Optical imaging system

Abstract

The present application relates to an optical imaging system, comprising: a first lens having a refractive power; a second lens having a refractive power; a third lens having a convex object side surface, and a cusp formed on an image side surface of the third lens; a fourth lens having a refractive power; a fifth lens having a convex object side surface; and a sixth lens having a refractive power, and a cusp formed on an image side surface of the sixth lens, wherein the first lens to the sixth lens are sequentially arranged from the object side.

Description

[0001] This application claims priority and benefit to Korean Patent Application No. 10-2017-0164905, filed on December 4, 2017, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0002] This disclosure relates to an optical imaging system comprising six lenses, such as a telescopic optical imaging system. Background Technology

[0003] Miniature camera components can be installed in mobile communication terminals. For example, miniature camera components can be installed in devices with a thin form factor, such as mobile phones or similar devices. Miniature camera components may include an optical imaging system comprising a small number of lenses that allow the device to maintain its thin form factor. For example, the optical imaging system of a miniature camera component may include four or fewer lenses. However, such an optical imaging system may have a high f-number or focal length ratio, making it potentially difficult to use in a miniature camera module with high performance. Summary of the Invention

[0004] This summary is provided to introduce, in a simplified form, the selected concepts that will be further described in the detailed embodiments below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to help determine the scope of the claimed subject matter.

[0005] In general, an optical imaging system includes: a first lens having refractive power; a second lens having refractive power; a third lens having a convex object-side surface and forming an inflection point on its image-side surface; a fourth lens having refractive power; a fifth lens having a convex object-side surface; and a sixth lens having refractive power and forming an inflection point on its image-side surface, wherein the first lens to the sixth lens are arranged sequentially from the object side.

[0006] An inflection point can be formed on the image-side surface of the first lens.

[0007] The sign of the refractive power of the second lens may be different from that of the first lens.

[0008] The image-side surface of the third lens may be concave.

[0009] The fourth lens may have negative refractive power.

[0010] The fifth lens may have negative refractive power.

[0011] The image-side surface of the fifth lens may be concave.

[0012] The sixth lens may have positive refractive power.

[0013] The image-side surface of the sixth lens may be concave.

[0014] The optical imaging system may include an aperture stop disposed between the first lens and the second lens.

[0015] In general, an optical imaging system includes: a first lens having refractive power and having an inflection point formed on its image-side surface; a second lens having refractive power; a third lens having refractive power; a fourth lens having refractive power; a fifth lens having a convex object-side surface; and a sixth lens having refractive power and having an inflection point formed on its image-side surface, wherein the first lens to the sixth lens are arranged sequentially from the object side.

[0016] The inflection point can be formed on the image-side surface of the third lens.

[0017] The f-number of the optical imaging system can be 2.0 or less.

[0018] The field of view (FOV) of the optical imaging system can be 80° or greater.

[0019] In the optical imaging system, TTL / f < 1.2, where TTL is the distance from the object surface of the first lens to the imaging surface, and f is the total focal length of the optical imaging system.

[0020] In the optical imaging system, f1 / f < 1.0, where f is the total focal length of the optical imaging system and f1 is the focal length of the first lens.

[0021] In general, an optical imaging system includes: a first lens having positive refractive power and a convex object-side surface; a second lens having negative refractive power and a convex object-side surface; a third lens having positive refractive power, a convex object-side surface, and an inflection point formed on an image-side surface; a fourth lens having negative refractive power and a concave image-side surface; a fifth lens having negative refractive power; and a sixth lens having positive refractive power and a concave image-side surface, wherein the first lens to the sixth lens are arranged sequentially from the object side.

[0022] The first lens may have a concave image-side surface.

[0023] The inflection point can be formed on the image-side surface of the first lens.

[0024] The fifth lens and / or the sixth lens may have inflection points on the image-side surface and the object-side surface.

[0025] Other features and aspects will be apparent from the following detailed description, drawings and claims. Attached Figure Description

[0026] The above and other aspects, features and advantages of this disclosure will become more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0027] Figure 1 This is a diagram illustrating a first example of an optical imaging system;

[0028] Figure 2 Showing the representation Figure 1 The graph shows the aberration curves of the optical imaging system shown.

[0029] Figure 3 This is a diagram illustrating a second example of an optical imaging system;

[0030] Figure 4 Showing the representation Figure 3 The graph shows the aberration curves of the optical imaging system shown.

