane.

The reflective member may include an incident surface into which light refracted by the fifth lens is incident, a first reflective surface for reflecting the light, a second reflective surface for reflecting the light reflected from the first reflective surface, and an emission surface from which light reflected from the second reflective surface is emitted, wherein PL/TTL<0.8 may be satisfied, where PL is a distance on an optical axis from the incident surface of the reflective member to the emission surface.

The conditional expression 1.3<f/f1<2.1 may be satisfied, where f is a total focal length of the first to fifth lenses, and f1 is a focal length of the first lens.

The conditional expression |f1/f2|<0.6 may be satisfied, where f2 is a focal length of the second lens.

The conditional expression 0<f1/|f23|<0.3 may be satisfied, where f23 is a combined focal length of the second lens and the third lens.

The conditional expression 1<TTL/f<1.5 may be satisfied.

The conditional expression 1.63<avg_n23<1.7 may be satisfied, where avg_n23 is an average value of a refractive index of the second lens and a refractive index of the third lens.

The conditional expression 2.7<Fno<4.6 may be satisfied, where Fno is an F-number of the optical imaging system.

The conditional expression 9<v1−(v2+v3)<37 may be satisfied, where v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, and v3 is an Abbe number of the third lens.

Each of the second lens and the third lens may have a refractive index greater than 1.61 and an Abbe number less than 30.

Any one of the second lens and the third lens may have a refractive index greater than 1.66.

A difference value of Abbe numbers between the first lens and the second lens may be greater than 29, and a difference value of Abbe numbers between the second lens and the third lens may be less than 7.

The first lens may be formed of a glass material having an Abbe number greater than 80, and the second to fifth lenses may be formed of a plastic material.

The first lens may be formed of a glass material having an Abbe number greater than 80, the second lens may be formed of a glass material having an Abbe number less than 30, and the third to fifth lenses may be formed of a plastic material.

The first lens may have a convex object-side surface and a concave image-side surface, the second lens may have a convex object-side surface and a concave image-side surface, and the third lens may have a concave image-side surface and the fourth lens may have a convex object-side surface.

In another general aspect, an optical imaging system, includes a first lens having positive refractive power, a second lens having refractive power, a third lens having refractive power, a fourth lens having refractive power, a fifth lens having negative refractive power, wherein the first to fifth lenses are sequentially disposed, and a reflective member having a plurality of reflective surfaces to reflect the light refracted by the fifth lens multiple times, wherein 2.7<Fno<4.6 is satisfied, where Fno is an F-number of the optical imaging system, and wherein 1<TTL/BFL<2 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TTL is a distance on an optical axis from an object-side surface of the first lens to the imaging plane.

The conditional expression PL/TTL<0.8 may be satisfied.

In another general aspect, an optical imaging system includes a first lens having positive refractive power, a convex object-side surface, and a concave image-side surface, a second lens having refractive power, a convex object-side surface, and a concave image-side surface, a third lens having refractive power and a concave image-side surface, a fourth lens having refractive power and a convex object-side surface, a fifth lens having negative refractive power and a concave image-side surface, wherein the first to fifth lenses are sequentially disposed, and a reflective member having a plurality of reflective surfaces to reflect the light refracted by the fifth lens multiple times, wherein 1.3<f/f1<2.1 is satisfied, where f is a total focal length of the first to fifth lenses, and f1 is a focal length of the first lens.

The conditional expression 3<BFL/TL<7 may be satisfied.

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

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a configuration diagram of an optical imaging system according to a first embodiment of the present disclosure.

FIG. 2 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 1.

FIG. 3 is a configuration diagram of an optical imaging system according to a second embodiment of the present disclosure.

FIG. 4 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 3.

FIG. 5 is a configuration diagram of an optical imaging system according to a third embodiment of the present disclosure.

FIG. 6 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 5.

FIG. 7 is a configuration diagram of an optical imaging system according to a fourth embodiment of the present disclosure.

FIG. 8 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 7.

FIG. 9 is a configuration diagram of an optical imaging system according to a fifth embodiment of the present disclosure.

FIG. 10 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 9.

FIG. 11 is a configuration diagram of an optical imaging system according to a sixth embodiment of the present disclosure.

FIG. 12 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 11.

FIG. 13 is a configuration diagram of an optical imaging system according to a seventh embodiment of the present disclosure.

FIG. 14 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 12.

FIG. 15 is a configuration diagram of an optical imaging system according to an eighth embodiment of the present disclosure.

FIG. 16 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 15.

FIG. 17 is a configuration diagram of an optical imaging system according to a ninth embodiment of the present disclosure.

FIG. 18 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 17.

FIG. 19 is a configuration diagram of an optical imaging system according to a tenth embodiment of the present disclosure.

FIG. 20 is a diagram illustrating aberration characteristics of the optical imaging system illustrated in FIG. 19.

FIG. 21 is a diagram of the optical imaging system illustrated in FIG. 1 viewed from another angle.

Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.

DETAILED DESCRIPTION

Hereinafter, while examples of the present disclosure will be described in detail with reference to the accompanying drawings, it is noted that examples are not limited to the same.

The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be apparent after an understanding of this disclosure. For example, the sequences of operations described herein are merely examples, and are not limited to those set forth herein, but may be changed as will be apparent after an understanding of this disclosure, with the exception of operations necessarily occurring in a certain order. Also, descriptions of features that are known in the art may be omitted for increased clarity and conciseness.

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

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 may be directly “on,” “connected to,” or “coupled to” the other element, or there may be one or more other elements intervening therebetween. In contrast, when an element is described as being “directly on,” “directly connected to,” or “directly coupled to” another element, there can be no other elements intervening therebetween.

As used herein, the term “and/or” includes any one and any combination of any two or more of the associated listed items; likewise, “at least one of” includes any one and any combination of any two or more of the associated listed items.

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

Spatially relative terms, such as “above,” “upper,” “below,” “lower,” and the like, may be used herein for ease of description to describe one element's relationship to another element as shown 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, an element described as being “above,” or “upper” relative to another element would then be “below,” or “lower” relative to the other element. Thus, the term “above” encompasses both the above and below orientations depending on the spatial orientation of the device. The device may also be oriented in other ways (rotated 90 degrees or at other orientations), and the spatially relative terms used herein are to be interpreted accordingly.

The terminology used herein is for describing various examples only, and is not to be used to limit 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 “comprises,” “includes,” and “has” specify the presence of stated features, numbers, operations, members, elements, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, numbers, operations, members, elements, and/or combinations thereof.

