Imaging lens system

Abstract

The imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in order from an object side. The seventh lens has a convex image side surface, the eighth lens has a positive refractive power, and the imaging lens system satisfies the following conditional expressions: 1.10 lt; f3 / flt; f is the focal length of the imaging lens system, and f3 is the focal length of the third lens.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority of Korean Patent Application No. 10 - 2023 - 0146727, filed on October 30, 2023, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical field

[0003] The present disclosure relates to an imaging lens system capable of achieving constant optical performance regardless of temperature changes in the surrounding environment. Background art

[0004] A small surveillance camera can be configured to capture image information within a surveillance area. For example, a small surveillance camera can be installed on the front bumper, rear bumper, etc. of a vehicle and can provide the captured images to a driver.

[0005] Early small surveillance cameras were designed to capture images of obstacles in neighboring vehicles and thus not only had relatively low resolution but also had a large variation in resolution with temperature changes from - 40 to 80 °C. However, as the requirements for autonomous driving functions of vehicles are increasing, it may be necessary to develop surveillance cameras with high resolution and constant optical characteristics even under harsh temperature conditions.

[0006] The above information is presented as background information only to help understand the present disclosure. No determination has been made, nor is any assertion made, as to whether any of the above constitutes prior art with respect to the present disclosure. Summary of the invention

[0007] The Summary of the Invention section is intended to introduce, in a brief form, a selection of concepts that will be further described in the Detailed Description section below. The Summary of the Invention section is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to help determine the scope of the claimed subject matter.

[0008] In one general aspect, an imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens sequentially arranged from the object side. The seventh lens has a convex image - side surface, the eighth lens has a positive refractive power, and the imaging lens system satisfies the following conditional expression: 1.10 < f3 / f < 1.40, where f is the focal length of the imaging lens system and f3 is the focal length of the third lens.

[0009] The first lens may have a concave image - side surface.

[0010] The second lens may have a convex image - side surface.

[0011] The third lens may have a convex image side surface.

[0012] The fourth lens may have a concave image side surface.

[0013] The fifth lens may have a convex image side surface.

[0014] The sixth lens may have a concave image side surface.

[0015] The camera module may include: a housing; a lens barrel disposed in the housing and accommodating an imaging lens system; and an image sensor disposed in the housing at the imaging surface of the imaging lens system.

[0016] The connection point of the lens barrel and the housing may be closer to the object side than the image side surface of the eighth lens, and the camera module may satisfy one or more of the following conditional expressions: 0.60 < BFL / CP < 0.82, and 0.80 < f3 / CP < 1.0, where CP is the connection point of the lens barrel and the housing, and BFL is the distance from the image side surface of the eighth lens to the imaging surface.

[0017] In another general aspect, the imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens sequentially arranged from the object side, where the imaging lens system satisfies the following conditional expression: 1.0 < (L1DTn + L4DTn) / (L5DTn + L8DTn) < 1.4, where L1DTn is the refractive index change rate according to temperature change of the first lens, L4DTn is the refractive index change rate according to temperature change of the fourth lens, L5DTn is the refractive index change rate according to temperature change of the fifth lens, and L8DTn is the refractive index change rate according to temperature change of the eighth lens.

[0018] The seventh lens may have a convex image side surface.

[0019] The imaging lens system may satisfy the following conditional expression: 4.0(10 -6 / ℃) < |L3DTn| < 8.0(10 -6 / ℃), where L3DTn is the refractive index change rate according to temperature change of the third lens.

[0020] The camera module may include: a housing; a lens barrel disposed in the housing and accommodating an imaging lens system; and an image sensor disposed in the housing at the imaging surface of the imaging lens system, where the lens barrel may have a first coefficient of thermal expansion, and the housing may have a second coefficient of thermal expansion different from the first coefficient of thermal expansion.

[0021] In another general aspect, an imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in order from an object side, wherein the seventh lens has a convex image side surface, wherein the eighth lens has a positive refractive power, and wherein the imaging lens system satisfies the following conditional expression: 4.0(10 -6 / ℃)<|L3DTn|<8.0(10 -6 / °C), where L3DTn is the refractive index changing rate of the third lens according to temperature change.

[0022] Other features and aspects will be apparent from the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a configuration diagram of an imaging lens system according to a first embodiment of the present disclosure.

[0024] Figure 2 yes Figure 1 Aberration curves of the imaging lens system shown in .

[0025] Figure 3 yes Figure 1 MTF curve of the imaging lens system shown in .

[0026] Figure 4 It is shown Figure 1 Graph of the back focal length (BFL) of the imaging lens system shown in FIG. 1 according to temperature variation.

[0027] Figure 5 is a configuration diagram of an imaging lens system according to a second embodiment of the present disclosure.

[0028] Figure 6 yes Figure 5 Aberration curves of the imaging lens system shown in .

[0029] Figure 7 yes Figure 5 MTF curve of the imaging lens system shown in .

[0030] Figure 8 It is shown Figure 5 Graph of BFL according to temperature variation of the imaging lens system shown in FIG.

[0031] Fig. 9 is a configuration diagram of an imaging lens system according to a third embodiment of the present disclosure.

[0032] Fig.10 yes Fig. 9 Aberration curves of the imaging lens system shown in .

[0033] Fig.11 yes Fig. 9 MTF curve of the imaging lens system shown in .

[0034] Fig.12 It is shown Fig. 9 Graph of BFL according to temperature variation of the imaging lens system shown in FIG.

[0035] Fig.13 is a configuration diagram of an imaging lens system according to a fourth embodiment of the present disclosure.

[0036] Fig.14 yes Fig.13 Aberration curves of the imaging lens system shown in .

