Wide-angle optical imaging lens

Abstract

The utility model relates to the technical field of optical lenses, in particular to a wide-angle optical imaging lens, which sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens from an object side to an image side along an optical axis, the second lens has negative focal power, the object side surface of the second lens is a convex surface, and the image side surface is a convex surface; the third lens has negative focal power, and the image side surface of the third lens is a concave surface; the fourth lens has focal power; the fifth lens has positive focal power; the sixth lens has positive focal power; the seventh lens has negative focal power; the first to seventh lenses are plastic aspheric lenses; the conditional expression is satisfied: 1.9111 lt; | (ImgH * tan (FOV)) / TTL | lt; 2.0467, 2.0467; wherein ImgH is half of the maximum image height; the FOV is the maximum field angle; tTL is the total optical length from the object side surface to the image surface of the first lens. Through the reasonable design of the first to seventh lenses, the lens meets the requirements of wide angle and high imaging quality.

Description

Technical Field

[0001] The utility model relates to the technical field of optical lenses, in particular to a wide-angle optical imaging lens. Background Art

[0002] In recent years, with the rise of portable electronic products with camera functions, the market has higher requirements for the imaging quality of electronic devices. When shooting, handheld optical imaging lenses have problems such as low light transmittance, small field of view, and low resolution, which are difficult to meet market demand. In order to meet the development trend of electronic devices gradually towards wide angle and high image quality, it is urgent to develop an optical imaging lens with both wide angle and high imaging quality. Utility Model Content

[0003] In view of the above-mentioned shortcomings and deficiencies of the prior art, the utility model provides a wide-angle optical imaging lens, which is mainly composed of seven lenses, and the seven lenses all adopt a plastic aspherical design. Through the reasonable design of the first lens to the seventh lens, the optical imaging lens meets the requirements of wide angle and high imaging quality.

[0004] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the utility model include:

[0005] A wide-angle optical imaging lens, which is composed of the following components from the object side to the image side along the optical axis:

[0006] The first lens has positive power; the object side surface of the first lens is concave at the near optical axis, and the image side surface is convex at the near optical axis;

[0007] The second lens has a negative optical power; the object side surface of the second lens is convex at the near optical axis, and the image side surface is convex at the near optical axis;

[0008] The third lens has negative power, and the image side surface of the third lens is concave at the near optical axis;

[0009] a fourth lens having optical power;

[0010] a fifth lens having positive refractive power;

[0011] a sixth lens having positive refractive power;

[0012] A seventh lens having negative optical power;

[0013] The first to seventh lenses are all plastic aspherical lenses;

[0014] The optical imaging lens satisfies the following conditional formula:

[0015] 1.9111<│(ImgH*tan(FOV)) / TTL│<2.0467

[0016] Wherein, ImgH is half of the maximum image height of the optical imaging lens; FOV is the maximum field of view of the optical imaging lens; TTL is the total optical length from the object side of the first lens to the image plane of the optical imaging lens.

[0017] By reasonably matching the optical power, surface shape and distribution parameters of each lens and satisfying the above-mentioned conditional formula, the optical imaging lens has a larger field of view, a smaller total optical length and high imaging quality.

[0018] Furthermore, the optical imaging lens satisfies the following conditional formula:

[0019] 1.99 <f / EPD<2.11

[0020] Wherein, f is the effective focal length of the optical imaging lens; EPD is the entrance pupil diameter of the optical imaging lens.

[0021] By controlling the ratio of the effective focal length to the entrance pupil diameter, the optical imaging lens can have a large aperture.

[0022] Furthermore, the optical imaging lens satisfies the following conditional formula:

[0023] 0.2 <f1 / R2<1.64

[0024] Among them, f1 is the focal length of the first lens in the optical imaging lens; R2 is the curvature radius of the image side surface of the first lens in the optical imaging lens.

[0025] By satisfying the above conditional expression, the processing difficulty of the first lens is effectively reduced.

[0026] Furthermore, the optical imaging lens satisfies the following conditional formula:

[0027] 1.82 <TTL / f<1.96

[0028] Wherein, f is the effective focal length of the optical imaging lens.

[0029] By adjusting the ratio of the total optical length to the effective focal length of the optical imaging lens, miniaturization can be achieved while allowing light to better converge on the image plane.