Due to manufacturing techniques and/or tolerances, variations of the shapes shown in the drawings may occur. Thus, the examples described herein are not limited to the specific shapes shown in the drawings, but include changes in shape that occur during manufacturing.

Herein, it is noted that use of the term “may” with respect to an example, for example, as to what an example may include or implement, means that at least one example exists in which such a feature is included or implemented while all examples are not limited thereto.

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

An aspect of the present disclosure may provide an optical imaging system capable of realizing a small size and high resolution.

In the following lens configuration diagrams, the thickness, size, and shape of the lenses may be illustrated in a somewhat exaggerated manner for explanatory purposes, and in particular, the spheric or aspherical shape presented in the lens configuration diagram is only presented as an example, and is not limited thereto.

An optical imaging system according to an embodiment of the present disclosure may include a plurality of lenses disposed in an optical axis. Each of the plurality of lenses may be disposed to be spaced apart from each other by a predetermined distance along the optical axis.

For example, the optical imaging system may include five lenses.

Among the lenses comprising the optical imaging system, a frontmost lens means a lens closest to an object side, and a rearmost lens means a lens closest to a reflective member.

For example, in an embodiment comprised of five lenses, the first lens refers to a lens closest to the object side, and the fifth lens refers to a lens closest to the reflective member.

In addition, in each lens, the first surface means a surface closest to an object side (or object-side surface), and the second surface means a surface closest to an image side (or image-side surface). In addition, in the present specification, all numerical values of a radius of curvature, thickness, distance, focal length, and the like, are represented in millimeters, and a unit of a field of view (FOV) is represented in degrees.

In addition, in the present specification, in an explanation of a shape of each lens, a convex shape on one surface may mean that a paraxial region of the surface is convex, and a concave shape on one surface may mean that a paraxial region of the surface is concave. Therefore, even when one surface of the lens is described as having a convex shape, an edge portion of the lens may be concave. Similarly, even when one surface of the lens is described as having a concave shape, an edge portion of the lens may be convex.

Meanwhile, the paraxial region refers to a very narrow region near and including an optical axis.

The imaging plane may refer to an imaginary plane on which a focus is formed by an optical imaging system. Alternatively, the imaging plane may refer to one surface of an image sensor through which light is received. The imaging plane may be a plane perpendicular to an optical axis of the optical imaging system.

An optical imaging system according to an embodiment of the present disclosure includes five lenses.

For example, an optical imaging system according to an embodiment of the present disclosure includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens sequentially disposed from an object side. Each of the first to fifth lenses is disposed to be spaced apart from each other by a predetermined distance along a first optical axis.

However, the optical imaging system according to an embodiment of the present disclosure is not comprised of only 5 lenses and may further include other components.

For example, the optical imaging system may further include a reflective member having a plurality of reflective surfaces for changing an optical path. Each reflective surface of the reflective member may be configured to change the optical path by 90° (degrees).

The reflective member may be disposed to the rear of the plurality of lenses. For example, the reflective member may be disposed between the fifth lens and an imaging plane (or image sensor). The reflective member may be a mirror or prism having a plurality of reflective surfaces.

Referring to FIG. 21, when the reflective member P is a prism, the prism includes an incident surface IP on which light is incident, a first reflective surface P1 for reflecting the light passing through the incident surface IP, a second reflective surface P2 for reflecting the light reflected by the reflective surface P1, and an emission surface EP from which light is emitted. For example, the prism may be configured to have a parallelogram shape when viewed from a side.

The light passing through the first to fifth lenses may pass through the incident surface of the reflective member, and the optical path may be changed by 90° on the first reflective surface, and the light path may be changed by 90° on the second reflective surface, and the light can pass through the emission surface of the reflective member and be incident on the imaging plane.

The optical imaging system may further include an image sensor for converting an incident image of a subject into an electrical signal.

In addition, the optical imaging system may further include an infrared cut-off filter (hereinafter, referred to as a ‘filter’) for blocking infrared rays. A filter is disposed between the reflective member and the imaging plane.

In addition, the optical imaging system may further include a stop for adjusting an amount of light.

An effective radius of the first lens may be larger than that of other lenses. That is, among the first to fifth lenses, the first lens may have the largest effective radius.

A portion of the plurality of lenses have at least one aspherical surface.

For example, at least one of the first and second surfaces of the fourth lens and the fifth lens may be aspherical. Here, the aspherical surface of each lens may be expressed by Equation 1.

$\begin{array}{cc}Z=\frac{{\mathrm{cY}}^{{ }^{}{ }^{}2}}{1+\sqrt{1-\left(1+K\right)c^{{ }^{}2}{Y}^{{ }^{}2}}}+{\mathrm{AY}}^{{ }^{}{ }^{}4}+{\mathrm{BY}}^{{ }^{}{ }^{}6}+{\mathrm{CY}}^{{ }^{}{ }^{}8}+{\mathrm{DY}}^{{ }^{}{ }^{}10}\dots & \mathrm{Equation}1\end{array}$

In Equation 1, c is a curvature of the lens (a reciprocal of a radius of curvature), K is a conic constant, and Y is a distance from an arbitrary point on an aspherical surface of the lens to an optical axis. In addition, constants A to D mean aspherical surface coefficients. Z(SAG) represents a distance in a direction of the optical axis between an arbitrary point on an aspherical surface of the lens and a vertex of the aspherical surface.

An optical imaging system according to an embodiment of the present disclosure may satisfy at least one of the following conditional expressions.

1.3<f/f1<2.1  (Conditional expression 1)

1<TTL/f<1.5  (Conditional expression 2)

PL/TTL<0.8  (Conditional expression 3)

0.6<PL/TTL<0.8  (Conditional expression 4)

|f1/f2|<0.6  (Conditional expression 5)

0<f1/|f23|<0.3  (Conditional expression 6)

1.63<avg_n23<1.7  (Conditional expression 7)

1<TTL/BFL<2  (Conditional expression 8)

3<BFL/TL<7  (Conditional expression 9)

2.7<Fno<4.6  (Conditional expression 10)

9<v1−(v2+v3)<37  (Conditional expression 11)

In the conditional expressions, 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, and f23 is a combined focal length of the first and second lenses.

TTL is a distance on an optical axis from an object-side surface of the first lens to an imaging plane, and PL is a distance on an optical axis from an incident surface to an emission surface of the reflective member.

BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TL is a distance on an optical axis from an object-side surface of the first lens to the image-side surface of the fifth lens.

Fno is a F-number of the optical imaging system, v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, and v3 is an Abbe number of the third lens.