[0037] Fig.15 yes Fig.13 MTF curve of the imaging lens system shown in .

[0038] Fig.16 It is shown Fig.13 Graph of BFL according to temperature variation of the imaging lens system shown in FIG.

[0039] Fig.17 is a configuration diagram of an imaging lens system according to a fifth embodiment of the present disclosure.

[0040] Fig.18 yes Fig.17 Aberration curves of the imaging lens system shown in .

[0041] Fig.19 yes Fig.17 MTF curve of the imaging lens system shown in .

[0042] Fig. 20 It is shown Fig.17 Graph of BFL according to temperature variation of the imaging lens system shown in FIG.

[0043] Fig.21 is a configuration diagram of an imaging lens system according to a sixth embodiment of the present disclosure.

[0044] Fig. 22 yes Fig.21 Aberration curves of the imaging lens system shown in .

[0045] Fig.23 yes Fig.21 MTF curve of the imaging lens system shown in .

[0046] Fig.24 It is shown Fig.21 Graph of BFL according to temperature variation of the imaging lens system shown in FIG.

[0047] Fig.25 is a configuration diagram of an imaging lens system according to a seventh embodiment of the present disclosure.

[0048] Fig.26 yes Fig.25 Aberration curves of the imaging lens system shown in .

[0049] Fig. 27 yes Fig.25 MTF curve of the imaging lens system shown in .

[0050] Fig.28 It is shown Fig.25 Graph of BFL according to temperature variation of the imaging lens system shown in FIG.

[0051] Fig.29 is a cross-sectional view of a camera module including an imaging lens system according to an embodiment of the present disclosure.

[0052] 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

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] The terms used herein are only used to describe various examples and are not used 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, numbers, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, numbers, operations, components, elements and / or combinations thereof.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] In the present disclosure, the first lens refers to the lens closest to the object (or subject), and the eighth lens refers to the lens closest to the imaging plane (or image sensor). In the present disclosure, the units of the radius of curvature, thickness, distance from the object side of the first lens to the imaging plane (TTL), height of the imaging plane (IMG HT), and focal length are expressed in millimeters (mm). In addition, the units of the refractive index change rate (DTn) and thermal expansion coefficient (CTE) described in this specification may be 10 -6 / ℃.

[0065] The thickness of the lens, the gap between lenses, and TTL refer to the distance along the optical axis. In addition, in the description of the lens shape, a configuration in which one surface is convex means that the paraxial area of ​​the surface is convex, and a configuration in which one surface is concave means that the paraxial area of ​​the surface is concave.

[0066] Thus, even when one surface of a lens is described as convex, the edge of the lens may be concave. Similarly, even when one surface of a lens is described as concave, the edge of the lens may be convex.

[0067] One aspect of the present disclosure may be to solve the above-mentioned problems and to provide an imaging lens system capable of achieving high resolution by using both a plastic lens and a glass lens while suppressing the amplitude of focus variation due to rapid temperature deviation to 10 micrometers (μm) or less.

[0068] The imaging lens system according to the first aspect of the present disclosure may include a plurality of lenses. For example, the imaging lens system according to the first aspect may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in order from the object side. The imaging lens system according to the first aspect may include a lens having a convex image side surface. For example, in the imaging lens system according to the first aspect, the seventh lens may have a convex image side surface. The imaging lens system according to the first aspect may include a lens having a positive refractive power. For example, in the imaging lens system according to the first aspect, the eighth lens may have a positive refractive power. The imaging lens system according to the first aspect may satisfy a specific conditional expression. For example, the imaging lens system according to the first aspect may satisfy the conditional expression 1.10 < f3 / f < 1.40, where f is the focal length of the imaging lens system, and f3 is the focal length of the third lens.

[0069] The imaging lens system according to the second aspect of the present disclosure may include a plurality of lenses. For example, the imaging lens system according to the second aspect may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in order from the object side. The imaging lens system according to the second aspect may satisfy a specific conditional expression. For example, the imaging lens system according to the second aspect may satisfy the conditional expression 1.0 < (L1DTn + L4DTn) / (L5DTn + L8DTn) < 1.4. In this conditional expression, L1DTn is the refractive index change rate of the first lens according to temperature change, L4DTn is the refractive index change rate of the fourth lens according to temperature change, L5DTn is the refractive index change rate of the fifth lens according to temperature change, and L8DTn is the refractive index change rate of the eighth lens according to temperature change.

[0070] The imaging lens system according to the third aspect of the present disclosure may include a plurality of lenses. For example, the imaging lens system according to the third aspect may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged sequentially from the object side. The imaging lens system according to the third aspect may include an aperture stop. For example, the imaging lens system according to the third aspect may include an aperture stop disposed between the second lens and the third lens. The imaging lens system according to the third aspect may include a lens having a convex image side surface. For example, in the imaging lens system according to the third aspect, the seventh lens may have a convex image side surface. The imaging lens system according to the third aspect may include a lens having a positive refractive power. For example, in the imaging lens system according to the third aspect, the eighth lens may have a positive refractive power. The imaging lens system according to the third aspect may be configured to minimize focal length changes due to temperature changes. For example, the imaging lens system according to the third aspect may satisfy conditional expression 4.0 <L3DTn<8.0(10 -6 / °C), where L3DTn is the refractive index changing rate of the third lens according to temperature change.

[0071] The imaging lens system according to the fourth aspect of the present disclosure may include a first lens to an eighth lens arranged sequentially from the object side, and may satisfy one or more of the following conditional expressions:

[0072] 2.60 <f2 / f<4.60

[0073] 1.0 <f3 / f<1.40

[0074] -2.40 <f4 / f<-1.20

[0075] In the conditional expression, f2 is the focal length of the second lens, and f4 is the focal length of the fourth lens.

