Imaging lens system

Abstract

An imaging lens system according to an embodiment of the present disclosure includes: a first lens group including one or more lenses; and a second lens group including one or more lenses and configured to be movable in the optical axis direction. In an imaging lens system according to an embodiment of the present disclosure, a first lens group and a second lens group are arranged in order from an object side. An imaging lens system according to an embodiment of the present disclosure satisfies a conditional expression 2.80 < = fG1R / f < = 4.0, where f is a focal length of the imaging lens system, and fG1R is a focal length of a first rear lens disposed closest to an imaging plane in the first lens group.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority from Korean Patent Application No. 10-2023-0175849 filed in the Korean Intellectual Property Office on December 6, 2023, the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] The following description relates to an imaging lens system configured to achieve thinning and minimize resolution deterioration due to focus adjustment. Background Art

[0004] A portable electronic device may include a camera module for capturing still images or recording moving images. For example, the camera module may be mounted on a mobile phone, a laptop, a game console, etc. Such portable electronic devices are usually manufactured to be compact or small in size to improve the convenience of the user carrying the device. Therefore, the camera module mounted on the portable electronic device is configured to have an imaging lens system of limited form. For example, because the distance from the front lens to the imaging surface is quite large, it is difficult to mount an imaging lens system including multiple lenses on a portable electronic device. A portable electronic device with a high-performance camera module may require an imaging lens system with a small resolution change caused by the movement of the focusing lens or focusing lens group.

[0005] The above information is presented as background information only to assist with understanding the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with respect to the present disclosure. Summary of the invention

[0006] The purpose of providing this summary is to introduce a selection of concepts in a concise form, and these concepts will be further described in the following detailed description. This summary is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to help determine the scope of the claimed subject matter.

[0007] In a general aspect, an imaging lens system includes: a first lens group including one or more lenses; and a second lens group including one or more lenses and configured to be movable in an optical axis direction. The first lens group and the second lens group are arranged in sequence from the object side. The imaging lens system satisfies 2.80≤fG1R / f≤4.0, where f is the focal length of the imaging lens system, and fG1R is the focal length of the first rear lens disposed closest to the imaging plane in the first lens group.

[0008] The first rear lens may have a convex image-side surface.

[0009] The first lens group may have a total of two lenses.

[0010] The second lens group may have a total of four, five, or six lenses.

[0011] The last lens disposed closest to the imaging surface may have a positive refractive power.

[0012] The frontmost lens disposed closest to the object may have a negative refractive power.

[0013] The imaging lens system may satisfy -1.50 < fF / f < -1.20, where fF is the focal length of the frontmost lens disposed closest to the object.

[0014] In another general aspect, the imaging lens system includes a first lens, an optical path converter, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side. The imaging lens system satisfies 2.80 ≤ f2 / f ≤ 4.0 and 1.40 < D12 / f < 2.20, where f is the focal length of the imaging lens system, f2 is the focal length of the second lens, and D12 is the distance from the image side surface of the first lens to the object side surface of the second lens.

[0015] The first lens may have a convex object side surface.

[0016] The second lens may have a convex object side surface.

[0017] The third lens may have a convex object side surface.

[0018] The fourth lens may have a convex object side surface.

[0019] The fifth lens may have a concave object side surface.

[0020] The sixth lens may have a convex object side surface.

[0021] The imaging lens system may further include a seventh lens disposed on the image side of the sixth lens.

[0022] The seventh lens may have a convex object side surface.

[0023] In another general aspect, the imaging lens system includes: a first lens group including one or more lenses; and a second lens group including one or more lenses and configured to be movable in the optical axis direction. The first lens group and the second lens group are arranged in sequence from the object side. The imaging lens system satisfies -1.5 < f1 / f < -1.20 and 2.80 ≤ f2 / f ≤ 4.0, where f is the focal length of the imaging lens system, f1 is the focal length of the first lens of the imaging lens system, and f2 is the focal length of the second lens of the imaging lens system.

[0024] The first rear lens disposed closest to the imaging plane in the first lens group may have a convex image-side surface.

[0025] The first lens group may have a total of two lenses.

[0026] The second lens group may have a total of four, five, or six lenses, and a last lens disposed closest to the imaging plane in the second lens group may have positive refractive power.

[0027] Other features and aspects will be apparent from the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a configuration diagram of an imaging lens system according to an embodiment of the present disclosure.

[0029] Figure 2 yes Figure 1 Aberration curves of the imaging lens system shown in .

[0030] Figure 3 is a configuration diagram of an imaging lens system according to an embodiment of the present disclosure.

[0031] Figure 4 yes Figure 3 Aberration curves of the imaging lens system shown in .

[0032] Figure 5 is a configuration diagram of an imaging lens system according to an embodiment of the present disclosure.

[0033] Figure 6 yes Figure 5 Aberration curves of the imaging lens system shown in .

[0034] Figure 7 is a configuration diagram of an imaging lens system according to an embodiment of the present disclosure.

[0035] Figure 8 yes Figure 7 Aberration curves of the imaging lens system shown in .

[0036] Fig. 9 is an enlarged view of a first lens and an optical path converter according to an embodiment of the present disclosure.

[0037] Fig.10 An electronic device including an imaging lens system according to an embodiment of the present disclosure.

[0038] Throughout the drawings and detailed description, unless otherwise described, the same reference numerals refer to the same elements. For purposes of clarity, illustration, and convenience, the drawings may not be drawn to scale, and the relative sizes, proportions, and depictions of elements in the drawings may be exaggerated. DETAILED DESCRIPTION

[0039] Hereinafter, although examples of the present disclosure will be described in detail with reference to the accompanying drawings, it should be noted that the examples are not limited thereto.

[0040] The following specific embodiments are provided to help the reader gain a comprehensive understanding of the methods, devices and / or systems described herein. However, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be apparent after understanding the present disclosure. For example, the order of operations described herein is merely an example, and except for operations that must occur in a particular order, it is not limited to the order set forth herein, but can be changed, which will be apparent after understanding the present disclosure. In addition, for greater clarity and brevity, descriptions of features known in the art may be omitted.

[0041] The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein are provided merely to illustrate some of the many possible ways to implement the methods, devices, and / or systems described herein that will be apparent after understanding the present disclosure.