In the present specification, TTL may mean a sum of a distance between an object-side surface of the first lens and a first reflective surface of the reflective member, a distance between a first reflective surface and a second reflective surface of the reflective member, and a distance between a second reflective surface of the reflective member and an imaging plane. BFL may mean a sum of a distance between an image-side surface of the fifth lens and a first reflective surface of the reflective member, a distance between a first reflective surface and a second reflective surface of the reflective member, and a distance between a second reflective surface of the reflective member and an imaging plane, and PL may mean a sum of a distance between an incident surface and a first reflective surface of the reflective member, a distance between a first reflective surface and a second reflective surface, and a distance between a second reflective surface and an emission surface.

In one or more examples, at least two lenses disposed in succession may be high refractive lenses. For example, each of the second lens and the third lens has a refractive index greater than 1.61. For example, any one of the at least two high refractive lenses disposed in succession has a refractive index greater than 1.66.

Each of the at least two lenses disposed in succession may have an Abbe number less than 30. For example, each of the second lens and the third lens may have an Abbe number less than 30.

In addition, the first to third lenses may be formed of materials having different optical characteristics. For example, the first lens may be a material having a relatively large Abbe number, and each of the second and third lenses may be formed of a material having a smaller Abbe number than that of the first lens. Therefore, chromatic aberration correction capability may be improved. A difference in Abbe numbers between the first lens and the second lens may be greater than 29. A difference in Abbe numbers between the second lens and the third lens may be less than 7.

In an embodiment, all of the first to fifth lenses may be formed of a plastic material.

In an embodiment, any one of the first to fifth lenses may be formed of a glass material, and the other lenses may be formed of a plastic material. For example, the first lens may be formed of a glass material, and the second to fifth lenses may be formed of a plastic material. In this case, the first lens has an Abbe number greater than 80.

In an embodiment, two of the first to fifth lenses may be formed of a glass material, and the remaining lenses may be formed of a plastic material. For example, the first lens and the second lens may be formed of a glass material, and the third to fifth lenses may be formed of a plastic material. In this case, the first lens may have an Abbe number greater than 80, and the second lens may have an Abbe number less than 30.

An optical imaging system according to an embodiment of the present disclosure may have characteristics of a telephoto lens having a relatively narrow field of view and a long focal length.

In addition, the optical imaging system according to an embodiment of the present disclosure may be configured so that a diagonal length of the imaging plane is relatively large. For example, an effective capturing region of an image sensor may be wide (i.e., a high-pixel image sensor).

Accordingly, when a captured image is cropped, images according to various magnifications may be captured without deterioration in image quality.

An optical imaging system according to a first embodiment of the present disclosure will be described with reference to FIGS. 1 and 2.

The optical imaging system according to the first embodiment of the present disclosure may include an optical system including a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, and a fifth lens 150, and may further include a filter 160 and an image sensor.

The optical imaging system according to the first embodiment of the present disclosure may form a focus on an imaging plane 170. The imaging plane 170 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 170 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 150 and the imaging plane 170, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 1.

TABLE 1
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	3.930	1.003	1.537	55.7	8.9164
S2		20.040	0.332
S3	Second lens	40.865	0.269	1.619	26.0	−16.8729
S4		8.300	0.258
S5	Third lens	9.699	0.300	1.678	19.2	16.2912
S6		78.969	0.100
S7	Fourth lens	8.867	0.358	1.537	55.7	17.4649
S8		162.616	0.090
S9	Fifth lens	57.552	0.300	1.619	26.0	−6.9516
S10		3.997	0.800
S11	Reflective	Infinity	2.500	1.518	64.2
S12	member	Infinity	11.500	1.518	64.2
S13		Infinity	3.000	1.518	64.2
S14		Infinity	0.300
S15	Filter	Infinity	0.210	1.518	64.2
S16		Infinity	0.501
S17	Imaging plane	Infinity

According to the first embodiment of the present disclosure, a total focal length f is 17.9357 mm, a combined focal length f23 of the first lens 110 and the second lens 120 is 355.675 mm, a field of view (FOV) is 18.93°, and an Fno is 4.5.

In the first embodiment of the present disclosure, the first lens 110 has positive refractive power, a first surface of the first lens 110 is convex, and a second surface of the first lens 110 is concave. The second lens 120 has negative refractive power, a first surface of the second lens 120 is convex, and a second surface of the second lens 120 is concave. The third lens 130 has positive refractive power, a first surface of the third lens 130 is convex, and a second surface of the third lens 130 is concave. The fourth lens 140 has positive refractive power, a first surface of the fourth lens 140 is convex, and a second surface of the fourth lens 140 is concave. The fifth lens 150 has negative refractive power, a first surface of the fifth lens 150 is convex, and a second surface of the fifth lens 150 is concave.

According to the first embodiment of the present disclosure, each surface of the fourth lens 140 and the fifth lens 150 has an aspherical surface coefficient as illustrated in Table 2. For example, the object-side surface of the fourth lens 140 and the image-side surface of the fifth lens 150 are aspherical.

	TABLE 2
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	−13.678	0.000	0.000	0.612
constant(K)
4th	0.000	1.1347E−02	0.000	0.000	−3.9868E−03
coefficient(A)
6th	0.000	2.4587E−03	0.000	0.000	−7.7041E−03
coefficient(B)
8th	0.000	−1.7393E−03	0.000	0.000	4.9189E−03
coefficient(C)
10th	0.000	7.3823E−04	0.000	0.000	2.1425E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 2.

An optical imaging system according to a second embodiment of the present disclosure will be described with reference to FIGS. 3 and 4.

The optical imaging system according to the second embodiment of the present disclosure may include an optical system including a first lens 210, a second lens 220, a third lens 230, a fourth lens 240, and a fifth lens 250, and may further include a filter 260 and an image sensor.

The optical imaging system according to the second embodiment of the present disclosure may form a focus on an imaging plane 270. The imaging plane 270 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 270 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 250 and the imaging plane 270, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 3.

TABLE 3
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	3.686	1.172	1.537	55.7	9.3169
S2		12.476	0.155
S3	Second lens	17.014	0.338	1.667	20.3	−35.947
S4		9.872	0.128
S5	Third lens	21.838	0.321	1.619	26.0	168.634
S6		27.457	0.120
S7	Fourth lens	18.128	0.320	1.537	55.7	−118.346
S8		14.015	0.120
S9	Fifth lens	32.554	0.320	1.619	26.0	−27.564
S10		11.156	1.000
S11	Reflective	Infinity	2.500	1.518	64.2
S12	member	Infinity	11.500	1.518	64.2
S13		Infinity	3.000	1.518	64.2
S14		Infinity	0.700
S15	Filter	Infinity	0.210	1.518	64.2
S16		Infinity	0.100
S17	Imaging plane	Infinity

According to the second embodiment of the present disclosure, a total focal length f is 17.5745 mm, a combined focal length f23 of the first lens 210 and the second lens 220 is −45.374 mm, a field of view (FOV) is 19.36°, and an Fno is 3.5.

