Low-total-length 8M foresight main camera

Abstract

The utility model relates to a low total length 8M foresight main camera. An optical system of the main camera is composed of a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged from left to right along a light incident light path. The lenses are made of plastic and glass materials, the first lens, the second lens, the fourth lens, the sixth lens and the seventh lens are glass spherical lenses, the third lens and the fifth lens are plastic aspheric lenses, and the sixth lens and the seventh lens form a balsaming lens group. By reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens, the axial distance between the lenses and the like, the total length of the lens and the radial size of each lens are reduced while the requirements of a front-view wide-angle camera and a front-view narrow-angle camera are replaced by the low-total-length 8M ultra-wide-angle imaging performance of the lens, and the miniaturization of the lens group is realized.

Description

Technical field:

[0001] The utility model relates to the technical field of lenses, in particular to a front-view main camera with a low total length of 8M. Background technology:

[0002] With the continuous development of the automobile industry, forward-looking optical lenses are widely used in intelligent vehicle information systems including autonomous driving technology, collision avoidance warning, lane departure warning and driving records. They are used to collect and identify road condition information such as pedestrians, vehicles and obstacles on the road ahead, thereby improving driving comfort and safety.

[0003] In order to realize the single-lens module, the front-view optical lens needs to meet the advantages of 8M high resolution, large field of view angle, good environmental adaptability, etc. At the same time, it also has disadvantages such as a large number of lenses and a long total optical length, which is not conducive to the miniaturization of the overall system.

[0004] At present, the Chinese patent "A large field of view, high pixel optical system and a mobile phone camera module using the optical system" has been retrieved with publication number CN111045196A, which includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence from the object side to the image side, the first lens is a convex lens, the second lens is a concave lens, the third lens, the fourth lens and the fifth lens are reverse curved lenses, and the image plane diagonal length H of the optical system is achieved by the special design of the aspherical profile shape of the optical system and the reasonable setting of the refractive index of each piece of material. The patented optical system meets the requirements of large image field and high pixel design between 7.80mm-10.50mm, thereby increasing the overall brightness of the optical system and reducing production costs. Although the mobile phone camera module of the patented optical system adopts a deformed elastic body mosaic positioning structure to ensure the stability of the shooting resolution and improve the assembly yield of the camera module; it cannot achieve the visual perception and recognition functions of driving while achieving low-cost 8MP imaging to replace the front wide-angle camera and the front narrow-angle camera, and realize a single-lens front camera module, greatly reducing costs to increase market popularity. Summary of the invention:

[0005] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a low total length 8M front-view main camera, which can achieve low-cost 8MP imaging while realizing the visual perception and recognition functions of driving, so as to replace the front-view wide-angle camera and the front-view narrow-angle camera, and realize a single-lens front-view camera module, thereby greatly reducing costs and increasing market popularity.

[0006] In order to solve the above technical problems, the technical solution of the utility model is:

[0007] A low total length 8M front-view main camera, characterized in that: the optical system of the main camera is composed of a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens and a seventh lens from left to right along the incident light path; the first lens is a meniscus concave negative lens, whose object side surface is convex and whose image side surface is concave; the second lens is a meniscus concave negative lens, whose object side surface is convex and whose image side surface is concave; the third lens is a biconvex positive lens, whose object side surface is convex and whose image side surface is convex; the fourth lens is a biconvex positive lens, whose The object side surface is convex, and the image side surface is convex; the fifth lens is a meniscus convex positive lens, whose object side surface is concave, and the image side surface is convex; the sixth lens is a double concave negative lens, whose object side surface is concave, and the image side surface is concave; the seventh lens is a double convex positive lens, whose object side surface is convex, and the image side surface is convex; the lenses are made of plastic and glass materials, the first, second, fourth, sixth, and seventh lenses are glass spherical lenses, and the third and fifth lenses are plastic aspherical lenses, wherein the image side surface of the sixth lens and the object side surface of the seventh lens are cemented to form a cemented lens group.

[0008] Preferably, the focal length of the optical system is f, and the focal lengths of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are f1, f2, f3, f4, f5, f6, and f7, respectively, wherein f1, f2, f3, f4, f5, f6, and f7 satisfy the following ratio with f: -3.0 <f1 / f<-2.0,-3.0<f2 / f<-2.0,8.0<f3 / f<9.0,2.0<f4 / f<3.0,3.0<f5 / f<4.0,-2.0<f6 / f<-1.0,1.0<f7 / f<2.0。

[0009] Preferably, the first lens satisfies the relationship: 2.0≤N d ≤2.3, V d ≤50.0; the second lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; the third lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; the fourth lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the sixth lens satisfies the relationship: 2.0≤N d ≤2.3, V d ≤50.0; the seventh lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; where N dis the refractive index, V d is the Abbe constant.