[0031] Figure 5 A third example of an optical imaging system is shown;

[0032] Figure 6 Showing the representation Figure 5 The graph shows the aberration curves of the optical imaging system.

[0033] Throughout the accompanying drawings and detailed description, the same reference numerals denote the same elements. The drawings may not be drawn to scale, and for clarity, illustration, and convenience, the relative dimensions, scale, and depiction of elements in the drawings may be exaggerated. In the drawings, modifications to the shapes shown may be estimated, for example, due to manufacturing techniques and / or tolerances. Therefore, the examples described herein should not be construed as being limited to specific shapes in the areas shown herein; for example, the examples described herein include changes in shape due to manufacturing processes. 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 modifications, alterations, and equivalents of the methods, apparatus, and / or systems described herein will be apparent after understanding the disclosure of this application. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein, but rather includes changes that will be apparent after understanding the disclosure of this application, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of features well-known in the art may be omitted.

[0035] 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 feasible ways of implementing the methods, apparatus, and / or systems described herein that will be apparent upon understanding the disclosure of this application.

[0036] Throughout the specification, when an element such as a layer, region, or substrate is described as being "on" another element, "connected" to another element, or "bonded" to another element, it may be directly "on" another element, "connected" to another element, or "bonded" to another element, or there may be one or more other elements in between. In contrast, when an element is described as being "directly on" another element, "directly connected" to another element, or "directly bonded" to another element, there may be no other elements in between.

[0037] As used herein, the term “and / or” includes any one of the relevant listed items and any combination of any two or more.

[0038] Although terms such as “first,” “second,” and “third” may be used herein to describe different components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts should not be limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teachings of the examples described herein, the first component, assembly, region, layer, or part in the examples may also be referred to as the second component, assembly, region, layer, or part.

[0039] For ease of description, spatial relative terms such as “above,” “upper,” “below,” and “lower” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relative terms are intended to include not only the orientation depicted in the drawings but also different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “upper” relative to another element will subsequently be “below” or “lower” relative to said other element. Thus, the term “above” encompasses both “above” and “below” orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relative terms used herein will be interpreted accordingly.

[0040] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the presence of the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0041] Variations in the shapes shown in the figures can occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the figures, but include variations in shape that occur during the manufacturing process.

[0042] Additionally, in various examples, the first lens can refer to the lens closest to the object being imaged (or the subject), while the sixth lens can refer to the lens closest to the imaging plane (or image sensor). Furthermore, all of the lens's radius of curvature and thickness, total track length (TTL) metering, ImgHT (half the diagonal length of the imaging plane), and focal length can be expressed in millimeters (mm). Moreover, the lens thickness, the spacing between lenses, and the TTL metering can be distances calculated based on the lens's optical axis. When describing the shape of a lens, a description of a convex surface means that the optical axis portion of that surface is convex, and a description of a concave surface means that the optical axis portion of that surface is concave. Therefore, although a description may indicate that a surface of the lens is convex, the edge portion of said surface of the same lens may be concave. Similarly, although a description may indicate that a surface of the lens is concave, the edge portion of said surface of the same lens may be convex.

[0043] An optical imaging system may include six lenses. For example, an optical imaging system may include a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens arranged sequentially from the object side. The first through sixth lenses may be configured to have air gaps between each lens. For example, the image surface of one lens and the object surface of another lens may not be in contact with each other.

[0044] In the example, the first lens may have refractive power. For example, the first lens may have positive refractive power. One surface of the first lens may be convex. For example, the object-side surface of the first lens may be convex. Inflection points may be formed on the first lens. For example, one or more inflection points may be formed on the image-side surface of the first lens.

[0045] In the example, the first lens may have an aspherical surface. For example, both surfaces of the first lens may be aspherical. The first lens may be formed using a material with high light transmittance and excellent processability. For example, the first lens may be formed using plastic. However, the material of the first lens is not limited to plastic. For example, the first lens may be formed using glass. The first lens may have a low refractive index. For example, the refractive index of the first lens may be less than 1.6, but it is not limited thereto.

[0046] In the example, the second lens may have refractive power. For example, the second lens may have negative refractive power. One surface of the second lens may be convex. For example, the object surface of the second lens may be convex.