In the second embodiment of the present disclosure, the first lens 210 has positive refractive power, a first surface of the first lens 210 is convex, and a second surface of the first lens 210 is concave. The second lens 220 has negative refractive power, a first surface of the second lens 220 is convex, and a second surface of the second lens 220 is concave. The third lens 230 has positive refractive power, a first surface of the third lens 230 is convex, and a second surface of the third lens 230 is concave. The fourth lens 240 has negative refractive power, a first surface of the fourth lens 240 is convex, and a second surface of the fourth lens 240 is concave. The fifth lens 250 has negative refractive power, a first surface of the fifth lens 250 is convex, and a second surface of the fifth lens 250 is concave.

According to the second embodiment of the present disclosure, each surface of the fourth lens 240 and the fifth lens 250 has an aspherical surface coefficient as illustrated in Table 4. For example, the object-side surface of the fourth lens 240 and the image-side surface of the fifth lens 250 are aspherical.

	TABLE 4
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	−1.097	0.000	0.000	7.245
constant(K)
4th	0.000	3.3029E−02	0.000	0.000	−2.4027E−02
coefficient(A)
6th	0.000	9.2861E−03	0.000	0.000	−7.5562E−03
coefficient(B)
8th	0.000	1.0741E−03	0.000	0.000	5.4256E−03
coefficient(C)
10th	0.000	−1.8004E−05	0.000	0.000	2.6493E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 4.

An optical imaging system according to a third embodiment of the present disclosure will be described with reference to FIGS. 5 and 6.

The optical imaging system according to the third embodiment of the present disclosure may include an optical system including a first lens 310, a second lens 320, a third lens 330, a fourth lens 340, and a fifth lens 350, and may further include a filter 360 and an image sensor.

The optical imaging system according to the third embodiment of the present disclosure may form a focus on an imaging plane 370. The imaging plane 370 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 370 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 350 and the imaging plane 370, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 5.

TABLE 5
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.514	1.846	1.537	55.7	13.5054
S2		20.372	0.196
S3	Second lens	28.610	0.511	1.667	20.3	−102.378
S4		20.017	0.187
S5	Third lens	83.829	0.526	1.619	26.0	−118.513
S6		39.038	0.180
S7	Fourth lens	23.641	0.679	1.537	55.7	31.9529
S8		−61.764	0.180
S9	Fifth lens	−31.393	0.420	1.570	37.3	−15.3871
S10		12.241	1.500
S11	Reflective	Infinity	3.750	1.518	64.2
S12	member	Infinity	17.250	1.518	64.2
S13		Infinity	4.500	1.518	64.2
S14		Infinity	1.050
S15	Filter	Infinity	0.210	1.518	64.2
S16		Infinity	0.100
S17	Imaging plane	Infinity

According to the third embodiment of the present disclosure, a total focal length f is 27.0295 mm, a combined focal length f23 of the first lens 310 and the second lens 320 is −54.912 mm, a field of view (FOV) is 18.87°, and an Fno is 3.7.

In the third embodiment of the present disclosure, the first lens 310 has positive refractive power, a first surface of the first lens 310 is convex, and a second surface of the first lens 310 is concave. The second lens 320 has negative refractive power, a first surface of the second lens 320 is convex, and a second surface of the second lens 320 is concave. The third lens 330 has negative refractive power, a first surface of the third lens 330 is convex, and a second surface of the third lens 330 is concave. The fourth lens 340 has positive refractive power, a first surface and a second surface of the fourth lens 340 are convex. The fifth lens 350 has negative refractive power, and a first surface and a second surface of the fifth lens 350 are concave.

According to the third embodiment of the present disclosure, each surface of the fourth lens 340 and the fifth lens 350 has an aspherical surface coefficient as illustrated in Table 6. For example, the object-side surface of the fourth lens 340 and the image-side surface of the fifth lens 350 are aspherical.

	TABLE 6
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	6.754	0.000	0.000	6.966
constant(K)
4th	0.000	4.6569E−02	0.000	0.000	−3.7082E−02
coefficient(A)
6th	0.000	1.5805E−02	0.000	0.000	−1.1260E−02
coefficient(B)
8th	0.000	1.9874E−03	0.000	0.000	8.0653E−03
coefficient(C)
10th	0.000	5.2633E−05	0.000	0.000	4.0137E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 6.

An optical imaging system according to a fourth embodiment of the present disclosure will be described with reference to FIGS. 7 and 8.

The optical imaging system according to the fourth embodiment may include an optical system including a first lens 410, a second lens 420, a third lens 430, a fourth lens 440, and a fifth lens 450, and may further include a filter 460 and an image sensor.

The optical imaging system according to the fourth embodiment of the present disclosure may form a focus on an imaging plane 470. The imaging plane 470 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 470 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 450 and the imaging plane 470, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 7.

TABLE 7
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.466	1.670	1.498	81.6	14.5328
S2		20.051	0.180
S3	Second lens	15.794	0.472	1.667	20.3	3187.65
S4		15.722	0.211
S5	Third lens	−560.724	0.467	1.619	26.0	−52.2352
S6		34.339	0.180
S7	Fourth lens	14.501	0.609	1.537	55.7	25.0889
S8		−184.993	0.180
S9	Fifth lens	−46.810	0.420	1.537	55.7	−15.6057
S10		10.229	1.500
S11	Reflective	Infinity	3.750	1.518	64.2
S12	member	Infinity	17.250	1.518	64.2
S13		Infinity	3.750	1.518	64.2
S14		Infinity	0.800
S15	Filter	Infinity	0.210	1.518	64.2
S16		Infinity	0.350
S17	Imaging plane	Infinity

According to the fourth embodiment of the present disclosure, a total focal length f is 25.7516 mm, a combined focal length f23 of the first lens 410 and the second lens 420 is −53.767 mm, a field of view (FOV) is 17.04°, and an Fno is 4.3.

