Imaging lens system, camera module, and electronic device

Abstract

The present disclosure relates to an imaging lens system, including: a light path folding member including a first reflection surface, a last reflection surface, and a rear reflection surface, wherein the first reflection surface is disposed closest to an object side, the last reflection surface is disposed closest to an imaging surface, and the rear reflection surface is disposed to form an acute angle with the last reflection surface and is configured to reflect light reflected by the last reflection surface to the imaging surface; and a first lens group disposed on an object side of the first reflection surface or on an image side of the first reflection surface, wherein an angle between a first virtual plane including the first reflection surface and a second virtual plane including the last reflection surface is 15 degrees to 27 degrees. The present disclosure also relates to a camera module including the imaging lens system and an electronic device including the camera module.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2021-0133480, filed on October 7, 2021, with the Korean Intellectual Property Office, and Korean Patent Application No. 10-2022-0043821, filed on April 8, 2022, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] This disclosure relates to a telephoto imaging lens system that can be mounted on a portable electronic device. Background Technology

[0004] Achieving an imaging lens system with a long focal length and reduced thickness and size (hereinafter referred to as a telephoto imaging lens system) can be challenging, and therefore such a system may be difficult to install in small terminals. However, the growing demand for functional and performance improvements in small terminals (e.g., smartphones) may lead to an increasing need for installing telephoto imaging lens systems in such small terminals.

[0005] The above information is presented as background information only to aid in understanding this disclosure. No determination or assertion is made as to whether any of the above content can be used as prior art with respect to this disclosure. Summary of the Invention

[0006] The summary portion of this invention is intended to provide a brief overview of the chosen inventive concepts, which will be further described in the detailed description portion below. This summary portion is not intended to identify key or essential features of the claimed subject matter, nor to help determine the scope of the claimed subject matter.

[0007] In one general aspect, the imaging lens system includes: an optical path folding member including a foremost reflecting surface, a last reflecting surface, and a rear reflecting surface, wherein the foremost reflecting surface is disposed closest to the object side, the last reflecting surface is disposed closest to the imaging surface, and the rear reflecting surface is disposed at an acute angle with the last reflecting surface and configured to reflect light reflected by the last reflecting surface to the imaging surface; and a first lens group disposed on the object side of the foremost reflecting surface or on the image side of the foremost reflecting surface, including an angle of 15 degrees to 27 degrees between a first virtual plane of the foremost reflecting surface and a second virtual plane including the last reflecting surface.

[0008] The first lens group may include a first lens and a second lens arranged sequentially from the object side.

[0009] The first lens can have a positive refractive power, and the second lens can have a negative refractive power.

[0010] V1-V2 can be greater than 30, where V1 is an Abbe number of the first lens, and V2 is an Abbe number of the second lens.

[0011] An angle between the last reflection surface and the back reflection surface can be 18 degrees to 30 degrees.

[0012] The optical path folding member can further include a first optical path folding member having the frontmost reflection surface, and a second optical path folding member having the back reflection surface and the last reflection surface.

[0013] The imaging lens system can further include a second lens group disposed on an object side or an image side of the frontmost reflection surface on which the first lens group is not disposed.

[0014] The second lens group can include one or more lenses.

[0015] BFL / TTL can be less than 0.9, where BFL is a distance from an image side surface of a last lens of the first lens group to an imaging surface, and TTL is a distance from an object side surface of a frontmost lens of the first lens group to the imaging surface.

[0016] The camera module can include the imaging lens system and an image sensor, wherein the imaging surface can be disposed on the image sensor.

[0017] The electronic device can include the camera module, wherein the image sensor is diagonally disposed with respect to a thickness direction of the electronic device.

[0018] In another general aspect, an imaging lens system includes a first optical path folding member having one reflection surface and having a cross-sectional shape of a right triangle; a second optical path folding member having two or more reflection surfaces and having a cross-sectional shape of a right triangle; a lens unit disposed to face an incidence surface or an exit surface of the first optical path folding member; and an imaging surface disposed to face a total reflection surface of the second optical path folding member, wherein the first optical path folding member, the second optical path folding member, and the imaging surface are sequentially arranged along an optical axis of the lens unit.

[0019] The second optical path folding member can include a first reflection surface that reflects light emitted from the first optical path folding member, and a second reflection surface that reflects light reflected from the first reflection surface to the first reflection surface.

[0020] An angle between the first reflection surface and the second reflection surface can be 16 degrees to 32 degrees.

[0021] A maximum length of the entrance surface of the first optical path folding member can be less than a maximum length of the exit surface of the second optical path folding member.

[0022] A distance from the exit surface of the first optical path folding member to the entrance surface of the second optical path folding member can be greater than a distance from the exit surface of the second optical path folding member to the imaging surface.

[0023] The lens unit can include a first lens group disposed on an object side of the first optical path folding member.

[0024] The lens unit can include a first lens group disposed between the first optical path folding member and the second optical path folding member.

[0025] The lens unit can include a first lens group disposed on an object side of the first optical path folding member, and a second lens group disposed between the first optical path folding member and the second optical path folding member.

[0026] The camera module can include an imaging lens system.

[0027] The electronic device can include a camera module, wherein the imaging surface can be disposed on an image sensor, and the image sensor can be disposed diagonally with respect to a thickness direction of the electronic device.

[0028] In another general aspect, an imaging lens system includes: an optical path folding member including a first reflection surface, a second reflection surface, and a third reflection surface configured to sequentially reflect light incident from an object side; and a first lens group disposed on an object side or an image side of the first reflection surface, wherein a first incident angle of the first reflection surface is less than a second incident angle of the second reflection surface, and a third incident angle of the third reflection surface is less than the first incident angle of the first reflection surface.

[0029] The first incident angle and the second incident angle can be greater than a critical angle of the first reflection surface and a critical angle of the second reflection surface, respectively, and the third incident angle can be less than a critical angle of the third reflection surface.

[0030] The first incident angle and the second incident angle can be greater than 36 degrees and less than 90 degrees, respectively.

[0031] The third incident angle can be greater than 28 degrees and less than 56 degrees.

[0032] The imaging surface can be disposed to face the second reflection surface.

[0033] The electronic device can include: a camera module including an imaging lens system; and an image sensor including an imaging surface disposed to face the second reflection surface, wherein the image sensor can be disposed diagonally with respect to a thickness direction of the electronic device.

[0034] In another general aspect, an imaging lens system includes: a first lens having a positive refractive power; a second lens having a negative refractive power, a convex object side surface, and a concave image side surface; a third lens having a refractive power and a concave image side surface; and a first reflective surface, a second reflective surface, and a third reflective surface sequentially disposed from an object side along an optical axis, wherein the first lens, the second lens, the third lens, the second reflective surface, and the third reflective surface are sequentially disposed from the object side along the optical axis.

[0035] An angle between a first virtual plane including the first reflective surface and a second virtual plane including the second reflective surface can be 15 degrees to 27 degrees.

[0036] The imaging lens system can further include an imaging surface disposed along the optical axis and parallel to the virtual plane including the second reflective surface.

[0037] A first incident angle of the first reflective surface can be less than a second incident angle of the second reflective surface, and a third incident angle of the third reflective surface can be less than the first incident angle of the first reflective surface.

[0038] The imaging lens system can further include a fourth lens having a refractive power and disposed along the optical axis between the first reflective surface and the second reflective surface.

[0039] The imaging lens system can further include a fourth reflective surface and a fifth reflective surface disposed along the optical axis between the first reflective surface and the second reflective surface.

[0040] The optical axis can extend between the second reflective surface and the third reflective surface a plurality of times.

[0041] The third lens can be disposed along the optical axis between the first reflective surface and the second reflective surface.

[0042] An electronic device can include: a camera module including the imaging lens system; and an image sensor including an imaging surface disposed to face the second reflective surface, wherein the image sensor can be diagonally disposed with respect to a thickness direction of the electronic device.

[0043] Other features and aspects will become apparent from the accompanying claims, drawings, and specific embodiments described below. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is an imaging lens system according to a first exemplary embodiment.

[0045] Figure 2 is an aberration curve of the imaging lens system shown in Figure 1

[0046] Figure 3 is an aberration curve of the imaging lens system shown in Figure 1 ​Configuration diagram of a modification example of the imaging lens system shown.

[0047] Figure 4 is Figure 1 Configuration diagram of another modification example of the imaging lens system shown.

[0048] Figure 5 is a diagram of an imaging lens system according to a second exemplary embodiment.

[0049] Figure 6 is Figure 5 Aberration curves of the imaging lens system shown.

[0050] Figure 7 is a diagram of an imaging lens system according to a third exemplary embodiment.

[0051] Figure 8 is Figure 7 Aberration curves of the imaging lens system shown.

[0052] Figure 9 is Figure 7 Configuration diagram of a modification example of the imaging lens system shown.

[0053] Figure 10 is Figure 7 Configuration diagram of another modification example of the imaging lens system shown.

[0054] Figure 11 is a diagram of an imaging lens system according to a fourth exemplary embodiment.

[0055] Figure 12 is Figure 11 Aberration curves of the imaging lens system shown.

[0056] Figure 13 is a diagram of an imaging lens system according to a fifth exemplary embodiment.

[0057] Figure 14 is Figure 13 Aberration curves of the imaging lens system shown.

[0058] Figure 15 is a diagram of an imaging lens system according to a sixth exemplary embodiment.

[0059] Figure 16 is Figure 15 Aberration curves of the imaging lens system shown.

[0060] Figure 17 is a diagram of an imaging lens system according to a seventh exemplary embodiment.

[0061] Figure 18 is Figure 17Aberration curves of the illustrated imaging lens system.

[0062] Figure 19 is a diagram of an imaging lens system according to an eighth exemplary embodiment.

[0063] Figure 20 is Figure 19 Aberration curves of the illustrated imaging lens system.

[0064] Figure 21 is a perspective view of an electronic device according to an exemplary embodiment.

[0065] Figure 22 is a partial cross-sectional view of the electronic device taken along Figure 21 line I-I.

[0066] Throughout the drawings and specific embodiments, identical reference numerals designate identical elements. The drawings can not be to scale and the relative dimensions, proportions and depiction of elements in the drawings can be exaggerated for purpose of clarity, illustration and convenience. DETAILED DESCRIPTION

[0067] Hereinafter, although exemplary embodiments of the disclosure will be described, for example, with reference to the accompanying drawings, it should be noted that the exemplary embodiments are not limited thereto. Terms denoting components of the disclosure can be named in consideration of functions of each component. Accordingly, these terms should not be construed as limiting technical components of the disclosure.

[0068] The following detailed description is provided to help the reader obtain a thorough understanding of the methods, apparatuses, and / or systems described herein. However, various changes, modifications, and equivalents in the methods, apparatuses, and / or systems described herein will be apparent after an understanding of the present disclosure. For example, the order of the operations described herein is merely an example, and is not limited to the order set forth herein, except for operations that must occur in a specific order, and can be changed, which will be apparent after an understanding of the present disclosure. In addition, descriptions of features well known in the art can be omitted for more clarity and conciseness.

[0069] The features described herein can be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, these examples are provided so that the many possible implementations of the methods, apparatuses, and / or systems described herein, which will be apparent after an understanding of the present disclosure, are fully conveyed.

[0070] Throughout this disclosure, when an element such as a layer, region, or substrate is referred to as being "on", "connected to", or "coupled to" another element, it can be directly on, directly connected to, or directly coupled to the other element, or one or more other elements can be interposed between them. Conversely, when an element is referred to as being "directly on", "directly connected to", or "directly coupled to" another element, then there are no other elements interposed between them.

[0071] As used herein, the term "and / or" includes any one of the associated listed items, as well as any combination of any two or more of the associated listed items; likewise, "at least one of' includes any one of the associated listed items, as well as any combination of any two or more of the associated listed items.

[0072] Although the terms such as "first", "second", and "third" can be used herein to describe various components, parts, regions, layers, or sections, these components, parts, regions, layers, or sections are not limited by the terms. Rather, the terms are only used to distinguish one component, part, region, layer, or section from another component, part, region, layer, or section. Thus, the first component, first part, first region, first layer, or first section mentioned in the examples described herein can also be called the second component, second part, second region, second layer, or second section without departing from the teachings of the examples described herein.

[0073] Spatially relative terms such as "on", "upper", "lower", "below", "above", and the like can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms can be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "upper" relative to other elements or features would then be oriented "below" or "lower" relative to the other elements or features. Accordingly, the expression "above" encompasses both "above" and "below" orientations with respect to the spatial orientation of the device. The device can be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0074] The terminology used herein is for the purpose of describing various examples only and is not intended to be limiting of the present disclosure. As used herein, the articles "a," "an" and "the" are intended to include one or more items, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "includes," "including" and "has" are intended to be inclusive and allow for

[0075] Variations in the shapes illustrated in the drawings can occur due to manufacturing techniques and / or tolerances. Thus, the examples described herein are not intended to be limited to the precise shapes illustrated in the drawings, but include variations in shapes that occur in the manufacturing process.

[0076] It should be noted that the word "comprise", "comprising", "comprises" used in the context of describing the examples herein, e.g. the examples can comprise or include, means there is no more than the inclusion of that feature or aspect, and the use of "may" in the context of examples, means that there is a possibility of that feature or aspect being included in some examples, but not in others.

[0077] Features of the examples described herein can be combined in a variety of ways as will be apparent after the disclosure is understood. Also, although examples described herein have a variety of configurations, other configurations are possible in light of the disclosure.