[0047] In the example, the second lens may have an aspherical surface. For example, the object-side surface of the second lens may be aspherical. The second lens may be formed using a material with high light transmittance and excellent processability. For example, the second lens may be formed using plastic. However, the material of the second lens is not limited to plastic. For example, the second lens may also be formed using glass. The refractive index of the second lens may be greater than that of the first lens. For example, the refractive index of the second lens may be 1.65 or greater, but is not limited thereto.

[0048] In the example, the third lens may have refractive power. For example, the third lens may have positive refractive power. One surface of the third lens may be convex. For example, the object-side surface of the third lens may be convex. Inflection points may be formed on the third lens. For example, one or more inflection points may be formed on the image-side surface of the third lens.

[0049] In the example, the third lens may have an aspherical surface. For example, both surfaces of the third lens may be aspherical. The third lens may be formed using a material with high light transmittance and excellent processability. For example, the third lens may be formed using plastic. However, the material of the third lens is not limited to plastic. For example, the third lens may be formed using glass. The refractive index of the third lens may be less than the refractive index of the second lens. For example, the refractive index of the third lens may be less than 1.6, but it is not limited thereto.

[0050] In the example, the fourth lens may have refractive power. For example, the fourth lens may have negative refractive power. One surface of the fourth lens may be concave. For example, the image-side surface of the fourth lens may be concave.

[0051] In the example, the fourth lens may have an aspherical surface. For example, the object-side surface of the fourth lens may be spherical, and its image-side surface may be aspherical. The fourth lens may be formed using a material with high light transmittance and excellent processability. For example, the fourth lens may be formed using plastic. However, the material of the fourth lens is not limited to plastic. For example, the fourth lens may be formed using glass. The refractive index of the fourth lens may be greater than that of the third lens. For example, the refractive index of the fourth lens may be 1.6 or greater, but is not limited to this.

[0052] In the example, the fifth lens may have refractive power. For example, the fifth lens may have negative refractive power. One surface of the fifth lens may be convex. For example, the object-side surface of the fifth lens may be convex. The fifth lens may have an inflection point. For example, an inflection point may be formed on at least one of the object-side surface and the image-side surface of the fifth lens.

[0053] In the example, the fifth lens may have an aspherical surface. For example, both surfaces of the fifth lens may be aspherical. The fifth lens may be formed using a material with high light transmittance and excellent processability. For example, the fifth lens may be formed using plastic. However, the material of the fifth lens is not limited to plastic. For example, the fifth lens may be formed using glass. The fifth lens may have a refractive index substantially similar to that of the fourth lens. For example, the refractive index of the fifth lens may be 1.6 or greater, but is not limited to this.

[0054] In the example, the sixth lens may have refractive power. For example, the sixth lens may have positive refractive power. One surface of the sixth lens may be concave. For example, the image-side surface of the sixth lens may be concave. The sixth lens may have an inflection point. For example, an inflection point may be formed on at least one of the object-side surface and the image-side surface of the sixth lens.

[0055] In the example, the sixth lens may have an aspherical surface. For example, both surfaces of the sixth lens may be aspherical. The sixth lens may be formed using a material with high light transmittance and excellent processability. For example, the sixth lens may be formed using plastic. However, the material of the sixth lens is not limited to plastic. For example, the sixth lens may be formed using glass. The refractive index of the sixth lens may be less than that of the fifth lens. For example, the refractive index of the sixth lens may be less than 1.6, but it is not limited to this.

[0056] The aspherical surfaces of the first to sixth lenses can be represented by the following Equation 1:

[0057] [Equation 1]

[0058]

[0059] Here, c is the reciprocal of the radius of curvature of the lens, k is the conic constant, r is the distance from a point on the aspherical surface of the lens to the optical axis, A to H are the aspherical coefficients, and Z (or SAG) is the distance between a point on the aspherical surface of the lens at a distance r from the optical axis and a tangent plane intersecting the vertex of the aspherical surface of the lens.

[0060] Optical imaging systems may also include filters, image sensors, and apertures.

[0061] A filter can be placed between the sixth lens and the image sensor. The filter blocks certain wavelengths of light. For example, a filter can block infrared wavelengths of light.

[0062] Image sensors can form an imaging surface. For example, the surface of an image sensor can form an imaging surface.

[0063] An aperture stop can be set to control the amount of light incident on the lens. For example, the aperture stop can be set between the first lens and the second lens.