[0042] Throughout the specification, when an element such as a layer, a region, or a substrate is described as being “on,” “connected to,” or “coupled to” another element, the element may be directly “on,” “connected to,” or “coupled to” the other element, or one or more other elements may be present between the element and the other element. Conversely, when an element is described as being “directly on,” “directly connected to,” or “directly coupled to” another element, no other elements may be present between the element and the other element.

[0043] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more items; similarly, "at least one" includes any one of the associated listed items and any combination of any two or more items.

[0044] Although terms such as "first", "second" and "third" may be used herein to describe various members, components, regions, layers or portions, these members, components, regions, layers or portions are not limited by these terms. Rather, these terms are only used to distinguish one member, component, region, layer or portion from another member, component, region, layer or portion. Therefore, without departing from the teachings of the examples described herein, the first member, first component, first region, first layer or first portion mentioned in these examples may also be referred to as the second member, second component, second region, second layer or second portion.

[0045] Spatially relative terms such as "above", "above", "below", "below", etc. may be used herein for descriptive convenience to describe the relationship of one element relative to another element as shown in the accompanying drawings. In addition to covering the orientations depicted in the accompanying drawings, these spatially relative terms are intended to also cover different orientations of the device in use or operation. For example, if the device in the accompanying drawings is flipped, an element described as being "above" or "above" another element relative to the other element will be "below" or "below" the other element relative to the other element. Therefore, depending on the spatial orientation of the device, the term "above" covers both orientations of "above" and "below". The device may also be oriented in other ways (e.g., rotated 90 degrees or in other orientations), and the spatially relative terms used herein should be interpreted accordingly.

[0046] The terms used herein are only used to describe various examples and are not intended to limit the present disclosure. Unless the context clearly indicates otherwise, the terms "a", "an" and "the" are intended to include plural forms as well. The terms "include", "comprise" and "have" indicate the presence of the features, quantities, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements and / or combinations thereof.

[0047] Variations in the shapes shown in the drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings but include variations in shapes that occur during manufacturing.

[0048] It should be noted that herein, use of the word “may” with respect to an example, such as regarding what an example may include or implement, means that there is at least one example in which such feature is included or implemented, and all examples are not limited thereto.

[0049] The features of the examples described herein may be combined in various ways that will be apparent after understanding the present disclosure. In addition, although the examples described herein have various configurations, other configurations that will be apparent after understanding the present disclosure are also possible.

[0050] In this specification, the front lens or the first lens refers to the lens closest to the object (or subject), and the last lens refers to the lens closest to the imaging plane (or image sensor). In this specification, the units of the radius of curvature, thickness, TTL (the distance from the object side of the first lens to the imaging plane), IMG HT (or Y: the height of the imaging plane), and focal length are expressed in millimeters (mm).

[0051] The thickness of the lens, the gap between lenses, and TTL refer to the distance measured on the optical axis. In addition, in the description of the shape of the lens, the configuration that one surface is convex means that the paraxial region of the surface can be convex, and the configuration that one surface is concave means that the paraxial region of the surface can be concave. Therefore, even when one surface of the lens is described as convex, the edge of the lens can be concave. Similarly, even when one surface of the lens is described as concave, the edge of the lens can be convex.

[0052] An imaging lens system according to an embodiment of the present disclosure may include two lens groups. For example, an imaging lens system according to an embodiment of the present disclosure may include a first lens group and a second lens group arranged in sequence from the object side. An imaging lens system according to an embodiment of the present disclosure may include a lens group movable in the optical axis direction. For example, in an imaging lens system according to an embodiment of the present disclosure, the second lens group may be configured to be movable in the optical axis direction. An imaging lens system according to an embodiment of the present disclosure may satisfy a specific conditional expression. For example, an imaging lens system according to an embodiment of the present disclosure may satisfy the conditional expression 2.80≤fG1R / f≤4.0. In the conditional expression, fG1R is the focal length of the first rear lens disposed closest to the imaging surface in the first lens group, and f is the focal length of the imaging lens system.

[0053] The imaging lens system according to the embodiment of the present disclosure may include one or more of the features listed below as needed.

[0054] For example, the imaging lens system according to the embodiment of the present disclosure may include a lens having a convex image-side surface.For example, in the imaging lens system according to the embodiment of the present disclosure, the first rear lens may have a convex image-side surface.

[0055] As another example, in an imaging lens system according to an embodiment of the present disclosure, the first lens group and the second lens group may include two or more lenses, respectively. For example, the first lens group may have two lenses, and the second lens group may have four, five, or six lenses. However, the number of lenses constituting the first lens group and the second lens group is not limited to the above form.

[0056] As another example, the imaging lens system according to the embodiment of the present disclosure may include a lens having positive refractive power. For example, in the imaging lens system according to the embodiment of the present disclosure, the last lens disposed closest to the imaging plane may have positive refractive power.

[0057] As another example, the imaging lens system according to the embodiment of the present disclosure may include a lens having negative refractive power. For example, in the imaging lens system according to the embodiment of the present disclosure, the frontmost lens disposed closest to the object may have negative refractive power.

[0058] As another example, the imaging lens system according to the embodiment of the present disclosure may also satisfy a specific conditional expression. For example, the imaging lens system according to the embodiment of the present disclosure may satisfy the conditional expression -1.50≤fF / f≤-1.20. In the conditional expression, fF is the focal length of the front lens.

[0059] As another example, the imaging lens system according to the embodiment of the present disclosure may include an optical path converter. For example, in the imaging lens system according to the embodiment of the present disclosure, the first lens group may include an optical path converter disposed on the image side of the lens.

[0060] An imaging lens system according to an embodiment of the present disclosure may include two lens groups. For example, an imaging lens system according to an embodiment of the present disclosure may include a first lens group and a second lens group arranged in sequence from the object side. An imaging lens system according to an embodiment of the present disclosure may include a lens group movable in the optical axis direction. For example, in an imaging lens system according to an embodiment of the present disclosure, the second lens group may be configured to be movable in the optical axis direction. Therefore, an imaging lens system according to an embodiment of the present disclosure may adjust the focus by driving the second lens group.

[0061] An imaging lens system according to an embodiment of the present disclosure may have specific optical properties. For example, an imaging lens system according to an embodiment of the present disclosure may have an f-number of 2.0 or less and a half field of view (HFOV) of 30 degrees or more. However, in an imaging lens system having the above-mentioned field of view and f-number, aberrations may increase rapidly. An embodiment of the present disclosure may include a lens with negative refractive power, so that aberrations can be reduced. For example, in an imaging lens system according to an embodiment of the present disclosure, the frontmost lens disposed closest to the object may have a negative refractive power.