In the fourth embodiment of the present disclosure, the first lens 410 has positive refractive power, a first surface of the first lens 410 is convex, and a second surface of the first lens 410 is concave. The second lens 420 has positive refractive power, a first surface of the second lens 420 is convex, and a second surface of the second lens 420 is concave. The third lens 430 has negative refractive power, a first surface and a second surface of the third lens 430 are concave. The fourth lens 440 has positive refractive power, a first surface and a second surface of the fourth lens 440 are convex. The fifth lens 450 has negative refractive power, and a first surface and a second surface of the fifth lens 450 are concave.

According to the fourth embodiment of the present disclosure, each surface of the fourth lens 440 and the fifth lens 450 has an aspherical surface coefficient as illustrated in Table 8. For example, the object-side surface of the fourth lens 440 and the image-side surface of the fifth lens 450 are aspherical.

	TABLE 8
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	7.001	0.000	0.000	6.169
constant(K)
4th	0.000	4.4983E−02	0.000	0.000	−4.2604E−02
coefficient(A)
6th	0.000	1.4691E−02	0.000	0.000	−1.0321E−02
coefficient(B)
8th	0.000	1.2177E−03	0.000	0.000	7.4719E−03
coefficient(C)
10th	0.000	−7.2996E−05	0.000	0.000	3.0641E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 8.

An optical imaging system according to a fifth embodiment of the present disclosure will be described with reference to FIGS. 9 and 10.

The optical imaging system according to the fifth embodiment of the present disclosure may include an optical system including a first lens 510, a second lens 520, a third lens 530, a fourth lens 540, and a fifth lens 550, and may further include a filter 560 and an image sensor.

The optical imaging system according to the fifth embodiment of the present disclosure may form a focus on an imaging plane 570. The imaging plane 570 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 570 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 550 and the imaging plane 570, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 9.

TABLE 9
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.579	1.803	1.498	81.6	14.0042
S2		24.811	0.333
S3	Second lens	19.088	0.509	1.669	20.3	10600.1
S4		18.935	0.270
S5	Third lens	897.471	0.420	1.621	26.0	−58.9185
S6		35.127	0.180
S7	Fourth lens	19.724	0.442	1.621	26.0	−2159
S8		19.271	0.180
S9	Fifth lens	31.068	0.420	1.537	55.7	−36.5762
S10		11.978	1.500
S11	Reflective	Infinity	3.750	1.519	64.2
S12	member	Infinity	17.250	1.519	64.2
S13		Infinity	3.750	1.519	64.2
S14		Infinity	0.800
S15	Filter	Infinity	0.210	1.519	64.2
S16		Infinity	0.167
S17	Imaging plane	Infinity

According to the fifth embodiment of the present disclosure, a total focal length f is 25.6925 mm, a combined focal length f23 of the first lens 510 and the second lens 520 is −59.894 mm, a field of view (FOV) is 19.84°, and an Fno is 3.6.

In the fifth embodiment of the present disclosure, the first lens 510 has positive refractive power, a first surface of the first lens 510 is convex, and a second surface of the first lens 510 is concave. The second lens 520 has positive refractive power, a first surface of the second lens 520 is convex, and a second surface of the second lens 520 is concave. The third lens 530 has negative refractive power, a first surface of the third lens 530 is convex, and a second surface of the third lens 530 is concave. The fourth lens 540 has negative refractive power, a first surface of the fourth lens 540 is convex, and a second surface of the fourth lens 540 are concave. The fifth lens 550 has negative refractive power, and a first surface of the fifth lens 550 is convex, and a second surface of the fifth lens 550 is concave.

According to the fifth embodiment of the present disclosure, each surface of the fourth lens 540 and the fifth lens 550 has an aspherical surface coefficient as illustrated in Table 10. For example, the object-side surface of the fourth lens 540 and the image-side surface of the fifth lens 550 are aspherical.

	TABLE 10
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	6.326	0.000	0.000	5.802
constant(K)
4th	0.000	4.5885E−02	0.000	0.000	−4.3638E−02
coefficient(A)
6th	0.000	1.2610E−02	0.000	0.000	−8.5422E−03
coefficient(B)
8th	0.000	−4.6826E−04	0.000	0.000	6.5223E−03
coefficient(C)
10th	0.000	−4.0156E−04	0.000	0.000	2.6836E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 10.

An optical imaging system according to a sixth embodiment of the present disclosure will be described with reference to FIGS. 11 and 12.

The optical imaging system according to the sixth embodiment of the present disclosure may include an optical system including a first lens 610, a second lens 620, a third lens 630, a fourth lens 640, and a fifth lens 650, and may further include a filter 660 and an image sensor.

The optical imaging system according to the sixth embodiment of the present disclosure may form a focus on an imaging plane 670. The imaging plane 670 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 670 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 650 and the imaging plane 670, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 11.

TABLE 11
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.585	1.799	1.498	81.6	14.0323
S2		24.751	0.351
S3	Second lens	18.266	0.445	1.669	20.3	−1306.62
S4		17.717	0.277
S5	Third lens	330.473	0.420	1.621	26.0	−62.7608
S6		34.826	0.180
S7	Fourth lens	19.286	0.446	1.621	26.0	−32472.8
S8		19.097	0.180
S9	Fifth lens	30.815	0.491	1.537	55.7	−36.056
S10		11.826	1.500
S11	Reflective	Infinity	3.750	1.519	64.2
S12	member	Infinity	17.250	1.519	64.2
S13		Infinity	3.750	1.519	64.2
S14		Infinity	0.500
S15	Filter	Infinity	0.210	1.519	64.2
S16		Infinity	0.433
S17	Imaging plane	Infinity

According to the sixth embodiment of the present disclosure, a total focal length f is 25.6924 mm, a combined focal length f23 of the first lens 610 and the second lens 620 is −60.422 mm, a field of view (FOV) is 19.84°, and an Fno is 3.6.

In the sixth embodiment of the present disclosure, the first lens 610 has positive refractive power, a first surface of the first lens 610 is convex, and a second surface of the first lens 610 is concave. The second lens 620 has negative refractive power, a first surface of the second lens 620 is convex, and a second surface of the second lens 620 is concave. The third lens 630 has negative refractive power, a first surface of the third lens 630 is convex, and a second surface of the third lens 630 is concave. The fourth lens 640 has negative refractive power, a first surface of the fourth lens 640 is convex, and a second surface of the fourth lens 640 is concave. The fifth lens 650 has negative refractive power, and a first surface of the fifth lens 650 is convex, and a second surface of the fifth lens 650 is concave.