[0076] An imaging lens system according to a fifth aspect of the present disclosure includes a first lens to an eighth lens arranged in order from the object side, and may satisfy one or more of the following conditional expressions:

[0077] -1.0 <f1 / f3<-0.6

[0078] 2.40 <f2 / f3<4.20

[0079] -2.0 <f4 / f3<-1.0

[0080] 1.0 <f5 / f3<2.0

[0081] -3.0 <f6 / f3<-2.0

[0082] 1.60 <f7 / f3<5.20

[0083] 0.80 <f7 / f8<1.20

[0084] 0.30 <f8 / (f3+f5+f7)<2.0

[0085] -14.0<(f1+f2) / (f3+f4)<-3.0

[0086] In the conditional expression, f1 is the focal length of the first lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, f7 is the focal length of the seventh lens, and f8 is the focal length of the eighth lens.

[0087] An imaging lens system according to a sixth aspect of the present disclosure includes a first lens to an eighth lens arranged in order from the object side, and may satisfy one or more of the following conditional expressions:

[0088] 0.80 <BFL / IMG HT<1.40

[0089] 2.0<(f3+BFL) / f<2.40

[0090] -3.80 <R7 / R12<-2.40

[0091] 0.60 <R7 / R14<1.20

[0092] -0.80 <R14 / f7<-0.30

[0093] -1.0 <R14 / f8<-0.10

[0094] 0.20 <R15 / f8<0.80

[0095] In the conditional expression, BFL is the distance from the image side surface of the last lens (eighth lens) to the imaging plane, IMG HT is the height of the imaging plane, R7 is the curvature radius of the object side surface of the fourth lens, R12 is the curvature radius of the image side surface of the sixth lens, and R14 is the curvature radius of the image side surface of the seventh lens.

[0096] An imaging lens system according to a seventh aspect of the present disclosure includes a first lens to an eighth lens arranged in order from the object side, and may satisfy one or more of the following conditional expressions:

[0097] 4.0 <L3DTn<8.0

[0098] 0.42 <L1DTn / L3DTn<1.0

[0099] 1.0<(L1DTn+L4DTn) / (L5DTn+L8DTn)<1.40

[0100] 0.92<(L4DTn+L5DTn) / (L6DTn+L7DTn)<1.20

[0101] In the conditional expression, L6DTn is the refractive index change rate of the sixth lens according to temperature change, and L7DTn is the refractive index change rate of the seventh lens according to temperature change.

[0102] The imaging lens system according to the eighth aspect of the present disclosure includes two or more of the first to seventh aspects having the following characteristics. For example, the imaging lens system according to the eighth aspect may include the characteristics of the first aspect and may satisfy one or more conditional expressions according to the fifth aspect. As another example, the imaging lens system according to the eighth aspect may include the characteristics of the second aspect and may satisfy one or more conditional expressions according to the sixth or seventh aspect.

[0103] The imaging lens system according to the first aspect to the eighth aspect may include one or more lenses having the following characteristics as needed. As an example, the imaging lens system according to the first aspect may include one of the first lens to the eighth lens having the following characteristics. As another example, the imaging lens system according to the second aspect may include two or more of the first lens to the eighth lens having the following characteristics. However, the imaging lens system according to the above aspects does not necessarily include a lens having the following characteristics. In the following, the characteristics of the first lens to the eighth lens will be described.

[0104] 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 concave shape on one surface. For example, the first lens may have a concave image side surface. The first lens may include a spherical surface or an aspherical surface. For example, both surfaces of the first lens may be spherical. The first lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the first lens may be formed of glass. The first lens may be configured to have characteristics that are conducive to improving aberrations. For example, the first lens may have a refractive index of 1.75 or greater and an Abbe number of 45 or greater.

[0105] 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 image side surface. The second lens may include an aspherical surface. For example, both surfaces of the second lens may be aspherical. The second lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the second lens may be formed of a plastic material. The second lens may have a predetermined refractive index. For example, the refractive index of the second lens may be 1.64 or greater. The second lens may have a predetermined Abbe number. For example, the Abbe number of the second lens may be greater than 20 and less than 30.

[0106] 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 image side surface. The third lens may include an aspherical surface. For example, both surfaces of the third lens may be aspherical. The third lens may be formed of a material having a high light transmittance and excellent processing performance. For example, the third lens may be formed of glass. The third lens may be configured to have characteristics that are conducive to improving aberrations. For example, the third lens may have a refractive index of 1.70 or greater and an Abbe number of 45 or greater.

[0107] The fourth lens may have a refractive power. For example, the fourth lens may have a negative refractive power. The fourth lens may have a concave shape on one surface. For example, the fourth lens may have a concave image side surface. The fourth lens may include an aspherical surface. For example, both surfaces of the fourth lens may be aspherical. The fourth lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the fourth lens may be formed of a plastic material. The fourth lens may have a predetermined refractive index. For example, the refractive index of the fourth lens may be 1.6 or greater. The fourth lens may have a predetermined Abbe number. For example, the Abbe number of the fourth lens may be greater than 20 and less than 30.

[0108] The fifth lens may have a refractive power. For example, the fifth lens may have a positive refractive power. The fifth lens may have a convex shape on one surface. For example, the fifth lens may have a convex image side surface. The fifth lens may include an aspherical surface. For example, both surfaces of the fifth lens may be aspherical. 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 formed of a plastic material. The fifth lens may have a predetermined refractive index. For example, the refractive index of the fifth lens may be less than 1.6. The fifth lens may have a predetermined Abbe number. For example, the Abbe number of the fifth lens may be greater than 50 and less than 60.