[0078] One aspect of the disclosure can provide a tele-imaging lens system having a long focal length, which can be installed in a small terminal.

[0079] In the disclosure, the first lens can indicate a lens closest to an object (or a subject). Also, the number of lenses can indicate the order in which the lenses are disposed in the direction of the optical axis from the object side. For example, the second lens can indicate a lens disposed at the second position from the object side, and the third lens can indicate a lens disposed at the third position from the object side. In the disclosure, the radius of curvature and the thickness of the lens, the TTL (i.e., the distance from the object side surface of the first lens to the image plane), the 2IMG HT (i.e., the diagonal length of the image plane), the IMG HT (i.e., the height of the image plane or 1 / 2 of the 2IMG HT), and the focal length can be expressed in millimeters (mm).

[0080] The thickness of the lens, the distance between the lenses, the TTL, and the angle of incidence can be dimensions calculated on the optical axis of the imaging lens system, respectively. Also, in the description of the lens shape, one convex surface of the lens can indicate that the paraxial region of the corresponding surface is convex, and one concave surface of the lens can indicate that the paraxial region of the corresponding surface is concave. Thus, even in the case of describing one surface of the lens as convex, the edge portion of the lens can be concave. Likewise, even in the case of describing one surface of the lens as concave, the edge portion of the lens can be convex.

[0081] The imaging lens system described herein can be mounted in a portable electronic device. For example, the imaging lens system can be mounted in a smartphone, a laptop computer, an augmented reality device, a virtual reality device, a portable game console, etc. However, the scope and use examples of the imaging lens system described herein can not be limited to the above-described electronic devices. For example, the imaging lens system can be applied to electronic devices that can require high-resolution imaging while providing a narrow installation space.

[0082] The imaging lens system described herein can reduce the external size of the imaging lens system while ensuring a long back focal length (BFL, i.e., the distance from the image side surface of the last lens to the imaging surface). For example, the imaging lens system in the present disclosure can reduce the external size of the imaging lens system while ensuring the BFL required to implement a telephoto imaging lens system by using a reflection member. In another example, the imaging lens system in the present disclosure can provide an imaging surface having a considerable size for implementing high resolution. In another example, the imaging lens system in the present disclosure can have an integrated form mounted in a portable terminal while ensuring a long focal length and a long BFL.

[0083] In the present disclosure, the optical path folding member can indicate any member that can allow light to be reflected. For example, the optical path folding member can collectively indicate all of the reflector, the prism, etc. Accordingly, in the present disclosure, the reflector, the prism, and the optical path folding member can all refer to the same component or interchangeable components.

[0084] The imaging lens system according to the first exemplary embodiment of the present disclosure can include an optical path folding member and a first lens group. In the imaging lens system according to the first exemplary embodiment, the optical path folding member can include a plurality of reflection surfaces. For example, the optical path folding member can include a frontmost reflection surface, a last reflection surface, and a rear reflection surface. The frontmost reflection surface can be disposed closest to the object side, and the last reflection surface can be disposed closest to the imaging surface. The rear reflection surface can be disposed to form an acute angle with the last reflection surface and reflect light reflected by the last reflection surface to the imaging surface.

[0085] In the imaging lens system according to the present exemplary embodiment, the first lens group can be disposed on the object side of the frontmost reflection surface or on the image side of the frontmost reflection surface. However, the first lens group can not be limited to the above-described disposition. The first lens group can include a plurality of lenses. For example, the first lens group can include a first lens and a second lens disposed in order from the object side. In the above-described disposition, the first lens can have a positive refractive power, and the second lens can have a negative refractive power.

[0086] In the imaging lens system according to the present exemplary embodiment, a unique geometric relationship can be present between the reflective surfaces of the optical path folding member. For example, the angle between the foremost reflective surface and the rearmost reflective surface can be 15 to 27 degrees. In another example, the angle between a first virtual plane including the foremost reflective surface and a second virtual plane including the rearmost reflective surface can be 15 to 27 degrees. In another example, the angle between the rearmost reflective surface and the rear reflective surface can be 18 to 30 degrees.

[0087] The optical path folding member can include a plurality of members. For example, the optical path folding member can include a first optical path folding member having the foremost reflective surface and a second optical path folding member having the rear reflective surface and the rearmost reflective surface. The first optical path folding member and the second optical path folding member can each have the shape of a prism. However, the first optical path folding member and the second optical path folding member can not be limited to the shape of a prism. For example, the first optical path folding member and the second optical path folding member can each have the shape of a reflector.

[0088] The imaging lens system according to the present exemplary embodiment can include a plurality of lens groups. For example, the imaging lens system can further include a second lens group disposed on the object side or the image side of the foremost reflective surface on which the first lens group is not disposed. As a specific example, the imaging lens system can include a first lens group disposed on the object side of the foremost reflective surface and a second lens group disposed on the image side of the foremost reflective surface. The first lens group and the second lens group can each include one or more lenses. For example, the first lens group can include two lenses, and the second lens group can include one lens. In another example, the first lens group can include three lenses, and the second lens group can include two lenses. In another example, the first lens group can include two lenses, and the second lens group can include three lenses. However, the lenses included in the first lens group or the second lens group can not be limited to the above-described number.

[0089] An imaging lens system according to a second exemplary embodiment of the disclosure can include a first light path folding member, a second light path folding member, and an imaging surface sequentially disposed from an object side. In the imaging lens system according to the second exemplary embodiment, the first light path folding member and the second light path folding member can each have a cross-sectional shape of a right triangle. For example, the first light path folding member and the second light path folding member can each be a prism having a cross-sectional shape of a right triangle. The imaging lens system according to the second exemplary embodiment can further include a component that converges (or images) incident light to the imaging surface. For example, the imaging lens system according to the second exemplary embodiment can further include a lens unit disposed to face an incident surface or an exit surface of the first light path folding member. In the imaging lens system according to the second exemplary embodiment, the imaging surface can be disposed on one side of the second light path folding member. For example, the imaging surface can be disposed to face a hypotenuse (or a total reflection surface) of the second light path folding member.

[0090] The first light path folding member and the second light path folding member can each include one or more reflection surfaces. For example, the first light path folding member can have one reflection surface, and the second light path folding member can have two or more reflection surfaces. As a specific example, the first light path folding member can include one total reflection surface, and the second light path folding member can include one total reflection surface and one mirror reflection surface (or mirror surface reflection surface). The total reflection surface of the second light path folding member can reflect light emitted from the first light path folding member, and the mirror surface reflection surface can reflect light emitted from the total reflection surface to the total reflection surface (or the imaging surface).

[0091] In the imaging lens system according to the present exemplary embodiment, the second light path folding member can have a unique shape. For example, an angle between the total reflection surface and the mirror surface reflection surface of the second light path folding member can be 16 degrees to 32 degrees. As a specific example, the angle between the total reflection surface and the mirror surface reflection surface of the second light path folding member can be 30 degrees or 18 degrees.

[0092] In the imaging lens system according to the present exemplary embodiment, the second light path folding member can implement multiple internal reflections. In more detail, the second light path folding member can allow an even number of internal reflections. For example, the second light path folding member can allow two or four internal reflections.

[0093] In the imaging lens system according to the present exemplary embodiment, an angle (θP2) between the first reflection surface and the second reflection surface of the second light path folding member can be expressed by the following conditional expression.

[0094] θP2 = 90 / (2n + 1), 2n = N

[0095] In the above conditional expression, "n" can denote a positive integer, and "N" can denote the number of internal reflections of the second optical path folding member. For example, when the number of internal reflections of the second optical path folding member is two, the angle (θP2) can be 30 degrees. In another example, when the number of internal reflections of the second optical path folding member is four, the angle (θP2) can be 18 degrees.

[0096] The number of internal reflections of the second optical path folding member according to the present exemplary embodiment can be six or more. However, the number of internal reflections of the second optical path folding member can not exceed four. In more detail, when the number of internal reflections of the second optical path folding member increases to six or more, the angle (θP2) can decrease to 12.9 degrees or less. In this case, the amount of light incident to the second optical path folding member can also decrease, and the imaging lens system can thus have a significantly reduced resolution. Accordingly, the number of internal reflections of the second optical path folding member can be two or four.

[0097] In the imaging lens system according to the present exemplary embodiment, a unique dimensional relationship can exist between the first optical path folding member and the second optical path folding member. For example, the maximum length of the entrance surface of the first optical path folding member can be less than the maximum length of the exit surface of the second optical path folding member. In another example, the total reflection surface of the first optical path folding member can be less than the total reflection surface of the second optical path folding member.

[0098] In the imaging lens system according to the present exemplary embodiment, the second optical path folding member can be disposed adjacent to the imaging plane. For example, the distance from the exit surface of the second optical path folding member to the imaging plane can be less than the distance from the exit surface of the first optical path folding member to the entrance surface of the second optical path folding member.

[0099] In the imaging lens system according to the present exemplary embodiment, the lens unit can include a plurality of lens groups. For example, the lens unit can include a first lens group disposed on the object side of the first optical path folding member and a second lens group disposed between the first optical path folding member and the second optical path folding member.

[0100] The imaging lens system according to the third exemplary embodiment of the present disclosure can include an optical path folding member and a first lens group. In the imaging lens system according to the present exemplary embodiment, the optical path folding member can include a unique configuration. For example, the optical path folding member can include a first reflection surface, a second reflection surface, and a third reflection surface that sequentially reflect light incident from the object side. Based on the angle of incidence, a predetermined dimensional relationship can exist between the first reflection surface, the second reflection surface, and the third reflection surface. For example, a first angle of incidence of the first reflection surface can be less than a second angle of incidence of the second reflection surface, and a third angle of incidence of the third reflection surface can be less than the first angle of incidence of the first reflection surface.

[0101] The first, second, and third angles of incidence can each have a predetermined size. For example, the first and second angles of incidence can each be greater than 36 degrees and less than 90 degrees. In another example, the third angle of incidence can be greater than 28 degrees and less than 56 degrees.

[0102] The imaging lens system according to the present example embodiment can have an imaging surface formed at a specific position. For example, in the imaging lens system according to the present example embodiment, the imaging surface can be disposed to face the second reflection surface of the optical path folding member.

[0103] The imaging lens system according to the fourth example embodiment of the present disclosure can satisfy one or more of the following conditional expressions. However, the imaging lens system according to the fourth example embodiment alone can not satisfy the following conditional expressions. For example, the imaging lens system according to the first through third example embodiments described above can satisfy one or more of the following conditional expressions.

[0104] BFL / TTL < 0.9

[0105] 30 < V1-V2

[0106] 10 mm < f

[0107] 15 mm < TTL

[0108] In the above conditional expressions, BFL can denote a distance from an image side surface of a lens disposed closest to an imaging surface (hereinafter referred to as a last lens) to the imaging surface, TTL can denote a distance from an object side surface of a lens disposed closest to an object (or subject) (hereinafter referred to as a first lens or a frontmost lens) to the imaging surface, V1 can denote an Abbe number of the first lens (or the frontmost lens), V2 can denote an Abbe number of a second lens (or a lens disposed closest to the image side surface of the first lens), and f is a focal length of the imaging lens system.

[0109] The imaging lens system according to the present disclosure can satisfy the above conditional expressions in a more limited form as follows.

[0110] 0.4 < BFL / TTL < 0.9

[0111] 30 < V1-V2 < 36

[0112] 12 mm < f < 24 mm

[0113] 15 mm < TTL < 26 mm

[0114] The imaging lens system according to the fifth example embodiment of the present disclosure can satisfy one or more of the following conditional expressions independently of the above conditional expressions.

[0115] 0.8 < TTL / f < 1.5

[0116] 1.8 < TTL / f1 < 2.6

[0117] -3.4 < TTL / f2 < -0.2

[0118] -1.4 < TTL / f3 < 1.4

[0119] -1.0 < TTL / f4 < 1.0

[0120] 0.4 < BFL / f < 1.0

[0121] 0.9 < BFL / f1 < 2.1

[0122] -3.0 < BFL / f2 < -0.1

[0123] -1.0 < BFL / f3 < 1.0

[0124] -0.3 < BFL / f4 < 0.4

[0125] 5.0 mm < PID < 8.0 mm

[0126] 2.3 < PID / IMG HT < 6.0

[0127] In the above conditional expressions, f1 can denote a focal length of the first lens, f2 can denote a focal length of the second lens, f3 can denote a focal length of a lens disposed closest to the image side of the second lens (hereinafter referred to as a third lens), f4 can denote a focal length of a lens disposed closest to the image side of the third lens (hereinafter referred to as a fourth lens), PID can denote an optical path distance from an incident surface to an exit surface of an optical path folding member disposed closest to an imaging surface, and IMG HT can denote a height of the imaging surface.

[0128] If necessary, the imaging lens system according to the first to fourth exemplary embodiments can include one or more lenses having the following properties. For example, the imaging lens system according to the first exemplary embodiment can include one of the first to fourth lenses having the following properties. In another example, the imaging lens system according to the second exemplary embodiment can include two or more of the first to fourth lenses having the following properties. However, the imaging lens system according to the above exemplary embodiments can not necessarily include a lens having the following properties.

