An 8M front-view main camera suitable for vehicle-mounted front-view cameras

Abstract

The present invention discloses an 8M front-view main camera suitable for vehicle-mounted front-view photography. The optical system of the lens comprises a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, which are arranged in sequence from left to right along an incident light path of light. The first lens is a meniscus negative lens, the second lens is a meniscus negative lens, the third lens is a biconvex positive lens, the fourth lens is a biconvex positive lens, the fifth lens is a biconcave negative lens, the sixth lens is a biconvex positive lens, and the seventh lens is a meniscus positive lens. The lenses are made of glass material, the second and seventh lenses are glass aspheric lenses, and the fifth and sixth lenses are a cemented lens group. By reasonably allocating the optical power, surface shape, center thickness of each lens, and axial distance between each lens, the total length of the lens and the radial size of each lens are reduced while meeting the imaging performance requirements of the 8M lens, thereby achieving miniaturization of the lens group.

Description

Technical Field

[0001] The present invention relates to the field of lens technology, and in particular to an 8M front-view main camera suitable for vehicle-mounted front-view photography. Background Art

[0002] With the development of the economy and the improvement of people's quality of life, the annual sales of automobiles in my country have exceeded 10 million. As the number of cars in cities increases, roads are becoming more and more crowded, and the problem of frequent traffic accidents has become increasingly prominent. In order to reduce the occurrence of traffic accidents and protect their lives and property, people are more willing to buy cars with automobile safety technologies when purchasing cars.

[0003] Automobile safety technologies include: lane departure warning, active collision avoidance, adaptive cruise control, traction control, etc.; among them, the on-board forward-view camera system is an automobile safety technology with lane departure warning function, and the on-board forward-view camera module plays an important role as the hardware terminal of the system.

[0004] The current vehicle-mounted front-view camera module can be divided into three structures: a front-view main camera, a front-view wide-angle camera, and a front-view narrow-angle camera. However, although the use of three cameras can achieve the corresponding functions, it greatly increases the cost of the entire camera module, which is not conducive to market popularization. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the technical problem to be solved by the present invention is to provide an 8M front-view main camera suitable for vehicle-mounted front-view cameras, which can realize 8MP imaging while realizing the visual perception and recognition functions of driving, thereby replacing the front-view wide-angle camera and the front-view narrow-angle camera, realizing a single-lens front-view camera module, which can greatly reduce costs and increase market popularity.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: an 8M front-view main camera suitable for vehicle-mounted front-view photography, the optical system of the lens includes a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence from left to right along the incident light path of the light; without considering the back curvature caused by the aspheric coefficient, the first lens is a meniscus negative lens, the object side surface of which is convex and the image side surface is concave; the second lens is a meniscus negative lens, the object side surface of which is concave and the image side surface is convex; the third lens is a double convex positive lens , its object-side surface is convex, and its image-side surface is convex; the fourth lens is a biconvex positive lens, its object-side surface is convex, and its image-side surface is convex; the fifth lens is a biconcave negative lens, its object-side surface is concave, and its image-side surface is concave; the sixth lens is a biconvex positive lens, its object-side surface is convex, and its image-side surface is convex; the seventh lens is a meniscus positive lens, its object-side surface is convex, and its image-side surface is concave; the lenses are made of glass material, the first, third, fourth, fifth, and sixth lenses are glass spherical lenses, the second and seventh lenses are glass aspherical lenses, and the fifth and sixth lenses are cemented lens groups;

[0007] The focal length of the optical system is 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 、 、 、 、 、 、 ,in 、 、 、 、 、 、 and Meet the following ratio: -3.0< / <-2.0, -5.0< / <-4.0, 2.0< / <3.0, 2.0< / <3.0, -2.0< / <-1.0, 1.0< / <2.0, 17.0 < / <18.0.

[0008] Preferably, the first lens satisfies the relationship: 1.5≤ ≤1.8, ≤50.0; the second lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the third lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the fourth lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the fifth lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the sixth lens satisfies the relationship: 1.5≤ ≤1.8, ≥50.0; the seventh lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; where is the refractive index, is the Abbe constant.

[0009] Preferably, the on-axis distances between the lenses satisfy the following relationship: the air gap between the first lens and the second lens is 4.1-4.5 mm; the air gap between the second lens and the third lens is 0.1-0.5 mm; the air gap between the third lens and the aperture is 1.5-2.0 mm; the air gap between the aperture and the fourth lens is 0.1-0.5 mm; the air gap between the fourth lens and the fifth lens is 0.1-0.5 mm; the fifth lens and the sixth lens are cemented sheets with an air gap of 0 mm; and the air gap between the sixth lens and the seventh lens is 1.0-1.5 mm.