According to the sixth embodiment of the present disclosure, each surface of the fourth lens 640 and the fifth lens 650 has an aspherical surface coefficient as illustrated in Table 12. For example, the object-side surface of the fourth lens 640 and the image-side surface of the fifth lens 650 are aspherical.

	TABLE 12
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	6.390	0.000	0.000	5.724
constant(K)
4th	0.000	4.6140E−02	0.000	0.000	−4.3353E−02
coefficient(A)
6th	0.000	1.2653E−02	0.000	0.000	−8.2880E−03
coefficient(B)
8th	0.000	−5.2151E−04	0.000	0.000	6.4432E−03
coefficient(C)
10th	0.000	−4.4183E−04	0.000	0.000	2.6185E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 12.

An optical imaging system according to a seventh embodiment of the present disclosure will be described with reference to FIGS. 13 and 14.

The optical imaging system according to the seventh embodiment of the present disclosure may include an optical system including a first lens 710, a second lens 720, a third lens 730, a fourth lens 740, and a fifth lens 750, and may further include a filter 760 and an image sensor.

The optical imaging system according to the seventh embodiment of the present disclosure may form a focus on an imaging plane 770. The imaging plane 770 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 770 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 750 and the imaging plane 770, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but it may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 13.

TABLE 13
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.709	1.537	1.498	81.6	17.7575
S2		14.640	0.100
S3	Second lens	9.649	0.690	1.723	29.5	49.0732
S4		12.856	0.445
S5	Third lens	43.942	0.446	1.621	26.0	−170.066
S6		30.904	0.180
S7	Fourth lens	21.488	0.441	1.537	55.7	413.944
S8		23.616	0.180
S9	Fifth lens	40.090	0.440	1.621	26.0	−19.9197
S10		9.409	1.500
S11	Reflective	Infinity	3.750	1.519	64.2
S12	member	Infinity	17.250	1.519	64.2
S13		Infinity	3.750	1.519	64.2
S14		Infinity	0.500
S15	Filter	Infinity	0.000	1.519	64.2
S16		Infinity	0.738
S17	Imaging plane	Infinity

According to the seventh embodiment of the present disclosure, a total focal length f is 26.3794 mm, a combined focal length f23 of the first lens 710 and the second lens 720 is 67.384 mm, a field of view (FOV) is 19.31°, and an Fno is 3.7.

In the seventh embodiment of the present disclosure, the first lens 710 has positive refractive power, a first surface of the first lens 710 is convex, and a second surface of the first lens 710 is concave. The second lens 720 has positive refractive power, a first surface of the second lens 720 is convex, and a second surface of the second lens 720 is concave. The third lens 730 has negative refractive power, a first surface of the third lens 730 is convex, and a second surface of the third lens 730 is concave. The fourth lens 740 has positive refractive power, a first surface of the fourth lens 740 is convex, and a second surface of the fourth lens 740 is concave. The fifth lens 750 has negative refractive power, and a first surface of the fifth lens 750 is convex, and a second surface of the fifth lens 750 is concave.

According to the seventh embodiment of the present disclosure, each surface of the fourth lens 740 and the fifth lens 750 has an aspherical surface coefficient as illustrated in Table 14. For example, the object-side surface of the fourth lens 740 and the image-side surface of the fifth lens 750 are aspherical.

	TABLE 14
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	−6.343	0.000	0.000	4.660
constant(K)
4th	0.000	5.3589E−02	0.000	0.000	−1.9858E−02
coefficient(A)
6th	0.000	1.8425E−02	0.000	0.000	−1.3145E−02
coefficient(B)
8th	0.000	1.8890E−03	0.000	0.000	7.5008E−03
coefficient(C)
10th	0.000	−5.6871E−05	0.000	0.000	3.8089E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 14.

An optical imaging system according to an eighth embodiment of the present disclosure will be described with reference to FIGS. 15 and 16.

The optical imaging system according to the eighth embodiment of the present disclosure may include an optical system including a first lens 810, a second lens 820, a third lens 830, a fourth lens 840, and a fifth lens 850, and may further include a filter 860 and an image sensor.

The optical imaging system according to the eighth embodiment of the present disclosure may form a focus on an imaging plane 870. The imaging plane 870 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 870 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 850 and the imaging plane 870, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but it may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 15.

TABLE 15
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.488	1.570	1.498	81.6	16.8224
S2		14.394	0.100
S3	Second lens	8.741	0.755	1.722	29.5	35.0739
S4		12.869	0.260
S5	Third lens	45.264	0.657	1.619	26.0	−70.5696
S6		22.111	0.180
S7	Fourth lens	14.461	0.540	1.537	55.7	57.5311
S8		26.852	0.180
S9	Fifth lens	51.513	0.500	1.619	26.0	−15.2207
S10		7.938	1.500
S11	Reflective	Infinity	3.750	1.518	64.2
S12	member	Infinity	11.250	1.518	64.2
S13		Infinity	3.750	1.518	64.2
S14		Infinity	0.500
S15	Filter	Infinity	0.000	1.518	64.2
S16		Infinity	0.738
S17	Imaging plane	Infinity

According to the eighth embodiment of the present disclosure, a total focal length f is 22.1449 mm, a combined focal length f23 of the first lens 810 and the second lens 820 is 65.433 mm, a field of view (FOV) is 22.80°, and an Fno is 3.

In the eighth embodiment of the present disclosure, the first lens 810 has positive refractive power, a first surface of the first lens 810 is convex, and a second surface of the first lens 810 is concave. The second lens 820 has positive refractive power, a first surface of the second lens 820 is convex, and a second surface of the second lens 820 is concave. The third lens 830 has negative refractive power, a first surface of the third lens 830 is convex, and a second surface of the third lens 830 is concave. The fourth lens 840 has positive refractive power, a first surface of the fourth lens 840 is convex, and a second surface of the fourth lens 840 is concave. The fifth lens 850 has negative refractive power, and a first surface of the fifth lens 850 is convex, and a second surface of the fifth lens 850 is concave.

According to the eighth embodiment of the present disclosure, each surface of the fourth lens 840 and the fifth lens 850 has an aspherical surface coefficient as illustrated in Table 16. For example, the object-side surface of the fourth lens 840 and the image-side surface of the fifth lens 850 are aspherical.

	TABLE 16
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	−7.101	0.000	0.000	3.470
constant(K)
4th	0.000	5.2727E−02	0.000	0.000	−2.3865E−02
coefficient(A)
6th	0.000	1.9801E−02	0.000	0.000	−1.3209E−02
coefficient(B)
8th	0.000	8.9334E−04	0.000	0.000	7.0935E−03
coefficient(C)
10th	0.000	−1.8426E−04	0.000	0.000	2.3433E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 16.

