Optical image capturing system

Abstract

The present disclosure relates to an optical imaging system including: a first lens group having at least two reflective surfaces and including a first lens and a second lens; a second lens group including a plurality of lenses; and a reflective member disposed between the first lens group and the second lens group, in which at least two reflective surfaces include a first reflective surface formed on an image-side surface of the second lens and a second reflective surface formed on an object-side surface of the first lens, the object-side surface of the first lens including a first refractive surface, and the object-side surface of the second lens including a second refractive surface. The image-side surface of the second lens includes a second refractive surface, and the reflective member includes a third reflective surface, and a conditional expression f1G / fTlt is satisfied; and 0.9 where f1G is the focal length of the first lens group, and fT is the total focal length of the optical imaging system.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10 - 2023 - 0188813, filed on December 21, 2023, and Korean Patent Application No. 10 - 2024 - 0124995, filed on September 12, 2024, with the Korean Intellectual Property Office. The entire disclosures of the above - mentioned Korean patent applications are incorporated herein by reference for all purposes. Technical Field

[0003] The following description relates to an optical imaging system. Background Art

[0004] Recently, optical imaging systems implemented in portable electronic devices generally have a small form factor and high magnification (telephoto) performance.

[0005] However, since an optical imaging system with high magnification (telephoto) performance must have a long focal length, there is a problem that the size of the optical imaging system inevitably increases.

[0006] Accordingly, an optical imaging system that bends light through a reflective member has been proposed.

[0007] In addition, a structure has recently been proposed in which a part of the lens of an optical imaging system is disposed in front of the reflective member.

[0008] However, even with these conventional optical imaging systems, the optical imaging system still has a relatively large size, which limits the installation of high - resolution optical imaging systems in portable electronic devices.

[0009] The above information is presented as background information only to assist in understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above constitutes prior art with respect to the present disclosure. Summary of the Invention

[0010] The present Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. The present Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to assist in determining the scope of the claimed subject matter.

[0011] In general, an optical imaging system includes: a first lens group including a first lens and a second lens arranged along a first optical axis and having at least two reflective surfaces; a second lens group including a plurality of lenses arranged along a second optical axis and spaced apart from the first lens group; and a reflective member disposed between the first lens group and the second lens group, wherein the at least two reflective surfaces include a first reflective surface disposed on an image side surface of the second lens and a second reflective surface disposed on an object side surface of the first lens, wherein the object side surface of the first lens includes a first refractive surface extending outward from the second reflective surface, wherein the image side surface of the second lens includes a second refractive surface disposed outward from the first reflective surface, wherein the reflective member includes a third reflective surface, and satisfies the conditional expression f1G / fT < 0.9, where f1G is the focal length of the first lens group, and fT is the total focal length of the optical imaging system.

[0012] The first lens group may have a positive refractive power, and the second lens group may have a negative refractive power.

[0013] The conditional expression f1G > 0 and Rp < 0 may be satisfied, where Rp is the radius of curvature of the first reflective surface of the second lens of the first lens group.

[0014] The conditional expression 2 mm < d < 3 mm may be satisfied, where d is the distance along the first optical axis from the object side surface of the first lens of the first lens group to the image side surface of the second lens of the first lens group.

[0015] The conditional expression 0.2 < |(2 × d) / Rp| < 0.6 may be satisfied, where d is the distance along the first optical axis from the object side surface of the first lens of the first lens group to the image side surface of the second lens of the first lens group, and Rp is the radius of curvature of the first reflective surface of the second lens of the first lens group.

[0016] The conditional expression 0.4 < Hs / Hp < 0.6 may be satisfied, where Hp is the effective diameter of the object side surface of the first lens of the first lens group, and Hs is the effective diameter of the second reflective surface of the first lens of the first lens group.

[0017] The reflective member may further include an incident surface and an exit surface, and the third reflective surface is disposed between the incident surface and the exit surface, and the conditional expression 0.4 < d / Ph < 0.8 may be satisfied, where d is the distance along the first optical axis from the object side surface of the first lens of the first lens group to the image side surface of the second lens of the first lens group, and Ph is the sum of the distance along the first optical axis from the incident surface to the third reflective surface and the distance along the second optical axis from the third reflective surface to the exit surface.

[0018] It can satisfy the conditional expression L / fT < 0.8, where L is the sum of the distance along the second optical axis from the third reflection surface to the imaging surface disposed on the second optical axis and the effective radius of the first lens.

[0019] It can satisfy the conditional expression 0.5 < Rs / Rp < 1.3, where Rs is the radius of curvature of the second reflection surface of the first lens of the first lens group, and Rp is the radius of curvature of the first reflection surface of the second lens of the first lens group.

