Optical image capturing system

Abstract

An optical imaging system is provided. The optical imaging system includes a first lens, a second lens, a third lens, a fourth lens having a positive refractive power, a fifth lens, a sixth lens, a seventh lens having a positive refractive power, an eighth lens, and a ninth lens, where the first to ninth lenses are disposed in order from an object side, and where the conditional expression 1.0 lt; f number lt; 1.4 and 1.30 < = TTL / flt; tTL is a distance on the optical axis from the object-side surface to the image-side surface of the first lens, and f is a focal length of the optical imaging system.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority of Korean Patent Application No. 10 - 2024 - 0039671, filed on March 22, 2024 with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical field

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

[0004] Optical systems capable of outputting bright images have been implemented in mobile devices. The brightness of an image can be related to the F - number of the optical system, and the smaller the F - number, the brighter the presented image. To reduce the F - number, the size of the entrance pupil can be increased, but as the size of the entrance pupil increases, aberration may occur. Summary of the utility model

[0005] The provision of this Summary of the utility model section aims to introduce, in a brief form, a selection of concepts, which will be further described in the Detailed implementation section below. This Summary of the utility model section is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to assist in determining the scope of the claimed subject matter.

[0006] In general, an optical imaging system includes a first lens, a second lens, a third lens, a fourth lens having a positive refractive power, a fifth lens, a sixth lens, a seventh lens having a positive refractive power, an eighth lens, and a ninth lens, wherein the first lens to the ninth lens are sequentially arranged from the object side, and wherein the condition expressions 1.0 < F - number < 1.4 and 1.30 ≤ TTL / f < 1.40 are satisfied, where TTL is the distance on the optical axis from the object surface of the first lens to the image plane, and f is the focal length of the optical imaging system.

[0007] Both the image surface of the third lens and the object surface of the fourth lens can be concave.

[0008] The fifth lens can have a concave object surface.

[0009] The sixth lens can have a concave image surface.

[0010] The seventh lens and the eighth lens can include an inflection point on at least one of the object surface and the image surface.

[0011] The eighth lens can have a convex image surface.

[0012] The first lens to the ninth lens can include three or more lenses having a refractive index equal to or greater than 1.60.

[0013] The condition expression 0.70 ≤ TTL / (2×IMG HT) < 0.80 can be satisfied, where IMG HT is half of the diagonal length of the image plane.

[0014] Generally speaking, the optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens arranged in sequence from the object side, where the seventh lens has a positive refractive power, and where the eighth lens has a convex image side surface.

[0015] The second lens, the third lens, and the sixth lens may have a refractive index equal to or greater than 1.60.

[0016] The seventh lens and the eighth lens may include an inflection point on at least one of the object side surface and the image side surface.

[0017] The fourth lens and the fifth lens may have a positive refractive power.

[0018] The condition expression 1.0 < F-number < 1.4 can be satisfied.

[0019] The sixth lens may have a negative refractive power and a concave image side surface.

[0020] The third lens may have a positive refractive power.

[0021] The sixth lens may have a convex object side surface.

[0022] The condition expression 1.30 ≤ TTL / f < 1.40 can be satisfied, where TTL is the distance on the optical axis from the object side surface of the first lens to the image plane, and f is the focal length of the optical imaging system.

[0023] The condition expression 0.70 ≤ TTL / (2×IMG HT) < 0.80 can be satisfied, where TTL is the distance on the optical axis from the object side surface of the first lens to the image plane, and 2×IMG HT is the diagonal length of the image plane.

[0024] Other features and aspects will be apparent from the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a configuration diagram showing an exemplary optical imaging system according to a first embodiment.

[0026] Figure 2 is a graph showing the aberration characteristics of an exemplary optical imaging system according to a first embodiment.

[0027] Figure 3 is a configuration diagram showing an exemplary optical imaging system according to a second embodiment.

[0028] Figure 4 This is a graph illustrating the aberration characteristics of an exemplary optical imaging system according to the second embodiment.

[0029] Figure 5 This is a configuration diagram illustrating an exemplary optical imaging system according to a third embodiment.

[0030] Figure 6 This is a graph illustrating the aberration characteristics of an exemplary optical imaging system according to a third embodiment.

[0031] Figure 7 This is a configuration diagram illustrating an exemplary optical imaging system according to a fourth embodiment.