[0062] The imaging lens system according to an embodiment of the present disclosure may be configured to enable miniaturization of the camera module. For example, the imaging lens system according to an embodiment of the present disclosure may include an optical path converter. As a specific example, in the imaging lens system according to an embodiment of the present disclosure, the optical path converter may be included in the first lens group. However, if multiple lenses are arranged on the object side of the optical path converter, the problem of increasing the size of the optical path converter may arise. Therefore, it may be desirable to arrange a lens on the object side of the optical path converter. The optical path converter may be in the form of a prism or a reflector.

[0063] If necessary, the imaging lens system according to an embodiment of the present disclosure may include a lens having a convex object side surface. For example, in the imaging lens system according to an embodiment of the present disclosure, the frontmost lens disposed on the object side of the optical path converter may have a convex object side surface. The frontmost lens of the above shape may be conducive to thinning the imaging lens system.

[0064] The imaging lens system according to the embodiment of the present disclosure may include a lens with positive refractive power as needed. For example, in the imaging lens system according to the embodiment of the present disclosure, the first rear lens disposed on the image side closest to the optical path converter may have positive refractive power. The first rear lens may perform the function of reducing the total aperture (effective aperture) of the second lens group. In addition, when correcting hand shake of the camera module, the first rear lens with positive refractive power may be beneficial in reducing the amount of movement of the first lens group.

[0065] According to an embodiment of the present disclosure, the imaging lens system may include a lens having an inflection point as required. For example, in the imaging lens system according to an embodiment of the present disclosure, the last lens closest to the imaging surface may have an inflection point formed on at least one of the object side surface and the image side surface. Such a shape of the last lens may be conducive to satisfying the CRA (chief ray angle) of the light formed on the imaging surface.

[0066] In an imaging lens system according to an embodiment of the present disclosure, the number of lenses constituting the second lens group may be greater than the number of lenses constituting the first lens group. For example, in an imaging lens system according to an embodiment of the present disclosure, the first lens group may have two lenses (excluding the optical path converter), and the second lens group may have four or five lenses. The second lens group satisfying the above relationship may be advantageous for correcting the aberration caused by the first lens group.

[0067] An imaging lens system according to an embodiment of the present disclosure may include a plurality of lenses. For example, an imaging lens system according to an embodiment of the present disclosure may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side. However, the number of lenses constituting the imaging lens system according to an embodiment of the present disclosure is not limited to six. For example, an imaging lens system according to an embodiment of the present disclosure may further include a seventh lens disposed on the image side of the sixth lens. As another example, an imaging lens system according to an embodiment of the present disclosure may further include a seventh lens and an eighth lens sequentially disposed on the image side of the sixth lens. An imaging lens system according to an embodiment of the present disclosure satisfies a specific conditional expression. For example, an imaging lens system according to an embodiment of the present disclosure may satisfy the conditional expressions 2.80 ≤ f2 / f ≤ 4.0 and 1.40 < D12 / f < 2.20. In the conditional expressions, f2 is the focal length of the second lens, and D12 is the distance from the image side surface of the first lens to the object side surface of the second lens.

[0068] An imaging lens system according to an embodiment of the present disclosure may include a plurality of lens groups. For example, according to an embodiment of the present disclosure, an imaging lens system may include a first lens group and a second lens group arranged in sequence from the object side. An imaging lens system according to an embodiment of the present disclosure may satisfy one or more of the following conditional expressions:

[0069] 1) f-number ≤ 2.0

[0070] 2) 30° ≤ HFOV

[0071] 3) -1.50 ≤ fF / f ≤ -1.20

[0072] 4) 0.20 ≤ T1 / SL1 ≤ 0.40

[0073] 5) 0.70 ≤ Dp / 2Y ≤ 1.20

[0074] 6) 1.20 ≤ LG2R1 / f ≤ 1.50

[0075] 7) 0.60 ≤ L1ST / STY ≤ 1.80

[0076] 8) |f / fR| ≤ 0.15

[0077] 9) 0.90≤EDLF / EDLR≤1.20

[0078] 10)2.80≤fG1R / f≤4.0

[0079] In the above conditional expressions, f is the focal length of the imaging lens system, fF is the focal length of the front lens disposed closest to the object, T1 is the thickness of the front lens at the center of the optical axis, and SL1 is the sag value of the image side surface of the front lens (see Fig. 9 ), Dp is the length of the reflecting surface of the optical path converter, 2Y is the diagonal length of the imaging plane, LG2R1 is the radius of curvature of the object side surface of the second front lens disposed closest to the object in the second lens group, L1ST is the distance from the object side surface of the front lens to the aperture, STY is the distance from the aperture to the imaging plane, fR is the focal length of the last lens disposed closest to the imaging plane, EDLF is the effective diameter of the front lens, EDLR is the effective diameter of the last lens, and fG1R is the focal length of the lens disposed closest to the imaging plane in the first lens group (or the lens closest to the image side of the optical path converter).

[0080] Conditional Expression 3 may provide a numerical range for limiting the refractive power of the frontmost lens. For example, for the frontmost lens exceeding the lower limit value of Conditional Expression 3, it is difficult to realize an imaging lens system with a wide angle of view. As another example, the frontmost lens exceeding the upper limit value of Conditional Expression 3 may be advantageous for realizing an imaging lens system with a wide angle of view, but because aberration correction is difficult, it may be difficult to realize a high-resolution imaging lens system.

[0081] Conditional Expression 4 may provide a numerical range that limits the shape of the frontmost lens. For example, the frontmost lens exceeding the lower limit value of Conditional Expression 4 may be difficult to manufacture due to its thin thickness, or the sag value of the image side surface of the frontmost lens may be excessively increased. As another example, the frontmost lens exceeding the upper limit value of Conditional Expression 4 may be easily manufactured, but it may be difficult to realize an imaging lens system with a wide angle of view.

[0082] Conditional Expression 5 may provide a numerical range for limiting the performance and size of the imaging lens system. For example, an optical path converter exceeding the lower limit value of Conditional Expression 5 may cause unnecessary vignetting and make it difficult to realize a bright optical system. As another example, an optical path converter exceeding the upper limit value of Conditional Expression 5 increases the overall size of the imaging lens system, making it difficult to apply to a small camera module.