[0020] It can satisfy the conditional expression 1 < f1G / Rp < 2.3, where Rp is the radius of curvature of the first reflection surface of the second lens of the first lens group.

[0021] It can satisfy the conditional expression 0.1 < Lf / fT < 0.7, where Lf is the distance along the first optical axis from the second reflection surface of the first lens of the first lens group to the third reflection surface of the reflecting member.

[0022] It can satisfy the conditional expression 0.2 < Lf / Lr < 0.5, where Lf is the distance along the first optical axis from the second reflection surface of the first lens of the first lens group to the third reflection surface of the reflecting member, and Lr is the distance along the second optical axis from the third reflection surface of the reflecting member to the imaging surface.

[0023] The first lens can have a negative refractive power, and the second lens can have a positive refractive power.

[0024] The plurality of lenses of the second lens group can include a third lens, a fourth lens, and a fifth lens arranged in sequence along the second optical axis, and among them, the fifth lens can have a positive refractive power.

[0025] According to the following detailed description, drawings, and claims, other features and aspects will be apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The configuration diagram of an exemplary optical imaging system according to the first embodiment is shown.

[0027] Figure 2 Shows Figure 1 The aberration characteristics of the exemplary optical imaging system shown in

[0028] Figure 3 The configuration diagram of an exemplary optical imaging system according to the second embodiment is shown.

[0029] Figure 4 Shows Figure 3 The aberration characteristics of the exemplary optical imaging system shown in

[0030] Figure 5Shows a configuration diagram of an exemplary optical imaging system according to a third embodiment.

[0031] Figure 6 Shows Figure 5 the aberration characteristics of the exemplary optical imaging system shown in

[0032] Figure 7 Shows an exemplary optical imaging system according to one or more embodiments.

[0033] Figure 8 Shows a plan view of a first lens of an optical imaging system according to one or more embodiments. Detailed Description

[0034] The following detailed description is provided to assist the reader in obtaining 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 understanding the disclosure of this application. For example, the order of operations described herein and / or the order within an operation are merely examples and are not limited to the order set forth herein, but rather can be changed as will be apparent after understanding the disclosure of this application, except for the order of operations and / or the order within an operation that must occur in a specific order. As another example, the order of operations and / or the order within an operation can be performed in parallel, except for at least a portion of the order of operations and / or at least a portion of the order within an operation that must occur in a certain order (e.g., a specific order). Additionally, descriptions of features known after understanding the disclosure of this application may be omitted for the sake of clarity and conciseness.

[0035] Although terms such as "first," "second," and "third" or A, B, (a), (b), etc. may be used herein to describe various members, components, regions, layers, or parts, these members, components, regions, layers, or parts are not limited by these terms. Each of these terms is not used to define, for example, the nature, order, or sequence of the corresponding member, component, region, layer, or part, but rather is only used to distinguish the corresponding member, component, region, layer, or part from other members, components, regions, layers, or parts. Thus, the first member, first component, first region, first layer, or first part referred to in the examples described herein may also be referred to as the second member, second component, second region, second layer, or second part without departing from the teachings of the examples.

[0036] Throughout the specification, when a component, element, or layer is described as being "on," "connected to," "coupled to," or "joined to" another component, element, or layer, it can be directly "on" the other component, element, or layer (e.g., in contact with the other component, element, or layer), directly "connected to," directly "coupled to," or directly "joined to" the other component, element, or layer, or there can reasonably be one or more other components, elements, or layers therebetween. When a component, element, or layer is described as being "directly" "on," "directly connected to," "directly coupled to," or "directly joined to" another component, element, or layer, there are no other components, elements, or layers therebetween. Similarly, expressions such as "between" and "immediately between" and "adjacent to" and "immediately adjacent to" can be interpreted as described above.

[0037] The terms used herein are for the purpose of describing various examples only and are not intended to limit the disclosure. The phrases "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. As a non-limiting example, the terms "comprising," "including," and "having" specify the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof, nor the presence of alternative existences substituting for the stated features, quantities, operations, components, elements, and / or combinations thereof. Additionally, although one embodiment may state that the terms "comprising," "including," and "having" specify the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, there may be other embodiments in which one or more of the stated features, quantities, operations, components, elements, and / or combinations thereof do not exist.

[0038] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more of the associated listed items. Phrases such as "at least one of A, B, and C" and the like are intended to have a separate meaning, and these phrases "at least one of A, B, and C" and the like also include examples in which one or more of A, B, and C can be present (e.g., any combination of one or more of A, B, and C), unless the corresponding description and embodiment require such a list (e.g., "at least one of A, B, and C") to be interpreted as having a combined meaning.