[0129] The first lens can have a refractive power. For example, the first lens can have a positive refractive power. The first lens can have one convex surface. For example, the first lens can have a convex object side surface. The first lens can have a predetermined refractive index. For example, the refractive index of the first lens can be 1.5 or more. As a specific example, the refractive index of the first lens can be greater than 1.5 and less than 1.6. The first lens can have a predetermined Abbe number. For example, the Abbe number of the first lens can be 50 or more. As a specific example, the Abbe number of the first lens can be greater than 52 and less than 62. The first lens can have a predetermined focal length. For example, the focal length of the first lens can be determined in the range of 7.6 mm to 10.0 mm.

[0130] The second lens can have a refractive power. For example, the second lens can have a negative refractive power. The second lens can have one convex surface. For example, the second lens can have a convex image side surface. The second lens can have a predetermined refractive index. For example, the refractive index of the second lens can be 1.6 or more. As a specific example, the refractive index of the second lens can be greater than 1.6 and less than 1.7. The second lens can have a predetermined Abbe number. For example, the Abbe number of the second lens can be 20 or more. As a specific example, the Abbe number of the second lens can be greater than 20 and less than 30. The second lens can have a predetermined focal length. For example, the focal length of the second lens can be determined in the range of -60 mm to -6.0 mm.

[0131] The third lens can have a refractive power. For example, the third lens can have a positive refractive power or a negative refractive power. The third lens can have one concave surface. For example, the third lens can have a concave image side surface. The third lens can have a predetermined refractive index. For example, the refractive index of the third lens can be 1.5 or more. As a specific example, the refractive index of the third lens can be greater than 1.5 and less than 1.7. The third lens can have a predetermined Abbe number. For example, the Abbe number of the third lens can be 18 or more. As a specific example, the Abbe number of the third lens can be greater than 18 and less than 60. The third lens can have a predetermined focal length. For example, the focal length of the third lens can be less than -10 mm or greater than 10 mm.

[0132] The fourth lens can have a refractive power. For example, the fourth lens can have a positive refractive power or a negative refractive power. The fourth lens can have one convex surface. For example, the fourth lens can have a convex object side surface. The fourth lens can have a predetermined refractive index. For example, the refractive index of the fourth lens can be 1.5 or more. As a specific example, the refractive index of the fourth lens can be greater than 1.5 and less than 1.6. The fourth lens can have a predetermined Abbe number. For example, the Abbe number of the fourth lens can be 50 or more. As a specific example, the Abbe number of the fourth lens can be greater than 50 and less than 60. The fourth lens can have a predetermined focal length. For example, the focal length of the fourth lens can be less than -20 mm or greater than 20 mm.

[0133] The aspheric surfaces of the first to fourth lenses can be represented by Equation 1. In Equation 1, "c" can represent the reciprocal of the radius of curvature of the corresponding lens, "k" can represent a conic constant, "r" can represent the distance from a specific point on the aspheric surface of the lens to the optical axis, "A to H" and "J" can represent aspheric constants, and "Z" (or SAG) can represent the height in the direction of the optical axis from the specific point on the aspheric surface of the lens to the vertex of the aspheric surface of the corresponding lens.

[0134] Equation 1

[0135]

[0136] The electronic device according to the first exemplary embodiment of the present disclosure can have a reduced thickness to facilitate portability or storage. For example, the electronic device according to the exemplary embodiment can be a smartphone, a laptop computer, or the like. The electronic device according to the exemplary embodiment can include a camera module having a long focal length while being capable of achieving high resolution. For example, the electronic device can be equipped with a camera module including one of the imaging lens systems according to the first to fourth exemplary embodiments described above. However, the imaging lens system included in the camera module can not be limited to the imaging lens systems according to the first to fourth exemplary embodiments described above.

[0137] The electronic device according to the second exemplary embodiment can include a camera module having a unique shape. For example, the camera module can include an image sensor disposed to have an inclination with respect to an output unit (e.g., a liquid crystal panel) of the electronic device. As a specific example, a board on which the image sensor is mounted can be disposed to have an inclination of 16 to 32 degrees with respect to the output unit of the electronic device.

[0138] Hereinafter, exemplary embodiments in the present disclosure will now be described in detail with reference to the accompanying drawings.

[0139] First, reference will be made to Figure 1An imaging lens system according to a first exemplary embodiment is described.

[0140] The imaging lens system 100 according to the present exemplary embodiment can include a lens group LG, a first prism P1, and a second prism P2. However, the components of the imaging lens system 100 are not limited to the above-described members. For example, the imaging lens system 100 can further include an optical filter IF and an imaging plane IP. The lens group LG, the first prism P1, and the second prism P2 can be sequentially arranged from the object side. For example, the lens group LG can be disposed on the object side of the first prism P1, and the second prism P2 can be disposed on the image side of the first prism P1. However, the lens group LG, the first prism P1, and the second prism P2 are not limited to the above-described arrangement. For example, the lens group LG can be disposed on the image side of the first prism P1, i.e., between the first prism P1 and the second prism P2.

[0141] Next, the above-described components are sequentially described.

[0142] The lens group LG can include a plurality of lenses. For example, the lens group LG can include a first lens 110, a second lens 120, and a third lens 130 sequentially arranged from the object side. The first lens 110 to the third lens 130 can be arranged at predetermined intervals. For example, the image side surface of the first lens 110 can not be in contact with the object side surface of the second lens 120, and the image side surface of the second lens 120 can not be in contact with the object side surface of the third lens 130. However, the first lens 110 to the third lens 130 can not necessarily be arranged not to be in contact with each other. For example, the image side surface of the first lens 110 can be in contact with the object side surface of the second lens 120, or the image side surface of the second lens 120 can be in contact with the object side surface of the third lens 130.

[0143] Next, characteristics of the first lens 110 to the third lens 130 are described.

[0144] The first lens 110 can have a refractive power. For example, the first lens 110 can have a positive refractive power. The first lens 110 can have a convex object side surface and a concave image side surface. The first lens 110 can have a spherical surface. For example, both surfaces of the first lens 110 can be spherical. The second lens 120 can have a refractive power. For example, the second lens 120 can have a negative refractive power. The second lens 120 can have a convex object side surface and a concave image side surface. The second lens 120 can have an aspherical surface. For example, both surfaces of the second lens 120 can be aspherical. The third lens 130 can have a refractive power. For example, the third lens 130 can have a positive refractive power. The third lens 130 can have a convex object side surface and a concave image side surface. The third lens 130 can have an aspherical surface. For example, both surfaces of the third lens 130 can be aspherical.

[0145] Next, the first prism P1 and the second prism P2 as the optical path folding members are described. As a reference, the prisms described below are one type of the optical path folding members described in the claims, and can be changed to another member.

[0146] The first prism P1 and the second prism P2 can be provided so that light incident through the first lens 110 to the third lens 130 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially provided between the third lens 130 and the imaging plane IP along the optical path.

[0147] The first prism P1 can have a triangular cross section. For example, a cross section of the first prism P1 cut in the direction of the optical path can have a right triangle shape. The incident surface S7 of the first prism P1 and the projection surface S9 of the first prism P1 can form a substantially right angle. For example, the incident surface S7 of the first prism P1 and the projection surface S9 of the first prism P1 can be formed in portions other than the hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0148] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S8. The first reflection surface S8 can achieve total reflection. For example, a first incident angle θ1 of the first reflection surface S8 can be greater than a critical angle of the first reflection surface S8. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S8. The first prism P1 configured as described above can reflect light incident from the third lens 130 as it is to the second prism P2.

[0149] The second prism P2 can have a triangular cross section. For example, a cross section of the second prism P2 cut in the direction of the optical path can have a right triangle shape. The second prism P2 can include a plurality of reflection surfaces. For example, the second prism P2 can include a second reflection surface S11 and a third reflection surface S12.

[0150] The second prism P2 can achieve total reflection and specular reflection. For example, the second reflection surface S11 of the second prism P2 can achieve total reflection, and the third reflection surface S12 of the second prism P2 can achieve specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflection surface S11 can be greater than a critical angle of the second reflection surface S11, and a third incident angle θ3 of the third reflection surface S12 can be less than a critical angle of the third reflection surface S12.

[0151] The second reflecting surface S11 and the third reflecting surface S12 can form an acute angle. For example, the angle θP2 between the second reflecting surface S11 and the third reflecting surface S12 can be 16 degrees to 32 degrees. The second reflecting surface S11 and the third reflecting surface S12 can each have a predetermined angle with the incident surface S10 of the second prism P2. For example, the angle between the second reflecting surface S11 and the incident surface S10 of the second prism P2 can be 58 degrees to 74 degrees, and the angle between the third reflecting surface S12 and the incident surface S10 of the second prism P2 can be about 90 degrees.

[0152] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S10 of the second prism P2 can be reflected by the second reflecting surface S11 and then reflected again by the third reflecting surface S12.

[0153] One surface of the second prism P2 can implement both reflection and projection. For example, the second reflecting surface S11 of the second prism P2 can transmit light incident from the third reflecting surface S12 while reflecting light incident through the incident surface S10 to the third reflecting surface S12.

[0154] The first reflecting surface S8, the second reflecting surface S11, and the third reflecting surface S12 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship. For example, the first incident angle θ1 can be smaller than the second incident angle θ2, and the third incident angle θ3 can be smaller than the first incident angle θ1.

[0155] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 100 by folding the optical path from the object side to the imaging plane IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 100 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 100 in the direction of the second optical axis C2.

[0156] The optical filter IF and the imaging plane IP can be disposed on one side of the second prism P2. For example, the optical filter IF and the imaging plane IP can be disposed to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the optical filter IF and the imaging plane IP can be disposed to face the second reflecting surface S11 of the second prism P2.

[0157] The optical filter IF can block light of a specific wavelength. For example, the optical filter IF according to the present exemplary embodiment can block infrared light. However, the type of light blocked by the optical filter IF is not limited to infrared light. For example, the optical filter IF can block ultraviolet light or visible light.

[0158] The imaging plane IP can be located at a point at which light reflected by the third reflecting surface S12 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging plane IP can be formed on or inside the image sensor IS.

[0159] The imaging lens system 100 configured as above can exhibit aberration characteristics as shown in Table 1 and Table 2, respectively. Figure 2

[0160] Table 1

[0161]

[0162]

[0163] Table 2

[0164] Surface Number S1 S2 S3 S4 S5 S6 k 0 0 3.847E+01 2.078E-01 -6.915E-01 9.200E+00 A 0 0 1.319E-02 1.729E-02 5.342E-03 1.012E-03 B 0 0 1.377E-03 -7.004E-04 -2.741E-04 -2.020E-04 C 0 0 3.400E-04 -1.445E-04 2.866E-05 -7.257E-05 D 0 0 3.735E-04 1.419E-04 -3.251E-05 -1.573E-04 E 0 0 0 0 0 0 F 0 0 0 0 0 0 G 0 0 0 0 0 0 H 0 0 0 0 0 0 J 0 0 0 0 0 0

[0165] Next, a modified example of the imaging lens system according to the first exemplary embodiment will be described with reference to Figure 3 and Figure 4 As a reference, in the following description, components that are the same as those of the above-described exemplary embodiment are denoted by the same reference numerals as those of the above-described exemplary embodiment, and detailed description of these components is omitted.

[0166] First, the imaging lens system 101 according to the first modified example will be described with reference to Figure 3

[0167] The imaging lens system 101 according to the first modified example can include a light path folding member P in which a first prism and a second prism are integrally formed with each other as shown in Figure 3 For example, the light path folding member P can have a first prism P1 and a second prism P2 combined with each other. Figure 1

[0168] The light path folding member P can include three reflecting surfaces. For example, the light path folding member P can include a first reflecting surface PS1, a second reflecting surface PS2, and a third reflecting surface PS3. The first reflecting surface PS1, the second reflecting surface PS2, and the third reflecting surface PS3 can be arranged in order along the optical path.

[0169] ​​​The light path folding member P can implement both total reflection and mirror reflection (or specular reflection). For example, the first reflecting surface PS1 and the second reflecting surface PS2 can implement total reflection, and the third reflecting surface PS3 can implement mirror reflection.

[0170] The first reflecting surface PS1, the second reflecting surface PS2, and the third reflecting surface PS3 can each have a predetermined angle of incidence. For example, a first angle of incidence θ1 of the first reflecting surface PS1 can be 45 degrees, a second angle of incidence θ2 of the second reflecting surface PS2 can be 60 degrees, and a third angle of incidence θ3 of the third reflecting surface PS3 can be 30 degrees.

[0171] The imaging lens system 101 configured as described above can replace a plurality of prisms with one light path folding member P, thereby simplifying an assembly process of the imaging lens system 101.

[0172] Next, referring to Figure 4 An imaging lens system 102 according to a second modified example is described.

[0173] The imaging lens system 102 according to the second modified example can implement a relatively long back focal length. For example, the imaging lens system 102 according to the modified example can include a second prism P2 that enables two or more times of internal reflection as illustrated in Figure 4 As a specific example, the second prism P2 can implement four times of internal reflection. For reference, an angle θP2 between the second reflecting surface S11 and the third reflecting surface S12 can be 18 degrees.

[0174] The imaging lens system 102 configured as described above can have a back focal length increased by the multiple times of internal reflection implemented by the second prism P2 as described above, thereby improving a telephoto characteristic of the imaging lens system 102.

[0175] Next, referring to Figure 5 An imaging lens system according to a second exemplary embodiment is described.