[0083] Conditional Expression 6 can provide a numerical range for limiting the aberration characteristics and size of the imaging lens system. For example, a second front lens exceeding the lower limit value of Conditional Expression 6 may increase the aberration of the imaging lens system. As another example, a second front lens exceeding the upper limit value of Conditional Expression 6 may weaken the refractive power of the second lens group, making it difficult to adjust the focus by the second lens group. In addition, a second front lens exceeding the upper limit value of Conditional Expression 6 increases the amount of movement of the second lens group for focus adjustment, making it difficult to miniaturize the imaging lens system.

[0084] Conditional Expression 7 may provide a numerical range for limiting the position of the aperture. For example, an aperture exceeding the lower limit value of Conditional Expression 7 may be set too close to the object, which may cause a problem of increasing the size (e.g., effective diameter) of the last lens. As another example, an aperture exceeding the upper limit value of Conditional Expression 7 may have a problem of increasing the size (e.g., effective diameter) of the frontmost lens. In detail, an aperture exceeding the numerical range of Conditional Expression 7 may make it difficult to miniaturize the imaging lens system in the camera module.

[0085] Conditional Expression 8 may provide a numerical range for limiting the focal length of the final lens. For example, the final lens exceeding the upper limit value of Conditional Expression 8 may have difficulty in performing the field curvature correction function, thereby deteriorating the aberration characteristics of the optical system.

[0086] Conditional Expression 9 may provide a numerical range for miniaturizing the imaging lens system. For example, an imaging lens system exceeding the numerical range of Conditional Expression 9 may have an excessively large difference between the effective diameter of the frontmost lens and the effective diameter of the rearmost lens, making it difficult to miniaturize the imaging lens system.

[0087] A camera module including an optical system according to an embodiment of the present disclosure may have a wide field of view and a low f-number, so an image stabilization function may not be required when capturing outdoor images, but an image shake correction function may be required when capturing photos at night or indoors. In this case, it may be desirable to configure the lens disposed closest to the imaging surface in the first lens group (or the lens closest to the image side of the optical path converter) to be responsible for camera shake correction. Conditional expression 10 provides a numerical range that limits the aberration stability of the correction lens responsible for camera shake correction. For example, a correction lens that exceeds the lower limit value of conditional expression 10 may have a small refractive power, which may result in an increase in the movement required for hand shake correction. As another example, a correction lens that exceeds the upper limit value of conditional expression 10 may have the problem of increasing the aberration of the imaging lens system. On the other hand, a correction lens that satisfies conditional expression 10 can stably maintain the resolution of the imaging lens system during the movement required for camera shake correction.

[0088] According to an embodiment of the present disclosure, an imaging lens system includes a plurality of lenses arranged in sequence from the object side, and one or more of the following conditional expressions may be satisfied. For example, an imaging lens system according to an embodiment of the present disclosure includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side, or the imaging lens system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side, or the imaging lens system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side, and one or more of the following conditional expressions may be satisfied.

[0089] 11)1.40 <D12 / f<2.20

[0090] 12)8.0 <R1 / R2<20

[0091] 13)-3.0<(R1+R4) / (R2+R3)<3.10

[0092] 14)0.80 <R5 / R7<1.60

[0093] 15)-6.0<(R3+R12) / R8<-1.0

[0094] 16)-3.0<(R3+R12) / (R8+R9)<-0.80

[0095] In the above conditional expressions, D12 is the distance from the image side surface of the first lens to the object side surface of the second lens, R1 is the curvature radius of the object side surface of the first lens, R2 is the curvature radius of the image side surface of the first lens, R3 is the curvature radius of the object side surface of the second lens, R4 is the curvature radius of the image side surface of the second lens, R5 is the curvature radius of the object side surface of the third lens, R7 is the curvature radius of the object side surface of the fourth lens, R8 is the curvature radius of the image side surface of the fourth lens, R9 is the curvature radius of the object side surface of the fifth lens, and R12 is the curvature radius of the image side surface of the sixth lens.

[0096] Conditional Expression 11 may be a numerical range for limiting the shape of the first lens group. For example, an imaging lens system exceeding the lower limit value of Conditional Expression 11 may have difficulty in forming a first lens group including an optical path converter. As another example, an imaging lens system exceeding the upper limit value of Conditional Expression 11 may have difficulty in miniaturizing.

[0097] Conditional expression 12 may be a numerical range for limiting the shape of the object side surface of the frontmost lens (or first lens). For example, it may be difficult to correct the aberration of the frontmost lens exceeding the lower limit value of conditional expression 12, and it may be difficult to manufacture the frontmost lens exceeding the upper limit value of conditional expression 12.

[0098] Conditional Expression 13 to Conditional Expression 16 may be a numerical range for improving aberration characteristics. For example, in an imaging lens system exceeding the numerical range of Conditional Expression 13 to Conditional Expression 16, it may be difficult to perform aberration correction by the first lens to the sixth lens.

[0099] According to an embodiment of the present disclosure, an imaging lens system includes a plurality of lenses arranged in sequence from the object side and may satisfy one or more of the following conditional expressions. For example, an imaging lens system according to an embodiment of the present disclosure may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged in sequence from the object side, or the imaging lens system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side, or the imaging lens system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens arranged in sequence from the object side, and may satisfy one or more of the following conditional expressions.

[0100] 17)-0.60 <f1 / f2<-0.10

[0101] 18)0.60<(f1+f2) / f3<1.20

[0102] 19)-1.20<(f1+f5) / f3<-0.80

[0103] 20)0.80 <f1 / f5<1.60

[0104] 21)0.80<(f3+f4) / f2<1.60

[0105] 22)-1.50<(f3-f4) / f5<-0.30

[0106] 23)0.40<(f3+f5) / f4<1.40

[0107] 24)1.0<(f1+f2) / R5<1.80

[0108] 25)1.0<(f2+R12) / (f3+R12)<1.40

[0109] In the above conditional expressions, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, and f5 is the focal length of the fifth lens.