[0039] The features described herein may be implemented in various forms and are not to be construed as limited to the examples described herein. Instead, the examples described herein are provided only to illustrate some of the many possible ways of implementing the methods, apparatuses, and / or systems described herein that will be apparent after understanding the disclosure of the present application. In this document, the term "may" is used with respect to an example or embodiment (e.g., 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 all examples and embodiments are not limited thereto. The terms "example" or "embodiment" used herein have the same meaning (e.g., the phrase "in one example" has the same meaning as "in one embodiment", and "in one or more examples" has the same meaning as "in one or more embodiments").

[0040] In the following lens configuration diagrams, for illustrative purposes, the thickness, dimensions, and shape of the lenses are slightly exaggerated, and in particular, only the spherical or aspherical shapes presented in the lens configuration diagrams are shown as examples and are not limited to that shape.

[0041] An optical imaging system according to one or more embodiments may be mounted on a portable electronic device. In an example, the optical imaging system may be a component of a camera module mounted on a portable electronic device. The portable electronic device may be a portable electronic device such as, but not limited to, a mobile communication terminal, a smart phone, a tablet personal computer (PC), etc.

[0042] In one or more examples, the numerical values of the lens such as the radius of curvature, thickness, distance, focal length, etc. are in millimeters, and the unit of the field of view is degrees.

[0043] In addition, in the description of the shape of each lens, the meaning of a shape in which one surface bulges means that the paraxial region of that surface bulges, and the meaning of a shape in which one surface is recessed means that the paraxial region of that surface is recessed.

[0044] In an example, the paraxial region refers to a very narrow region near the optical axis.

[0045] The imaging surface may mean a virtual plane on which the optical imaging system forms a focal point. Alternatively, the imaging surface may mean a surface of the image sensor that receives light.

[0046] One or more examples may provide an optical imaging system that achieves high resolution while having a small size.

[0047] One or more examples may provide an optical imaging system that reduces the size of the optical imaging system and captures high-resolution images.

[0048] Refer toFigure 7 , according to one or more embodiments, an optical imaging system includes a plurality of lens groups. For example, the optical imaging system may include a first lens group LG1 and a second lens group LG2.

[0049] The first lens group LG1 may include one or more lenses and a plurality of reflective surfaces, and the second lens group LG2 may include a plurality of lenses.

[0050] In an embodiment, the first lens group LG1 may include a first lens L1 and a second lens L2, the second lens L2 includes a first reflective surface RS1, and the first lens L1 includes a second reflective surface RS2. The second lens group LG2 may include a third lens L3, a fourth lens L4, and a fifth lens L5.

[0051] The first lens L1 and the second lens L2 of the first lens group LG1 may be arranged along a first optical axis, and the third lens L3 to the fifth lens L5 of the second lens group LG2 may be arranged along a second optical axis.

[0052] The first optical axis of the first lens group LG1 and the second optical axis of the second lens group LG2 may intersect each other. For example, a virtual line extending on the first optical axis of the first lens group LG1 and a virtual line extending on the second optical axis of the second lens group LG2 may intersect each other.

[0053] In an embodiment, the first optical axis of the first lens group LG1 and the second optical axis of the second lens group LG2 may be perpendicular to each other.

[0054] In a non-limiting example, the first lens group LG1 may have a positive refractive power as a whole, and the second lens group LG2 may have a negative refractive power as a whole.

[0055] The optical imaging system according to one or more embodiments may further include a reflective member P that changes the propagation direction of light. The reflective member P may have a third reflective surface RS3. In an example, the reflective member P may be a mirror or a prism. In an embodiment, the reflective member P may be disposed between the first lens group LG1 and the second lens group LG2.

[0056] When the reflective member P is a prism, the reflective member P may have any shape obtained by dividing a rectangular parallelepiped or a cube in half in the diagonal direction. The reflective member P may include an incident surface, a third reflective surface RS3, and an exit surface. The reflective member P may have three rectangular faces and two triangular faces. In an example, the incident surface, the third reflective surface RS3, and the exit surface of the reflective member P may each have a rectangular shape, and the two side surfaces of the reflective member P may have a generally triangular shape.

[0057] Light passing through the first lens group LG1 can be incident on the incident surface of the reflection member P, the light incident on this incident surface can be reflected on the third reflection surface RS3, and the light reflected on the third reflection surface RS3 can be emitted to the exit surface.

[0058] An optical imaging system according to one or more embodiments can form a long optical path in a relatively narrow space by bending light via the reflection member P.

[0059] Therefore, the optical imaging system can be miniaturized while allowing the optical imaging system to have a long focal length.

[0060] An optical imaging system according to one or more embodiments can have the characteristics of a telephoto lens having a relatively narrow viewing angle and a long focal length.