[0030] The beneficial effects of the utility model are:

[0031] The utility model provides a wide-angle optical imaging lens, which is mainly composed of seven lenses, and the seven lenses are all designed with plastic aspherical surfaces. Through the reasonable design of the surface shapes and focal lengths of the first lens to the seventh lens, and the reasonable distribution of the spacing and thickness of each lens, the optical imaging lens has both wide angle and high imaging quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0033] Figure 2 This is a distortion curve diagram of Example 1 of the utility model;

[0034] Figure 3 is an astigmatism curve diagram of Example 1 of the utility model;

[0035] Figure 4 This is a schematic diagram of the structure of Embodiment 2 of the present utility model;

[0036] Figure 5 This is a distortion curve diagram of Example 2 of the utility model;

[0037] Figure 6 is an astigmatism curve diagram of Example 2 of the utility model;

[0038] Figure 7 This is a schematic diagram of the structure of Embodiment 3 of the present utility model;

[0039] Figure 8 This is a distortion curve diagram of Example 3 of the utility model;

[0040] Fig. 9 is an astigmatism curve diagram of Example 3 of the utility model;

[0041] Fig.10 This is a schematic diagram of the structure of Embodiment 4 of the present utility model;

[0042] Fig.11 This is a distortion curve diagram of Example 4 of the utility model;

[0043] Fig.12 is an astigmatism curve diagram of Example 4 of the utility model;

[0044] Fig.13 This is a schematic diagram of the structure of Embodiment 5 of the present utility model;

[0045] Fig.14 This is a distortion curve diagram of Example 5 of the present utility model;

[0046] Fig.15 This is an astigmatism curve diagram of Example 5 of the utility model.

[0047] In the figure: 1, first lens; 2, second lens; 3, third lens; 4, fourth lens; 5, fifth lens; 6, sixth lens; 7, seventh lens; 8, aperture; 9, filter. DETAILED DESCRIPTION

[0048] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below through specific implementation modes in conjunction with the accompanying drawings.

[0049] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0050] In this document, the surface of each lens closest to the object is called the object-side surface, and the surface of each lens closest to the imaging plane is called the image-side surface.

[0051] The wide-angle optical imaging lens provided in the embodiment of the utility model is composed of the following components in sequence from the object side to the image side along the optical axis:

[0052] The first lens 1 has positive power; the object side surface of the first lens 1 is concave at the near optical axis, and the image side surface is convex at the near optical axis;

[0053] The second lens 2 has a negative optical power; the object side surface of the second lens 2 is convex at the near optical axis, and the image side surface is convex at the near optical axis;

[0054] The third lens 3 has negative optical power, and the image side surface of the third lens 3 is concave at the near optical axis;

[0055] The fourth lens 4 has optical power;

[0056] A fifth lens 5 having positive refractive power;

[0057] A sixth lens 6 having positive refractive power;

[0058] A seventh lens element 7 having negative optical power;

[0059] The first lens 1 to the seventh lens 7 are all plastic aspherical lenses;

[0060] The optical imaging lens satisfies the following conditional formula:

[0061] 1.9111<│(ImgH*tan(FOV)) / TTL│<2.0467

[0062] Wherein, ImgH is half of the maximum image height of the optical imaging lens; FOV is the maximum field of view of the optical imaging lens; and TTL is the total optical length from the object side to the image plane of the first lens 1 of the optical imaging lens.

[0063] By reasonably matching the optical power, surface shape and distribution parameters of each lens and satisfying the above-mentioned conditional formula, the optical imaging lens has a larger field of view, a smaller total optical length and high imaging quality.

[0064] Specifically, the optical imaging lens satisfies the following conditional formula:

[0065] 1.99 <f / EPD<2.11

[0066] Wherein, f is the effective focal length of the optical imaging lens; EPD is the entrance pupil diameter of the optical imaging lens.

[0067] By controlling the ratio of the effective focal length to the entrance pupil diameter, the optical imaging lens can have a large aperture.

[0068] Specifically, the optical imaging lens satisfies the following conditional formula:

[0069] 0.2 <f1 / R2<1.64

[0070] Wherein, f1 is the focal length of the first lens 1 in the optical imaging lens; R2 is the radius of curvature of the image side surface of the first lens 1 in the optical imaging lens.

[0071] By satisfying the above conditional expression, the difficulty of processing the first lens 1 is effectively reduced.

[0072] Specifically, the optical imaging lens satisfies the following conditional formula:

[0073] 1.82 <TTL / f<1.96

[0074] Wherein, f is the effective focal length of the optical imaging lens.

[0075] By adjusting the ratio of the total optical length to the effective focal length of the optical imaging lens, miniaturization can be achieved while allowing light to better converge on the image plane.

[0076] The above-mentioned lens may further include a filter 9 for correcting color deviation and / or a protective glass for protecting the photosensitive element located on the imaging surface according to the specific needs of the embodiment. In the absence of specific requirements, the filter 9 or the protective glass may not be used.

[0077] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0078] Example 1

[0079] The present embodiment provides a wide-angle optical imaging lens, which is composed of a first lens 1, an aperture 8, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7 and a filter 9 in sequence from the object side to the image side along the optical axis. Incident light passes through the above components in sequence and is finally imaged on the image plane. The first lens 1 has positive focal power, and its object side surface is concave at the near optical axis, and the image side surface is convex at the near optical axis. The second lens 2 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The third lens 3 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fourth lens 4 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fifth lens 5 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The sixth lens 6 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The seventh lens 7 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The filter 9 is arranged between the seventh lens 7 and the image plane.