[0110] Conditional Expression 17 to Conditional Expression 25 may be a numerical range for limiting the magnitude of the refractive power of the first lens to the sixth lens. For example, the first lens to the sixth lens outside the numerical range of Conditional Expression 17 to Conditional Expression 25 may make it difficult to realize an imaging lens system with a wide angle of view or a bright imaging lens system. As another example, for a shape outside the numerical range of Conditional Expression 17 to Conditional Expression 25, the resolution of the imaging lens system may be greatly reduced due to a rapid increase in aberrations.

[0111] According to an embodiment of the present disclosure, the imaging lens system may be configured to include one or more features according to an embodiment of the present disclosure. As an example, according to an embodiment of the present disclosure, the imaging lens system may include the characteristics of one embodiment and satisfy one or more of the conditional expressions according to another embodiment.

[0112] According to an embodiment of the present disclosure, the imaging lens system may include one or more lenses having the following characteristics as needed. As an example, according to an embodiment of the present disclosure, the imaging lens system may include one of the first lens to the eighth lens having the following characteristics. As another example, according to other embodiments of the present disclosure, the imaging lens system may include one or more of the first lens to the eighth lens having the following characteristics. However, according to an embodiment of the present disclosure, the imaging lens system does not necessarily include a lens having the following characteristics. Below, the characteristics of the first lens to the eighth lens will be described.

[0113] The first lens may have a refractive power. For example, the first lens may have a negative refractive power. The first lens may have a convex shape on one surface. For example, the first lens may have a convex object side surface. The first lens may include a spherical surface or an aspherical surface. For example, both surfaces of the first lens may be aspherical. The first lens may be made of a material having a high light transmittance and excellent processing properties. For example, the first lens may be made of plastic or glass. The first lens may be configured to have a predetermined refractive index. For example, the refractive index of the first lens may be greater than 1.5. As a specific example, the refractive index of the first lens may be greater than 1.50 and less than 1.6. The first lens may have a predetermined Abbe number. For example, the Abbe number of the first lens may be 50 or greater.

[0114] The second lens may have a refractive power. For example, the second lens may have a positive refractive power. The second lens may have a convex shape on one surface. For example, the second lens may have a convex object side surface. The second lens may include a spherical surface or an aspherical surface. For example, both surfaces of the second lens may be aspherical. The second lens may be made of a material having a high light transmittance and excellent processing properties. For example, the second lens may be formed of a plastic material or glass. The second lens may be configured to have a predetermined refractive index. For example, the refractive index of the second lens may be greater than 1.5. The second lens may have a predetermined Abbe number. For example, the Abbe number of the second lens may be 50 or greater.

[0115] The third lens may have a refractive power. For example, the third lens may have a positive refractive power. The third lens may have a convex shape on one surface. For example, the third lens may have a convex object side surface. The third lens may include a spherical surface or an aspherical surface. For example, both surfaces of the third lens may be aspherical. The third lens may be made of a material having a high light transmittance and excellent processing properties. For example, the third lens may be made of plastic. The third lens may be configured to have a predetermined refractive index. For example, the refractive index of the third lens may be greater than 1.5. The third lens may have a predetermined Abbe number. For example, the Abbe number of the third lens may be greater than 50.

[0116] The fourth lens may have a refractive power. For example, the fourth lens may have a positive refractive power. The fourth lens may have a convex shape on one surface. For example, the fourth lens may have a convex object side surface. The fourth lens may include a spherical surface or an aspherical surface. For example, both surfaces of the fourth lens may be spherical. The fourth lens may be made of a material having a high light transmittance and excellent processing properties. For example, the fourth lens may be made of plastic. The fourth lens may have a predetermined refractive index. For example, the refractive index of the fourth lens may be less than 1.52.

[0117] The fifth lens may have a refractive power. For example, the fifth lens may have a negative refractive power. The fifth lens may have a concave shape on one surface. As an example, the fifth lens may have a concave object side surface. The fifth lens may include a spherical surface or an aspherical surface. For example, both surfaces of the fifth lens may be spherical. The fifth lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the fifth lens may be made of plastic. The fifth lens may have a predetermined refractive index. As an example, the refractive index of the fifth lens may be greater than 1.8.

[0118] The sixth lens may have a refractive power. For example, the sixth lens may have a positive refractive power or a negative refractive power. The sixth lens may have a convex shape on one surface. As an example, the sixth lens may have a convex object side surface. The sixth lens may include a spherical surface or an aspherical surface. For example, both surfaces of the sixth lens may be aspherical. The sixth lens may have a shape with an inflection point. For example, the inflection point may be formed on at least one of the object side surface and the image side surface of the sixth lens. The sixth lens may be made of a material having a high light transmittance and excellent processing performance. For example, the sixth lens may be made of plastic. The sixth lens may be configured to have a predetermined refractive index. As an example, the refractive index of the sixth lens may be less than 1.7.

[0119] The seventh lens may have a refractive power. For example, the seventh lens may have a positive refractive power. The seventh lens may have a convex shape on one surface. As an example, the seventh lens may have a convex object side surface. The seventh lens may include a spherical surface or an aspherical surface. For example, both surfaces of the seventh lens may be aspherical. The seventh lens may have a shape with an inflection point. For example, the inflection point may be formed on at least one of the object side surface and the image side surface of the seventh lens. The seventh lens may be formed of a material having a high light transmittance and excellent processing performance. For example, the seventh lens may be formed of plastic. The seventh lens may be configured to have a predetermined refractive index. As an example, the refractive index of the seventh lens may be greater than 1.5. The seventh lens may have a predetermined Abbe number. For example, the Abbe number of the seventh lens may be greater than 50.

[0120] The eighth lens may have a refractive power. For example, the eighth lens may have a positive refractive power. The eighth lens may have a convex shape on one surface. As an example, the eighth lens may have a convex object side surface. The eighth lens may include a spherical surface or an aspherical surface. For example, both surfaces of the eighth lens may be aspherical. The eighth lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the eighth lens may be formed of a plastic material. The eighth lens may be configured to have a predetermined refractive index. As an example, the refractive index of the eighth lens may be greater than 1.5. The eighth lens may have a predetermined Abbe number. For example, the Abbe number of the eighth lens may be greater than 50.

[0121] As described above, the first to eighth lenses may include a spherical surface or an aspherical surface. When the first to eighth lenses include an aspherical surface, the aspherical surface of the corresponding lens may be expressed by Equation 1.