[0010] Preferably, the second and seventh lenses are both aspheric lenses. The aspheric curve equation is:

[0011]

[0012] Where Z is the height of the aspheric surface from the vertex of the aspheric surface at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface; k is the conic constant; 、 、 、 、 、 、 、 All are high-order coefficients.

[0013] 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≤8.0; focal length: 3.0≤EFFL≤4.0 mm.

[0014] Preferably, the aperture F number of the optical system is ≤1.6; the field of view angle: 2w ≥140°.

[0015] Preferably, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≥1.0.

[0016] Preferably, a filter is provided on the rear side of the seventh lens.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The lens has an imaging angle of more than 140 degrees and 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 vehicle more comprehensively.

[0019] 2. Through the reasonable matching of optical lenses, the system structure is compact and reasonable, easy to assemble, with low tolerance sensitivity, and more suitable for large-scale high-yield production;

[0020] 3. The all-glass structure has high stability and can adapt to harsh environments;

[0021] 4. Able to make good compensation for focal plane displacement at high and low temperatures, and have adaptability to complex environments;

[0022] 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 large angles.

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the optical structure of the present invention;

[0025] Figure 2 This is the full working band axial chromatic aberration diagram of the present invention;

[0026] Figure 3 This is the vertical axis chromatic aberration diagram of the full working band of the present invention;

[0027] Figure 4 This is the field curvature distortion diagram of the full working band of the present invention;

[0028] 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. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to the accompanying drawings and specific implementation methods.

[0030] like Figure 1 As shown, the technical solution of the present invention is: an 8M front-view main camera suitable for vehicle-mounted front-view photography, the optical system of the lens includes a first lens L1, a second lens L2, a third lens L3, an aperture STO, a fourth lens L4, a fifth lens L5, a sixth lens L6 and a seventh lens L7 arranged in sequence from left to right along the incident light path of the light; without considering the back curvature caused by the aspheric coefficient, the first lens is a meniscus negative lens, the object side surface of which is convex and the image side surface is concave; the second lens is a meniscus negative lens, the object side surface of which is concave and the image side surface is convex; the third lens is a double A convex positive lens with a convex object-side surface and a convex image-side surface; the fourth lens is a biconvex positive lens with a convex object-side surface and a convex image-side surface; the fifth lens is a biconcave negative lens with a concave object-side surface and a concave image-side surface; the sixth lens is a biconvex positive lens with a convex object-side surface and a convex image-side surface; the seventh lens is a meniscus positive lens with a convex object-side surface and a concave image-side surface; the lenses are made of glass; the first, third, fourth, fifth, and sixth lenses are glass spherical lenses, the second and seventh lenses are glass aspherical lenses, and the fifth and sixth lenses are cemented lenses;

[0031] The focal length of the optical system is 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 、、 、 、 、 、 ,in 、 、 、 、 、 、 and Meet the following ratio: -3.0< / <-2.0, -5.0< / <-4.0, 2.0< / <3.0, 2.0< / <3.0, -2.0< / <-1.0, 1.0< / <2.0, 17.0< / <18.0.

[0032] The first lens satisfies the relationship: 1.5≤ ≤1.8, ≤50.0; the second lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the third lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the fourth lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; the fifth lens satisfies the relationship: 1.7≤≤2.0, ≤50.0; the sixth lens satisfies the relationship: 1.5≤ ≤1.8, ≥50.0; the seventh lens satisfies the relationship: 1.7≤ ≤2.0, ≤50.0; where is the refractive index, is the Abbe constant.

[0033] The axial distances between the lenses satisfy the following relationship: the air gap between the first and second lenses is 4.1-4.5 mm; the air gap between the second and third lenses is 0.1-0.5 mm; the air gap between the third lens and the aperture is 1.5-2.0 mm; the air gap between the aperture and the fourth lens is 0.1-0.5 mm; the air gap between the fourth and fifth lenses is 0.1-0.5 mm; the fifth and sixth lenses are cemented together and have an air gap of 0 mm; and the air gap between the sixth and seventh lenses is 1.0-1.5 mm.

[0034] The second and seventh lenses are both aspherical lenses, and the aspherical curve equation is:

[0035]

[0036] Where Z is the height of the aspheric surface from the vertex of the aspheric surface at a height of h along the optical axis; c is the paraxial curvature of the aspheric surface; k is the conic constant; 、 、 、 、 、 、 、 All are high-order coefficients.

[0037] The total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤8.0; the image height H of the optical system and the focal length f of the optical system satisfy: H / f≥1.0; and a filter is provided on the rear side of the seventh lens.