An optical imaging system according to a ninth embodiment of the present disclosure will be described with reference to FIGS. 17 and 18.

The optical imaging system according to the ninth embodiment of the present disclosure may include an optical system including a first lens 910, a second lens 920, a third lens 930, a fourth lens 940, and a fifth lens 950, and may further include a filter 960 and an image sensor.

The optical imaging system according to the ninth embodiment of the present disclosure may form a focus on an imaging plane 970. The imaging plane 970 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 970 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 950 and the imaging plane 970, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 17.

TABLE 17
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.309	1.747	1.498	81.6	15.4335
S2		15.278	0.100
S3	Second lens	8.923	0.726	1.677	19.2	34.1972
S4		14.044	0.251
S5	Third lens	52.808	0.620	1.619	26.0	−45.0663
S6		18.177	0.180
S7	Fourth lens	11.238	0.856	1.537	55.7	15.0786
S8		−28.120	0.180
S9	Fifth lens	−23.736	0.500	1.619	26.0	−8.3865
S10		6.702	1.500
S11	Reflective	Infinity	2.500	1.518	64.2
S12	member	Infinity	11.250	1.518	64.2
S13		Infinity	2.500	1.518	64.2
S14		Infinity	0.500
S15	Filter	Infinity	0.000	1.518	64.2
S16		Infinity	0.400
S17	Imaging plane	Infinity

According to the ninth embodiment of the present disclosure, a total focal length f is 20.6629 mm, a combined focal length f23 of the first lens 910 and the second lens 920 is 120.107 mm, a field of view (FOV) is 24.24°, and an Fno is 2.9.

In the ninth embodiment of the present disclosure, the first lens 910 has positive refractive power, a first surface of the first lens 910 is convex, and a second surface of the first lens 910 is concave. The second lens 920 has positive refractive power, a first surface of the second lens 920 is convex, and a second surface of the second lens 920 is concave. The third lens 930 has negative refractive power, a first surface of the third lens 930 is convex, and a second surface of the third lens 930 is concave. The fourth lens 940 has positive refractive power, and a first surface and a second surface of the fourth lens 940 are convex. The fifth lens 950 has negative refractive power, and a first surface and a second surface of the fifth lens 950 are concave.

According to the ninth embodiment of the present disclosure, each surface of the fourth lens 940 and the fifth lens 950 has an aspherical surface coefficient as illustrated in Table 18. For example, the object-side surface of the fourth lens 940 and the image-side surface of the fifth lens 950 are aspherical.

	TABLE 18
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	−7.041	0.000	0.000	2.511
constant(K)
4th	0.000	5.7406E−02	0.000	0.000	−2.6976E−02
coefficient(A)
6th	0.000	2.7334E−02	0.000	0.000	−1.1861E−02
coefficient(B)
8th	0.000	2.3004E−03	0.000	0.000	6.1575E−03
coefficient(C)
10th	0.000	−2.3473E−04	0.000	0.000	6.7858E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 18.

An optical imaging system according to a tenth embodiment of the present disclosure will be described with reference to FIGS. 19 and 20.

The optical imaging system according to the tenth embodiment of the present disclosure may include an optical system including a first lens 1010, a second lens 1020, a third lens 1030, a fourth lens 1040, and a fifth lens 1050, and may further include a filter 1060 and an image sensor.

The optical imaging system according to the tenth embodiment of the present disclosure may form a focus on an imaging plane 1070. The imaging plane 1070 may refer to a surface on which a focus is formed by an optical imaging system. For example, the imaging plane 1070 may refer to one surface of an image sensor through which light is received.

The optical imaging system may further include a reflective member P disposed between the fifth lens 1050 and the imaging plane 1070, and having a plurality of reflective surfaces for changing an optical path. For example, the reflective member P includes a first reflective surface P1 and a second reflective surface P2. The reflective member P may be a prism, but it may also be provided as a mirror.

Lens characteristics of each lens (radius of curvature, thickness of lens or distance between lenses, refractive index, Abbe number, and focal length) are illustrated in Table 19.

TABLE 19
Surface		Radius of	Thickness or	Refractive	Abbe	Focal
No.	Reference	curvature	distance	index	number	length
S1	First lens	5.368	1.900	1.537	55.7	12.244
S2		25.735	0.100
S3	Second lens	12.497	0.722	1.677	19.2	47.6522
S4		19.924	0.170
S5	Third lens	−363.201	0.499	1.619	26.0	−31.8721
S6		20.882	0.180
S7	Fourth lens	13.689	0.717	1.537	55.7	15.9344
S8		−22.356	0.201
S9	Fifth lens	−17.746	0.908	1.619	26.0	−8.3985
S10		7.501	1.200
S11	Reflective	Infinity	2.500	1.518	64.2
S12	member	Infinity	11.250	1.518	64.2
S13		Infinity	2.500	1.518	64.2
S14		Infinity	0.500
S15	Filter	Infinity	0.000	1.518	64.2
S16		Infinity	0.400
S17	Imaging plane	Infinity

According to the tenth embodiment of the present disclosure, a total focal length f is 20.6295 mm, a combined focal length f23 of the first lens 1010 and the second lens 1020 is −106.897 mm, a field of view (FOV) is 24.71°, and an Fno is 2.8.

In the tenth embodiment of the present disclosure, the first lens 1010 has positive refractive power, a first surface of the first lens 1010 is convex, and a second surface of the first lens 1010 is concave. The second lens 1020 has positive refractive power, a first surface of the second lens 1020 is convex, and a second surface of the second lens 1020 is concave. The third lens 1030 has negative refractive power, and a first surface and a second surface of the third lens 1030 are concave. The fourth lens 1040 has positive refractive power, and a first surface and a second surface of the fourth lens 1040 are convex. The fifth lens 1050 has negative refractive power, and a first surface and a second surface of the fifth lens 1050 are concave.

According to the tenth embodiment of the present disclosure, each surface of the fourth lens 1040 and the fifth lens 1050 has an aspherical surface coefficient as illustrated in Table 20. For example, the object-side surface of the fourth lens 1040 and the image-side surface of the fifth lens 1050 are aspherical.