[0122] Equation 1:

[0123]

[0124] In Equation 1, c is the inverse of the radius of curvature of the corresponding lens, K is the conic constant, r is the distance from any point on the aspheric surface to the optical axis, A to H, J and L to P are aspheric surface constants, and Z (or SAG) is the height from a certain point on the aspheric surface to the vertex of the corresponding aspheric surface in the optical axis direction.

[0125] The imaging lens system according to the above embodiment or the above form may further include an aperture and a filter. The aperture may be arranged between the first lens group and the second lens group or between the third lens and the fourth lens. The filter may be arranged between the last lens (the sixth lens, the seventh lens or the eighth lens) and the imaging surface. The filter may be configured to block light of a specific wavelength. For reference, the filter described in this specification is configured to block infrared rays, but the wavelength of light blocked by the filter is not limited to infrared rays.

[0126] Hereinafter, specific embodiments of the present disclosure will be described in detail based on the accompanying drawings.

[0127] First, refer to Figure 1 and Figure 2 An imaging lens system according to an embodiment is described.

[0128] The imaging lens system 100 may have a plurality of lens groups. For example, the imaging lens system 100 may include a first lens group LG1 and a second lens group LG2. The first lens group LG1 and the second lens group LG2 may be arranged in sequence from the object side. The first lens group LG1 and the second lens group LG2 may include one or more lenses. For example, the first lens group LG1 may have two lenses, and the second lens group LG2 may have five lenses.

[0129] The first lens group LG1 may have a first lens 110 and a second lens 120. The first lens 110 may have a negative refractive power and may have a convex object-side surface and a concave image-side surface. The second lens 120 may have a positive refractive power and may have a convex object-side surface and a convex image-side surface. The first lens group LG1 may include an optical path converter. For example, the first lens group LG1 may include a prism P disposed between the first lens 110 and the second lens 120. For reference, in the present embodiment, the prism P is shown as a type of optical path converter, but the optical path converter may also be changed to a reflector.

[0130] The second lens group LG2 may have a third lens 130, a fourth lens 140, a fifth lens 150, a sixth lens 160, and a seventh lens 170. The third lens 130 may have positive refractive power, and may have a convex object side surface and a convex image side surface. The fourth lens 140 may have positive refractive power, and may have a convex object side surface and a convex image side surface. The fifth lens 150 may have negative refractive power, and may have a concave object side surface and a concave image side surface. The sixth lens 160 may have negative refractive power, and may have a convex object side surface and a concave image side surface. The seventh lens 170 may have positive refractive power, and may have a convex object side surface and a concave image side surface.

[0131] The second lens group LG2 can be configured to be movable in the optical axis direction. Therefore, according to the embodiment, the imaging lens system 100 can achieve focus adjustment (AF) of the camera module by moving the second lens group LG2. Specifically, in the present embodiment, the change in the size of the focal length (f) caused by the movement of the second lens group LG2 can be very small. Therefore, even if the focus is adjusted by the second lens group LG2, the imaging lens system 100 according to the present embodiment can achieve a constant quality resolution.

[0132] The imaging lens system 100 may further include other elements in addition to the first lens 110 to the seventh lens 170. For example, the imaging lens system 100 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the first lens group LG1 and the second lens group LG2. The filter IF may be disposed between the seventh lens 170 and the imaging surface IP. The imaging surface IP may be formed in a position where light incident from the first lens 110 to the seventh lens 170 forms an image. For example, the imaging surface IP may be formed on one surface of the image sensor IS of the camera module or on a lens element disposed inside the image sensor IS.

[0133] Figure 2 Aberration characteristics of the imaging lens system 100 according to the present embodiment are shown. Tables 1 and 2 show lens characteristics of the imaging lens system according to the present embodiment, and Table 3 shows lens characteristics and aspheric values ​​of the imaging lens system according to the present embodiment.

[0134] Table 1

[0135]

[0136]

[0137] Table 2

[0138]

[0139] Table 3

[0140]

[0141]

[0142] Will refer to Figure 3 and Figure 4 An imaging lens system according to an embodiment is described.

[0143] The imaging lens system 200 may include a plurality of lens groups. For example, the imaging lens system 200 may include a first lens group LG1 and a second lens group LG2. The first lens group LG1 and the second lens group LG2 may be arranged in sequence from the object side. The first lens group LG1 and the second lens group LG2 may include one or more lenses. For example, the first lens group LG1 may have two lenses, and the second lens group LG2 may have four lenses.

[0144] The first lens group LG1 may include a first lens 210 and a second lens 220. The first lens 210 may have a negative refractive power and may have a convex object-side surface and a concave image-side surface. The second lens 220 may have a positive refractive power and may have a convex object-side surface and a convex image-side surface. The first lens group LG1 may include an optical path converter. For example, the first lens group LG1 may include a prism P disposed between the first lens 110 and the second lens 120. For reference, in the present embodiment, the prism P is shown as a type of optical path converter, but it may also be possible to use a reflector as an optical path converter.

[0145] The second lens group LG2 may include a third lens 230, a fourth lens 240, a fifth lens 250, and a sixth lens 260. The third lens 230 may have positive refractive power and may have a convex object side surface and a convex image side surface. The fourth lens 240 may have positive refractive power and may have a convex object side surface and a convex image side surface. The fifth lens 250 may have negative refractive power and may have a concave object side surface and a concave image side surface. The sixth lens 260 may have negative refractive power and may have a convex object side surface and a concave image side surface.

[0146] The second lens group LG2 can be configured to be movable in the optical axis direction. Therefore, the imaging lens system 200 according to the present embodiment can realize the focus adjustment (AF) of the camera module by the movement of the second lens group LG2. Specifically, in the present embodiment, the change in the size of the focal length (f) caused by the movement of the second lens group LG2 can be very small. Therefore, even if the focus is adjusted by the second lens group LG2, the imaging lens system 200 according to the present embodiment can also achieve a constant quality resolution.

[0147] The imaging lens system 200 may further include other elements in addition to the first lens 210 to the sixth lens 260. For example, the imaging lens system 200 may further include an aperture ST, a filter IF, and an imaging surface IP. The aperture ST may be disposed between the third lens 230 and the fourth lens 240. The filter IF may be disposed between the sixth lens 260 and the imaging surface IP. The imaging surface IP may be formed in a position where light incident from the first lens 210 to the sixth lens 260 forms an image. For example, the imaging surface IP may be formed on one surface of the image sensor IS of the camera module or on a lens element disposed inside the image sensor IS.