[0064] An optical imaging system can satisfy the following conditional expression:

[0065] Conditional expression 1: F No. ≤ 2.0

[0066] Conditional expression 2 80°≤FOV

[0067] Conditional expression 3: TTL / f < 1.2

[0068] Conditional expression 4: f1 / f < 1.0

[0069] Conditional expression 5 4.0 <D34 / D12

[0070] Conditional expression 6 1.0 <D34 / D23

[0071] Conditional expression 7 0.8 <D34 / D45<1.0

[0072] Conditional expression 8 6.0<|R7 / R8|

[0073] Conditional expression 9 20 <f6 / f1

[0074] Conditional expression 10 6 <f3 / f1

[0075] Conditional expression 11 -3.0 <f3 / f4<-1.0

[0076] Here, F No. is the f-number of the optical imaging system, TTL is the distance from the object surface of the first lens to the image surface, f is the total focal length of the optical imaging system, D12 is the distance from the image surface of the first lens to the object surface of the second lens, D23 is the distance from the image surface of the second lens to the object surface of the third lens, D34 is the distance from the image surface of the third lens to the object surface of the fourth lens, D45 is the distance from the image surface of the fourth lens to the object surface of the fifth lens, R7 is the radius of curvature of the object surface of the fourth lens, R8 is the radius of curvature of the image surface of the fourth lens, f1 is the focal length of the first lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, and f6 is the focal length of the sixth lens.

[0077] Next, optical imaging systems based on various examples will be described.

[0078] Reference Figure 1 An example describing an optical imaging system.

[0079] The optical imaging system 100 according to the example may include a first lens 110, a second lens 120, a third lens 130, a fourth lens 140, a fifth lens 150, and a sixth lens 160.

[0080] The first lens 110 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on the image-side surface of the first lens 110. The second lens 120 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. The third lens 130 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on the image-side surface of the third lens 130. The fourth lens 140 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. The fifth lens 150 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on both surfaces of the fifth lens 150. The sixth lens 160 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on both surfaces of the sixth lens 160.

[0081] The optical imaging system 100 may also include a filter 170, an image sensor 180, and an aperture ST. The filter 170 may be disposed between the sixth lens 160 and the image sensor 180, and the aperture ST may be disposed between the first lens 110 and the second lens 120.

[0082] The optical imaging system configured as described above can exhibit the following characteristics: Figure 2The aberration characteristics are shown in Tables 1 and 2. The lens characteristics and aspherical values ​​of the example optical imaging system are represented by Tables 1 and 2.

[0083] [Table 1]

[0084]

[0085] [Table 2]

[0086] radius of curvature 1.437 6.025 32.940 5.556 6.339 11.458 188.589 13.962 12.914 5.816 1.652 1.448 k -0.328 0.979 -0.947 1.000 -1.000 0.000 0.953 13.443 2.121 -14.908 -2.928 -1.005 A 0.005 -0.047 -0.010 0.018 -0.101 -0.048 -0.104 -0.085 0.077 -0.087 -0.412 -0.321 B 0.008 -0.103 -0.059 0.115 0.322 -0.133 -0.207 -0.293 -0.359 0.011 0.242 0.179 C 0.039 0.420 0.488 -0.330 -2.074 0.589 0.588 0.796 0.431 0.019 -0.077 -0.076 D -0.236 -0.994 -1.140 0.997 6.309 -1.932 -0.573 -1.059 -0.32 -0.020 0.01 0.02 E 0.434 1.244 1.402 -1.581 -10.659 3.328 -0.556 0.762 0.126 0.008 -0.002 -0.004 F -0.377 -0.780 -0.793 1.199 9.231 -2.982 1.608 -0.276 -0.021 -0.002 0.000 0.000 G 0.114 0.193 0.172 -0.194 -3.033 1.152 -1.287 0.039 0.001 0.000 0.000 0.000 H 0 0 0 0 0 0 0.364 0 0 0 0 0.000

[0087] Reference Figure 3 A second example describing an optical imaging system.

[0088] In the second example, the optical imaging system 200 may include a first lens 210, a second lens 220, a third lens 230, a fourth lens 240, a fifth lens 250, and a sixth lens 260.