	TABLE 20
		S1	S2	S3	S4	S5
	Conic	0.000	0.000	0.000	0.000	0.000
	constant(K)
	4th	0.000	0.000	0.000	0.000	0.000
	coefficient(A)
	6th	0.000	0.000	0.000	0.000	0.000
	coefficient(B)
	8th	0.000	0.000	0.000	0.000	0.000
	coefficient(C)
	10th	0.000	0.000	0.000	0.000	0.000
	coefficient(D)
	S6	S7	S8	S9	S10
Conic	0.000	−7.474	0.000	0.000	2.922
constant(K)
4th	0.000	5.4355E−02	0.000	0.000	−5.5165E−02
coefficient(A)
6th	0.000	2.5566E−02	0.000	0.000	−9.8109E−03
coefficient(B)
8th	0.000	2.6907E−03	0.000	0.000	5.1140E−03
coefficient(C)
10th	0.000	4.1402E−05	0.000	0.000	6.9618E−03
coefficient(D)

In addition, the optical imaging system configured as described above may have aberration characteristics illustrated in FIG. 20.

As set forth above, according to an optical lens system according to one or more embodiments of the present disclosure, a size of the optical imaging system may be reduced, and a high-resolution image may be captured.

While specific examples have been shown and described above, it will be apparent after an understanding of this disclosure that various changes in form and details may be made in 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. Descriptions of features or aspects in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the disclosure is defined not by the detailed description, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.

Claims

1. An optical imaging system, comprising:

a first lens having positive refractive power;

a second lens having refractive power;

a third lens having refractive power;

a fourth lens having refractive power;

a fifth lens having negative refractive power, wherein the first to fifth lenses are sequentially disposed; and

a reflective member having a plurality of reflective surfaces to reflect the light refracted by the fifth lens multiple times,

wherein 3<BFL/TL<7 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TL is a distance on an optical axis from an object-side surface of the first lens to the image-side surface of the fifth lens.

2. The optical imaging system of claim 1, wherein 1<TTL/BFL<2 is satisfied, where TTL is a distance on an optical axis from an object-side surface of the first lens to the imaging plane.

3. The optical imaging system of claim 1, wherein the reflective member comprises an incident surface into which light refracted by the fifth lens is incident, a first reflective surface for reflecting the light, a second reflective surface for reflecting the light reflected from the first reflective surface, and an emission surface from which light reflected from the second reflective surface is emitted,

wherein PL/TTL<0.8 is satisfied, where PL is a distance on an optical axis from the incident surface of the reflective member to the emission surface, and TTL is a distance on an optical axis from the object-side surface of the first lens to the imaging plane.

4. The optical imaging system of claim 1, wherein 1.3<f/f1<2.1 is satisfied, where f is a total focal length of the first to fifth lenses, and f1 is a focal length of the first lens.

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

6. The optical imaging system of claim 1, wherein 0<f1/|f23|<0.3 is satisfied, where f1 is a focal length of the first lens, and f23 is a combined focal length of the second lens and the third lens.

7. The optical imaging system of claim 1, wherein 1<TTL/f<1.5 is satisfied, where TTL is a length on an optical axis from the object-side surface of the first lens to the imaging plane and f is a total focal length of the first to fifth lenses.

8. The optical imaging system of claim 1, wherein 1.63<avg_n23<1.7 is satisfied, where avg_n23 is an average value of a refractive index of the second lens and a refractive index of the third lens.

9. The optical imaging system of claim 1, wherein 2.7<Fno<4.6 is satisfied, where Fno is an F-number of the optical imaging system.

10. The optical imaging system of claim 1, wherein 9<v1−(v2+v3)<37 is satisfied, where v1 is an Abbe number of the first lens, v2 is an Abbe number of the second lens, and v3 is an Abbe number of the third lens.

11. The optical imaging system of claim 1, wherein each of the second lens and the third lens has a refractive index greater than 1.61 and an Abbe number less than 30.

12. The optical imaging system of claim 11, wherein any one of the second lens and the third lens has a refractive index greater than 1.66.

13. The optical imaging system of claim 11, wherein a difference value of Abbe numbers between the first lens and the second lens is greater than 29, and a difference value of Abbe numbers between the second lens and the third lens is less than 7.

14. The optical imaging system of claim 13, wherein the first lens is formed of a glass material having an Abbe number greater than 80, and the second to fifth lenses are formed of a plastic material.

15. The optical imaging system of claim 13, wherein the first lens is formed of a glass material having an Abbe number greater than 80, the second lens is formed of a glass material having an Abbe number less than 30, and the third to fifth lenses are formed of a plastic material.

16. The optical imaging system of claim 1, wherein the first lens has a convex object-side surface and a concave image-side surface, the second lens has a convex object-side surface and a concave image-side surface, the third lens has a concave image-side surface, and the fourth lens has a convex object-side surface.

17. An optical imaging system, comprising:

a first lens having positive refractive power;

a second lens having refractive power;

a third lens having refractive power;

a fourth lens having refractive power;

a fifth lens having negative refractive power, wherein the first to fifth lenses are sequentially disposed; and

a reflective member having a plurality of reflective surfaces to reflect the light refracted by the fifth lens multiple times,

wherein 2.7<Fno<4.6 is satisfied, where Fno is an F-number of the optical imaging system,

wherein 1<TTL/BFL<2 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TTL is a distance on an optical axis from an object-side surface of the first lens to the imaging plane, and

wherein |f1/f2|<0.6 is satisfied, where f1 is the focal length of the first lens, and f2 is the focal length of the second lens.

18. The optical imaging system of claim 17, wherein PL/TTL<0.8 is satisfied, where PL is a distance on an optical axis from the incident surface of the reflective member to the emission surface, and TTL is a distance on an optical axis from the object-side surface of the first lens to the imaging plane.

19. An optical imaging system, comprising:

a first lens having positive refractive power, a convex object-side surface, and a concave image-side surface;

a second lens having refractive power, a convex object-side surface, and a concave image-side surface;

a third lens having refractive power and a concave image-side surface;

a fourth lens having refractive power and a convex object-side surface;

a fifth lens having negative refractive power and a concave image-side surface, wherein the first to fifth lenses are sequentially disposed; and

a reflective member having a plurality of reflective surfaces to reflect the light refracted by the fifth lens multiple times,

wherein 1.3<f/f1<2.1 is satisfied, where f is a total focal length of the first to fifth lenses, and f1 is a focal length of the first lens, and

wherein 1<TTL/BFL<2 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TTL is a distance on an optical axis from an object-side surface of the first lens to the imaging plane.

20. The optical imaging system of claim 19, wherein 3<BFL/TL<7 is satisfied, where BFL is a distance on an optical axis from an image-side surface of the fifth lens to an imaging plane, and TL is a distance on an optical axis from an object-side surface of the first lens to the image-side surface of the fifth lens.