[0010] Preferably, the distances between the lenses on the optical axis satisfy the following relationship: the air gap between the first lens and the second lens is 2.0-2.5 mm; the air gap between the second lens and the third lens is 1.0-1.5 mm; the air gap between the third lens and the fourth lens is 0.5-1.0 mm; the air gap between the fourth lens and the aperture is 0.1-0.5 mm; the air gap between the aperture and the fifth lens is 0.5-1.0 mm; the air gap between the fifth lens and the sixth lens is 0.1-0.5 mm; the sixth lens and the seventh lens are glued sheets, and the air gap is 0 mm.

[0011] Preferably, the third and fifth lenses are both aspherical lenses, and the aspherical curve equation is expressed as:

[0012]

[0013] Among them, Z is the height of the aspheric surface from the vertex of the aspheric surface when it is at a height of r along the optical axis; c is the paraxial curvature of the aspheric surface; k is the cone constant; α1, α2, α3, α4, α5, α6, α7, and α8 are all high-order coefficients.

[0014] Preferably, the total optical length TTL of the optical system and the focal length f of the optical system satisfy the following relationship: TTL / f≤10.0.

[0015] Preferably, the F number of the optical system is ≤1.6.

[0016] Preferably, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≥1.0.

[0017] Preferably, a filter is disposed on the rear side of the seventh lens.

[0018] Compared with the prior art, the utility model has the following advantages:

[0019] 1. The imaging angle of the lens to the object is greater than 195 degrees. It has the advantages of ultra-high 8M imaging clarity, large aperture, low tolerance sensitivity and good high and low temperature stability. At the same time, it can monitor the scene outside the car more comprehensively;

[0020] 2. Through the reasonable matching of various optical lenses, the system structure is compact and reasonable, with a total length of 17mm, easy to assemble, low tolerance sensitivity, and more suitable for large-scale high-yield production;

[0021] 3. The glass-plastic hybrid structure has lower manufacturing cost and lighter weight, which is conducive to the manufacture and installation of modules;

[0022] 4. Able to make good compensation for focal plane displacement at high and low temperatures, and have adaptability to complex environments;

[0023] 5. The axial chromatic aberration, vertical chromatic aberration and high-order chromatic aberration are corrected to ensure that the imaging system can have high imaging quality even at a large angle.

[0024] 6. Give full play to the advantages of aspherical lenses in correcting aberrations, meet the requirements of high-definition imaging, have a smaller lens outer diameter and a shorter total optical length, and ensure the miniaturization of the lens.

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Description of the drawings:

[0026] Figure 1 It is a schematic diagram of the optical structure of the utility model;

[0027] Figure 2 It is the axial chromatic aberration diagram of the full working band of the utility model;

[0028] Figure 3 It is the vertical axis chromatic aberration diagram of the full working band of the utility model;

[0029] Figure 4 It is the field curvature distortion diagram of the full working band of the utility model;

[0030] In the figure: STO-aperture; L1-first lens; L2-second lens; L3-third lens; L4-fourth lens; L5-fifth lens; L6-sixth lens; L7-seventh lens; L8-equivalent glass plate; L9-equivalent glass plate; IMA-imaging surface. Specific implementation method:

[0031] The utility model is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0032] like Figure 1As shown, a low total length 8M front-view main camera, the optical system of the main camera is composed of a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture, a fifth lens L5, a sixth lens L6 and a seventh lens L7 from left to right along the incident light path; the first lens is a meniscus concave negative lens, the object side surface of which is convex, and the image side surface is concave; the second lens is a meniscus concave negative lens, the object side surface of which is convex, and the image side surface is concave; the third lens is a biconvex positive lens, the object side surface of which is convex, and the image side surface is convex; the fourth lens is a biconvex positive lens. A positive lens, whose object side surface is convex and whose image side surface is convex; the fifth lens is a meniscus convex positive lens, whose object side surface is concave and whose image side surface is convex; the sixth lens is a double concave negative lens, whose object side surface is concave and whose image side surface is concave; the seventh lens is a double convex positive lens, whose object side surface is convex and whose image side surface is convex; the lenses are made of plastic and glass materials, the first, second, fourth, sixth and seventh lenses are glass spherical lenses, the third and fifth lenses are plastic aspherical lenses, wherein the image side surface of the sixth lens and the object side surface of the seventh lens are cemented to form a cemented lens group.

[0033] The first and second lenses are negative focal length lenses that can adjust large-angle light; the third lens is a plastic aspheric surface that can reduce the distortion of the optical system; the sixth and seventh lenses form an achromatic doublet lens; the reasonable lens combination enables the optical system to achieve low cost, low total length, 8M, ultra-wide angle, large aperture, day and night confocal, low temperature drift design, and at the same time, the on-axis and off-axis aberrations are well corrected, with good imaging quality. Figures 2 to 4 As shown, the technical indicators achieved by the optical system of this embodiment are as follows:

[0034] (1) Focal length: 1.0 ≤ EFFL ≤ 2.0 mm;

[0035] (2) Aperture F ≤ 1.6;

[0036] (3) Field of view: 2w ≥ 195°;

[0037] (4) Working band: visible light band.