[0089] The first lens 210 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on the image-side surface of the first lens 210. The second lens 220 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. The third lens 230 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on the image-side surface of the third lens 230. The fourth lens 240 may have negative refractive power, and both its object-side and image-side surfaces may be concave. The fifth lens 250 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on both surfaces of the fifth lens 250. The sixth lens 260 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on both surfaces of the sixth lens 260.

[0090] The optical imaging system 200 may also include a filter 270, an image sensor 280, and an aperture ST. The filter 270 may be disposed between the sixth lens 260 and the image sensor 280, and the aperture ST may be disposed between the first lens 210 and the second lens 220.

[0091] The optical imaging system configured as described above can exhibit the following characteristics: Figure 4 The aberration characteristics are shown in Tables 3 and 4. The lens characteristics and aspherical values ​​of the optical imaging system according to the second example are represented by Tables 3 and 4.

[0092] [Table 3]

[0093]

[0094] [Table 4]

[0095] radius of curvature 1.440 6.025 31.322 5.610 6.304 11.416 -100.013 15.541 12.392 5.439 1.579 1.422 k -0.332 0.979 -0.947 1.000 -1.000 0.000 0.953 13.443 2.121 -14.908 -2.967 -1.009 A -0.002 -0.051 -0.006 0.018 -0.095 -0.052 -0.110 -0.086 0.084 -0.101 -0.429 -0.332 B 0.063 -0.082 -0.068 0.160 0.281 -0.083 -0.157 -0.271 -0.383 0.027 0.254 0.189 C -0.177 0.272 0.443 -0.629 -1.863 0.351 0.412 0.748 0.485 0.012 -0.081 -0.082 D 0.233 -0.546 -0.890 1.928 5.673 -1.336 -0.139 -1.007 -0.38 -0.019 0.02 0.02 E -0.129 0.586 0.925 -3.155 -9.587 2.496 -1.346 0.731 0.160 0.009 -0.002 -0.005 F -0.026 -0.293 -0.370 2.573 8.7297 -2.374 2.520 -0.266 -0.031 -0.002 0.000 0.001 G 0.026 0.048 0.027 -0.690 -2.718 0.970 -1.865 0.038 0.002 0.000 0.000 0.000 H 0 0 0 0 0 0 0.514 0 0 0 0 0.000

[0096] Reference Figure 5 A third example describing an optical imaging system.

[0097] In the example, the optical imaging system 300 may include a first lens 310, a second lens 320, a third lens 330, a fourth lens 340, a fifth lens 350, and a sixth lens 360.

[0098] In the example, the first lens 310 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on the image-side surface of the first lens 310. The second lens 320 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. The third lens 330 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on the image-side surface of the third lens 330. The fourth lens 340 may have negative refractive power, and its object-side surface may be concave, while its image-side surface may be concave. The fifth lens 350 may have negative refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on both surfaces of the fifth lens 350. The sixth lens 360 may have positive refractive power, and its object-side surface may be convex, while its image-side surface may be concave. An inflection point may be formed on both surfaces of the sixth lens 360.

[0099] The optical imaging system 300 may also include a filter 370, an image sensor 380, and an aperture ST. The filter 370 may be disposed between the sixth lens 360 and the image sensor 380, and the aperture ST may be disposed between the first lens 310 and the second lens 320.

[0100] The optical imaging system configured as described above can exhibit the following characteristics: Figure 6 The aberration characteristics are shown in Tables 5 and 6. The lens characteristics and aspherical values ​​of the optical imaging system according to the third example are represented by Tables 5 and 6.

[0101] [Table 5]

[0102]

[0103] [Table 6]

[0104] radius of curvature 1.447 6.250 31.516 5.538 6.270 10.925 -146.546 15.365 11.418 5.337 1.599 1.433 k -0.334 0.979 -0.947 1.000 -1.000 0.000 0.953 13.443 2.121 -14.908 -2.897 -1.007 A 0.004 -0.045 -0.007 0.023 -0.096 -0.052 -0.109 -0.088 0.084 -0.092 -0.424 -0.328 B 0.015 -0.164 -0.083 0.082 0.281 -0.103 -0.180 -0.274 -0.382 0.015 0.248 0.185 C 0.001 0.640 0.558 -0.117 -1.902 0.455 0.490 0.749 0.478 0.019 -0.077 -0.080 D -0.129 -1.340 -1.162 0.255 5.899 -1.604 -0.261 -0.997 -0.38 -0.022 0.01 0.02 E 0.276 1.515 1.240 -0.292 -10.097 2.896 -1.271 0.715 0.159 0.009 -0.002 -0.005 F -0.260 -0.869 -0.565 0.078 8.803 -2.703 2.562 -0.258 -0.032 -0.002 0.000 0.001 G 0.080 0.197 0.079 0.181 -2.899 1.086 -1.948 0.036 0.002 0.000 0.000 0.000 H 0 0 0 0 0 0 0.546 0 0 0 0 0.000

[0105] Table 7 shows examples of the values ​​of the conditional expressions for optical imaging systems.