[0038] The first and second lenses are both glass spherical lenses with negative optical power, which adjust large-angle light. The glass aspherical surface has the function of reducing optical system distortion. The fifth and sixth lenses form an achromatic doublet lens. The reasonable lens combination enables the optical system to achieve 8M, ultra-wide angle, large aperture, day and night confocal, low-temperature drift design, and at the same time, it has carried out good correction for on-axis and off-axis aberrations, with good imaging quality. Figures 2 to 4 As shown, the technical indicators achieved by the optical system of this embodiment are as follows:

[0039] (1) Focal length: 3.0 ≤ EFFL ≤ 4.0 mm;

[0040] (2) Aperture F ≤ 1.6;

[0041] (3) Field of view: 2w ≥ 140°;

[0042] (4) Working band: visible light band.

[0043] To achieve the above design parameters, the specific design adopted by the optical system of this embodiment is shown in the following table:

[0044]

[0045] The aspheric coefficients of the aspheric lenses of the optical system of this embodiment are as follows:

[0046] The optical system of this embodiment achieves miniaturization of the lens group by reasonably allocating the optical focal length, surface shape, center thickness of each lens, and axial distance between lenses, thereby meeting the imaging performance requirements of the lens 8M while reducing the total length of the lens and the radial size of each lens.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

Claims

1. An 8M front-view main camera suitable for vehicle-mounted front-view photography, characterized by: The optical system of the front-view main camera is composed of a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, a sixth lens and a seventh lens, which are arranged in sequence from left to right along the incident light path of the light; without considering the back curvature caused by the aspheric coefficient, the first lens is a meniscus negative lens, whose object side surface is convex and whose image side surface is concave; the second lens is a meniscus negative lens, whose object side surface is concave and whose image side surface is convex; 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 double convex positive lens, whose object side surface is convex and whose image side surface is convex; The lens is a biconvex positive lens with a convex object-side surface and a convex image-side surface; the fifth lens is a biconcave negative lens with a concave object-side surface and a concave image-side surface; the sixth lens is a biconvex positive lens with a convex object-side surface and a convex image-side surface; the seventh lens is a meniscus positive lens with a convex object-side surface and a concave image-side surface; the lenses are made of glass; the first, third, fourth, fifth, and sixth lenses are glass spherical lenses, and the second and seventh lenses are glass aspherical lenses. The fifth and sixth lenses are cemented lenses. 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. Among them, f1, f2, f3, f4, f5, f6, and f7 satisfy the following ratios with f: -3.0 < f1 / f < -2.0, -5.0 < f2 / f < -4.0, 2.0 < f3 / f < 3.0, 2.0 < f4 / f < 3.0, -2.0 < f5 / f < -1.0, 1.0 < f6 / f < 2.0, 17.0 < f7 / f < 18.0; the first lens satisfies the relationship: 1.5 ≤ N d ≤ 1.8, V d ≤ 50.0; the second lens satisfies the relationship: 1.7 ≤ N d ≤ 2.0, V d ≤ 50.0; the third lens satisfies the relationship: 1.7 ≤ N d ≤ 2.0, 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: 1.7 ≤ N d ≤ 2.0, V d ≤ 50.0; the sixth lens satisfies the relationship: 1.5 ≤ N d ≤ 1.8, 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, and V d is the Abbe number; the F-number of the aperture of the optical system ≤ 1.6; Field of view: 2w≥140°.

2. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 1, characterized in that: The axial distances between the lenses satisfy the following relationship: the air gap between the first lens and the second lens is 4.1 to 4.5 mm; the air gap between the second lens and the third lens is 0.1 to 0.5 mm; the air gap between the third lens and the aperture is 1.5 to 2.0 mm; the air gap between the aperture and the fourth lens is 0.1 to 0.5 mm; the air gap between the fourth lens and the fifth lens is 0.1 to 0.5 mm; the fifth lens and the sixth lens are cemented sheets with an air gap of 0 mm; and the air gap between the sixth lens and the seventh lens is 1.0 to 1.5 mm.

3. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 2, characterized in that: The second and seventh 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 h 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.

4. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 1, characterized in that: The total optical length TTL of the optical system and the focal length f of the optical system satisfy the following relationship: TTL / f≤8.0; Focal length: 3.0≤EFFL≤4.0mm.

5. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 4, characterized in that: The image height H of the optical system and the focal length f of the optical system satisfy the following relationship: H / f≥1.

0.

6. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 5, characterized in that: A filter is provided on the rear side of the seventh lens.

7. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 1, characterized in that: The specific parameters of the optical system are shown in the following table:

8. The 8M front-view main camera for vehicle-mounted front-view photography according to claim 7, characterized in that: The aspheric coefficients of the aspheric lenses of the optical system are as follows:

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