[0038] To achieve the above design parameters, the specific design adopted by the optical system of this embodiment is shown in the following table:

[0039]

[0040]

[0041] The aspheric coefficients of the aspheric lenses of the optical system of this embodiment are as follows:

[0042]

[0043] The optical system of this embodiment reasonably distributes the optical focal length, surface shape, center thickness of each lens and the axial distance between each lens, etc., of each lens, thereby meeting the ultra-wide-angle imaging performance requirement of the lens with a low total length of 8M, reducing the total length of the lens and the radial size of each lens, thereby miniaturizing the lens group.

[0044] The above is only the preferred embodiment of the utility model, and does not limit the utility model in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the utility model without departing from the technical solution of the utility model still belongs to the protection scope of the technical solution of the utility model.

Claims

1. A low total length 8M front-view main camera, characterized by: The optical system of the main camera is composed of a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens and a seventh lens from left to right along the incident light path; the first lens is a meniscus concave negative lens, whose object side surface is convex and whose image side surface is concave; the second lens is a meniscus concave negative lens, whose object side surface is convex and whose image side surface is concave; the third lens is a biconvex positive lens, whose object side surface is convex and whose image side surface is convex; the fourth lens is a biconvex positive lens, whose object side surface is convex and whose image side surface is concave. The first, second, fourth, sixth and seventh lenses are glass spherical lenses, and the third and fifth lenses are plastic aspherical lenses. The image side surface of the sixth lens and the object side surface of the seventh lens are cemented together to form a cemented lens group.

2. The low overall length 8M front-view main camera according to claim 1, characterized in that: The focal length of the optical system is f, and the focal lengths of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are f1, f2, f3, f4, f5, f6, and f7, respectively, wherein f1, f2, f3, f4, f5, f6, and f7 satisfy the following ratio with f: -3.0 <f1 / f<-2.0,-3.0<f2 / f<-2.0,8.0<f3 / f<9.0,2.0<f4 / f<3.0,3.0<f5 / f<4.0,-2.0<f6 / f<-1.0,1.0<f7 / f<2.0。 3. The low overall length 8M front-view main camera according to claim 2, characterized in that: The first lens satisfies the relationship: 2.0≤N d ≤2.3, V d ≤50.0; the second lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; the third lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; the fourth lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≥50.0; the sixth lens satisfies the relationship: 2.0≤N d ≤2.3, V d ≤50.0; the seventh lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; where N d is the refractive index, V d is the Abbe constant.

4. The low overall length 8M front-view main camera according to claim 1, 2 or 3, characterized in that: The distances between the lenses on the optical axis satisfy the following relationship: the air gap between the first lens and the second lens is 2.0-2.5 mm; the air gap between the second lens and the third lens is 1.0-1.5 mm; the air gap between the third lens and the fourth lens is 0.5-1.0 mm; the air gap between the fourth lens and the diaphragm is 0.1-0.5 mm; the air gap between the diaphragm and the fifth lens is 0.5-1.0 mm; the air gap between the fifth lens and the sixth lens is 0.1-0.5 mm; the sixth lens and the seventh lens are glued sheets, and the air gap is 0 mm.

5. The low overall length 8M front-view main camera according to claim 1, 2 or 3, characterized in that: The third and fifth lenses are both aspherical lenses, and the aspherical curve equation is expressed as: Among them, Z is the height of the aspheric surface from the vertex of the aspheric surface when it is at a height of r along the optical axis; c is the paraxial curvature of the aspheric surface; k is the cone constant; α1, α2, α3, α4, α5, α6, α7, and α8 are all high-order coefficients.

6. The low overall length 8M front-view main camera according to claim 1, 2 or 3, characterized in that: The total optical length TTL of the optical system and the focal length f of the optical system satisfy the following conditions: TTL / f≤10.0, and the F number of the optical system≤1.

6.

7. The low overall length 8M front-view main camera according to claim 1, 2 or 3, characterized in that: The image height H of the optical system and the focal length f of the optical system satisfy: H / f≥1.

0.

8. The low overall length 8M front-view main camera according to claim 1, 2 or 3, characterized in that: A filter is arranged on the rear side of the seventh lens.

9. The low overall length 8M front-view main camera according to claim 1, 2 or 3, characterized in that: The technical indicators achieved by the optical system are as follows: (1) Focal length: 1.0 ≤ EFFL ≤ 2.0 mm; (2) Aperture F ≤ 1.6; (3) Field of view: 2w ≥ 195°; (4) Working band: visible light band.

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