[0148] Figure 4 Aberration characteristics of the imaging lens system 200 according to the present embodiment are shown. Tables 4 and 5 show lens characteristics of the imaging lens system according to the present embodiment, and Table 6 shows lens characteristics and aspheric values ​​of the imaging lens system according to the present embodiment.

[0149] Table 4

[0150]

[0151]

[0152] Table 5

[0153]

[0154] Table 6

[0155]

[0156]

[0157] Will refer to Figure 5 and Figure 6 An imaging lens system according to an embodiment is described.

[0158] The imaging lens system 300 may include a plurality of lens groups. For example, the imaging lens system 300 may include a first lens group LG1 and a second lens group LG2. The first lens group LG1 and the second lens group LG2 may be arranged in sequence from the object side. The first lens group LG1 and the second lens group LG2 may include one or more lenses. For example, the first lens group LG1 may have two lenses, and the second lens group LG2 may have four lenses.

[0159] The first lens group LG1 may include a first lens 310 and a second lens 320. The first lens 310 may have a negative refractive power and may have a convex object side surface and a concave image side surface. The second lens 320 may have a positive refractive power and may have a convex object side surface and a convex image side surface. The first lens group LG1 may include an optical path converter. For example, the first lens group LG1 may include a reflector M disposed between the first lens 310 and the second lens 320. For reference, in the present embodiment, the reflector M is shown as a type of optical path converter, but the optical path converter may also be changed to a prism.

[0160] The second lens group LG2 may include a third lens 330, a fourth lens 340, a fifth lens 350, and a sixth lens 360. The third lens 330 may have positive refractive power, and may have a convex object side surface and a convex image side surface. The fourth lens 340 may have positive refractive power, and may have a convex object side surface and a convex image side surface. The fifth lens 350 may have negative refractive power, and may have a concave object side surface and a convex image side surface. The sixth lens 360 may have positive refractive power, and may have a convex object side surface and a concave image side surface.

[0161] The second lens group LG2 can be configured to be movable in the optical axis direction. Therefore, the imaging lens system 300 according to the present embodiment can realize the focus adjustment (AF) of the camera module by the movement of the second lens group LG2. Specifically, in the present embodiment, the change in the size of the focal length (f) caused by the movement of the second lens group LG2 can be very small. Therefore, even if the focus is adjusted by the second lens group LG2, the imaging lens system 300 according to the present embodiment can also achieve a constant quality resolution.

[0162] The imaging lens system 300 may further include other elements in addition to the first lens 310 to the sixth lens 360. For example, the imaging lens system 300 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the first lens group LG1 and the second lens group LG2. The filter IF may be disposed between the sixth lens 360 and the imaging surface IP. The imaging surface IP may be formed in a position where light incident from the first lens 310 to the sixth lens 360 forms an image. For example, the imaging surface IP may be formed on a surface of the image sensor IS of the camera module or on a lens element disposed inside the image sensor IS.

[0163] Figure 6 The aberration characteristics of the imaging lens system 300 according to the present embodiment are shown. Tables 7 and 8 show the lens characteristics of the imaging lens system according to the present embodiment, and Table 9 shows the lens characteristics and aspheric surface values ​​of the imaging lens system according to the present embodiment.

[0164] Table 7

[0165]

[0166]

[0167] Table 8

[0168]

[0169] Table 9

[0170]

[0171]

[0172] Will refer to Figure 7 and Figure 8 An imaging lens system according to an embodiment is described.

[0173] The imaging lens system 400 may include a plurality of lens groups. For example, the imaging lens system 400 may include a first lens group LG1 and a second lens group LG2. The first lens group LG1 and the second lens group LG2 may be arranged in sequence from the object side. The first lens group LG1 and the second lens group LG2 may include one or more lenses. For example, the first lens group LG1 may have two lenses, and the second lens group LG2 may have six lenses.

[0174] The first lens group LG1 may include a first lens 410 and a second lens 420. The first lens 410 may have a negative refractive power and may have a convex object-side surface and a concave image-side surface. The second lens 420 may have a positive refractive power and may have a convex object-side surface and a convex image-side surface. The first lens group LG1 may include an optical path converter. For example, the first lens group LG1 may include a prism P disposed between the first lens 410 and the second lens 420. For reference, in the present embodiment, the prism P is shown as a type of optical path converter, but any other optical path converter such as a reflector may be used.

[0175] The second lens group LG2 may include a third lens 430, a fourth lens 440, a fifth lens 450, a sixth lens 460, a seventh lens 470, and an eighth lens 480. The third lens 430 may have a positive refractive power and may have a convex object side surface and a convex image side surface. The fourth lens 440 may have a positive refractive power and may have a convex object side surface and a convex image side surface. The fifth lens 450 may have a negative refractive power and may have a concave object side surface and a convex image side surface. The sixth lens 460 may have a negative refractive power and may have a convex object side surface and a concave image side surface. The seventh lens 470 may have a positive refractive power and may have a convex object side surface and a concave image side surface. The eighth lens 480 may have a positive refractive power and may have a convex object side surface and a concave image side surface.

[0176] The second lens group LG2 can be configured to be movable in the optical axis direction. Therefore, according to this embodiment, the imaging lens system 400 can achieve focus adjustment (AF) of the camera module by moving the second lens group LG2. Specifically, in this embodiment, the change in the size of the focal length (f) caused by the movement of the second lens group LG2 can be very small. Therefore, even if the focus is adjusted by the second lens group LG2, the imaging lens system 400 according to this embodiment can also achieve a constant quality resolution.

[0177] The imaging lens system 400 may further include other elements in addition to the first lens 410 to the eighth lens 480. For example, the imaging lens system 400 may further include an aperture ST, an optical filter IF, and an imaging surface IP. The aperture ST may be disposed between the first lens group LG1 and the second lens group LG2. The optical filter IF may be disposed between the eighth lens 480 and the imaging surface IP. The imaging surface IP may be formed at a position where light incident from the first lens 410 to the eighth lens 480 forms an image. For example, the imaging surface IP may be formed on a surface of the image sensor IS of the camera module or on a lens element disposed inside the image sensor IS.

[0178] Figure 8 Aberration characteristics of the imaging lens system 400 according to the present embodiment are shown. Tables 10 and 11 show lens characteristics of the imaging lens system according to the present embodiment, and Table 12 shows lens characteristics and aspheric surface values ​​of the imaging lens system according to the present embodiment.