[0032] Figure 8 This is a graph illustrating the aberration characteristics of an exemplary optical imaging system according to the fourth embodiment.

[0033] Throughout the accompanying drawings and detailed embodiments, the same reference numerals refer to the same elements unless otherwise described. For purposes of clarity, illustration, and convenience, the drawings may not be drawn to scale, and the relative dimensions, scale, and descriptions of elements in the drawings may be exaggerated. Detailed Implementation

[0034] The following detailed embodiments are provided to help the reader gain a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will become apparent upon understanding the disclosure of this application. For example, the order of operations described herein and / or the sequence of operations described herein are merely examples and are not limited to the order set forth herein, except for the order of operations and / or the order of operations which must occur in a specific sequence, but can be changed, as will become apparent upon understanding the disclosure of this application. As another example, the order of operations and / or the order of operations can be performed in parallel, except for the order of operations and / or at least a portion of the order of operations which must occur in a sequence (e.g., a specific sequence). Furthermore, for clarity and conciseness, descriptions of features known upon understanding the disclosure of this application may be omitted.

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

[0036] Throughout this specification, when a component, element, or layer is described as "on another component, element, or layer," "connected to," "attached to," or "joined to" another component, element, or layer, it may be directly "on another component, element, or layer," directly "connected to," "attached to," or "joined to" another component, element, or layer (e.g., in contact with another component, element, or layer), or one or more other components, elements, or layers may reasonably be present between that component, element, or layer and that other component, element, or layer. When a component, element, or layer is described as "directly on another component, element, or layer," "directly connected to," "directly attached to," or "directly joined to" another component, element, or layer, then there are no other components, elements, or layers between that component, element, or layer and that other component, element, or layer. Similarly, expressions such as "between" and "directly between," and "adjacent" and "directly adjacent" may also be interpreted as described above.

[0037] The terminology used herein is for describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the terms “a,” “an,” and “the” are intended to equally include the plural forms. As non-limiting examples, the terms “comprising,” “including,” and “having” indicate the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not preclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof, or alternatives to the stated features, quantities, operations, components, elements, and / or combinations thereof. Furthermore, while one embodiment may describe the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof using the terms “comprising,” “including,” and “having,” other embodiments may exist in which one or more of the stated features, quantities, operations, components, elements, and / or combinations thereof are absent.

[0038] As used herein, the term “and / or” includes any one of the associated listed items and any combination of any two or more items. Phrases such as “at least one of A, B, and C” are intended to have a disjunctive meaning, and these phrases also include examples in which one or more of A, B, and C may be present (e.g., any combination of one or more of A, B, and C), unless the corresponding description and implementation require that the enumeration (e.g., “at least one of A, B, and C”) be interpreted as having a conjunctive meaning.

[0039] The features described herein may be embodied in various 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 in which the methods, apparatus, and / or systems described herein will be apparent upon understanding the disclosure of this application. In this document, the use of the term “may” (e.g., regarding what an example or implementation may include or implement) with respect to an example or implementation means that there exists at least one example or implementation that includes or implements such a feature, and that all examples or implementations are not limited thereto. The terms “example” or “implementation” as used herein have the same meaning (e.g., the phrase “in one example” has the same meaning as “in one implementation,” and “in one or more examples” has the same meaning as “in one or more implementations”).

[0040] One or more examples can provide optical imaging systems with low F-numbers and thin thicknesses.

[0041] In one or more embodiments, the values ​​of radius of curvature, thickness, distance, focal length, IMG HT (half the diagonal length of the image plane), and lens half-aperture can be in millimeters (mm), and the field of view (FOV) can be in degrees (°). Additionally, the lens thickness and the distance between lenses can refer to thickness and distance along the optical axis.

[0042] In one or more embodiments, the object side may refer to the side on which the object is disposed, and the image side may refer to the side on which the image surface (i.e., the image sensor) on which the image is formed.

[0043] In the description relating to the shape of the lens in the embodiments, a convex surface may mean that the paraxial region (a narrow region near the optical axis) of the surface is convex, and a concave surface may mean that the paraxial region of the surface is concave. Therefore, even when one surface of the lens is described as having a convex shape, the edge portion of the lens may be concave. Similarly, although one surface of the lens is described as having a concave shape, the edge portion of the lens may be convex.