[0061] The effective diameter of the object side surface of one or more lenses included in the first lens group LG1 and the effective diameter of the image side surface of one or more lenses included in the first lens group LG1 can each be greater than the minor axis length of the incident surface of the reflection member P.

[0062] In an example, when viewed in the first optical axis direction of the first lens group LG1, one or more lenses included in the first lens group LG1 can be substantially circular.

[0063] The effective diameter of the object side surface of a plurality of lenses included in the second lens group LG2 and the effective diameter of the image side surface of a plurality of lenses included in the second lens group LG2 can each be less than the minor axis length of the incident surface of the reflection member P.

[0064] In an example, when viewed from the second optical axis direction of the second lens group LG2, the lenses included in the second lens group LG2 can be substantially circular.

[0065] The optical imaging system can further include an image sensor S that converts an image of an incident object into an electrical signal.

[0066] In addition, the optical imaging system can further include an infrared blocking filter (hereinafter referred to as a filter) that blocks infrared rays. The filter can be disposed between the last lens (e.g., the fifth lens L5) and the image sensor S.

[0067] The first lens group LG1 can include at least two reflection surfaces. Since the first lens group LG1 includes at least two reflection surfaces, the height of the optical imaging system (e.g., the height in the first optical axis direction) can be reduced while achieving a long total focal length (i.e., a telephoto lens).

[0068] In an embodiment, if the first lens group LG1 includes two lenses (e.g., the first lens L1 and the second lens L2), at least two reflecting surfaces may be provided on the lens (the first lens L1) disposed closest to the object side among the two lenses included in the first lens group LG1 and on the lens (the second lens L2) disposed adjacent to the lens disposed closest to the object side.

[0069] For example, the first lens L1 and the second lens L2 may each have at least one reflecting surface.

[0070] At least one reflecting surface may be formed on the object side surface of the first lens L1, and at least one reflecting surface may be formed on the image side surface of the second lens L2.

[0071] In an embodiment, a part of the object side surface of the first lens L1 may serve as a reflecting surface, and a part of the image side surface of the second lens L2 may serve as a reflecting surface.

[0072] Hereinafter, the reflecting surface formed on the image side surface of the second lens L2 is referred to as the first reflecting surface RS1, and the reflecting surface formed on the object side surface of the first lens L1 is referred to as the second reflecting surface RS2.

[0073] The object side surface of the first lens L1 may include the second reflecting surface RS2 and the first refracting surface TS1. In an example, the second reflecting surface RS2 may be formed at the central portion of the object side surface of the first lens L1, and the first refracting surface TS1 may extend from the second reflecting surface RS2 toward the outside of the second reflecting surface RS2. That is, the second reflecting surface RS2 may be disposed inside the first refracting surface TS1.

[0074] In an example, "outside" may refer to a direction away from the first optical axis, and "inside" may refer to a direction close to the first optical axis.

[0075] Since the second reflecting surface RS2 may be formed at the central portion of the object side surface of the first lens L1, light may be blocked from passing through the central portion of the object side surface of the first lens L1. Light may pass through the first refracting surface TS1 on the object side surface of the first lens L1 and enter the second lens L2.

[0076] The image side surface of the second lens L2 may include the first reflecting surface RS1 and the second refracting surface TS2. In an example, the second refracting surface TS2 may be formed at the central portion of the image side surface of the second lens L2, and the first reflecting surface RS1 may extend from the second refracting surface TS2 toward the outside of the second refracting surface TS2. That is, the first reflecting surface RS1 may be disposed outside (or externally) the second refracting surface TS2.

[0077] The light passing through the first lens L1 can be reflected by the first reflection surface RS1 on the image side of the second lens L2 and can return toward the first lens L1. Additionally, the light reflected toward the first lens L1 by the first reflection surface RS1 can be reflected by the second reflection surface RS2 on the object side of the first lens L1, pass through the second lens L2, and advance toward the reflection member P.

[0078] The light passing through the second lens L2 can be reflected by the third reflection surface RS3 of the reflection member P and can enter the second lens group LG2.

[0079] In an embodiment, one or more lenses included in the first lens group LG1 and the multiple lenses included in the second lens group LG2 can each have an aspherical object side and an aspherical image side.

[0080] The aspherical surface of the lens is represented by Equation 1 below.

[0081] Equation 1:

[0082]

[0083] In Equation 1, c represents the curvature of the lens surface (the reciprocal of the radius of curvature), K represents the conic constant, and Y represents the distance from an arbitrary point on the aspherical surface of the lens to the optical axis. Additionally, the constants A to F represent aspherical coefficients. Further, Z represents the distance along the optical axis from an arbitrary point on the aspherical surface of the lens to the vertex of the corresponding aspherical surface.