[0179] Table 10

[0180]

[0181]

[0182] Table 11

[0183]

[0184]

[0185] Table 12

[0186]

[0187] Table 13 shows characteristic values ​​of the imaging lens system according to the embodiment of the present disclosure.

[0188] Table 13

[0189]

[0190]

[0191] According to an example of an embodiment of the present disclosure, the imaging lens system according to the present disclosure may have specific lens characteristics. For example, the focal length of the first lens is determined within the range of -10.0 mm to -4.0 mm, the focal length of the second lens is determined within the range of 10.0 mm to 24.0 mm, the focal length of the third lens is determined within the range of 7.0 mm to 24.0 mm, the focal length of the fourth lens is determined within the range of 4.0 mm to 9.0 mm, the focal length of the fifth lens is determined within the range of -8.0 mm to -3.0 mm, the focal length of the sixth lens may be determined to be -10.0 mm or less or 60.0 mm or more, the focal length of the seventh lens may be determined to be 10.0 mm or more, and the focal length of the eighth lens may be determined to be 40 mm or more.

[0192] Tables 14 to 16 show conditional expression values ​​of the imaging lens system according to the embodiment of the present disclosure.

[0193] Table 14

[0194]

[0195] Table 15

[0196]

[0197]

[0198] Table 16

[0199]

[0200] Will refer to Fig.10 An electronic device according to an embodiment is described.

[0201] The electronic device 10 according to an embodiment of the present disclosure may include a camera module. As an example, the electronic device 10 may be a portable terminal including camera modules 20 and 30. However, the form of the electronic device 10 is not limited to a portable terminal. As an example, the electronic device 10 may include any portable electronic device such as a laptop computer or a tablet PC. The electronic device 10 according to an embodiment may include one or more of the imaging lens systems 100, 200, 300, and 400 according to an embodiment of the present disclosure. As an example, at least one of the first camera module 20 and the second camera module 30 mounted on one side of the electronic device 10 may be the imaging lens systems 100, 200, 300, and 400 according to an embodiment of the present disclosure.

[0202] The present disclosure can significantly reduce the resolution degradation caused by the change of the position of the lens or lens group.

[0203] Furthermore, the present disclosure can capture images of objects at infinite distance and nearby objects at a constant resolution.

[0204] Although specific examples have been shown and described above, it will be apparent after understanding the present disclosure that various changes in form and detail may be made to these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are understood in a descriptive sense only and not for limiting purposes. The description of the features or aspects in each example should be considered to be applicable to similar features or aspects in other examples. If the described techniques are performed in a different order, and / or if the components in the described system, architecture, device or circuit are replaced or supplemented in a different manner and / or by other components or their equivalents, appropriate results can still be achieved. Therefore, the scope of the present disclosure is not limited by specific embodiments, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents should be understood to be included in the present disclosure.

Claims

1. An imaging lens system, comprising: A first lens group including one or more lenses; And A second lens group including one or more lenses and configured to be movable in the optical axis direction, Wherein the first lens group and the second lens group are arranged in sequence from the object side, Wherein the imaging lens system satisfies: 2.80 ≤ fG1R / f ≤ 4.0, Wherein f is the focal length of the imaging lens system, and fG1R is the focal length of the first rear lens disposed closest to the imaging surface in the first lens group, and Wherein at least one lens in the first lens group and / or the second lens group includes an aspherical surface.

2. The imaging lens system according to claim 1, wherein: The first rear lens has a convex image side surface.

3. The imaging lens system according to claim 1, wherein: The first lens group has a total of two lenses.

4. The imaging lens system according to claim 1, wherein: The second lens group has a total of four, five or six lenses.

5. The imaging lens system according to claim 1, wherein: The last lens disposed closest to the imaging surface has a positive refractive power.

6. The imaging lens system according to claim 1, wherein: The frontmost lens disposed closest to the object has a negative refractive power.

7. The imaging lens system according to claim 1, satisfying: -1.50 < fF / f < -1.20, in, fF is the focal length of the frontmost lens disposed closest to the object.

8. An imaging lens system, comprising: A first lens, an optical path converter, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in sequence from the object side, Wherein the imaging lens system satisfies: 2.80 ≤ f2 / f ≤ 4.0, and 1.40 < D12 / f < 2.20, Wherein f is the focal length of the imaging lens system, f2 is the focal length of the second lens, and D12 is the distance from the image side surface of the first lens to the object side surface of the second lens, and Wherein at least one lens among the first lens to the sixth lens includes an aspherical surface.

9. The imaging lens system according to claim 8, wherein: The first lens has a convex object side surface.

10. The imaging lens system according to claim 8, wherein: The second lens has a convex object side surface.

11. The imaging lens system according to claim 8, wherein: The third lens has a convex object side surface.

12. The imaging lens system according to claim 8, wherein: The fourth lens has a convex object side surface.

13. The imaging lens system according to claim 8, wherein: The fifth lens has a concave object side surface.

14. The imaging lens system according to claim 8, wherein: The sixth lens has a convex object side surface.

15. The imaging lens system according to claim 8, wherein: The imaging lens system further includes a seventh lens disposed on the image side of the sixth lens.

16. The imaging lens system according to claim 15, wherein: The seventh lens has a convex object side surface.

17. An imaging lens system, comprising: A first lens group including one or more lenses; And A second lens group including one or more lenses and configured to be movable in the optical axis direction, Wherein the first lens group and the second lens group are arranged in sequence from the object side, Wherein the imaging lens system satisfies -1.5 < f1 / f < -1.20 and 2.80 ≤ f2 / f ≤ 4.0, Wherein f is the focal length of the imaging lens system, f1 is the focal length of the first lens of the imaging lens system, and f2 is the focal length of the second lens of the imaging lens system, and Wherein at least one lens in the first lens group and / or the second lens group includes an aspherical surface.

18. The imaging lens system according to claim 17, wherein: The first rear lens disposed closest to the imaging surface in the first lens group has a convex image side surface.

19. The imaging lens system according to claim 17, wherein: The first lens group has a total of two lenses.

20. The imaging lens system of claim 17, wherein: The second lens group has a total of four, five or six lenses, and Wherein, the last lens disposed closest to the imaging plane in the second lens group has positive refractive power.

Images