[0044] An optical imaging system according to one or more embodiments may be implemented in a camera of a mobile device. The mobile device may be any type of portable electronic device including, but not limited to, a smart phone.

[0045] According to one or more embodiments, the optical imaging system may include nine lenses. For example, the optical imaging system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens sequentially arranged from the object side. The first lens to the ninth lens may each be disposed at a certain distance from an adjacent lens.

[0046] According to one or more embodiments, the optical imaging system may include plastic lenses. For example, at least a part of the first lens to the ninth lens may be configured as a plastic material, and preferably, the first lens to the ninth lens may be configured as a plastic material.

[0047] According to one or more embodiments, the optical imaging system may include aspherical lenses. For example, at least one of the object side surface and the image side surface of the first lens to the ninth lens may be aspherical, and preferably, both the object side surface and the image side surface of the first lens to the ninth lens may be aspherical. The aspherical surface of the lens may be represented by Equation 1 below.

[0048] Equation 1:

[0049]

[0050] In Equation 1, c is the reciprocal of the radius of curvature of the lens, K is the conic constant, Y is the distance from an arbitrary point on the aspherical surface to the optical axis, A - H, J, and L - P are the aspherical constants from the 4th order to the 30th order in sequence, and Z is the distance from an arbitrary point on the aspherical surface to the vertex of the aspherical surface in the optical axis direction.

[0051] According to one or more embodiments, the optical imaging system may further include an infrared cut-off filter, an image sensor, and an aperture. In one or more embodiments, the infrared cut-off filter may be disposed between the ninth lens and the image sensor to block infrared light in the light incident on the image sensor through the ninth lens. Additionally, in one or more embodiments, the aperture may be disposed between the third lens and the fourth lens and may adjust the amount of light incident on the lens.

[0052] According to one or more embodiments, the optical imaging system may satisfy one or more of the following conditional expressions:

[0053] (1) 1.0 < F-number < 1.4

[0054] (2) 1.30 ≤ TTL / f < 1.40

[0055] (3) 0.70 ≤ TTL / (2×IMG HT) < 0.80

[0056] In the conditional expression, TTL is the distance from the object side of the first lens to the image plane on the optical axis, f is the focal length of the optical imaging system, and 2×IMG HT is the diagonal length of the image plane.

[0057] The conditional expression (1) can be related to the brightness characteristics of an optical imaging system according to one or more embodiments. An optical imaging system according to one or more embodiments can be realized as a bright optical system by satisfying the conditional expression (1).

[0058] Conditional expressions (2) and (3) may be related to the miniaturization and thinning of the optical imaging system according to one or more embodiments. In particular, the optical imaging system according to one or more embodiments may have a low F-number and may be miniaturized and thinned, which is relatively difficult.

[0059] An optical imaging system according to one or more embodiments may satisfy at least one of conditional expressions (2) and (3) while satisfying conditional expression (1).

[0060] In addition, an optical imaging system according to one or more embodiments can satisfy one or more of the following conditional expressions.

[0061] (4) 1.0 < f1 / f < 1.5

[0062] (5) -5 < f2 / f < -2

[0063] (6) 20 < |f3 / f|

[0064] (7) 1 < f4 / f < 5

[0065] (8) 6 < f5 / f < 12

[0066] (9) -5 < f6 / f < -2

[0067] (10) 6 < f7 / f

[0068] (11) 0 <f8 / f < 1.5

[0069] (12) -2 < f9 / f < 0

[0070] (13) BFL / f < 0.18

[0071] (14) 0.1 < F - number / IMG HT < 0.5

[0072] (15) 2 < T1 / T9 < 4

[0073] (16) 1.7 < TTL / ΣCT < 1.9

[0074] (17) 2.8 < TTL / ΣAT < 3.2

[0075] In the 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, 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, f8 is the focal length of the eighth lens, and f9 is the focal length of the ninth lens. In addition, BFL is the distance on the optical axis from the image side of the ninth lens to the image plane, T1 is the thickness of the first lens on the optical axis, T9 is the thickness of the ninth lens on the optical axis, ΣCT is the sum of the thicknesses of the first lens to the ninth lens on the optical axis, and ΣAT is the sum of the distances of the first lens to the ninth lens on the optical axis.