[0109] The sixth lens may have a refractive power. For example, the sixth lens may have a negative refractive power. The sixth lens may have a concave shape on one surface. For example, the sixth lens may have a concave image side surface. The sixth lens may include an aspherical surface. For example, both surfaces of the sixth lens may be aspherical. The sixth lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the sixth lens may be formed of a plastic material. The sixth lens may have a predetermined refractive index. For example, the refractive index of the sixth lens may be substantially the same as or similar to the refractive index of the fourth lens. The sixth lens may have a predetermined Abbe number. For example, the Abbe number of the sixth lens may be substantially the same as or similar to the Abbe number of the fourth lens.

[0110] 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. For example, the seventh lens may have a convex image side surface. The seventh lens may include an aspherical surface. For example, both surfaces of the seventh lens may be aspherical. The seventh lens may be formed of a material having a high light transmittance and excellent processing properties. For example, the seventh lens may be formed of a plastic material. The seventh lens may have a predetermined refractive index. As an example, the refractive index of the seventh lens may be substantially the same as or similar to the refractive index of the fifth lens. The seventh lens may have a predetermined Abbe number. For example, the Abbe number of the seventh lens may be substantially the same as or similar to the Abbe number of the fifth lens.

[0111] The eighth lens may have a refractive power. For example, the eighth lens may have a positive refractive power or a negative refractive power. The eighth lens may have a convex shape on one surface. For example, the eighth lens may have a convex object side surface. The eighth lens may include 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 glass. The eighth lens may have a predetermined refractive index. For example, the refractive index of the eighth lens may be 1.56 or greater. The eighth lens may have a predetermined Abbe number. For example, the Abbe number of the eighth lens may be 60 or greater.

[0112] The aspherical lens constituting the imaging lens system can be expressed by the following equation 1:

[0113] Equation 1

[0114]

[0115] In Equation 1, c is the inverse of the radius of curvature of the corresponding lens, k is a conic constant, r is the distance from an arbitrary point on the aspherical surface to the optical axis, A, B, C, D and E are aspherical constants, and Z is the height from a certain point on the aspherical surface to the vertex of the corresponding aspherical surface in the optical axis direction.

[0116] The imaging lens system may include lenses formed of different materials. For example, the first lens, the third lens, and the eighth lens may be formed of a material different from that of the second lens and the fourth lens to the seventh lens. As a specific example, the first lens, the third lens, and the eighth lens are formed of a glass material having a low thermal expansion coefficient to external impact and temperature change, and the second lens and the fourth lens to the seventh lens are formed of a plastic material that is easy to process. However, the materials of the first lens to the eighth lens are not limited to the above examples. For example, the first lens and the third lens may be formed of a glass material, and the second lens and the fourth lens to the eighth lens may be formed of a plastic material.

[0117] The imaging lens system may include an aperture, an imaging surface, and a filter.

[0118] The aperture may be disposed between the lenses. For example, the aperture may be disposed between the second lens and the third lens. As another example, the aperture may be disposed on the image side of a lens having positive refractive power, or between a lens having positive refractive power and a lens having positive refractive power. An imaging plane may be formed at a point where the light refracted by the first lens to the eighth lens forms an image. The imaging plane may be formed by an image sensor. For example, the imaging plane may be formed on the surface of the image sensor or on the inner side of the image sensor. An optical filter may be disposed between the eighth lens and the imaging plane. The optical filter may block light of a specific wavelength. For example, the optical filter may block light of an infrared wavelength.

[0119] The camera module according to the ninth aspect of the present disclosure may include one of the imaging lens systems according to the first to eighth aspects. For example, the camera module according to the ninth aspect may include the imaging lens system according to the first aspect. The camera module according to the ninth aspect may include a lens barrel and a housing. In the camera module according to the ninth aspect, the lens barrel may be configured to accommodate the imaging lens system, and the housing may be configured to accommodate the lens barrel and the image sensor. In the camera module according to the ninth aspect, the lens barrel and the housing may be formed of different materials or materials with different thermal expansion coefficients. For example, the lens barrel may be formed of a plastic material, and the housing may be formed of a metal material. As another example, the lens barrel may be formed of a 6×10 -5 / ℃, and the housing may be formed of a material having a CTE of 2.3×10 -5 / ℃ CTE of the material is formed.

[0120] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying illustrative drawings.

[0121] First, refer to Figure 1 An imaging lens system according to a first embodiment is described.

[0122] The imaging lens system 100 may include a first lens 110 , a second lens 120 , a third lens 130 , a fourth lens 140 , a fifth lens 150 , a sixth lens 160 , a seventh lens 170 , and an eighth lens 180 .

[0123] The first lens 110 may have negative refractive power and may have a convex object side surface and a concave image side surface. The second lens 120 may have positive refractive power and may have a concave object side surface and a convex image side surface. 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 negative refractive power and may have a concave object side surface and a concave image side surface. The fifth lens 150 may have positive refractive power and may have a convex object side surface and a convex 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 convex image side surface. The eighth lens 180 may have positive refractive power and may have a convex object side surface and a concave image side surface.

[0124] 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 second lens 120 and the third lens 130. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 180 and the imaging surface IP.