[0176] The imaging lens system 200 according to the present exemplary embodiment can include a lens group LG, a first prism P1, and a second prism P2. However, the components of the imaging lens system 200 are not limited to the above-described members. For example, the imaging lens system 200 can further include an optical filter IF and an imaging plane IP. The lens group LG, the first prism P1, and the second prism P2 can be sequentially arranged from an object side. For example, the lens group LG can be disposed on an object side of the first prism P1, and the second prism P2 can be disposed on an image side of the first prism P1. However, the lens group LG, the first prism P1, and the second prism P2 are not limited to the above-described arrangement. For example, the lens group LG can be disposed on an image side of the first prism P1, i.e., between the first prism P1 and the second prism P2.

[0177] Next, the above-described components are sequentially described.

[0178] The lens group LG can include a plurality of lenses. For example, the lens group LG can include a first lens 210, a second lens 220, and a third lens 230 sequentially disposed from an object side. The first lens 210 to the third lens 230 can be disposed at a predetermined interval. For example, an image side surface of the first lens 210 can not be in contact with an object side surface of the second lens 220, and an image side surface of the second lens 220 can not be in contact with an object side surface of the third lens 230. However, the first lens 210 to the third lens 230 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the first lens 210 can be in contact with the object side surface of the second lens 220, or the image side surface of the second lens 220 can be in contact with the object side surface of the third lens 230.

[0179] Next, characteristics of the first lens 210 to the third lens 230 are described.

[0180] The first lens 210 can have a refractive power. For example, the first lens 210 can have a positive refractive power. The first lens 210 can have a convex object side surface and a convex image side surface. The first lens 210 can have a spherical surface. For example, both surfaces of the first lens 210 can be spherical. The second lens 220 can have a refractive power. For example, the second lens 220 can have a negative refractive power. The second lens 220 can have a convex object side surface and a concave image side surface. The second lens 220 can have an aspherical surface. For example, both surfaces of the second lens 220 can be aspherical. The third lens 230 can have a refractive power. For example, the third lens 230 can have a positive refractive power. The third lens 230 can have a convex object side surface and a concave image side surface. The third lens 230 can have an aspherical surface. For example, both surfaces of the third lens 230 can be aspherical.

[0181] Next, the first prism P1 and the second prism P2 as the optical path folding member are described. As a reference, the prisms described below are one type of the optical path folding member described in the claims, and can be changed to another member.

[0182] The first prism P1 and the second prism P2 can be disposed such that light incident through the first lens 210 to the third lens 230 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially disposed between the third lens 230 and the imaging plane IP along an optical path.

[0183] The first prism P1 can have a triangular cross-section. For example, a cross-section of the first prism P1 cut in a direction of an optical path can have a right triangle shape. An incident surface S7 of the first prism P1 and a projection surface S9 of the first prism P1 can form a substantially right angle. For example, the incident surface S7 of the first prism P1 and the projection surface S9 of the first prism P1 can be formed in portions other than a hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0184] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S8. The first reflection surface S8 can implement total reflection. For example, a first incident angle θ1 of the first reflection surface S8 can be greater than a critical angle of the first reflection surface S8. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S8. The first prism P1 configured as described above can reflect light incident from the third lens 230 as it is to the second prism P2.

[0185] The second prism P2 can have a triangular cross-section. For example, a cross-section of the second prism P2 cut in a direction of an optical path can have a right triangle shape. The second prism P2 can include a plurality of reflection surfaces. For example, the second prism P2 can include a second reflection surface S11 and a third reflection surface S12.

[0186] The second prism P2 can implement total reflection and specular reflection. For example, the second reflection surface S11 of the second prism P2 can implement total reflection, and the third reflection surface S12 of the second prism P2 can implement specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflection surface S11 can be greater than a critical angle of the second reflection surface S11, and a third incident angle θ3 of the third reflection surface S12 can be less than a critical angle of the third reflection surface S12.

[0187] The second reflection surface S11 and the third reflection surface S12 can form an acute angle. For example, an angle θP2 between the second reflection surface S11 and the third reflection surface S12 can be 16 degrees to 32 degrees. The second reflection surface S11 and the third reflection surface S12 can have a predetermined angle with an incident surface S10 of the second prism P2. For example, an angle between the second reflection surface S11 and the incident surface S10 of the second prism P2 can be 58 degrees to 74 degrees, and an angle between the third reflection surface S12 and the incident surface S10 of the second prism P2 can be about 90 degrees.

[0188] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S10 of the second prism P2 can be reflected by the second reflection surface S11 and then reflected again by the third reflection surface S12.

[0189] One surface of the second prism P2 can achieve both reflection and projection. For example, the second reflection surface S11 of the second prism P2 can transmit light incident from the third reflection surface S12 while reflecting light incident through the incidence surface S10 to the third reflection surface S12.

[0190] The first reflection surface S8, the second reflection surface S11, and the third reflection surface S12 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship therebetween. For example, the first incidence angle θ1 can be smaller than the second incidence angle θ2, and the third incidence angle θ3 can be smaller than the first incidence angle θ1.

[0191] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 200 by folding the optical path from the object side to the imaging plane IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 200 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 200 in the direction of the second optical axis C2.

[0192] The imaging plane IP can be disposed on one side of the second prism P2. For example, the imaging plane IP can be disposed to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the imaging plane IP can be disposed to face the second reflection surface S11 of the second prism P2.

[0193] The imaging plane IP can be located at a point at which light reflected by the third reflection surface S12 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging plane IP can be formed on or inside the image sensor IS.

[0194] In the imaging lens system 200 according to the present exemplary embodiment, a filter (not shown) can be integrally formed on one surface of the second prism P2. For example, the filter can be integrally formed on the incidence surface S10 or the projection surface S11 of the second prism P2. As a specific example, the filter can be manufactured in the shape of a film, and attached to the incidence surface S10 or the projection surface S11 of the second prism P2.

[0195] The imaging lens system 200 configured as described above can exhibit aberration characteristics as shown in Table 1. Figure 6 Table 1 shows lens characteristics and aspherical values of the imaging lens system according to the present exemplary embodiment.

[0196] Table 3

[0197]

[0198]

[0199] Table 4

[0200] Surface Number S1 S2 S3 S4 S5 S6 k 0 0 3.981E+01 2.311E-01 -2.494E+00 7.892E+01 A 0 0 1.268E-02 1.661E-02 7.014E-03 -4.885E-03 B 0 0 1.083E-03 -1.451E-04 -5.181E-04 -7.813E-04 C 0 0 2.509E-05 5.160E-04 3.048E-05 3.334E-04 D 0 0 4.678E-04 7.040E-07 8.988E-06 -5.540E-04 E 0 0 0 0 0 0 F 0 0 0 0 0 0 G 0 0 0 0 0 0 H 0 0 0 0 0 0 J 0 0 0 0 0 0

[0201] Next, referring to Figure 7 An imaging lens system according to a third exemplary embodiment is described.

[0202] The imaging lens system 300 according to the present exemplary embodiment can include a first lens group LG1, a first prism P1, a second lens group LG2, and a second prism P2. However, the components of the imaging lens system 300 are not limited to the above-described members. For example, the imaging lens system 300 can further include an optical filter IF and an imaging plane IP. The first lens group LG1, the first prism P1, the second lens group LG2, and the second prism P2 can be sequentially arranged from the object side. For example, the first lens group LG1 can be disposed on the object side of the first prism P1, and the second lens group LG2 can be disposed between the first prism P1 and the second prism P2.

[0203] Next, the above-described components are described in order.

[0204] The first lens group LG1 can include a plurality of lenses. For example, the first lens group LG1 can include a first lens 310, a second lens 320, and a third lens 330 sequentially arranged from the object side. The first lens 310 to the third lens 330 can be arranged at predetermined intervals. For example, the image side surface of the first lens 310 can not be in contact with the object side surface of the second lens 320, and the image side surface of the second lens 320 can not be in contact with the object side surface of the third lens 330. However, the first lens 310 to the third lens 330 can not necessarily be arranged not to be in contact with each other. For example, the image side surface of the first lens 310 can be in contact with the object side surface of the second lens 320, or the image side surface of the second lens 320 can be in contact with the object side surface of the third lens 330.

[0205] The second lens group LG2 can include one or more lenses. For example, the second lens group LG2 can include a fourth lens 340. However, the lens included in the second lens group LG2 is not limited to the fourth lens 340. For example, the second lens group LG2 can further include a lens or can include the above-described optical filter IF.

[0206] Next, characteristics of the first lens 310 to the fourth lens 340 included in the first lens group LG1 and the second lens group LG2 are described.

[0207] The first lens 310 can have a refractive power. For example, the first lens 310 can have a positive refractive power. The first lens 310 can have a convex object side surface and a convex image side surface. The first lens 310 can have a spherical surface. For example, both surfaces of the first lens 310 can be spherical. The second lens 320 can have a refractive power. For example, the second lens 320 can have a negative refractive power. The second lens 320 can have a convex object side surface and a concave image side surface. The second lens 320 can have an aspherical surface. For example, both surfaces of the second lens 320 can be aspherical. The third lens 330 can have a refractive power. For example, the third lens 330 can have a positive refractive power. The third lens 330 can have a convex object side surface and a concave image side surface. The third lens 330 can have an aspherical surface. For example, both surfaces of the third lens 330 can be aspherical. The fourth lens 340 can have a refractive power. For example, the fourth lens 340 can have a positive refractive power. The fourth lens 340 can have a convex object side surface and a convex image side surface. The fourth lens 340 can have a spherical surface. For example, both surfaces of the fourth lens 340 can be spherical.

[0208] Next, the first prism P1 and the second prism P2 as the optical path folding members are described. As a reference, the prisms described below are one type of the optical path folding members described in the claims, and can be changed to another member.

[0209] The first prism P1 and the second prism P2 can be disposed so that light incident through the first lens 310 to the fourth lens 340 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially disposed between the third lens 330 and the imaging plane IP along the optical path.

[0210] The first prism P1 can have a triangular cross section. For example, a cross section of the first prism P1 cut in the direction of the optical path can have a right triangle shape. The incident surface S7 of the first prism P1 and the projection surface S9 of the first prism P1 can form a substantially right angle. For example, the incident surface S7 of the first prism P1 and the projection surface S9 of the first prism P1 can be formed in portions other than the hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0211] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S8. The first reflection surface S8 can achieve total reflection. For example, a first incident angle θ1 of the first reflection surface S8 can be greater than a critical angle of the first reflection surface S8. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S8. The first prism P1 configured as described above can reflect light incident from the third lens 330 as it is to the second prism P2.

[0212] The second prism P2 can have a triangular cross-section. For example, a cross-section of the second prism P2 cut in the optical path direction can have a right triangle shape. The second prism P2 can include a plurality of reflective surfaces. For example, the second prism P2 can include a second reflective surface S13 and a third reflective surface S14.

[0213] The second prism P2 can implement total reflection and specular reflection. For example, the second reflective surface S13 of the second prism P2 can implement total reflection, and the third reflective surface S14 of the second prism P2 can implement specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflective surface S13 can be greater than a critical angle of the second reflective surface S13, and a third incident angle θ3 of the third reflective surface S14 can be less than a critical angle of the third reflective surface S14.

[0214] The second reflective surface S13 and the third reflective surface S14 can form an acute angle. For example, an angle θP2 between the second reflective surface S13 and the third reflective surface S14 can be 16 degrees to 32 degrees. The second reflective surface S13 and the third reflective surface S14 can have a predetermined angle with the incident surface S12 of the second prism P2. For example, an angle between the second reflective surface S13 and the incident surface S12 of the second prism P2 can be 58 degrees to 74 degrees, and an angle between the third reflective surface S14 and the incident surface S12 of the second prism P2 can be about 90 degrees.

[0215] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S12 of the second prism P2 can be reflected by the second reflective surface S13 and then reflected again by the third reflective surface S14.

[0216] One surface of the second prism P2 can implement both reflection and projection. For example, the second reflective surface S13 of the second prism P2 can transmit light incident from the third reflective surface S14 while reflecting light incident through the incident surface S12 to the third reflective surface S14.

[0217] The first reflective surface S8, the second reflective surface S13, and the third reflective surface S14 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship. For example, the first incident angle θ1 can be less than the second incident angle θ2, and the third incident angle θ3 can be less than the first incident angle θ1.

[0218] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 300 by folding the optical path connecting from the object side to the imaging surface IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 300 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 300 in the direction of the second optical axis C2.

[0219] The optical filter IF and the imaging surface IP can be provided on one side of the second prism P2. For example, the optical filter IF and the imaging surface IP can be provided to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the optical filter IF and the imaging surface IP can be provided to face the second reflecting surface S13 of the second prism P2.

[0220] The optical filter IF can block light of a specific wavelength. For example, the optical filter IF according to the present exemplary embodiment can block infrared light. However, the type of light blocked by the optical filter IF is not limited to infrared light. For example, the optical filter IF can block ultraviolet light or visible light.

[0221] The imaging surface IP can be located at a point at which light reflected by the third reflecting surface S14 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging surface IP can be formed on or inside the image sensor IS.

[0222] The imaging lens system 300 configured as described above can exhibit aberration characteristics as shown. Figure 8 Tables 5 and 6 show the lens characteristics and aspherical values of the imaging lens system according to the present exemplary embodiment, respectively.