[0076] Hereinafter, an optical imaging system according to one or more embodiments may be described.

[0077] First Implementation Method

[0078] Figure 1 is a configuration diagram showing an exemplary optical imaging system according to the first embodiment. Figure 2 is a graph showing the aberration characteristics of an exemplary optical imaging system according to the first embodiment.

[0079] The optical imaging system 100 according to the first embodiment 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, an eighth lens 180, and a ninth lens 190.

[0080] The first lens 110 may have a positive refractive power, its object side may be convex, and its image side may be concave. The first lens 110 may have a refractive index of 1.55 or less, and its Abbe number may be 50 or greater. The first lens 110 may be formed of a plastic material. The two surfaces of the first lens 110 may be aspherical.

[0081] The second lens 120 may have negative refractive power, its object side may be convex, and its image side may be concave. The refractive index of the second lens 120 may be 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The second lens 120 may be formed of a plastic material. Both surfaces of the second lens 120 may be aspherical.

[0082] The third lens 130 may have positive refractive power, its object side may be convex, and its image side may be concave. The refractive index of the third lens 130 may be 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The third lens 130 may be formed of a plastic material. Both surfaces of the third lens 130 may be aspherical.

[0083] The fourth lens 140 may have positive refractive power, its object side may be concave, and its image side may be convex. The fourth lens 140 may have a refractive index of 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The fourth lens 140 may be formed of a plastic material. Both surfaces of the fourth lens 140 may be aspherical.

[0084] The fifth lens 150 may have positive refractive power, its object side may be concave, and its image side may be convex. The fifth lens 150 may have a refractive index of less than 1.6, and its Abbe number may be 50 or greater. The fifth lens 150 may be formed of a plastic material. Both surfaces of the fifth lens 150 may be aspherical.

[0085] The sixth lens 160 may have negative refractive power, its object side may be convex, and its image side may be concave. The refractive index of the sixth lens 160 may be 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The sixth lens 160 may be formed of plastic material. Both surfaces of the sixth lens 160 may be aspherical.

[0086] The seventh lens 170 may have positive refractive power, its object-side surface may be convex, and its image-side surface may be concave. The refractive index of the seventh lens 170 may be 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The seventh lens 170 may be formed of a plastic material. Both surfaces of the seventh lens 170 may be aspherical. The seventh lens 170 may include two or more inflection points on at least one of the object-side and image-side surfaces (and preferably on both).

[0087] The eighth lens 180 may have positive refractive power, and both its object-side and image-side surfaces may be convex. The eighth lens 180 may have a refractive index of 1.55 or lower and an Abbe number of 50 or greater. The eighth lens 180 may be formed of a plastic material. Both surfaces of the eighth lens 180 may be aspherical. The eighth lens 180 may include two or more inflection points on either the object-side or image-side surface (and preferably on the object-side surface).

[0088] The ninth lens 190 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The refractive index of the ninth lens 190 may be 1.55 or lower, and its Abbe number may be 50 or higher. The ninth lens 190 may be formed of a plastic material. Both surfaces of the ninth lens 190 may be aspherical.

[0089] The image sensor S can be disposed on the image side of the ninth lens 190, and the infrared cut-off filter F can be disposed between the ninth lens 190 and the image sensor S.

[0090] According to the first embodiment, the second lens 120, the third lens 130, and the sixth lens 160 can be configured as high-refractive-index lenses with a refractive index of 1.60 or greater. Therefore, the sweep angle can be reduced, thereby reducing flare.

[0091] Tables 1 and 2 below list the lens characteristics and aspherical values ​​of an exemplary optical imaging system 100 according to a first embodiment.

[0092] Table 1

[0093] surface radius of curvature Thickness / Distance Refractive index Abbe number Effective radius 1 3.5803 1.1158 1.546 55.99 2.414 2 21.4321 0.0829 2.338 3 8.5769 0.2500 1.689 18.15 2.271 4 5.3930 0.3728 2.142 5 21.5067 0.2501 1.689 18.15 2.109 6 (Aperture) 24.9633 0.4764 2.014 7 -59.7181 0.3765 1.571 37.40 2.033 8 -13.4432 0.0893 2.196 9 -12.4481 0.6837 1.546 55.99 2.263 10 -8.9727 0.1298 2.339 11 534.6378 0.2500 1.689 18.15 2.394 12 15.0624 0.5129 2.588 13 6.9149 0.5498 1.571 37.40 2.991 14 6.9876 0.3459 3.230 15 4.5879 0.8269 1.546 55.99 3.410 16 -7.1721 0.9677 3.694 17 -6.6181 0.5000 1.546 55.99 4.367 18 3.2704 0.2634 5.384 19 infinity 0.2100 1.519 64.20 5.866 20 infinity 0.6940 5.936 21 infinity 0.0060 6.339