[0125] Figure 2 shows aberration curves of the imaging lens system according to the present embodiment, and Figure 3 and Figure 4 Modulation transfer function (MTF) characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0126] Table 1 and Table 2 show lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0127] Table 1

[0128] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens 300.000 0.845 1.7725 49.62 3.6 8.0 S2 4.979 2.356 S3 Second lens -19.349 2.894 1.6561 21.24 -120.0 66.0 S4 -8.854 0.107 S5 Aperture infinity 1.985 - - - - S6 The third lens 17.996 2.907 1.739 49.06 7.5 6.0 S7 -8.576 0.565 S8 The fourth lens -16.650 1.000 1.6561 21.24 -120.0 66.0 S9 12.663 0.173 S10 Fifth lens 145.875 2.985 1.5365 56.5 -95.7 60.0 S11 -7.465 0.126 S12 The sixth lens 9.323 1.748 1.6561 21.24 -120.0 66.0 S13 5.318 0.895 S14 Seventh lens 115.713 2.905 1.5365 56.5 -95.7 60.0 S15 -22.010 0.133 S16 The eighth lens 7.612 2.463 1.5909 67.17 -2.0 9.7 S17 12.009 3.215 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 1.000 S20 infinity 0.446 - - - - S21 Imaging surface infinity 0.000 - - - -

[0129] Table 2

[0130] Face number k A B C D E S3 0 -1.069E-03 -3.207E-05 1.972E-06 -1.716E-07 0 S4 0 -6.829E-04 1.549E-05 -9.068E-07 4.245E-10 0 S6 0 -5.285E-04 3.626E-05 -1.246E-06 1.990E-08 0 S7 0 9.346E-04 -4.242E-05 1.472E-06 -1.724E-08 0 S8 0 5.785E-04 -9.262E-05 5.697E-06 -1.095E-07 0 S9 0 3.133E-04 -1.829E-05 1.422E-06 -4.402E-08 0 S10 0 3.598E-03 -9.299E-05 8.759E-07 -6.954E-09 0 S11 0 2.670E-03 -8.591E-05 3.331E-06 -5.069E-08 0 S12 0 -3.841E-03 9.486E-05 1.400E-06 -6.173E-08 0 S13 0 -6.006E-03 2.596E-04 -1.291E-05 5.749E-07 -1.218E-08 S14 0 3.540E-03 -2.430E-04 9.174E-06 -1.486E-07 0 S15 0 1.081E-03 1.118E-06 -2.125E-06 3.887E-08 0 S16 0 -1.767E-03 6.383E-05 -2.161E-06 2.699E-08 0 S17 0 -1.276E-03 5.163E-05 -1.412E-06 1.245E-08 0

[0131] Will refer to Figure 5 An imaging lens system according to a second embodiment is described.

[0132] The imaging lens system 200 may include a first lens 210 , a second lens 220 , a third lens 230 , a fourth lens 240 , a fifth lens 250 , a sixth lens 260 , a seventh lens 270 , and an eighth lens 280 .

[0133] The first lens 210 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The second lens 220 may have positive refractive power and may have a concave object-side surface and a convex image-side surface. 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 negative refractive power and may have a concave object-side surface and a concave image-side surface. The fifth lens 250 may have positive refractive power and may have a convex object-side surface and a convex 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. The seventh lens 270 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The eighth lens 280 may have positive refractive power and may have a convex object-side surface and a concave image-side surface.

[0134] The imaging lens system 200 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the second lens 220 and the third lens 230. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 280 and the imaging surface IP.

[0135] Figure 6 shows aberration curves of the imaging lens system according to the present embodiment, and Figure 7 and Figure 8 The MTF characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0136] Tables 3 and 4 show lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0137] Table 3

[0138] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens -109.253 0.800 1.7725 49.62 3.6 8.0 S2 4.894 2.583 S3 Second lens -68.628 2.921 1.6561 21.24 -120.0 66.0 S4 -12.716 0.155 S5 Aperture infinity 1.328 - - - - S6 The third lens 17.619 2.993 1.7433 49.34 5.8 6.0 S7 -8.464 0.769 S8 The fourth lens -19.600 1.000 1.6561 21.24 -120.0 66.0 S9 12.157 0.185 S10 Fifth lens 92.809 3.000 1.5365 56.5 -95.7 60.0 S11 -7.336 0.755 S12 The sixth lens 9.965 1.617 1.6561 21.24 -120.0 66.0 S13 5.261 0.927 S14 Seventh lens 62.293 2.368 1.5365 56.5 -95.7 60.0 S15 -20.877 0.100 S16 The eighth lens 9.604 2.495 1.5909 67.17 -2.0 9.7 S17 20.323 4.674 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 2.900 S20 infinity -2.886 - - - - S21 Imaging surface infinity 0.000 - - - -

[0139] Table 4

[0140]

[0141]

[0142] Will refer to Fig. 9 An imaging lens system according to a third embodiment is described.

[0143] The imaging lens system 300 may include a first lens 310 , a second lens 320 , a third lens 330 , a fourth lens 340 , a fifth lens 350 , a sixth lens 360 , a seventh lens 370 , and an eighth lens 380 .

[0144] The first lens 310 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The second lens 320 may have positive refractive power and may have a concave object-side surface and a convex image-side surface. 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 negative refractive power and may have a concave object-side surface and a concave image-side surface. The fifth lens 350 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The sixth lens 360 may have negative refractive power and may have a convex object-side surface and a concave image-side surface. The seventh lens 370 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The eighth lens 380 may have positive refractive power and may have a convex object-side surface and a concave image-side surface.

[0145] 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 second lens 320 and the third lens 330. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 380 and the imaging surface IP.