[0223] Table 5

[0224]

[0225]

[0226] Table 6

[0227] Surface Number S1 S2 S3 S4 S5 S6 S10 S11 k 0 0 4.25E+01 2.17E-01 -2.54E+00 7.89E+01 0 0 A 0 0 1.16E-02 1.74E-02 7.08E-03 -5.72E-03 0 0 B 0 0 1.27E-03 -1.72E-04 -3.46E-04 -1.85E-03 0 0 C 0 0 6.76E-05 2.88E-04 5.74E-06 5.10E-04 0 0 D 0 0 3.68E-04 3.51E-04 1.05E-04 -3.12E-04 0 0 E 0 0 0 0 0 0 0 0 F 0 0 0 0 0 0 0 0 G 0 0 0 0 0 0 0 0 H 0 0 0 0 0 0 0 0 J 0 0 0 0 0 0 0 0

[0228] Next, reference will be made to Figure 9 and Figure 10A modified example of the imaging lens system according to the third exemplary embodiment is described. For reference, in the following description, components that are the same as those of the above-described exemplary embodiments are denoted by the same reference numerals as those of the above-described exemplary embodiments, and detailed description of these components is omitted.

[0229] First, reference is made to Figure 9 An imaging lens system 301 according to a first modified example is described.

[0230] The imaging lens system 301 according to the first modified example can further include a third prism P3. For example, the imaging lens system 301 can further include the third prism P3 disposed between the second lens group LG2 and the second prism P2.

[0231] The third prism P3 can include a reflective surface. For example, the third prism P3 can include one reflective surface P3SR. The reflective surface P3SR of the third prism P3 can achieve total reflection. For example, an incident angle of the reflective surface P3SR can be greater than a critical angle of the reflective surface P3SR. The third prism P3 can have a shape that is substantially the same as or similar to a shape of the first prism PI. However, the first prism PI and the third prism P3 can not necessarily have the same or similar shapes.

[0232] The imaging lens system 301 configured as described above can have an easy-extended back focal length (BFL, i.e., a distance from an image-side surface of the fourth lens 340 to the imaging plane IP) without deforming the second prism P2 to have Figure 4 the shape shown.

[0233] Next, reference is made to Figure 10 An imaging lens system 302 according to a second modified example is described.

[0234] The imaging lens system 302 according to the second modified example can further include a third prism P3 and a fourth prism P4. For example, the imaging lens system 302 can further include the third prism P3 disposed between the first prism PI and the second lens group LG2 and the fourth prism P4 disposed between the second lens group LG2 and the second prism P2.

[0235] The third prism P3 can include a reflective surface. For example, the third prism P3 can include one reflective surface P3SR. The reflective surface P3SR of the third prism P3 can achieve total reflection. For example, an incident angle of the reflective surface P3SR can be greater than a critical angle of the reflective surface P3SR. The third prism P3 can have a shape that is substantially the same as or similar to a shape of the first prism PI. However, the first prism PI and the third prism P3 can not necessarily have the same or similar shapes.

[0236] The fourth prism P4 can include a reflective surface. For example, the fourth prism P4 can include one reflective surface P4SR. The reflective surface P4SR of the fourth prism P4 can implement total reflection. For example, an incident angle of the reflective surface P4SR can be greater than a critical angle of the reflective surface P4SR. The fourth prism P4 can have a shape which is substantially the same as or similar to a shape of the first prism P1 or the third prism P3. However, the fourth prism P4 can not necessarily have the same or similar shape as the first prism P1 or the third prism P3.

[0237] The imaging lens system 302 configured as described above can have an integrated arrangement of the plurality of lens groups LG1 and LG2 and the imaging plane IP within a limited space by the plurality of prisms P1, P2, P3, and P4, and thus can be easily mounted in an electronic device (e.g., a portable terminal) having a narrow mounting space.

[0238] Next, referring to Figure 11 An imaging lens system according to a fourth exemplary embodiment is described.

[0239] The imaging lens system 400 according to the present exemplary embodiment can include a first lens group LG1, a first prism P1, a second lens group LG2, and a second prism P2. However, the components of the imaging lens system 400 are not limited to the above-described members. For example, the imaging lens system 400 can further include a filter IF and an imaging plane IP. The first lens group LG1, the first prism P1, the second lens group LG2, and the second prism P2 can be sequentially arranged from an object side. For example, the first lens group LG1 can be disposed on an object side of the first prism P1, and the second lens group LG2 can be disposed between the first prism P1 and the second prism P2.

[0240] Next, the above-described components are sequentially described.

[0241] The first lens group LG1 can include a plurality of lenses. For example, the first lens group LG1 can include a first lens 410 and a second lens 420 sequentially disposed from an object side. The first lens 410 and the second lens 420 can be disposed at a predetermined interval. For example, an image side surface of the first lens 410 can not be in contact with an object side surface of the second lens 420. However, the first lens 410 and the second lens 420 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the first lens 410 can be in contact with the object side surface of the second lens 420.

[0242] The second lens group LG2 can include one or more lenses. For example, the second lens group LG2 can include a third lens 430. However, the lens included in the second lens group LG2 is not limited to the third lens 430.

[0243] Next, characteristics of the first lens 410 to the third lens 430 included in the first lens group LG1 and the second lens group LG2 are described.

[0244] The first lens 410 can have a refractive power. For example, the first lens 410 can have a positive refractive power. The first lens 410 can have a convex object side surface and a convex image side surface. The first lens 410 can have a spherical surface. For example, both surfaces of the first lens 410 can be spherical. The second lens 420 can have a refractive power. For example, the second lens 420 can have a negative refractive power. The second lens 420 can have a convex object side surface and a concave image side surface. The second lens 420 can have an aspherical surface. For example, both surfaces of the second lens 420 can be aspherical. The third lens 430 can have a refractive power. For example, the third lens 430 can have a positive refractive power. The third lens 430 can have a convex object side surface and a concave image side surface. The third lens 430 can have a spherical surface and an aspherical surface. For example, the object side surface of the third lens 430 can be spherical, and the image side surface of the third lens 430 can be aspherical.

[0245] Next, the first prism P1 and the second prism P2 as the optical path folding member are described. As a reference, the prisms described below are one type of the optical path folding member described in the claims, and can be changed to another member.

[0246] The first prism P1 and the second prism P2 can be disposed so that light incident through the first lens 410 to the third lens 430 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially disposed between the second lens 420 and the imaging plane IP along the optical path.

[0247] The first prism P1 can have a triangular cross section. For example, a cross section of the first prism P1 cut in the direction of the optical path can have a right triangle shape. The incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can form a substantially right angle. For example, the incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can be formed in portions other than the hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0248] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S6. The first reflection surface S6 can implement total reflection. For example, a first incident angle θ1 of the first reflection surface S6 can be greater than a critical angle of the first reflection surface S6. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S6. The first prism P1 configured as described above can reflect light incident from the second lens 420 to the third lens 430 and the second prism P2.

[0249] The second prism P2 can have a triangular cross-section. For example, a cross-section of the second prism P2 cut in the optical path direction can have a right triangle shape. The second prism P2 can include a plurality of reflective surfaces. For example, the second prism P2 can include a second reflective surface S11 and a third reflective surface S12.

[0250] The second prism P2 can implement total reflection and specular reflection. For example, the second reflective surface S11 of the second prism P2 can implement total reflection, and the third reflective surface S12 of the second prism P2 can implement specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflective surface S11 can be greater than a critical angle of the second reflective surface S11, and a third incident angle θ3 of the third reflective surface S12 can be less than a critical angle of the third reflective surface S12.

[0251] The second reflective surface S11 and the third reflective surface S12 can form an acute angle. For example, an angle θP2 between the second reflective surface S11 and the third reflective surface S12 can be 16 to 32 degrees. The second reflective surface S11 and the third reflective surface S12 can have a predetermined angle with the incident surface S10 of the second prism P2. For example, an angle between the second reflective surface S11 and the incident surface S10 of the second prism P2 can be 58 to 74 degrees, and an angle between the third reflective surface S12 and the incident surface S10 of the second prism P2 can be about 90 degrees.

[0252] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S10 of the second prism P2 can be reflected by the second reflective surface S11 and then reflected again by the third reflective surface S12.

[0253] One surface of the second prism P2 can implement both reflection and projection. For example, the second reflective surface S11 of the second prism P2 can transmit light incident from the third reflective surface S12 while reflecting light incident through the incident surface S10 to the third reflective surface S12.

[0254] The first reflective surface S6, the second reflective surface S11, and the third reflective surface S12 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship. For example, the first incident angle θ1 can be less than the second incident angle θ2, and the third incident angle θ3 can be less than the first incident angle θ1.

[0255] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 400 by folding the optical path connecting from the object side to the imaging surface IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 400 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 400 in the direction of the second optical axis C2.

[0256] The optical filter IF and the imaging surface IP can be disposed on one side of the second prism P2. For example, the optical filter IF and the imaging surface IP can be disposed to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the optical filter IF and the imaging surface IP can be disposed to face the second reflecting surface S11 of the second prism P2.

[0257] The optical filter IF can block light of a specific wavelength. For example, the optical filter IF according to the present exemplary embodiment can block infrared light. However, the type of light blocked by the optical filter IF is not limited to infrared light. For example, the optical filter IF can block ultraviolet light or visible light.

[0258] The imaging surface IP can be located at a point at which light reflected by the third reflecting surface S12 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging surface IP can be formed on or inside the image sensor IS.

[0259] The imaging lens system 400 configured as described above can exhibit aberration characteristics as shown in Table 7 and Table 8, respectively. Figure 12 Table 7 and Table 8 show the lens characteristics and aspherical values of the imaging lens system according to the present exemplary embodiment, respectively.

[0260] Table 7

[0261] Surface Number Component Radius of Curvature Thickness / Distance Refractive Index Abbe Number S1 First Lens 4.6702 1.300 1.537 55.7 S2 -42.9801 0.391 S3 Second Lens 18.0341 0.631 1.646 23.5 S4 4.3778 1.000 S5 First Prism Infinity 2.200 1.519 64.2 S6 Infinity 2.200 1.519 64.2 S7 Infinity 2.200 S8 Third Lens 5.5645 0.700 1.537 55.7 S9 14.1348 1.000 S10 Second Prism Infinity 3.500 1.519 64.2 S11 Infinity 2.500 1.519 64.2 S12 Infinity 1.250 1.519 64.2 S11 Infinity 0.500 S13 Filter Infinity 0.210 1.519 64.2 S14 Infinity 0.479 S15 Imaging Surface Infinity 0.000

[0262] Table 8

[0263] Surface Number S1 S2 S3 S4 S8 S9 k 0 0 3.81E+01 4.58E-01 0 -2.0E+00 A 0 0 1.55E-02 9.45E-03 0 6.0E-04 B 0 0 7.11E-04 1.42E-03 0 -2.8E-05 C 0 0 5.93E-04 2.08E-04 0 5.4E-05 D 0 0 1.58E-04 3.24E-04 0 -3.4E-06 E 0 0 1.12E-04 1.02E-04 0 -2.7E-06 F 0 0 -1.92E-05 -2.22E-05 0 -1.6E-07 G 0 0 1.03E-04 1.54E-04 0 1.3E-07 H 0 0 0 0 0 3.0E-08 J 0 0 0 0 0 -8.4E-09

[0264] Next, an imaging lens system according to a fifth exemplary embodiment will be described with reference to Figure 13

[0265] ​The imaging lens system 500 according to the present exemplary embodiment can include a first lens group LG1, a first prism P1, a second lens group LG2, and a second prism P2. However, the components of the imaging lens system 500 are not limited to the above-described members. For example, the imaging lens system 500 can further include an optical filter IF and an imaging plane IP. The first lens group LG1, the first prism P1, the second lens group LG2, and the second prism P2 can be sequentially arranged from the object side. For example, the first lens group LG1 can be disposed on the object side of the first prism P1, and the second lens group LG2 can be disposed between the first prism P1 and the second prism P2.

[0266] Next, the above-described components are sequentially described.

[0267] The first lens group LG1 can include a plurality of lenses. For example, the first lens group LG1 can include a first lens 510 and a second lens 520 sequentially disposed from the object side. The first lens 510 and the second lens 520 can be disposed at a predetermined interval. For example, the image side surface of the first lens 510 can not be in contact with the object side surface of the second lens 520. However, the first lens 510 and the second lens 520 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the first lens 510 can be in contact with the object side surface of the second lens 520.

[0268] The second lens group LG2 can include one or more lenses. For example, the second lens group LG2 can include a third lens 530. However, the lens included in the second lens group LG2 is not limited to the third lens 530.

[0269] Next, characteristics of the first lens 510 to the third lens 530 included in the first lens group LG1 and the second lens group LG2 are described.

[0270] The first lens 510 can have a refractive power. For example, the first lens 510 can have a positive refractive power. The first lens 510 can have a convex object side surface and a convex image side surface. The first lens 510 can have a spherical surface. For example, both surfaces of the first lens 510 can be spherical. The second lens 520 can have a refractive power. For example, the second lens 520 can have a negative refractive power. The second lens 520 can have a convex object side surface and a concave image side surface. The second lens 520 can have an aspherical surface. For example, both surfaces of the second lens 520 can be aspherical. The third lens 530 can have a refractive power. For example, the third lens 530 can have a negative refractive power. The third lens 530 can have a convex object side surface and a concave image side surface. The third lens 530 can have a spherical surface and an aspherical surface. For example, the object side surface of the third lens 530 can be spherical, and the image side surface of the third lens 530 can be aspherical.

[0271] Next, the first prism P1 and the second prism P2 as the optical path folding members are described. As a reference, the prisms described below are one type of the optical path folding members described in the claims, and can be changed to another member.

[0272] The first prism P1 and the second prism P2 can be provided so that light incident through the first lens 510 to the third lens 530 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially provided between the second lens 520 and the imaging plane IP along the optical path.