[0084] The optical imaging system according to one or more embodiments can satisfy at least one of the following conditional expressions.

[0085] In an embodiment, the optical imaging system can satisfy the conditional expressions f1G > 0 and Rp < 0. In an example, f1G is the total focal length of the first lens group LG1, and Rp is the radius of curvature of the first reflection surface RS1 of the second lens L2 of the first lens group LG1. For example, when viewed from the object side, the first reflection surface RS1 of the first lens group LG1 can have a concave shape. That is, the first reflection surface RS1 of the first lens group LG1 can have a shape that bulges toward the image side.

[0086] Therefore, the image brightness can be increased, and the resolution can be improved.

[0087] In an embodiment, the optical imaging system can satisfy the conditional expression 2 mm < d < 3 mm. In an example, d is the distance along the first optical axis from the object side of the first lens L1 to the image side of the second lens L2. Therefore, the optical imaging system can be miniaturized.

[0088] In an embodiment, the optical imaging system may satisfy the conditional expression |(2×d) / Rp| > 0.4. Alternatively, the optical imaging system may satisfy the conditional expression 0.2 < |(2×d) / Rp| < 0.6.

[0089] Accordingly, the image brightness can be increased, and the resolution can be improved.

[0090] In an embodiment, the optical imaging system may satisfy the conditional expression 0.4 < Hs / Hp < 0.6. In an example, Hp is the effective diameter of the object side surface of the first lens L1, and Hs is the effective diameter of the second reflecting surface RS2 of the first lens L1. Accordingly, the image brightness can be increased, and the resolution can be improved.

[0091] In an embodiment, the optical imaging system may satisfy the conditional expression f1G / fT < 0.9. In an example, fT is the total focal length of the optical imaging system. Accordingly, the optical imaging system can be miniaturized.

[0092] In an embodiment, the optical imaging system may satisfy the conditional expression 0.4 < d / Ph < 0.8. In an example, Ph is the sum of the distance along the first optical axis from the incident surface of the reflecting member P to the third reflecting surface RS3 and the distance along the second optical axis from the third reflecting surface RS3 of the reflecting member P to the exit surface.

[0093] Accordingly, the optical imaging system can be miniaturized.

[0094] In an embodiment, the optical imaging system may satisfy the conditional expression L / fT < 0.8. In an example, L is the total track length along the second optical axis of the optical imaging system. For example, L may represent the distance along the second optical axis from the effective diameter end of the first lens group LG1 in the second optical axis direction to the imaging surface. Alternatively, L may represent the sum of the distance along the second optical axis from the third reflecting surface RS3 of the reflecting member P to the imaging surface and the effective radius of the first lens L1.

[0095] Accordingly, the optical imaging system can be miniaturized.

[0096] In an embodiment, the optical imaging system may satisfy the conditional expression 0.5 < Rs / Rp < 1.3. In an example, Rs is the radius of curvature of the second reflecting surface RS2 of the first lens group LG1. For example, the second reflecting surface RS2 of the first lens group LG1 may have a concave shape. Accordingly, the resolution can be improved.

[0097] In an embodiment, the optical imaging system may satisfy the conditional expression 1 < f1G / Rp < 2.3. Correspondingly, the resolution can be improved.

[0098] In an embodiment, the optical imaging system may satisfy the conditional expression 0.1 < Lf / fT < 0.7. In an example, Lf is the distance along the first optical axis from the second reflection surface RS2 of the first lens group LG1 to the third reflection surface RS3 of the reflection member P. Accordingly, the optical imaging system can be miniaturized.

[0099] In an embodiment, the optical imaging system may satisfy the conditional expression 0.2 < Lf / Lr < 0.5. In an example, Lr is the distance along the second optical axis from the third reflection surface RS3 of the reflection member P to the imaging surface. Accordingly, the optical imaging system can be miniaturized.

[0100] Reference will be made to Figure 1 and Figure 2 describe an exemplary optical imaging system 100 according to the first embodiment.

[0101] An exemplary optical imaging system 100 according to one or more embodiments includes a first lens group LG1 and a second lens group LG2. Additionally, the optical imaging system 100 includes a reflection member P disposed between the first lens group LG1 and the second lens group LG2.

[0102] In order from the object side to the imaging surface, the first lens group LG1 includes a first lens 110 and a second lens 120, and the second lens group LG2 includes a third lens 130, a fourth lens 140, and a fifth lens 150.

[0103] Furthermore, the optical imaging system 100 may further include a filter IF and an image sensor.

[0104] The optical imaging system 100 according to the first embodiment can form a focus on the imaging surface IP. The imaging surface IP may refer to the surface on which the optical imaging system 100 forms a focus. For example, the imaging surface IP may refer to a surface of the image sensor that receives light.