[0146] Fig.10 shows aberration curves of the imaging lens system according to the present embodiment, and Fig.11 and Fig.12 The MTF characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0147] Table 5 and Table 6 show the lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0148] Table 5

[0149] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens -45.200 0.800 1.7725 49.62 3.6 8.0 S2 4.973 2.323 S3 Second lens -565.205 2.935 1.6561 21.24 -120.0 66.0 S4 -12.710 0.470 S5 Aperture infinity 1.635 - - - - S6 The third lens 16.930 2.923 1.7433 49.34 5.8 6.0 S7 -8.124 0.562 S8 The fourth lens -16.728 1.000 1.6561 21.24 -120.0 66.0 S9 12.645 0.179 S10 Fifth lens 122.119 3.000 1.5365 56.5 -95.7 60.0 S11 -7.341 0.890 S12 The sixth lens 9.090 1.739 1.6561 21.24 -120.0 66.0 S13 5.136 0.893 S14 Seventh lens 1504.231 2.006 1.5365 56.5 -95.7 60.0 S15 -16.697 0.233 S16 The eighth lens 17.577 3.000 1.5831 59.46 2.7 7.1 S17 232.471 1.399 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 2.900 S20 infinity 0.017 - - - - S21 Imaging surface infinity 0.000 - - - -

[0150] Table 6

[0151]

[0152]

[0153] Will refer to Fig.13 An imaging lens system according to a fourth embodiment is described.

[0154] The imaging lens system 400 may include a first lens 410 , a second lens 420 , a third lens 430 , a fourth lens 440 , a fifth lens 450 , a sixth lens 460 , a seventh lens 470 , and an eighth lens 480 .

[0155] The first lens 410 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The second lens 420 may have positive refractive power and may have a concave object-side surface and a convex image-side surface. The third lens 430 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The fourth lens 440 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The fifth lens 450 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The sixth lens 460 may have negative refractive power and may have a convex object-side surface and a concave image-side surface. The seventh lens 470 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The eighth lens 480 may have positive refractive power and may have a convex object-side surface and a concave image-side surface.

[0156] The imaging lens system 400 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the second lens 420 and the third lens 430. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 480 and the imaging surface IP.

[0157] Fig.14 shows aberration curves of the imaging lens system according to the present embodiment, and Fig.15 and Fig.16 The MTF characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0158] Tables 7 and 8 show lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0159] Table 7

[0160] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens -69.023 0.800 1.7725 49.62 3.6 8.0 S2 4.940 2.317 S3 Second lens -62.662 3.000 1.6561 21.24 -120.0 66.0 S4 -11.153 0.467 S5 Aperture infinity 1.406 - - - - S6 The third lens 16.856 3.000 1.7433 49.34 5.8 6.0 S7 -8.485 0.500 S8 The fourth lens -17.522 1.000 1.6561 21.24 -120.0 66.0 S9 12.334 0.194 S10 Fifth lens 149.612 3.000 1.5365 56.5 -95.7 60.0 S11 -7.309 0.826 S12 The sixth lens 9.610 1.652 1.6561 21.24 -120.0 66.0 S13 5.223 1.055 S14 Seventh lens 128.295 2.209 1.5365 56.5 -95.7 60.0 S15 -16.894 0.100 S16 The eighth lens 10.662 2.390 1.5909 67.17 -2.0 9.7 S17 22.894 1.876 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 2.900 S20 infinity 0.015 - - - - S21 Imaging surface infinity 0.000 - - - -

[0161] Table 8

[0162]

[0163]

[0164] Will refer to Fig.17 An imaging lens system according to a fifth embodiment is described.

[0165] The imaging lens system 500 may include a first lens 510 , a second lens 520 , a third lens 530 , a fourth lens 540 , a fifth lens 550 , a sixth lens 560 , a seventh lens 570 , and an eighth lens 580 .

[0166] The first lens 510 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The second lens 520 may have positive refractive power and may have a concave object-side surface and a convex image-side surface. The third lens 530 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The fourth lens 540 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The fifth lens 550 may have positive refractive power and may have a concave object-side surface and a convex image-side surface. The sixth lens 560 may have negative refractive power and may have a convex object-side surface and a concave image-side surface. The seventh lens 570 may have positive refractive power and may have a concave object-side surface and a convex image-side surface. The eighth lens 580 may have positive refractive power and may have a convex object-side surface and a concave image-side surface.

[0167] The imaging lens system 500 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the second lens 520 and the third lens 530. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 580 and the imaging surface IP.

[0168] Fig.18 shows aberration curves of the imaging lens system according to the present embodiment, and Fig.19 and Fig. 20 The MTF characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0169] Tables 9 and 10 show lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0170] Table 9

[0171] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens -33.572 0.800 1.7725 49.62 3.6 8.0 S2 5.154 2.162 S3 Second lens -198.199 3.000 1.6561 21.24 -120.0 66.0 S4 -11.675 0.776 S5 Aperture infinity 0.429 - - - - S6 The third lens 21.393 2.886 1.768 49.24 4.4 5.9 S7 -7.805 0.504 S8 The fourth lens -15.372 1.000 1.6561 21.24 -120.0 66.0 S9 15.516 0.222 S10 Fifth lens -53.027 3.000 1.5365 56.5 -95.7 60.0 S11 -6.590 0.263 S12 The sixth lens 11.770 2.227 1.6561 21.24 -120.0 66.0 S13 5.496 0.910 S14 Seventh lens -90.680 2.381 1.5365 56.5 -95.7 60.0 S15 -17.061 0.315 S16 The eighth lens 10.475 3.000 1.592 67.02 -2.0 8.0 S17 104.508 1.864 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 2.900 S20 infinity 0.016 - - - - S21 Imaging surface infinity 0.000 - - - -

[0172] Table 10

[0173]

[0174]

[0175] Will refer to Fig.21 An imaging lens system according to a sixth embodiment is described.

[0176] The imaging lens system 600 may include a first lens 610 , a second lens 620 , a third lens 630 , a fourth lens 640 , a fifth lens 650 , a sixth lens 660 , a seventh lens 670 , and an eighth lens 680 .