[0273] The first prism P1 can have a triangular cross section. For example, a cross section of the first prism P1 cut in the direction of the optical path can have a right triangle shape. The incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can form a substantially right angle. For example, the incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can be formed in portions other than the hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0274] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S6. The first reflection surface S6 can achieve total reflection. For example, a first incident angle θ1 of the first reflection surface S6 can be greater than a critical angle of the first reflection surface S6. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S6. The first prism P1 configured as described above can reflect light incident from the second lens 520 to the third lens 530 and the second prism P2.

[0275] The second prism P2 can have a triangular cross section. For example, a cross section of the second prism P2 cut in the direction of the optical path can have a right triangle shape. The second prism P2 can include a plurality of reflection surfaces. For example, the second prism P2 can include a second reflection surface S11 and a third reflection surface S12.

[0276] The second prism P2 can achieve total reflection and specular reflection. For example, the second reflection surface S11 of the second prism P2 can achieve total reflection, and the third reflection surface S12 of the second prism P2 can achieve specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflection surface S11 can be greater than a critical angle of the second reflection surface S11, and a third incident angle θ3 of the third reflection surface S12 can be less than a critical angle of the third reflection surface S12.

[0277] The second reflecting surface S11 and the third reflecting surface S12 can form an acute angle. For example, an angle θP2 between the second reflecting surface S11 and the third reflecting surface S12 can be 16 degrees to 32 degrees. The second reflecting surface S11 and the third reflecting surface S12 can have predetermined angles with the incident surface S10 of the second prism P2. For example, an angle between the second reflecting surface S11 and the incident surface S10 of the second prism P2 can be 58 degrees to 74 degrees, and an angle between the third reflecting surface S12 and the incident surface S10 of the second prism P2 can be about 90 degrees.

[0278] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S10 of the second prism P2 can be reflected by the second reflecting surface S11 and then reflected again by the third reflecting surface S12.

[0279] One surface of the second prism P2 can implement both reflection and projection. For example, the second reflecting surface S11 of the second prism P2 can transmit light incident from the third reflecting surface S12 while reflecting light incident through the incident surface S10 to the third reflecting surface S12.

[0280] The first reflecting surface S6, the second reflecting surface S11, and the third reflecting surface S12 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship. For example, the first incident angle θ1 can be smaller than the second incident angle θ2, and the third incident angle θ3 can be smaller than the first incident angle θ1.

[0281] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 500 by folding an optical path from the object side to the imaging plane IP. For example, the first prism P1 can fold an optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 500 in the direction of the first optical axis C1. In another example, the second prism P2 can fold an optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 500 in the direction of the second optical axis C2.

[0282] The filter IF and the imaging plane IP can be disposed on one side of the second prism P2. For example, the filter IF and the imaging plane IP can be disposed to face a hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the filter IF and the imaging plane IP can be disposed to face the second reflecting surface S11 of the second prism P2.

[0283] A filter IF can block light of a specific wavelength. For example, a filter IF according to this exemplary embodiment can block infrared light. However, the type of light blocked by the filter IF is not limited to infrared light. For example, a filter IF can block ultraviolet light or visible light.

[0284] The imaging surface IP can be located at the point where the light reflected by the third reflecting surface S12 converges or forms an image, and can be formed by an image sensor IS, etc. For example, the imaging surface IP can be formed on or inside the image sensor IS.

[0285] The imaging lens system 500 configured as described above can display... Figure 14 The aberration characteristics are shown. Tables 9 and 10 respectively show the lens characteristics and aspherical values ​​of the imaging lens system according to this exemplary embodiment.

[0286] Table 9

[0287] Surface Number Component Radius of Curvature Thickness / Distance Refractive Index Abbe Number S1 First Lens 5.5237 1.000 1.537 55.7 S2 -25.1115 0.050 S3 Second Lens 13.5896 0.400 1.646 23.5 S4 7.0152 0.800 S5 First Prism Infinity 1.600 1.519 64.2 S6 Infinity 1.600 1.519 64.2 S7 Infinity 2.500 S8 Third Lens 16.0727 0.400 1.537 55.7 S9 10.7448 1.500 S10 Fourth Lens Second Prism 3.000 1.519 64.2 S11 Infinity 2.000 1.519 64.2 S12 Infinity 1.000 1.519 64.2 S11 Infinity 0.500 S13 Infinity Filter 0.210 1.519 64.2 S14 Infinity 0.236 S15 Infinity Imaging Surface 0.066

[0288] Table 10

[0289] Infinity S1 S2 S3 S4 S8 S9 k 0 0 3.26E+01 1.15E+00 0 2.0E+01 A 0 0 1.37E-02 5.12E-03 0 2.1E-03 B 0 0 -8.93E-04 1.42E-03 0 3.0E-04 C 0 0 7.69E-04 5.53E-04 0 1.0E-04 D 0 0 7.84E-04 7.76E-04 0 5.2E-05 E 0 0 -1.57E-04 6.40E-05 0 3.8E-05 F 0 0 -7.69E-06 4.97E-05 0 2.2E-05 G 0 0 -8.42E-06 -2.76E-05 0 1.6E-06 H 0 0 0 0 0 0 J 0 0 0 0 0 0

[0290] Next, refer to Surface Number An imaging lens system according to a sixth exemplary embodiment is described.

[0291] The imaging lens system 600 according to this exemplary embodiment may include a first lens group LG1, a first prism P1, a second lens group LG2, and a second prism P2. However, the components of the imaging lens system 600 are not limited to the above-described components. For example, the imaging lens system 600 may also include a filter IF and an imaging plane IP. The first lens group LG1, the first prism P1, the second lens group LG2, and the second prism P2 may be arranged sequentially from the object side. For example, the first lens group LG1 may be disposed on the object side of the first prism P1, and the second lens group LG2 may be disposed between the first prism P1 and the second prism P2.

[0292] Next, the above components will be described in turn.

[0293] The first lens group LG1 may include multiple lenses. For example, the first lens group LG1 may include a first lens 610 and a second lens 620 arranged sequentially from the object side. The first lens 610 and the second lens 620 may be arranged at a predetermined interval. For example, the image-side surface of the first lens 610 may not contact the object-side surface of the second lens 620. However, the first lens 610 and the second lens 620 do not necessarily have to be arranged so that they do not contact each other. For example, the image-side surface of the first lens 610 may contact the object-side surface of the second lens 620.

[0294] The second lens group LG2 can include a plurality of lenses. For example, the second lens group LG2 can include a third lens 630 and a fourth lens 640 disposed in order from the object side. The third lens 630 and the fourth lens 640 can be disposed at a predetermined interval. For example, the image side surface of the third lens 630 can not be in contact with the object side surface of the fourth lens 640. However, the third lens 630 and the fourth lens 640 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the third lens 630 can be in contact with the object side surface of the fourth lens 640.

[0295] Next, characteristics of the first lens 610 to the fourth lens 640 included in the first lens group LG1 and the second lens group LG2 are described.

[0296] The first lens 610 can have a refractive power. For example, the first lens 610 can have a positive refractive power. The first lens 610 can have a convex object side surface and a convex image side surface. The first lens 610 can have a spherical surface. For example, both surfaces of the first lens 610 can be spherical. The second lens 620 can have a refractive power. For example, the second lens 620 can have a negative refractive power. The second lens 620 can have a convex object side surface and a concave image side surface. The second lens 620 can have an aspherical surface. For example, both surfaces of the second lens 620 can be aspherical. The third lens 630 can have a refractive power. For example, the third lens 630 can have a negative refractive power. The third lens 630 can have a concave object side surface and a concave image side surface. The third lens 630 can have a spherical surface. For example, both surfaces of the third lens 630 can be spherical. The fourth lens 640 can have a refractive power. For example, the fourth lens 640 can have a negative refractive power. The fourth lens 640 can have a convex object side surface and a concave image side surface. The fourth lens 640 can have an aspherical surface. For example, both surfaces of the fourth lens 640 can be aspherical.

[0297] Next, the first prism P1 and the second prism P2 as the optical path folding member are described. As a reference, the prisms described below are one type of the optical path folding member described in the claims, and can be changed to another member.

[0298] The first prism P1 and the second prism P2 can be disposed so that light incident through the first lens 610 to the fourth lens 640 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially disposed between the second lens 620 and the imaging plane IP along the optical path.

[0299] The first prism P1 can have a triangular cross-section. For example, a cross-section of the first prism P1 cut in a direction of an optical path can have a right triangle shape. An incident surface S5 of the first prism P1 and a projection surface S7 of the first prism P1 can form a substantially right angle. For example, the incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can be formed in portions other than a hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0300] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S6. The first reflection surface S6 can implement total reflection. For example, a first incident angle θ1 of the first reflection surface S6 can be greater than a critical angle of the first reflection surface S6. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S6. The first prism P1 configured as described above can reflect light incident from the second lens 620 to the second prism P2.

[0301] The second prism P2 can have a triangular cross-section. For example, a cross-section of the second prism P2 cut in a direction of an optical path can have a right triangle shape. The second prism P2 can include a plurality of reflection surfaces. For example, the second prism P2 can include a second reflection surface S13 and a third reflection surface S14.

[0302] The second prism P2 can implement total reflection and specular reflection. For example, the second reflection surface S13 of the second prism P2 can implement total reflection, and the third reflection surface S14 of the second prism P2 can implement specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflection surface S13 can be greater than a critical angle of the second reflection surface S13, and a third incident angle θ3 of the third reflection surface S14 can be less than a critical angle of the third reflection surface S14.

[0303] The second reflection surface S13 and the third reflection surface S14 can form an acute angle. For example, an angle θP2 between the second reflection surface S13 and the third reflection surface S14 can be 16 degrees to 32 degrees. The second reflection surface S13 and the third reflection surface S14 can have a predetermined angle with an incident surface S12 of the second prism P2. For example, an angle between the second reflection surface S13 and the incident surface S12 of the second prism P2 can be 58 degrees to 74 degrees, and an angle between the third reflection surface S14 and the incident surface S12 of the second prism P2 can be about 90 degrees.

[0304] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S12 of the second prism P2 can be reflected by the second reflection surface S13 and then reflected again by the third reflection surface S14.

[0305] One surface of the second prism P2 can achieve both reflection and projection. For example, the second reflecting surface S13 of the second prism P2 can transmit light incident from the third reflecting surface S14 while reflecting light incident through the incident surface S12 to the third reflecting surface S14.

[0306] The first reflecting surface S6, the second reflecting surface S13, and the third reflecting surface S14 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship therebetween. For example, the first incident angle θ1 can be smaller than the second incident angle θ2, and the third incident angle θ3 can be smaller than the first incident angle θ1.

[0307] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 600 by folding the optical path from the object side to the imaging plane IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 600 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 600 in the direction of the second optical axis C2.

[0308] The optical filter IF and the imaging plane IP can be disposed on one side of the second prism P2. For example, the optical filter IF and the imaging plane IP can be disposed to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the optical filter IF and the imaging plane IP can be disposed to face the second reflecting surface S13 of the second prism P2.

[0309] The optical filter IF can block light of a specific wavelength. For example, the optical filter IF according to the present exemplary embodiment can block infrared light. However, the type of light blocked by the optical filter IF is not limited to infrared light. For example, the optical filter IF can block ultraviolet light or visible light.

[0310] The imaging plane IP can be located at a point at which light reflected by the third reflecting surface S14 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging plane IP can be formed on or inside the image sensor IS.

[0311] The imaging lens system 600 configured as described above can exhibit Figure 15 aberration characteristics shown in Tables 11 and 12, respectively. Table 11 and Table 12 show the lens characteristics and aspherical values of the imaging lens system according to the present exemplary embodiment, respectively.

[0312] Table 11

[0313] Figure 16 Surface Number Component Radius of Curvature Thickness / Distance Refractive Index S1 Abbe Number 5.2750 0.900 1.537 55.7 S2 -35.6289 0.050 S3 First Lens 13.2037 0.500 1.669 20.3 S4 9.4598 0.800 S5 Second Lens First Prism 1.600 1.723 29.5 S6 Infinity 1.600 1.723 29.5 S7 Infinity 1.500 S8 Infinity -17.5264 0.882 1.669 20.3 S9 17.8445 0.080 S10 Third Lens 11.2450 1.505 1.537 55.7 S11 8.3425 0.800 S12 Fourth Lens Second Prism 3.500 1.723 29.5 S13 Infinity 2.000 1.723 29.5 S14 Infinity 1.000 1.723 29.5 S13 Infinity 0.200 S15 Infinity Filter 0.210 1.519 64.2 S16 Infinity 0.148 S17 Infinity Imaging Surface 0.000

[0314] Table 12

[0315]

[0316]

[0317] Next, referring to Infinity An imaging lens system according to a seventh exemplary embodiment is described.

[0318] The imaging lens system 700 according to the present exemplary embodiment can include a first lens group LG1, a first prism P1, a second lens group LG2, and a second prism P2. However, the components of the imaging lens system 700 are not limited to the above-described members. For example, the imaging lens system 700 can further include an optical filter IF and an imaging plane IP. The first lens group LG1, the first prism P1, the second lens group LG2, and the second prism P2 can be sequentially arranged from the object side. For example, the first lens group LG1 can be disposed on the object side of the first prism P1, and the second lens group LG2 can be disposed between the first prism P1 and the second prism P2.

[0319] Next, the above-described components are sequentially described.