[0094] Table 2

[0095]

[0096]

[0097] Second Implementation Method

[0098] Figure 3 This is a configuration diagram illustrating an exemplary optical imaging system according to a second embodiment. Figure 4 This is a graph illustrating the aberration characteristics of an exemplary optical imaging system according to the second embodiment.

[0099] The optical imaging system 200 according to the second embodiment 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, an eighth lens 280, and a ninth lens 290.

[0100] The first lens 210 may have positive refractive power, its object side may be convex, and its image side may be concave. The refractive index of the first lens 210 may be 1.55 or lower, and its Abbe number may be 50 or higher. The first lens 210 may be formed of a plastic material. Both surfaces of the first lens 210 may be aspherical.

[0101] The second lens 220 may have negative refractive power, its object side may be convex, and its image side may be concave. The second lens 220 may have a refractive index of 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The second lens 220 may be formed of a plastic material. Both surfaces of the second lens 220 may be aspherical.

[0102] The third lens 230 may have negative refractive power, its object side may be convex, and its image side may be concave. The third lens 230 may have a refractive index of 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The third lens 230 may be formed of a plastic material. Both surfaces of the third lens 230 may be aspherical.

[0103] The fourth lens 240 may have positive refractive power, its object side may be concave, and its image side may be convex. The fourth lens 240 may have a refractive index of 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The fourth lens 240 may be formed of a plastic material. Both surfaces of the fourth lens 240 may be aspherical.

[0104] The fifth lens 250 may have positive refractive power, its object side may be concave, and its image side may be convex. The fifth lens 250 may have a refractive index of less than 1.6, and its Abbe number may be 50 or greater. The fifth lens 250 may be formed of a plastic material. Both surfaces of the fifth lens 250 may be aspherical.

[0105] The sixth lens 260 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The refractive index of the sixth lens 260 may be 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The sixth lens 260 may be formed of a plastic material. Both surfaces of the sixth lens 260 may be aspherical.

[0106] The seventh lens 270 may have positive refractive power, its object-side surface may be convex, and its image-side surface may be concave. The refractive index of the seventh lens 270 may be 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The seventh lens 270 may be formed of a plastic material. Both surfaces of the seventh lens 270 may be aspherical. The seventh lens 270 may include two or more inflection points on at least one of the object-side and image-side surfaces (and preferably on both).

[0107] The eighth lens 280 may have positive refractive power, and both its object-side and image-side surfaces may be convex. The eighth lens 280 may have a refractive index of 1.55 or lower and an Abbe number of 50 or greater. The eighth lens 280 may be formed of a plastic material. Both surfaces of the eighth lens 280 may be aspherical. The eighth lens 280 may include two or more inflection points on either the object-side or image-side surface (and preferably on the object-side surface).

[0108] The ninth lens 290 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The ninth lens 290 may have a refractive index of 1.55 or lower and an Abbe number of 50 or greater. The ninth lens 290 may be formed of a plastic material. Both surfaces of the ninth lens 290 may be aspherical.

[0109] The image sensor S can be disposed on the image side of the ninth lens 290, and the infrared cut-off filter F can be disposed between the ninth lens 290 and the image sensor S.

[0110] According to the second embodiment, the second lens 220, the third lens 230, and the sixth lens 260 can be configured as high-refractive-index lenses with a refractive index of 1.60 or greater. Therefore, the sweep angle can be reduced, thereby reducing flare.

[0111] Tables 3 and 4 below list the lens characteristics and aspherical values ​​of the exemplary optical imaging system 200 according to the second embodiment.

[0112] Table 3

[0113]

[0114]

[0115] Table 4

[0116]

[0117]

[0118] Third Implementation Method

[0119] Figure 5 This is a configuration diagram illustrating an exemplary optical imaging system according to a third embodiment. Figure 6 This is a graph illustrating the aberration characteristics of an exemplary optical imaging system according to a third embodiment.