[0177] The first lens 610 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The second lens 620 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The third lens 630 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The fourth lens 640 may have negative refractive power and may have a concave object-side surface and a concave image-side surface. The fifth lens 650 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The sixth lens 660 may have negative refractive power and may have a convex object-side surface and a concave image-side surface. The seventh lens 670 may have positive refractive power and may have a convex object-side surface and a convex image-side surface. The eighth lens 680 may have positive refractive power and may have a convex object-side surface and a convex image-side surface.

[0178] The imaging lens system 600 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the second lens 620 and the third lens 630. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 680 and the imaging surface IP.

[0179] Fig. 22 shows aberration curves of the imaging lens system according to the present embodiment, and Fig.23 and Fig.24 The MTF characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0180] Table 11 and Table 12 show lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0181] Table 11

[0182] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens -539.097 0.800 1.7725 49.62 3.6 8.0 S2 4.396 1.986 S3 Second lens 36.297 2.837 1.8081 22.76 -3.7 9.6 S4 -42.663 0.955 S5 Aperture infinity -0.029 - - - - S6 The third lens 20.818 2.375 1.7725 49.5 4.4 8.0 S7 -7.967 1.236 S8 The fourth lens -14.426 1.000 1.6198 25.31 -124.0 59.0 S9 9.713 0.314 S10 Fifth lens 120.753 2.883 1.5365 56.5 -95.7 60.0 S11 -4.874 0.100 S12 The sixth lens 12.106 1.855 1.6198 25.31 -124.0 59.0 S13 5.420 0.298 S14 Seventh lens 32.008 2.822 1.5365 56.5 -95.7 60.0 S15 -12.093 0.386 S16 The eighth lens 46.595 1.670 1.592 67.02 -2.0 8.0 S17 -200.000 2.924 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 2.900 S20 infinity 0.013 - - - - S21 Imaging surface infinity 0.000 - - - -

[0183] Table 12

[0184]

[0185]

[0186] Will refer to Fig.25 An imaging lens system according to a seventh embodiment is described.

[0187] The imaging lens system 700 may include a first lens 710 , a second lens 720 , a third lens 730 , a fourth lens 740 , a fifth lens 750 , a sixth lens 760 , a seventh lens 770 , and an eighth lens 780 .

[0188] The first lens 710 may have negative refractive power and may have a convex object side surface and a concave image side surface. The second lens 720 may have positive refractive power and may have a convex object side surface and a convex image side surface. The third lens 730 may have positive refractive power and may have a convex object side surface and a convex image side surface. The fourth lens 740 may have negative refractive power and may have a concave object side surface and a concave image side surface. The fifth lens 750 may have positive refractive power and may have a convex object side surface and a convex image side surface. The sixth lens 760 may have negative refractive power and may have a convex object side surface and a concave image side surface. The seventh lens 770 may have positive refractive power and may have a convex object side surface and a convex image side surface. The eighth lens 780 may have positive refractive power and may have a convex object side surface and a convex image side surface.

[0189] The imaging lens system 700 may further include a stop ST, a filter IF, and an imaging surface IP. The stop ST may be disposed between the second lens 720 and the third lens 730. The imaging surface IP may be formed on the image sensor IS, and the filter IF may be disposed between the eighth lens 780 and the imaging surface IP.

[0190] Fig.26 shows aberration curves of the imaging lens system according to the present embodiment, and Fig. 27 and Fig.28 The MTF characteristics and the amount of change in back focus according to temperature (ΔBFL: μm) in the imaging lens system according to the present embodiment are shown.

[0191] Tables 13 and 14 show lens characteristics and aspherical surface values ​​of the imaging lens system according to the present embodiment.

[0192] Table 13

[0193] Face number part Radius of curvature Thickness / distance Refractive Index Abbe number DT CTE S1 First lens 260.198 0.800 1.7725 49.62 3.6 8.0 S2 4.271 1.915 S3 Second lens 37.106 2.783 1.8081 22.76 -3.7 9.6 S4 -53.694 1.034 S5 Aperture infinity -0.207 - - - - S6 The third lens 17.104 2.061 1.7725 49.5 4.4 8.0 S7 -8.027 1.344 S8 The fourth lens -14.287 1.000 1.6198 25.31 -124.0 59.0 S9 9.339 0.354 S10 Fifth lens 161.819 3.000 1.5365 56.5 -95.7 60.0 S11 -4.844 0.100 S12 The sixth lens 11.506 1.928 1.6198 25.31 -124.0 59.0 S13 5.443 0.292 S14 Seventh lens 31.488 2.759 1.5365 56.5 -95.7 60.0 S15 -13.523 0.100 S16 The eighth lens 34.440 1.932 1.592 67.02 -2.0 8.0 S17 -200.000 2.666 S18 Optical Filters infinity 0.900 1.5168 64.17 1.6 8.0 S19 infinity 2.900 S20 infinity 0.014 - - - - S21 Imaging surface infinity 0.000 - - - -

[0194] Table 14

[0195]

[0196]

[0197] Tables 15 to 18 show optical characteristic values ​​and conditional expression values ​​of the imaging lens systems according to the first to seventh embodiments.

[0198] Table 15

[0199]

[0200] Table 16

[0201]

[0202]

[0203] Table 17

[0204]

[0205] Table 18

[0206]

[0207] Will refer to Fig.29 A camera module according to one or more embodiments is described.

[0208] The camera module 10 according to one or more embodiments of the present disclosure may include a lens barrel 20, a housing 30, and an image sensor IS. In addition, the camera module 10 may include an imaging lens system. For example, the camera module 10 according to one or more embodiments may include one of the imaging lens systems 100, 200, 300, 400, 500, 600, and 700 according to the first to seventh embodiments. For example, the first to eighth lenses of the imaging lens system may be sequentially accommodated inside the lens barrel 20. The housing 30 may be configured to accommodate the lens barrel 20 and the image sensor IS.