[0106] [Table 7]

[0107]

[0108] As described in the examples above, an optical imaging system suitable for small camera components with high performance can be realized.

[0109] 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 should be considered descriptive only and not for limiting purposes. The description of features or aspects in each example will be considered applicable to similar features or aspects in other examples. Suitable results may be obtained if the described techniques are performed in a different order, and / or if components in the described system, architecture, apparatus, or circuit are combined in a different manner and / or replaced or supplemented by other components or their equivalents. Therefore, the scope of this disclosure is not limited by the specific embodiments but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents will be understood to be included in this disclosure.

Claims

1. An optical imaging system, comprising: The first lens has positive refractive power, a convex object surface, and a concave image surface; The second lens has negative refractive power, a convex object surface, and a concave image surface; The third lens has positive refractive power, a convex object surface and a concave image surface, and an inflection point is formed on the image surface; The fourth lens has negative refractive power and a concave image-side surface; The fifth lens has negative refractive power, a convex object surface, and a concave image surface; and The sixth lens has positive refractive power, a convex object surface and a concave image surface, and an inflection point is formed on the image surface. The optical imaging system comprises a total of six lenses with refractive power, arranged sequentially from the object side from the first lens to the sixth lens. Wherein, 0.8 < D34 / D45 < 1.0, where D34 is the distance from the image surface of the third lens to the object surface of the fourth lens, and D45 is the distance from the image surface of the fourth lens to the object surface of the fifth lens.

2. The optical imaging system of claim 1, wherein, The fourth lens has a convex object surface.

3. The optical imaging system of claim 1, wherein, The fourth lens has a concave object-side surface.

4. The optical imaging system of claim 1, wherein, 1.970≤F No.≤2.0, where F No. is the f-number of the optical imaging system.

5. The optical imaging system of claim 1, wherein, 6.0 < |R7 / R8| ≤ 13.507, where R7 is the radius of curvature of the object surface of the fourth lens and R8 is the radius of curvature of the image surface of the fourth lens.

6. The optical imaging system of claim 1, wherein, 20 < f6 / f1≤404.11, where f1 is the focal length of the first lens and f6 is the focal length of the sixth lens.

7. An optical imaging system, comprising: The first lens has positive refractive power, a convex object surface and a concave image surface, and an inflection point is formed on the image surface; The second lens has negative refractive power, a convex object surface, and a concave image surface; The third lens has positive refractive power, a convex object surface, and a concave image surface; The fourth lens has negative refractive power and a concave image-side surface; The fifth lens has negative refractive power, a convex object surface, and a concave image surface; and The sixth lens has positive refractive power, a convex object surface and a concave image surface, and an inflection point is formed on the image surface. The optical imaging system comprises a total of six lenses with refractive power, arranged sequentially from the object side from the first lens to the sixth lens. Wherein, 80°≤FOV≤83.25°, and FOV is the field of view of the optical imaging system, and Wherein, 0.8 < D34 / D45 < 1.0, where D34 is the distance from the image surface of the third lens to the object surface of the fourth lens, and D45 is the distance from the image surface of the fourth lens to the object surface of the fifth lens.

8. The optical imaging system of claim 7, wherein, 1.0 < D34 / D23≤1.546, where D23 is the distance from the image surface of the second lens to the object surface of the third lens.

9. The optical imaging system of claim 7, wherein, 6.0 < |R7 / R8|≤13.507, where R7 is the radius of curvature of the object surface of the fourth lens and R8 is the radius of curvature of the image surface of the fourth lens.

10. The optical imaging system of claim 7, wherein, 20 < f6 / f1≤404.11, where f1 is the focal length of the first lens and f6 is the focal length of the sixth lens.

Images