[0120] The optical imaging system 300 according to the third embodiment 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, an eighth lens 380, and a ninth lens 390.

[0121] The first lens 310 may have positive refractive power, its object side may be convex, and its image side may be concave. The first lens 310 may have a refractive index of 1.55 or lower, and its Abbe number may be 50 or greater. The first lens 310 may be formed of a plastic material. Both surfaces of the first lens 310 may be aspherical.

[0122] The second lens 320 may have negative refractive power, its object side may be convex, and its image side may be concave. The second lens 320 may have a refractive index of 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The second lens 320 may be formed of a plastic material. Both surfaces of the second lens 320 may be aspherical.

[0123] The third lens 330 may have negative refractive power, its object side may be convex, and its image side may be concave. The third lens 330 may have a refractive index of 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The third lens 330 may be formed of a plastic material. Both surfaces of the third lens 330 may be aspherical.

[0124] The fourth lens 340 may have positive refractive power, its object side may be concave, and its image side may be convex. The fourth lens 340 may have a refractive index of 1.55 or greater but less than 1.60, and its Abbe number may be 30 or greater but less than 50. The fourth lens 340 may be formed of a plastic material. Both surfaces of the fourth lens 340 may be aspherical.

[0125] The fifth lens 350 may have positive refractive power, its object side may be concave, and its image side may be convex. The fifth lens 350 may have a refractive index of less than 1.6, and its Abbe number may be 50 or greater. The fifth lens 350 may be formed of a plastic material. Both surfaces of the fifth lens 350 may be aspherical.

[0126] The sixth lens 360 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The refractive index of the sixth lens 360 may be 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The sixth lens 360 may be formed of a plastic material. Both surfaces of the sixth lens 360 may be aspherical.

[0127] The seventh lens 370 may have positive refractive power, its object-side surface may be convex, and its image-side surface may be concave. The refractive index of the seventh lens 370 may be 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The seventh lens 370 may be formed of a plastic material. Both surfaces of the seventh lens 370 may be aspherical. The seventh lens 370 may include two or more inflection points on at least one of the object-side and image-side surfaces (preferably on both surfaces).

[0128] The eighth lens 380 may have positive refractive power, and both its object-side and image-side surfaces may be convex. The eighth lens 380 may have a refractive index of 1.55 or lower and an Abbe number of 50 or greater. The eighth lens 380 may be formed of a plastic material. Both surfaces of the eighth lens 380 may be aspherical. The eighth lens 380 may include two or more inflection points on either the object-side or image-side surface (and preferably on the object-side surface).

[0129] The ninth lens 390 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The ninth lens 390 may have a refractive index of 1.55 or lower and an Abbe number of 50 or greater. The ninth lens 390 may be formed of a plastic material. Both surfaces of the ninth lens 390 may be aspherical.

[0130] The image sensor S can be disposed on the image side of the ninth lens 390, and the infrared cut-off filter F can be disposed between the ninth lens 390 and the image sensor S.

[0131] According to the third embodiment, the second lens 320, the third lens 330, and the sixth lens 360 can be configured as high-refractive-index lenses with a refractive index of 1.60 or greater. Therefore, the sweep angle can be reduced, thereby reducing flare.

[0132] Tables 5 and 6 below list the lens characteristics and aspherical values ​​of the optical imaging system 300 according to the third embodiment.

[0133] Table 5

[0134]

[0135]

[0136] Table 6

[0137]

[0138]

[0139] Fourth Implementation Method

[0140] Figure 7 This is a configuration diagram illustrating an exemplary optical imaging system according to a fourth embodiment. Figure 8 This is a graph illustrating the aberration characteristics of an exemplary optical imaging system according to the fourth embodiment.

[0141] The optical imaging system 400 according to the fourth embodiment 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, an eighth lens 480, and a ninth lens 490.

[0142] The first lens 410 may have positive refractive power, its object side may be convex, and its image side may be concave. The first lens 410 may have a refractive index of 1.55 or lower, and its Abbe number may be 50 or greater. The first lens 410 may be formed of a plastic material. Both surfaces of the first lens 410 may be aspherical.