[0080] Table 1 shows the surface type, radius of curvature, thickness and material properties of each lens in Example 1. The units of the radius of curvature and thickness are both millimeters (mm).

[0081] Table 1 is a table of lens parameters of Example 1.

[0082]

[0083] In this embodiment, the surface shape x of each aspheric lens can be defined by, but not limited to, the following aspheric surface formula:

[0084]

[0085] Wherein, x is the distance vector height from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface, c=1 / R (i.e., the paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above); k is the cone coefficient; A i The following Table 2 shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, and A20 of the aspheric mirror surfaces S1-S14 that can be used in Example 1.

[0086] Table 2 is a table of high-order coefficients of various aspherical mirror surfaces in Example 1.

[0087]

[0088] Table 3 below shows important parameters in Example 1.

[0089] Table 3 is a table of important parameters of Example 1.

[0090]

[0091] The specific lens structure of this embodiment is as follows Figure 1 As shown in Table 1-3 and Figure 1-3 The lens shape and various properties of the lens of the current embodiment are shown, indicating that the lens achieves a wide angle and high imaging quality.

[0092] Example 2

[0093] The present embodiment provides a wide-angle optical imaging lens, which is composed of a first lens 1, an aperture 8, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7 and a filter 9 in sequence from the object side to the image side along the optical axis. Incident light passes through the above components in sequence and is finally imaged on the image plane. The first lens 1 has positive focal power, and its object side surface is concave at the near optical axis, and the image side surface is convex at the near optical axis. The second lens 2 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The third lens 3 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fourth lens 4 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fifth lens 5 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The sixth lens 6 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The seventh lens 7 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The filter 9 is arranged between the seventh lens 7 and the image plane.

[0094] Table 4 shows the surface type, radius of curvature, thickness and material properties of each lens in Example 2. The units of the radius of curvature and thickness are both millimeters (mm).

[0095] Table 4 is a table of lens parameters of Example 2.

[0096]

[0097]

[0098] In this embodiment, each aspheric surface shape can be defined by the formula (1) in the above embodiment 1. Table 5 below shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20 of each aspheric mirror surface S1-S14 that can be used in embodiment 2.

[0099] Table 5 is a table of high-order coefficients of each aspherical mirror surface in Example 2.

[0100]

[0101]

[0102] Table 6 below shows important parameters in Example 2.

[0103] Table 6 is a table of important parameters of Example 2.

[0104]

[0105] The specific lens structure of this embodiment is as follows Figure 4 Table 4-6 and Figure 4-6 The lens shape and various properties of the lens of the current embodiment are shown, indicating that the lens achieves a wide angle and high imaging quality.

[0106] Example 3

[0107] The present embodiment provides a wide-angle optical imaging lens, which is composed of a first lens 1, an aperture 8, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7 and a filter 9 in sequence from the object side to the image side along the optical axis. Incident light passes through the above components in sequence and is finally imaged on the image plane. The first lens 1 has positive focal power, and its object side surface is concave at the near optical axis, and the image side surface is convex at the near optical axis. The second lens 2 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The third lens 3 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fourth lens 4 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fifth lens 5 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The sixth lens 6 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The seventh lens 7 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The filter 9 is arranged between the seventh lens 7 and the image plane.

[0108] Table 7 shows the surface type, radius of curvature, thickness and material properties of each lens in Example 3. The units of the radius of curvature and thickness are both millimeters (mm).

[0109] Table 7 is a table of lens parameters of Example 3.

[0110]

[0111] In this embodiment, each aspheric surface shape can be defined by the formula (1) in the above embodiment 1. Table 8 below shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20 of each aspheric mirror surface S1-S14 that can be used in embodiment 3.

[0112] Table 8 is a table of high-order coefficients of each aspherical mirror surface in Example 3.

[0113]

[0114]

[0115] Table 9 below shows important parameters in Example 3.

[0116] Table 9 is a table of important parameters of Example 3.

[0117]

[0118] The specific lens structure of this embodiment is as follows Figure 7 As shown in Table 7-9 and Figure 7-9 The lens shape and various properties of the lens of the current embodiment are shown, indicating that the lens achieves a wide angle and high imaging quality.

[0119] Example 4

[0120] The present embodiment provides a wide-angle optical imaging lens, which is composed of a first lens 1, an aperture 8, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7 and a filter 9 in sequence from the object side to the image side along the optical axis. Incident light passes through the above components in sequence and is finally imaged on the image plane. The first lens 1 has positive focal power, and its object side surface is concave at the near optical axis, and the image side surface is convex at the near optical axis. The second lens 2 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The third lens 3 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fourth lens 4 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fifth lens 5 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The sixth lens 6 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The seventh lens 7 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The filter 9 is arranged between the seventh lens 7 and the image plane.