[0209] The lens barrel 20 and the housing 30 may be coupled by a coupling means such as an adhesive. The coupling point CP of the lens barrel 20 and the housing 30 may be positioned closer to the object side than the image side of the last lens 180, 280, 380, 480, 580, 680, and 780 of the imaging lens system. For example, the distance from the image side of the last lens 180, 280, 380, 480, 580, 680, and 780 of the imaging lens system to the coupling point CP of the lens barrel 20 and the housing 30 may be greater than 0.

[0210] The camera module 10 according to one or more embodiments of the present disclosure may satisfy one or more of the following conditional expressions:

[0211] 0.60 <BFL / CP<0.82

[0212] 0.80 <f3 / CP<1.0

[0213] In the conditional expression, BFL is the distance from the image side surface of the last lens 180, 280, 380, 480, 580, 680 and 780 of the imaging lens systems 100, 200, 300, 400, 500, 600 and 700 housed in the lens barrel 20 to the imaging surface, and f3 is the focal length of the third lens 130, 230, 330, 430, 530, 630 and 730 of the imaging lens systems 100, 200, 300, 400, 500, 600 and 700.

[0214] The lens barrel 20 and the housing 30 may be formed of different materials. For example, the lens barrel 20 may be formed of a plastic material, and the housing 30 may be formed of a metal material. As another example, the lens barrel 20 may be formed of a 6×10 -5 / ℃, and the housing 30 may be formed of a material having a CTE of 2.3×10 -5 / ℃ CTE of the material is formed.

[0215] The camera module 10 configured as described above may minimize focal length variation due to temperature variation through the lens barrel 20 , the housing 30 , and the imaging lens systems 100 , 200 , 300 , 400 , 500 , 600 , 700 .

[0216] According to one or more aspects and embodiments disclosed herein, the imaging lens system can achieve constant optical characteristics (focal length) over a wide temperature range from a high temperature environment of 80° C. to a low temperature environment of −40° C.

[0217] 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, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in sequence from the object side, wherein the seventh lens has a convex image side, wherein the eighth lens has a positive refractive power, wherein the imaging lens system satisfies the following conditional expression: 1.10 < f3 / f < 1.40, where f is the focal length of the imaging lens system, and f3 is the focal length of the third lens, and where the imaging lens system has a total of eight lenses.

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

3. The imaging lens system according to claim 1, wherein: The second lens has a convex image side.

4. The imaging lens system according to claim 1, wherein: The third lens has a convex image side.

5. The imaging lens system according to claim 1, wherein: The fourth lens has a concave image side.

6. The imaging lens system according to claim 1, wherein: The fifth lens has a convex image side.

7. The imaging lens system according to claim 1, wherein: The sixth lens has a concave image side.

8. A camera module, comprising: A housing; A lens barrel disposed in the housing and accommodating the imaging lens system according to any one of claims 1 to 7; And An image sensor disposed in the housing at the imaging plane of the imaging lens system.

9. The camera module according to claim 8, wherein: The connection point of the lens barrel and the housing is closer to the object side than the image side of the eighth lens, and wherein the camera module satisfies one or more of the following conditional expressions: 0.60 < BFL / CP < 0.82, and 0.80 < f3 / CP < 1.0, where CP is the connection point of the lens barrel and the housing, and BFL is the distance from the image side of the eighth lens to the imaging plane.

10. An imaging lens system, comprising: A first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in sequence from the object side, wherein the imaging lens system satisfies the following conditional expression: 1.0 < (L1DTn + L4DTn) / (L5DTn + L8DTn) < 1.4, where L1DTn is the refractive index change rate of the first lens according to temperature change, L4DTn is the refractive index change rate of the fourth lens according to temperature change, L5DTn is the refractive index change rate of the fifth lens according to temperature change, and L8DTn is the refractive index change rate of the eighth lens according to temperature change, and where the imaging lens system has a total of eight lenses.

11. The imaging lens system according to claim 10, wherein: The first lens has a concave image side.

12. The imaging lens system according to claim 10, wherein: The second lens has a convex image side.

13. The imaging lens system according to claim 10, wherein: The third lens has a convex image side.

14. The imaging lens system according to claim 10, wherein: The fourth lens has a concave image side.

15. The imaging lens system according to claim 10, wherein: The fifth lens has a convex image side.

16. The imaging lens system according to claim 10, wherein: The sixth lens has a concave image side.

17. The imaging lens system according to claim 10, wherein: The seventh lens has a convex image side.

18. The imaging lens system according to claim 10, wherein: The imaging lens system satisfies the following conditional expression: 4.0(10 -6 / ℃)<|L3DTn|<8.0(10 -6 / ℃), where L3DTn is the refractive index change rate of the third lens according to temperature change.

19. A camera module, comprising: A housing; A lens barrel disposed in the housing and accommodating the imaging lens system according to any one of claims 10 to 18; And an image sensor, arranged in the housing at the imaging surface of the imaging lens system, The lens barrel has a first thermal expansion coefficient, and the housing has a second thermal expansion coefficient different from the first thermal expansion coefficient.

20. An imaging lens system comprising: A first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens are arranged in order from the object side, The seventh lens has a convex image side surface. Wherein, the eighth lens has positive refractive power, Wherein, the imaging lens system satisfies the following conditional expression: 4.0(10 -6 / ℃)<|L3DTn|<8.0(10 -6 / ℃), Wherein, L3DTn is the rate of change of the refractive index of the third lens according to temperature change, and The imaging lens system has eight lenses in total.

21. Camera module, including: case; a lens barrel disposed in the housing and accommodating the imaging lens system according to claim 20; as well as An image sensor is arranged in the housing at the imaging surface of the imaging lens system.

Images