[0105] In the first embodiment, the reflection member P may be a prism. However, this is merely an example, and the reflection member P may also be provided as a mirror.

[0106] The lens characteristics (radius of curvature, thickness of the lens or distance between lenses, refractive index, Abbe number, and effective radius) of each lens are shown in Table 1 below.

[0107] In the following table, the "-" sign for the thickness or distance is due to light reflection.

[0108] Table 1:

[0109]

[0110]

[0111] The value listed as the effective radius of the prism in Table 1 refers to the value of the effective radius of the major axis. In the first embodiment, the effective radius of the minor axis of the incident surface of the prism is 2 mm.

[0112] In the first embodiment, the first lens group LG1 may have a positive refractive power as a whole, and the second lens group LG2 may have a negative refractive power as a whole.

[0113] The first lens 110 may have a negative refractive power, the object side surface of the first lens 110 may have a concave shape, and the image side surface of the first lens 110 may have a convex shape.

[0114] The second lens 120 may have a positive refractive power, the object side surface of the second lens 120 may have a concave shape, and the image side surface of the second lens 120 may have a convex shape.

[0115] The third lens 130 may have a negative refractive power, the object side surface of the third lens 130 may have a concave shape, and the image side surface of the third lens 130 may have a convex shape.

[0116] The fourth lens 140 may have a negative refractive power, and the object side surface and the image side surface of the fourth lens 140 may have a concave shape.

[0117] The fifth lens 150 may have a positive refractive power, and the object side surface and the image side surface of the fifth lens 150 may have a convex shape.

[0118] In the example, each surface of the first lens 110 to the fifth lens 150 may have an aspherical coefficient as shown in Table 2 below. In the example, the object side surface and the image side surface of each of the first lens 110 to the fifth lens 150 are aspherical.

[0119] Table 2:

[0120]

[0121]

[0122] Reference will be made to Figure 3 and Figure 4 to describe an exemplary optical imaging system 200 according to the second embodiment.

[0123] The optical imaging system 200 according to the second embodiment includes a first lens group LG1 and a second lens group LG2. In addition, the optical imaging system 200 includes a reflection member P disposed between the first lens group LG1 and the second lens group LG2.

[0124] In the order from the object side to the imaging surface, the first lens group LG1 includes a first lens 210 and a second lens 220, and the second lens group LG2 includes a third lens 230, a fourth lens 240, and a fifth lens 250.

[0125] In addition, the optical imaging system 200 may further include a filter IF and an image sensor.

[0126] The optical imaging system 200 according to the second embodiment can form a focal point on the imaging surface IP. The imaging surface IP may refer to the surface on which the optical imaging system 200 forms a focal point. As an example, the imaging surface IP may refer to a surface of the image sensor that receives light.

[0127] In the second embodiment, the reflecting member P may be a prism. However, this is only an example, and the reflecting member P may also be provided as a mirror.

[0128] The lens characteristics (curvature radius, thickness of the lens or distance between lenses, refractive index, Abbe number, and effective radius) of each lens are shown in Table 3 below.

[0129] Table 3:

[0130]

[0131]

[0132] The value described as the effective radius of the prism in Table 3 refers to the value of the major-axis effective radius. In the second embodiment, the minor-axis effective radius of the incident surface of the prism is 2 mm.

[0133] In the second embodiment, the first lens group LG1 may have a positive refractive power as a whole, and the second lens group LG2 may have a negative refractive power as a whole.

[0134] The first lens 210 may have a negative refractive power, the object side surface of the first lens 210 may have a concave shape, and the image side surface of the first lens 210 may have a convex shape.

[0135] The second lens 220 may have a positive refractive power, the object side surface of the second lens 220 may have a concave shape, and the image side surface of the second lens 220 may have a convex shape.

[0136] The third lens 230 may have a positive refractive power, the object side surface of the third lens 230 may have a concave shape, and the image side surface of the third lens 230 may have a convex shape.

[0137] The fourth lens 240 may have a negative refractive power, and the object side surface and the image side surface of the fourth lens 240 may have a concave shape.

[0138] The fifth lens 250 may have a positive refractive power, the object side surface of the fifth lens 250 may have a convex shape, and the image side surface of the fifth lens 250 may have a concave shape.

[0139] In the example, each surface of the first lens 210 to the fifth lens 250 may have an aspherical coefficient as shown in Table 4 below. In the example, the object side surface and the image side surface of each of the first lens 210 to the fifth lens 250 may be aspherical.

[0140] Table 4:

[0141]

[0142]

[0143] Reference will be made to Figure 5 and Figure 6 to describe an exemplary optical imaging system 300 according to the third embodiment.