[0320] The first lens group LG1 can include a plurality of lenses. For example, the first lens group LG1 can include a first lens 710 and a second lens 720 sequentially disposed from the object side. The first lens 710 and the second lens 720 can be disposed at a predetermined interval. For example, the image side surface of the first lens 710 can not be in contact with the object side surface of the second lens 720. However, the first lens 710 and the second lens 720 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the first lens 710 can be in contact with the object side surface of the second lens 720.

[0321] The second lens group LG2 can include a plurality of lenses. For example, the second lens group LG2 can include a third lens 730 and a fourth lens 740 sequentially disposed from the object side. The third lens 730 and the fourth lens 740 can be disposed at a predetermined interval. For example, the image side surface of the third lens 730 can not be in contact with the object side surface of the fourth lens 740. However, the third lens 730 and the fourth lens 740 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the third lens 730 can be in contact with the object side surface of the fourth lens 740.

[0322] Next, characteristics of the first lens 710 to the fourth lens 740 included in the first lens group LG1 and the second lens group LG2 are described.

[0323] The first lens 710 can have a refractive power. For example, the first lens 710 can have a positive refractive power. The first lens 710 can have a convex object side surface and a convex image side surface. The first lens 710 can have an aspherical surface. For example, both surfaces of the first lens 710 can be aspherical. The second lens 720 can have a refractive power. For example, the second lens 720 can have a negative refractive power. The second lens 720 can have a convex object side surface and a concave image side surface. The second lens 720 can have an aspherical surface. For example, both surfaces of the second lens 720 can be aspherical. The third lens 730 can have a refractive power. For example, the third lens 730 can have a negative refractive power. The third lens 730 can have a convex object side surface and a concave image side surface. The third lens 730 can have a spherical surface. For example, both surfaces of the third lens 730 can be spherical. The fourth lens 740 can have a refractive power. For example, the fourth lens 740 can have a negative refractive power. The fourth lens 740 can have a convex object side surface and a concave image side surface. The fourth lens 740 can have an aspherical surface. For example, both surfaces of the fourth lens 740 can be aspherical.

[0324] Next, the first prism P1 and the second prism P2 as the optical path folding members are described. As a reference, the prisms described below are one type of the optical path folding members described in the claims, and can be changed to another member.

[0325] The first prism P1 and the second prism P2 can be disposed so that light incident through the first lens 710 to the fourth lens 740 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially disposed between the second lens 720 and the imaging plane IP along the optical path.

[0326] The first prism P1 can have a triangular cross section. For example, a cross section of the first prism P1 cut in the direction of the optical path can have a right triangle shape. The incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can form a substantially right angle. For example, the incident surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can be formed in portions other than the hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0327] The first prism P1 can include a reflection surface. For example, the first prism P1 can include one first reflection surface S6. The first reflection surface S6 can achieve total reflection. For example, a first incident angle θ1 of the first reflection surface S6 can be greater than a critical angle of the first reflection surface S6. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, that is, the critical angle of the first reflection surface S6. The first prism P1 configured as described above can reflect light incident from the second lens 720 to the second prism P2.

[0328] The second prism P2 can have a triangular cross-section. For example, a cross-section of the second prism P2 cut in the optical path direction can have a right triangle shape. The second prism P2 can include a plurality of reflective surfaces. For example, the second prism P2 can include a second reflective surface S13 and a third reflective surface S14.

[0329] The second prism P2 can implement total reflection and specular reflection. For example, the second reflective surface S13 of the second prism P2 can implement total reflection, and the third reflective surface S14 of the second prism P2 can implement specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflective surface S13 can be greater than a critical angle of the second reflective surface S13, and a third incident angle θ3 of the third reflective surface S14 can be less than a critical angle of the third reflective surface S14.

[0330] The second reflective surface S13 and the third reflective surface S14 can form an acute angle. For example, an angle θP2 between the second reflective surface S13 and the third reflective surface S14 can be 16 degrees to 32 degrees. The second reflective surface S13 and the third reflective surface S14 can have a predetermined angle with the incident surface S12 of the second prism P2. For example, an angle between the second reflective surface S13 and the incident surface S12 of the second prism P2 can be 58 degrees to 74 degrees, and an angle between the third reflective surface S14 and the incident surface S12 of the second prism P2 can be about 90 degrees.

[0331] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S12 of the second prism P2 can be reflected by the second reflective surface S13 and then reflected again by the third reflective surface S14.

[0332] One surface of the second prism P2 can implement both reflection and projection. For example, the second reflective surface S13 of the second prism P2 can transmit light incident from the third reflective surface S14 while reflecting light incident through the incident surface S12 to the third reflective surface S14.

[0333] The first reflective surface S6, the second reflective surface S13, and the third reflective surface S14 of the first prism P1 and the second prism P2 can have a predetermined dimensional relationship. For example, the first incident angle θ1 can be less than the second incident angle θ2, and the third incident angle θ3 can be less than the first incident angle θ1.

[0334] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 700 by folding the optical path connecting from the object side to the imaging surface IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 700 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 700 in the direction of the second optical axis C2.

[0335] The optical filter IF and the imaging surface IP can be disposed on one side of the second prism P2. For example, the optical filter IF and the imaging surface IP can be disposed to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the optical filter IF and the imaging surface IP can be disposed to face the second reflecting surface S13 of the second prism P2.

[0336] The optical filter IF can block light of a specific wavelength. For example, the optical filter IF according to the present exemplary embodiment can block infrared light. However, the type of light blocked by the optical filter IF is not limited to infrared light. For example, the optical filter IF can block ultraviolet light or visible light.

[0337] The imaging surface IP can be located at a point at which light reflected by the third reflecting surface S14 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging surface IP can be formed on or inside the image sensor IS.

[0338] The imaging lens system 700 configured as described above can exhibit aberration characteristics as shown. Figure 17 Tables 13 and 14 show the lens characteristics and aspherical values of the imaging lens system according to the present exemplary embodiment, respectively.

[0339] Table 13

[0340]

[0341]

[0342] Table 14

[0343] Figure 18 S1 S2 S3 S4 S8 S9 S10 S11 k 3.12E-01 -9.90E+01 2.82E+01 -6.68E-01 -9.35E+01 3.72E+00 3.18E+01 -9.89E+00 A 2.00E-05 -6.28E-03 2.16E-02 1.24E-02 0 0 -3.75E-03 -3.70E-03 B 2.18E-04 1.53E-02 -1.01E-03 3.27E-04 0 0 -3.47E-04 -5.58E-04 C -1.14E-04 -1.48E-02 1.87E-04 1.51E-04 0 0 -1.09E-04 -2.32E-04 D 3.27E-05 7.97E-03 6.33E-04 -5.14E-05 0 0 -3.87E-05 -1.09E-04 E -7.09E-06 -2.60E-03 -2.31E-04 8.40E-04 0 0 -2.21E-05 -6.50E-05 F 5.71E-07 5.20E-04 -2.65E-04 -8.91E-04 0 0 -8.55E-06 -4.15E-05 G -4.16E-08 -6.19E-05 -2.90E-05 -2.81E-04 0 0 -1.61E-06 -2.84E-05 H 1.03E-09 4.04E-06 0 0 0 0 0 0 J 1.54E-09 -1.16E-07 0 0 0 0 0 0

[0344] Next, an imaging lens system according to an eighth exemplary embodiment is described with reference to Surface Number

[0345] ​The imaging lens system 800 according to the present exemplary embodiment can include a first lens group LG1, a first prism P1, a second lens group LG2, and a second prism P2. However, the components of the imaging lens system 800 are not limited to the above-described members. For example, the imaging lens system 800 can further include a filter IF and an imaging plane IP. The first lens group LG1, the first prism P1, the second lens group LG2, and the second prism P2 can be sequentially arranged from the object side. For example, the first lens group LG1 can be disposed on the object side of the first prism P1, and the second lens group LG2 can be disposed between the first prism P1 and the second prism P2.

[0346] Next, the above-described components are sequentially described.

[0347] The first lens group LG1 can include a plurality of lenses. For example, the first lens group LG1 can include a first lens 810 and a second lens 820 sequentially disposed from the object side. The first lens 810 and the second lens 820 can be disposed at a predetermined interval. For example, the image side surface of the first lens 810 can not be in contact with the object side surface of the second lens 820. However, the first lens 810 and the second lens 820 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the first lens 810 can be in contact with the object side surface of the second lens 820.

[0348] The second lens group LG2 can include a plurality of lenses. For example, the second lens group LG2 can include a third lens 830 and a fourth lens 840 sequentially disposed from the object side. The third lens 830 and the fourth lens 840 can be disposed at a predetermined interval. For example, the image side surface of the third lens 830 can not be in contact with the object side surface of the fourth lens 840. However, the third lens 830 and the fourth lens 840 can not necessarily be disposed not to be in contact with each other. For example, the image side surface of the third lens 830 can be in contact with the object side surface of the fourth lens 840.

[0349] Next, characteristics of the first lens 810 to the fourth lens 840 included in the first lens group LG1 and the second lens group LG2 are described.

[0350] The first lens 810 can have a refractive power. For example, the first lens 810 can have a positive refractive power. The first lens 810 can have a convex object side surface and a convex image side surface. The first lens 810 can have a spherical surface and an aspherical surface. For example, the object side surface of the first lens 810 can be spherical, and the image side surface of the first lens 810 can be aspherical. The second lens 820 can have a refractive power. For example, the second lens 820 can have a negative refractive power. The second lens 820 can have a convex object side surface and a concave image side surface. The second lens 820 can have an aspherical surface. For example, both surfaces of the second lens 820 can be aspherical. The third lens 830 can have a refractive power. For example, the third lens 830 can have a negative refractive power. The third lens 830 can have a convex object side surface and a concave image side surface. The third lens 830 can have an aspherical surface. For example, both surfaces of the third lens 830 can be aspherical. The fourth lens 840 can have a refractive power. For example, the fourth lens 840 can have a positive refractive power. The fourth lens 840 can have a convex object side surface and a concave image side surface. The fourth lens 840 can have an aspherical surface. For example, both surfaces of the fourth lens 840 can be aspherical.

[0351] Next, the first prism P1 and the second prism P2 as the optical path folding members are described. As a reference, the prisms described below are one type of the optical path folding members described in the claims, and can be changed to another type.

[0352] The first prism P1 and the second prism P2 can be disposed so that light incident through the first lens 810 to the fourth lens 840 is imaged on the imaging plane IP. For example, the first prism P1 and the second prism P2 can be sequentially disposed between the second lens 820 and the imaging plane IP along the optical path.

[0353] The first prism P1 can have a triangular cross section. For example, a cross section of the first prism P1 cut in the direction of the optical path can have a right triangle shape. The incidence surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can form a substantially right angle. For example, the incidence surface S5 of the first prism P1 and the projection surface S7 of the first prism P1 can be formed in portions other than the hypotenuse in the cross-sectional shape of the right triangle, respectively.

[0354] The first prism P1 can include a reflective surface. For example, the first prism P1 can include a first reflective surface S6. The first reflective surface S6 can implement total reflection. For example, a first incident angle θ1 of the first reflective surface S6 can be greater than a critical angle of the first reflective surface S6. In more detail, the first incident angle θ1 can be 45 degrees, which is greater than 41.2 degrees, i.e., the critical angle of the first reflective surface S6. The first prism P1 configured as described above can reflect light incident from the second lens 820 to the second prism P2.

[0355] The second prism P2 can have a triangular cross-section. For example, a cross-section of the second prism P2 cut in the optical path direction can have a right triangle shape. The second prism P2 can include a plurality of reflective surfaces. For example, the second prism P2 can include a second reflective surface S13 and a third reflective surface S14.

[0356] The second prism P2 can implement total reflection and specular reflection. For example, the second reflective surface S13 of the second prism P2 can implement total reflection, and the third reflective surface S14 of the second prism P2 can implement specular reflection or mirror reflection. As a specific example, a second incident angle θ2 of the second reflective surface S13 can be greater than a critical angle of the second reflective surface S13, and a third incident angle θ3 of the third reflective surface S14 can be less than a critical angle of the third reflective surface S14.

[0357] The second reflective surface S13 and the third reflective surface S14 can form an acute angle. For example, an angle θP2 between the second reflective surface S13 and the third reflective surface S14 can be 16 to 32 degrees. The second reflective surface S13 and the third reflective surface S14 can have a predetermined angle with the incident surface S12 of the second prism P2. For example, an angle between the second reflective surface S13 and the incident surface S12 of the second prism P2 can be 58 to 74 degrees, and an angle between the third reflective surface S14 and the incident surface S12 of the second prism P2 can be about 90 degrees.

[0358] The second prism P2 can implement multiple internal reflections. For example, light incident through the incident surface S12 of the second prism P2 can be reflected by the second reflective surface S13 and then reflected again by the third reflective surface S14.

[0359] One surface of the second prism P2 can implement both reflection and projection. For example, the second reflective surface S13 of the second prism P2 can transmit light incident from the third reflective surface S14 while reflecting light incident through the incident surface S12 to the third reflective surface S14.

[0360] A predetermined dimensional relationship can be present among the first reflecting surface S6, the second reflecting surface S13, and the third reflecting surface S14 of the first prism P1 and the second prism P2. For example, the first incidence angle θ1 can be smaller than the second incidence angle θ2, and the third incidence angle θ3 can be smaller than the first incidence angle θ1.