[0143] The second lens 420 may have negative refractive power, its object side may be convex, and its image side may be concave. The second lens 420 may have a refractive index of 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The second lens 420 may be formed of a plastic material. Both surfaces of the second lens 420 may be aspherical.

[0144] The third lens 430 may have negative refractive power, its object side may be convex, and its image side may be concave. The third lens 430 may have a refractive index of 1.60 or greater, preferably 1.65 or greater, and its Abbe number may be less than 20. The third lens 430 may be formed of a plastic material. Both surfaces of the third lens 430 may be aspherical.

[0145] The fourth lens 440 may have positive refractive power, its object side may be concave, and its image side may be convex. The fourth lens 440 may have a refractive index of 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The fourth lens 440 may be formed of a plastic material. Both surfaces of the fourth lens 440 may be aspherical.

[0146] The fifth lens 450 may have positive refractive power, its object side may be concave, and its image side may be convex. The fifth lens 450 may have a refractive index of less than 1.6, and its Abbe number may be 50 or greater. The fifth lens 450 may be formed of a plastic material. Both surfaces of the fifth lens 450 may be aspherical.

[0147] The sixth lens 460 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The refractive index of the sixth lens 460 may be 1.60 or greater, and preferably 1.65 or greater, and its Abbe number may be less than 20. The sixth lens 460 may be formed of a plastic material. Both surfaces of the sixth lens 460 may be aspherical.

[0148] The seventh lens 470 may have positive refractive power, its object-side surface may be convex, and its image-side surface may be concave. The refractive index of the seventh lens 470 may be 1.55 or greater and less than 1.60, and its Abbe number may be 30 or greater and less than 50. The seventh lens 470 may be formed of a plastic material. Both surfaces of the seventh lens 470 may be aspherical. The seventh lens 470 may include two or more inflection points on at least one of the object-side and image-side surfaces (preferably on both surfaces).

[0149] The eighth lens 480 may have positive refractive power, and both its object-side and image-side surfaces may be convex. The eighth lens 480 may have a refractive index of 1.55 or greater and less than 1.60, and an Abbe number of 30 or greater and less than 50. The eighth lens 480 may be formed of a plastic material. Both surfaces of the eighth lens 480 may be aspherical. The eighth lens 480 may include two or more inflection points on either the object-side or image-side surface (and preferably on the object-side surface).

[0150] The ninth lens 490 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The refractive index of the ninth lens 490 may be 1.55 or lower, and its Abbe number may be 50 or higher. The ninth lens 490 may be formed of a plastic material. Both surfaces of the ninth lens 490 may be aspherical.

[0151] The image sensor S can be disposed on the image side of the ninth lens 490, and the infrared cut-off filter F can be disposed between the ninth lens 490 and the image sensor S.

[0152] According to the fourth embodiment, the second lens 420, the third lens 430, and the sixth lens 460 can be configured as high-refractive-index lenses with a refractive index of 1.60 or greater. Therefore, the sweep angle can be reduced, thereby reducing flare.

[0153] Tables 7 and 8 below list the lens characteristics and aspherical values ​​of the optical imaging system 400 according to the fourth embodiment.

[0154] Table 7

[0155]

[0156]

[0157] Table 8

[0158]

[0159]

[0160] Table 9 below lists the optical and physical parameters of the optical imaging systems according to the first to fourth embodiments.

[0161] Table 9

[0162] First Implementation Method Second Implementation Method Third Implementation Method Fourth Implementation Method f 6.6073 6.5641 6.6868 6.6134 f1 7.6977 7.4393 7.2890 7.3179 f2 -21.7784 -21.3072 -19.4014 -19.6236 f3 218.9187 -193.0388 -1456.9921 -1600.4698 f4 30.3069 24.7243 27.2156 27.2182 f5 55.0025 68.8522 75.2340 75.2795 f6 -22.4946 -21.4344 -19.5103 -19.5843 f7 310.7942 70.3422 49.7154 50.1928 f8 5.2520 5.8923 5.8753 5.8833 f9 -3.9360 -4.3290 -4.2391 -4.3320 TTL 8.9538 8.8426 8.9660 8.9430 BFL 1.173 1.149 1.139 1.129 F-number 1.3735 1.3658 1.2868 1.2781 FOV 86.92 86.63 81.93 80.42 IMG HT 6.329 6.329 5.920 5.920 T1 1.1158 1.1105 1.3267 1.3386 T9 0.5000 0.5000 0.5000 0.5001 ΣCT 4.8028 4.6691 4.8459 4.8455 ΣAT 2.9777 3.0245 2.9814 2.9693

[0163] According to the above embodiments, the optical imaging system can obtain high-quality and bright images and can be manufactured in a small size, so that the optical imaging system can be used in mobile devices with limited space.