[0144] An exemplary optical imaging system 300 according to the third embodiment includes a first lens group LG1 and a second lens group LG2. Additionally, the optical imaging system 300 includes a reflection member P disposed between the first lens group LG1 and the second lens group LG2.

[0145] In the order from the object side to the imaging surface, the first lens group LG1 may include a first lens 310 and a second lens 320, and the second lens group LG2 may include a third lens 330, a fourth lens 340, and a fifth lens 350.

[0146] Additionally, the optical imaging system 300 may further include a filter IF and an image sensor.

[0147] The optical imaging system 300 according to the third embodiment may form a focus on the imaging surface IP. The imaging surface IP may refer to the surface on which the optical imaging system 300 forms a focus. As an example, the imaging surface IP may refer to one surface of the image sensor that receives light.

[0148] In the third embodiment, the reflection member P may be a prism. However, this is only an example, and the reflection member P may also be provided as a mirror.

[0149] The lens characteristics (radius of curvature, thickness of the lens or distance between lenses, refractive index, Abbe number, and effective radius) of each lens are shown in Table 5 below.

[0150] Table 5

[0151]

[0152]

[0153] The value of the effective radius of the prism described in Table 5 refers to the value of the effective radius of the major axis. In the third embodiment, the effective radius of the minor axis of the incident surface of the prism is 2 mm.

[0154] In the third embodiment, the first lens group LG1 may have a positive refractive power as a whole, and the second lens group LG2 may have a negative refractive power as a whole.

[0155] The first lens 310 may have a negative refractive power. The object side surface of the first lens 310 may have a concave shape, and the image side surface of the first lens 310 may have a convex shape.

[0156] The second lens 320 may have a positive refractive power. The object side surface of the second lens 320 may have a concave shape, and the image side surface of the second lens 320 may be a convex shape.

[0157] The third lens 330 may have a negative refractive power. The object side surface of the third lens 330 may have a convex shape, and the image side surface of the third lens 330 may have a concave shape.

[0158] The fourth lens 340 may have a negative refractive power. The object side surface of the fourth lens 340 may have a convex shape, and the image side surface of the fourth lens 340 may have a concave shape.

[0159] The fifth lens 350 may have a positive refractive power. The object side surface of the fifth lens 350 may have a convex shape, and the image side surface of the fifth lens 350 may have a concave shape.

[0160] In the example, each surface of the first lens 310 to the fifth lens 350 may have an aspherical coefficient as shown in Table 6 below. In the example, the object side surface and the image side surface of each of the first lens 310 to the fifth lens 350 may be aspherical.

[0161] Table 6:

[0162]

[0163]

[0164] Table 7:

[0165]

[0166]

[0167] In Table 7, fT 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 light reflected from the first reflecting surface of the second lens, f3 is the focal length of the light reflected from the second reflecting surface of the first lens, f4 is the focal length of the second lens, f5 is the focal length of the third lens, f6 is the focal length of the fourth lens, and f7 is the focal length of the fifth lens.

[0168] f1G is the total focal length of the first lens group, and f2G is the total focal length of the second lens group.

[0169] IMG HT is half of the diagonal length of the imaging surface, Rs is the radius of curvature of the second reflecting surface of the first lens group, Rp is the radius of curvature of the first reflecting surface of the first lens group, Hp is the effective diameter of the object side surface of the first lens, and Hs is the effective diameter of the second reflecting surface of the first lens.

[0170] L is the sum of the distance along the second optical axis from the third reflecting surface of the reflecting member to the imaging surface and the effective radius of the first lens, Lf is the distance along the first optical axis from the second reflecting surface of the first lens group to the third reflecting surface of the reflecting member, and Lr is the distance along the second optical axis from the third reflecting surface of the reflecting member to the imaging surface.

[0171] d is the distance along the first optical axis from the object side surface of the first lens to the image side surface of the second lens, and Ph is the sum of the distance along the first optical axis from the incident surface of the reflecting member to the third reflecting surface and the distance along the second optical axis from the third reflecting surface of the reflecting member to the exit surface.

[0172] TTL is the sum of Lf and Lr, and BFL is the distance along the second optical axis from the image side surface of the last lens of the second lens group to the imaging surface.

[0173] Figure 8 The plan view of the first lens of an exemplary optical imaging system is shown. H S Denotes the auxiliary mirror or diameter of the lens, and H P Denotes the main mirror or diameter of the lens.

[0174] Although the present disclosure includes specific embodiments, it will be apparent after understanding the disclosure of the present application that various changes in form and detail can be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are considered to be merely descriptive and not for the purpose of limitation. The description of the features or aspects in each example is considered applicable to the similar features or aspects in other examples. Appropriate results can also be obtained if the described techniques are performed in a different order, and / or if the components in the described systems, architectures, devices, or circuits are combined in a different manner and / or replaced or supplemented by other components or their equivalents.