[0361] The first prism P1 and the second prism P2 configured as described above can miniaturize and integrate the imaging lens system 800 by folding the optical path from the object side to the imaging surface IP. For example, the first prism P1 can fold the optical path extending along the first optical axis C1 in the direction of the second optical axis C2 intersecting the first optical axis C1, thereby reducing the length of the imaging lens system 800 in the direction of the first optical axis C1. In another example, the second prism P2 can fold the optical path extending along the second optical axis C2 twice or more by total reflection and mirror reflection, thereby reducing the length of the imaging lens system 800 in the direction of the second optical axis C2.

[0362] The optical filter IF and the imaging surface IP can be disposed on one side of the second prism P2. For example, the optical filter IF and the imaging surface IP can be disposed to face the hypotenuse having the largest length in the cross-sectional shape of the second prism P2. As a specific example, the optical filter IF and the imaging surface IP can be disposed to face the second reflecting surface S13 of the second prism P2.

[0363] The optical filter IF can block light of a specific wavelength. For example, the optical filter IF according to the present exemplary embodiment can block infrared light. However, the type of light blocked by the optical filter IF is not limited to infrared light. For example, the optical filter IF can block ultraviolet light or visible light.

[0364] The imaging surface IP can be located at a point at which light reflected by the third reflecting surface S14 converges or an image is formed, and can be formed by an image sensor IS or the like. For example, the imaging surface IP can be formed on or inside the image sensor IS.

[0365] The imaging lens system 800 configured as described above can exhibit aberration characteristics as shown. Figure 19 Table 15 and Table 16 show the lens characteristics and aspherical values of the imaging lens system according to the present exemplary embodiment, respectively.

[0366] Table 15

[0367]

[0368]

[0369] Table 16

[0370] Figure 20 S1 S2 S3 S4 S8 S9 S10 S11 k 3.21E-01 -9.90E+01 2.80E+01 9.60E-02 9.35E+01 -3.30E+00 -3.16E+01 4.27E+01 A 0 -6.00E-03 -6.00E-03 2.00E-03 -1.00E-03 0 6.00E-03 2.00E-02 B 0 1.50E-02 -2.00E-03 -2.30E-02 0 0 -6.90E-02 -1.09E-01 C 0 -1.50E-02 1.20E-02 4.60E-02 0 0 1.76E-01 2.79E-01 D 0 8.00E-03 -1.70E-02 -5.20E-02 0 0 -2.97E-01 -4.49E-01 E 0 -3.00E-03 1.20E-02 3.60E-02 0 0 3.24E-01 4.58E-01 F 0 1.00E-03 -5.00E-03 -1.50E-02 0 0 -2.24E-01 -2.96E-01 G 0 0 1.00E-03 4.00E-03 0 0 9.40E-02 1.17E-01 H 0 0 0 -1.00E-03 -6.81E-07 -1.04E-06 -2.20E-02 -2.57E-02 J 0 0 0 0 -2.49E-07 -4.07E-07 2.16E-03 2.39E-03

[0371] Tables 17 and 18 show optical characteristic values and conditional expression values of the imaging lens systems according to the first to eighth exemplary embodiments described above, respectively.

[0372] Table 17

[0373]

[0374]

[0375] Table 18

[0376]

[0377] Next, an electronic device according to the present disclosure is described.

[0378] An electronic device according to the present disclosure can include an imaging lens system according to an exemplary embodiment. For example, the electronic device can include one or more of the imaging lens systems according to the first to eighth exemplary embodiments. As a specific example, the electronic device can include the imaging lens system 100 according to the first exemplary embodiment. In another example, the electronic device can include the imaging lens system 100 according to the first exemplary embodiment and the imaging lens system 800 according to the eighth exemplary embodiment. In another example, the electronic device can include two imaging lens systems 200 according to the second exemplary embodiment and the imaging lens system 600 according to the sixth exemplary embodiment. However, the imaging lens system that can be located in the electronic device according to the exemplary embodiments is not limited to the above-described types.

[0379] Next, an electronic device according to an exemplary embodiment is described with reference to Surface Number and Figure 21 Next, an electronic device according to an exemplary embodiment is described with reference to

[0380] The electronic device 1000 according to an exemplary embodiment can be a portable terminal. For example, the electronic device 1000 can be a smartphone. However, the type of the electronic device 1000 is not limited to a smartphone. For example, the electronic device according to another exemplary embodiment can be a laptop computer.

[0381] The electronic device 1000 can include one or more camera modules 10 and 20. For example, two camera modules 10 and 20 can be mounted in the electronic device 1000. The first camera module 10 and the second camera module 20 can be disposed to image an object in the same direction. For example, the first camera module 10 and the second camera module 20 can be mounted on one surface of the electronic device 1000 so as to be parallel to each other.

[0382] At least one of the first camera module 10 and the second camera module 20 can include an imaging lens system according to the first to eighth exemplary embodiments. For example, the first camera module 10 can include the imaging lens system 100 according to the first exemplary embodiment.

[0383] The first camera module 10 can implement high resolution. In detail, as shown, the first camera module 10 can have an image sensor IS diagonally disposed with respect to a thickness direction of the electronic device 1000, and thus have a large image sensor IS required to implement high resolution. In more detail, the image sensor IS can be disposed at an inclination of 18 to 30 degrees with respect to a front of the electronic device 1000 or a display device (e.g., a display panel). Figure 22 Figure 22

[0384] The electronic device 1000 configured as described above can mount an image sensor and a camera module including the same, which are larger than an internal space (particularly, a thickness thereof), and thus can simultaneously improve performance of the camera module and reduce a thickness of the electronic device.

[0385] As described above, the present disclosure can provide an imaging lens system that can be mounted in a small terminal or a thin terminal.

[0386] Further, the present disclosure can provide a camera module having a telephoto imaging lens system.

[0387] While specific exemplary embodiments have been shown and described above, it will be apparent that various modifications in form and detail can be made 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 within each example should be considered as being applicable to similar features or aspects within other examples. Proper results can be achieved if the described techniques are performed in a different order, and / or if components in the described systems, architectures, devices, or circuits are combined in a different manner, and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of the present disclosure is defined not by the specific exemplary embodiments, but by the following 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 present disclosure.​

Claims

1. An imaging lens system, comprising: An optical path folding component includes a foremost reflecting surface, a last reflecting surface, and a rear reflecting surface, wherein the foremost reflecting surface is disposed closest to the object side, the last reflecting surface is disposed closest to the imaging surface, and the rear reflecting surface is configured to form an acute angle with the last reflecting surface and to reflect light reflected by the last reflecting surface to the imaging surface; and The first lens group is disposed on the object side of the foremost reflecting surface or on the image side of the foremost reflecting surface. The angle between the first virtual plane including the foremost reflective surface and the second virtual plane including the last reflective surface is between 15 degrees and 27 degrees. Wherein, the imaging surface is configured to face the final reflecting surface, and The first lens group includes at least one lens having an aspherical surface.

2. The imaging lens system according to claim 1, wherein, The first lens group includes a first lens and a second lens arranged sequentially from the object side.

3. The imaging lens system according to claim 2, wherein, The first lens has positive refractive power, and the second lens has negative refractive power.

4. The imaging lens system according to claim 2, wherein, 30 < V1-V2, where V1 is the Abbe number of the first lens and V2 is the Abbe number of the second lens.

5. The imaging lens system according to claim 1, wherein, The angle between the final reflective surface and the rear reflective surface is 18 to 30 degrees.

6. The imaging lens system according to claim 1, wherein, The optical path folding component also includes: The first optical path folding component includes the foremost reflective surface; and The second optical path folding component includes the rear reflective surface and the final reflective surface.

7. The imaging lens system according to claim 6 further includes a second lens group, the second lens group being disposed on the object side or the image side of the foremost reflecting surface where the first lens group is not disposed.

8. The imaging lens system according to claim 7, wherein, The second lens group includes one or more lenses.

9. The imaging lens system according to claim 1, wherein, BFL / TTL < 0.9, where BFL is the distance from the image-side surface of the last lens of the first lens group to the imaging plane, and TTL is the distance from the object-side surface of the foremost lens of the first lens group to the imaging plane.

10. Camera module, including: The imaging lens system according to any one of claims 1 to 9; as well as Image sensor, The imaging surface is disposed on the image sensor.

11. An electronic device, comprising the camera module of claim 10, wherein, The image sensor is positioned diagonally relative to the thickness direction of the electronic device.

12. An imaging lens system, comprising: The first optical path folding component has a first reflective surface and a right-angled triangular cross-sectional shape; The second optical path folding member has two or more reflective surfaces, including a second reflective surface and a third reflective surface, and has a right-angled triangular cross-sectional shape; The lens unit is configured to face the incident surface or the exit surface of the first optical path folding member; as well as The imaging plane is located on the image side of the second optical path folding member. The first reflective surface, the second reflective surface, the third reflective surface, and the imaging surface are arranged sequentially along the optical axis of the lens unit. Wherein, the imaging surface is configured to face the second reflective surface, and The lens unit includes at least one lens having an aspherical surface.

13. The imaging lens system according to claim 12, wherein, The second reflective surface reflects light emitted from the first optical path folding member; and The third reflective surface reflects the light reflected from the second reflective surface back to the second reflective surface.

14. The imaging lens system according to claim 13, wherein, The angle between the second reflective surface and the third reflective surface is 16 degrees to 32 degrees.

15. The imaging lens system according to claim 12, wherein, The maximum length of the incident surface of the first optical path folding member is less than the maximum length of the exit surface of the second optical path folding member.

16. The imaging lens system according to claim 12, wherein, The distance from the exit surface of the first optical path folding member to the incident surface of the second optical path folding member is greater than the distance from the exit surface of the second optical path folding member to the imaging surface.

17. The imaging lens system according to claim 12, wherein, The lens unit includes a first lens group disposed on the object side of the first optical path folding member.

18. The imaging lens system according to claim 12, wherein, The lens unit includes a first lens group disposed between the first optical path folding member and the second optical path folding member.

19. The imaging lens system according to claim 12, wherein, The lens unit includes: The first lens group is disposed on the object side of the first optical path folding member; and The second lens group is disposed between the first optical path folding member and the second optical path folding member.

20. A camera module comprising an imaging lens system according to any one of claims 12 to 19.

21. An electronic device, comprising the camera module of claim 20, in, The imaging surface is set on the image sensor, and The image sensor is positioned diagonally relative to the thickness direction of the electronic device.

22. An imaging lens system, comprising: The optical path folding member includes a first reflective surface, a second reflective surface, and a third reflective surface configured to sequentially reflect light incident from the object side; The first lens group is disposed on the object side or image side of the first reflecting surface; as well as An imaging surface is configured to face the second reflective surface, wherein a first incident angle of the first reflective surface is smaller than a second incident angle of the second reflective surface, and a third incident angle of the third reflective surface is smaller than the first incident angle of the first reflective surface. The first lens group includes at least one lens having an aspherical surface.

23. The imaging lens system according to claim 22, wherein, The first incident angle and the second incident angle are greater than the critical angle of the first reflecting surface and the critical angle of the second reflecting surface, respectively, and the third incident angle is less than the critical angle of the third reflecting surface.

24. The imaging lens system according to claim 22, wherein, The first incident angle and the second incident angle are greater than 36 degrees and less than 90 degrees, respectively.

25. The imaging lens system according to claim 22, wherein, The third incident angle is greater than 28 degrees and less than 56 degrees.

26. Electronic devices, including: A camera module comprising: an imaging lens system according to any one of claims 22 to 25; and an image sensor including an imaging surface configured to face the second reflective surface. The image sensor is positioned diagonally relative to the thickness direction of the electronic device.

27. An imaging lens system, comprising: The first lens has positive refractive power; The second lens has negative refractive power, a convex object side, and a concave image side; The third lens has refractive power and a concave image side; A first reflective surface, a second reflective surface, and a third reflective surface are sequentially arranged along the optical axis from the object side; as well as The imaging surface is configured to face the second reflective surface. The first lens, the second lens, the third lens, the second reflective surface, and the third reflective surface are sequentially arranged along the optical axis from the object side. At least one of the first lens to the third lens has an aspherical surface.

28. The imaging lens system according to claim 27, wherein, The angle between the first virtual plane including the first reflective surface and the second virtual plane including the second reflective surface is 15 degrees to 27 degrees.

29. The imaging lens system according to claim 27, wherein, The imaging surface is arranged along the optical axis and parallel to the virtual plane including the second reflective surface.

30. The imaging lens system according to claim 27, wherein, The first incident angle of the first reflective surface is less than the second incident angle of the second reflective surface, and the third incident angle of the third reflective surface is less than the first incident angle of the first reflective surface.

31. The imaging lens system of claim 27 further includes a fourth lens having refractive power and disposed along the optical axis between the first reflective surface and the second reflective surface.

32. The imaging lens system of claim 27 further includes a fourth reflective surface and a fifth reflective surface, the fourth reflective surface and the fifth reflective surface being disposed between the first reflective surface and the second reflective surface along the optical axis.

33. The imaging lens system according to claim 27, wherein, The optical axis extends multiple times between the second reflective surface and the third reflective surface.

34. The imaging lens system according to claim 27, wherein, The third lens is disposed between the first reflective surface and the second reflective surface along the optical axis.

35. Electronic devices, including: The camera module includes the imaging lens system according to any one of claims 27 to 34; And an image sensor, including an imaging surface configured to face the second reflective surface. The image sensor is positioned diagonally relative to the thickness direction of the electronic device.

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