[0121] Table 10 shows the surface type, radius of curvature, thickness and material properties of each lens in Example 4. The units of the radius of curvature and thickness are both millimeters (mm).

[0122] Table 10 is a table of lens parameters of Example 4.

[0123]

[0124]

[0125] In this embodiment, each aspheric surface shape can be defined by the formula (1) in the above embodiment 1. Table 11 below shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20 of each aspheric mirror surface S1-S14 that can be used in embodiment 4.

[0126] Table 11 is a table of high-order coefficients of each aspherical mirror surface in Example 4.

[0127]

[0128] Table 12 below shows important parameters in Example 4.

[0129] Table 12 is a table of important parameters of Example 4.

[0130]

[0131]

[0132] The specific lens structure of this embodiment is as follows Fig.10 Table 10-12 and Figure 10-12 The lens shape and various properties of the lens of the current embodiment are shown, indicating that the lens achieves a wide angle and high imaging quality.

[0133] Example 5

[0134] The present embodiment provides a wide-angle optical imaging lens, which is composed of a first lens 1, an aperture 8, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7 and a filter 9 in sequence from the object side to the image side along the optical axis. Incident light passes through the above components in sequence and is finally imaged on the image plane. The first lens 1 has positive focal power, and its object side surface is concave at the near optical axis, and the image side surface is convex at the near optical axis. The second lens 2 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is convex at the near optical axis. The third lens 3 has negative focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fourth lens 4 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The fifth lens 5 has positive focal power, and its object side surface is concave at the near optical axis, and the image side surface is concave at the near optical axis. The sixth lens 6 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The seventh lens 7 has positive focal power, and its object side surface is convex at the near optical axis, and the image side surface is concave at the near optical axis. The filter 9 is arranged between the seventh lens 7 and the image plane.

[0135] Table 13 shows the surface type, radius of curvature, thickness and material properties of each lens in Example 5. The units of the radius of curvature and thickness are both millimeters (mm).

[0136] Table 13 is a table of lens parameters of Example 5.

[0137]

[0138]

[0139] In this embodiment, each aspheric surface shape can be defined by the formula (1) in the above embodiment 1. Table 14 below shows the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20 of each aspheric mirror surface S1-S14 that can be used in embodiment 5.

[0140] Table 14 is a table of high-order coefficients of each aspherical mirror surface in Example 5.

[0141]

[0142]

[0143] Table 15 below shows important parameters in Example 5.

[0144] Table 15 is a table of important parameters of Example 5.

[0145]

[0146] The specific lens structure of this embodiment is as follows Fig.13 Table 13-15 and Figure 13-15 The lens shape and various properties of the lens of the current embodiment are shown, indicating that the lens achieves a wide angle and high imaging quality.

[0147] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are illustrative and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A wide-angle optical imaging lens, characterized in that: Along the optical axis from the object side to the image side, it is composed of: The first lens has positive power; the object side surface of the first lens is concave at the near optical axis, and the image side surface is convex at the near optical axis; The second lens has a negative optical power; the object side surface of the second lens is convex at the near optical axis, and the image side surface is convex at the near optical axis; The third lens has negative power, and the image side surface of the third lens is concave at the near optical axis; a fourth lens having optical power; a fifth lens having positive refractive power; a sixth lens having positive refractive power; A seventh lens having negative optical power; The first to seventh lenses are all plastic aspherical lenses; The optical imaging lens satisfies the following conditional formula: 1.9111<│(ImgH*tan(FOV)) / TTL│<2.0467 Wherein, ImgH is half of the maximum image height of the optical imaging lens; FOV is the maximum field of view of the optical imaging lens; TTL is the total optical length from the object side of the first lens to the image plane of the optical imaging lens.

2. The wide-angle optical imaging lens according to claim 1, characterized in that: The optical imaging lens satisfies the following conditional formula: 1.99 <f / EPD<2.11 Wherein, f is the effective focal length of the optical imaging lens; EPD is the entrance pupil diameter of the optical imaging lens.

3. The wide-angle optical imaging lens according to claim 1, characterized in that: The optical imaging lens satisfies the following conditional formula: 0.2 <f1 / R2<1.64 Among them, f1 is the focal length of the first lens in the optical imaging lens; R2 is the curvature radius of the image side surface of the first lens in the optical imaging lens.

4. The wide-angle optical imaging lens according to claim 1, wherein: The optical imaging lens satisfies the following conditional formula: 1.82 <TTL / f<1.96 Wherein, f is the effective focal length of the optical imaging lens.

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