[0175] Accordingly, in addition to the foregoing and the disclosures of all the accompanying drawings, the scope of the present disclosure also includes the claims and their equivalents, that is, all variations within the scope of the claims and their equivalents will be construed as being included in the present disclosure.

Claims

1. An optical imaging system, comprising: A first lens group, including a first lens and a second lens arranged along a first optical axis, and having at least two reflective surfaces; A second lens group, including a plurality of lenses arranged along a second optical axis, and spaced apart from the first lens group; And A reflective member, disposed between the first lens group and the second lens group, Wherein, the at least two reflective surfaces include a first reflective surface disposed on the image side of the second lens and a second reflective surface disposed on the object side of the first lens, Wherein, the object side of the first lens includes a first refractive surface, and the first refractive surface extends outward from the second reflective surface, Wherein, the image side of the second lens includes a second refractive surface, and the second refractive surface is disposed inward from the first reflective surface, Wherein, the reflective member includes a third reflective surface, Wherein, the optical imaging system has a total of five lenses, and Wherein, the condition expression f1G / fT < 0.9 is satisfied, where f1G is the focal length of the first lens group, and fT is the total focal length of the optical imaging system.

2. The optical imaging system according to claim 1, wherein: The first lens group has a positive refractive power, and the second lens group has a negative refractive power.

3. The optical imaging system according to claim 1, wherein: The condition expression f1G > 0 and Rp < 0 are satisfied, where Rp is the radius of curvature of the first reflective surface of the second lens of the first lens group.

4. The optical imaging system according to claim 1, wherein: The condition expression 2mm < d < 3mm is satisfied, where d is the distance along the first optical axis from the object side of the first lens of the first lens group to the image side of the second lens of the first lens group.

5. The optical imaging system according to claim 1, wherein: The condition expression 0.2 < |(2×d) / Rp| < 0.6 is satisfied, where d is the distance along the first optical axis from the object side of the first lens of the first lens group to the image side of the second lens of the first lens group, and Rp is the radius of curvature of the first reflective surface of the second lens of the first lens group.

6. The optical imaging system according to claim 1, wherein: The condition expression 0.4 < Hs / Hp < 0.6 is satisfied, where Hp is the effective diameter of the object side of the first lens of the first lens group, and Hs is the effective diameter of the second reflective surface of the first lens of the first lens group.

7. The optical imaging system according to claim 1, wherein: The reflective member further includes an incident surface and an exit surface, and the third reflective surface is disposed between the incident surface and the exit surface, and Wherein, the condition expression 0.4 < d / Ph < 0.8 is satisfied, where d is the distance along the first optical axis from the object side of the first lens of the first lens group to the image side of the second lens of the first lens group, and Ph is the sum of the distance along the first optical axis from the incident surface to the third reflective surface and the distance along the second optical axis from the third reflective surface to the exit surface.

8. The optical imaging system according to claim 1, wherein: The condition expression L / fT < 0.8 is satisfied, where L is the sum of the distance along the second optical axis from the third reflective surface to the imaging surface disposed on the second optical axis and the effective radius of the first lens.

9. The optical imaging system according to claim 1, wherein: The condition expression 0.5 < Rs / Rp < 1.3 is satisfied, where Rs is the radius of curvature of the second reflecting surface of the first lens of the first lens group, and Rp is the radius of curvature of the first reflecting surface of the second lens of the first lens group.

10. The optical imaging system according to claim 1, wherein: The condition expression 1 < f1G / Rp < 2.3 is satisfied, where Rp is the radius of curvature of the first reflecting surface of the second lens of the first lens group.

11. The optical imaging system according to claim 1, wherein: The condition expression 0.1 < Lf / fT < 0.7 is satisfied, where Lf is the distance along the first optical axis from the second reflecting surface of the first lens of the first lens group to the third reflecting surface of the reflecting member.

12. The optical imaging system according to claim 1, wherein: The condition expression 0.2 < Lf / Lr < 0.5 is satisfied, where Lf is the distance along the first optical axis from the second reflecting surface of the first lens of the first lens group to the third reflecting surface of the reflecting member, and Lr is the distance along the second optical axis from the third reflecting surface of the reflecting member to the imaging surface.

13. The optical imaging system according to claim 1, wherein: The first lens has a negative refractive power, and the second lens has a positive refractive power.

14. The optical imaging system according to claim 1, wherein: The plurality of lenses of the second lens group includes a third lens, a fourth lens, and a fifth lens arranged in sequence along the second optical axis, and wherein the fifth lens has a positive refractive power.

Images