[0164] While this disclosure includes specific examples, it will be apparent upon understanding the disclosure of this application 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 to be understood in a descriptive sense only and not for purposes of limitation. The description of features or aspects in each example should be considered applicable to similar features or aspects in other examples. Appropriate results may still be achieved if the described techniques are performed in a different order, and / or if components in the described system, architecture, device, or circuit are combined in a different manner and / or replaced or supplemented by other components or their equivalents.

[0165] Therefore, in addition to the above disclosure and all the accompanying drawings, the scope of this disclosure also includes the claims and their equivalents, that is, all variations within the scope of the claims and their equivalents should be understood to be included in this disclosure.

Claims

1. An optical imaging system, characterized in that, The optical imaging system includes: A first lens, a second lens, a third lens, a fourth lens with positive refractive power, a fifth lens, a sixth lens, a seventh lens with positive refractive power, an eighth lens, and a ninth lens, wherein, the first lens to the ninth lens are arranged in sequence from the object side, and wherein, the condition expression 1.0 < F-number < 1.4 and 1.30 ≤ TTL / f < 1.40 are satisfied, wherein, TTL is the distance on the optical axis from the object side surface of the first lens to the image plane, and f is the focal length of the optical imaging system.

2. The optical imaging system according to claim 1, characterized in that, The image side surface of the third lens and the object side surface of the fourth lens are both concave.

3. The optical imaging system according to claim 1, characterized in that, The fifth lens has a concave object side surface.

4. The optical imaging system according to claim 1, characterized in that, The sixth lens has a concave image side surface.

5. The optical imaging system according to claim 1, characterized in that, The seventh lens and the eighth lens include an anastigmatic point on at least one of the object side surface and the image side surface.

6. The optical imaging system according to claim 1, characterized in that, The eighth lens has a convex image side surface.

7. The optical imaging system according to claim 1, characterized in that, The first lens to the ninth lens include three or more lenses having a refractive index equal to or greater than 1.

60.

8. The optical imaging system according to claim 1, characterized in that, The condition expression 0.70 ≤ TTL / (2×IMG HT) < 0.80 is satisfied, wherein, IMG HT is half of the diagonal length of the image plane.

9. An optical imaging system, characterized in that, The optical imaging system includes: A first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, and a ninth lens arranged in sequence from the object side, wherein, the seventh lens has positive refractive power, and wherein, the eighth lens has a convex image side surface.

10. The optical imaging system according to claim 9, characterized in that, The second lens, the third lens, and the sixth lens have a refractive index equal to or greater than 1.

60.

11. The optical imaging system according to claim 9, characterized in that, The seventh lens and the eighth lens include an anastigmatic point on at least one of the object side surface and the image side surface.

12. The optical imaging system according to claim 9, characterized in that, The fourth lens and the fifth lens have positive refractive power.

13. The optical imaging system according to claim 9, characterized in that, The condition expression 1.0 < F-number < 1.4 is satisfied.

14. The optical imaging system according to claim 9, characterized in that, The sixth lens has negative refractive power and a concave image side surface.

15. The optical imaging system according to claim 9, characterized in that, The third lens has positive refractive power.

16. The optical imaging system according to claim 9, characterized in that, The sixth lens has a convex object side surface.

17. The optical imaging system according to claim 9, characterized in that, The condition expression 1.30 ≤ TTL / f < 1.40 is satisfied, wherein, TTL is the distance on the optical axis from the object side surface of the first lens to the image plane, and f is the focal length of the optical imaging system.

18. The optical imaging system according to claim 9, characterized in that, The condition expression 0.70 ≤ TTL / (2×IMG HT) < 0.80 is satisfied, wherein, TTL is the distance on the optical axis from the object side surface of the first lens to the image plane, and 2×IMG HT is the diagonal length of the image plane.

Images