8m front-view main camera for vehicle-mounted front-view camera and imaging method thereof

Abstract

The application relates to an 8M front-view main camera suitable for vehicle-mounted front-view photography and an imaging method thereof. The optical system of the camera is composed of a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens, a sixth lens and a seventh lens. The first lens is a meniscus concave negative lens, the second lens is a meniscus concave positive lens, the third lens is a double-convex positive lens, the fourth lens is a double-convex positive lens, the fifth lens is a double-convex positive lens, the sixth lens is a double-concave negative lens, and the seventh lens is a double-convex positive lens. The fifth lens and the sixth lens form a cemented lens. The third lens, the fourth lens, the fifth lens and the sixth lens are glass spherical lenses, and the first lens, the second lens and the seventh lens are glass aspherical lenses. While realizing the visual perception and recognition function of driving, 8MP imaging is realized, so as to replace the front-view wide-angle camera and the front-view narrow-angle camera, realize a front-view camera module composed of a single lens, greatly reduce the cost and improve the market popularity.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of lenses, and particularly relates to an 8M front-view main camera suitable for vehicle front-view imaging and an imaging method thereof. BACKGROUND

[0002] At present, vehicle-mounted cameras mounted on vehicles are mainly divided into five categories according to installation positions, namely front-view cameras, surround-view cameras, rear-view cameras, side-view cameras and built-in cameras. The front-view cameras are mainly installed on the front windshield and are used to realize the visual perception and recognition function of driving, and can be divided into front-view main cameras, front-view narrow-angle cameras and front-view wide-angle cameras according to functions, but the adoption of the three cameras greatly increases the cost of the entire camera module, which is not conducive to market popularization. The function of the front-view wide-angle camera is mainly to recognize objects at a relatively close distance, and it is mainly used in urban road working conditions, low-speed driving and other scenes, and the field of view is 120°-150° and the detection distance is about 50 m. Therefore, if an 8MP lens is adopted on a large scale, the camera is not needed. SUMMARY

[0003] The application improves the prior art, and the technical problem to be solved by the application is to provide an 8M front-view main camera suitable for vehicle front-view imaging and an imaging method thereof, which is reasonable in design, realizes the visual perception and recognition function of driving, and realizes 8MP imaging.

[0004] In order to achieve the above purpose, the technical scheme adopted by the application is as follows: an 8M front-view main camera suitable for vehicle front-view imaging, an optical system of the 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 arranged in sequence from left to right along the light incident path, the first lens is a meniscus concave negative lens, the second lens is a meniscus concave positive lens, the third lens is a double-convex positive lens, the fourth lens is a double-convex positive lens, the fifth lens is a double-convex positive lens, the sixth lens is a double-concave negative lens, and the seventh lens is a double-convex positive lens, the fifth lens and the sixth lens form a cemented lens group, the third lens, the fourth lens, the fifth lens and the sixth lens are all glass spherical lenses, and the first lens, the second lens and the seventh lens are all glass aspherical lenses.

[0005] Further, the object side of the first lens is a convex surface, and the image side is a concave surface; the object side of the second lens is a convex surface, and the image side is a concave surface; the object side of the third lens is a convex surface, and the image side is a convex surface; the object side of the fourth lens is a convex surface, and the image side is a convex surface; the object side of the fifth lens is a convex surface, and the image side is a convex surface; the object side of the sixth lens is a concave surface, and the image side is a concave surface; and the object side of the seventh lens is a convex surface, and the image side is a convex surface.

[0006] Further, the on-axis distance between each lens satisfies the following relationship, the air gap between the first lens and the second lens is: 1.5-2.0mm; the air gap between the second lens and the third lens is: 6.0-6.5mm; the air gap between the third lens and the diaphragm is: 0.5-1.0mm; the air gap between the diaphragm and the fourth lens is: 0.0-0.5mm; the air gap between the fourth lens and the fifth lens is: 0.1-0.5mm; the air gap between the sixth lens and the seventh lens is: 0.5-1.0mm.

[0007] Further, 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

[0008] Further, the first lens satisfies the relationship: 1.5 d ≤1.8, V d ≤50.0; the second lens satisfies the relationship: 1.7 d ≤2.0, V d ≤50.0; the third lens satisfies the relationship: 1.7 d ≤2.0, V d ≤50.0; the fourth lens satisfies the relationship: 1.7 d ≤2.0, V d ≤50.0; the fifth lens satisfies the relationship: 1.5 d ≤1.8, V d ≥50.0; the sixth lens satisfies the relationship: 1.7 d ≤2.0, V d ≤50.0; the seventh lens satisfies the relationship: 1.7 d ≤2.0, V d ≤50.0; wherein N d is the refractive index, and V d is the Abbe number.

[0009] Further, the aspherical curve equation expression of the first lens, the second lens, and the seventh lens is:

[0010]

[0011] Wherein, Z is the sagittal height of the aspheric surface from the vertex of the aspheric surface along the optical axis at a position with a height of r; c is the paraxial curvature of the aspheric surface; k is the conic constant; and alpha1, alpha2, alpha3, alpha4, alpha5, alpha6, alpha7 and alpha8 are all high-order term coefficients.

[0012] Further, the total track length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤5.0.

[0013] Further, the F number of the optical system is ≤1.6.

[0014] Further, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≤1.0.

[0015] Another technical solution adopted by the present application is: an imaging method of an 8M front-view main camera suitable for vehicle-mounted front-view camera imaging, in which the light path sequentially enters a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens, a sixth lens, a seventh lens, a filter and a protective glass to perform imaging.

[0016] Compared with the prior art, the present application has the following effects: the present application has reasonable design, realizes 8MP imaging while realizing the visual perception and recognition function of driving, thereby replacing the front-view wide-angle camera and the front-view narrow-angle camera, realizing a single lens to form a front-view camera module, greatly reducing the cost and improving the market popularity. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is the optical structure schematic diagram of the embodiment of the present application;

[0018] Figure 2 is the full working waveband axial chromatic aberration diagram of the embodiment of the present application;

[0019] Figure 3 is the full working waveband transverse chromatic aberration diagram of the embodiment of the present application;

[0020] Figure 4 is the full working waveband field curvature distortion diagram of the embodiment of the present application.

[0021] IN THE DRAWINGS

[0022] STO-diaphragm; L1-first lens; L2-second lens; L3-third lens; L4-fourth lens; L5-fifth lens; L6-sixth lens; L7-seventh lens; L8-filter; L9-protective glass; IMA-imaging surface. DETAILED DESCRIPTION

[0023] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0024] As Figure 1 As shown in the figure, the application is an 8M front view main camera for vehicle front view camera, the optical system of the camera is composed of first lens L1, second lens L2, third lens L3, diaphragm STO, fourth lens L4, fifth lens L5, sixth lens L6 and seventh lens L7 arranged in order from left to right along the light path of light incidence, without considering the reverse bending caused by aspherical coefficient, the first lens is a meniscus concave negative lens, the second lens is a meniscus concave positive lens, the third lens is a double convex positive lens, the fourth lens is a double convex positive lens, the fifth lens is a double convex positive lens, the sixth lens is a double concave negative lens, and the seventh lens is a double convex positive lens, the fifth lens and the sixth lens form a cemented lens group, each lens is made of glass material, specifically: the third lens, the fourth lens, the fifth lens and the sixth lens are glass spherical lenses, the first lens, the second lens and the seventh lens are glass aspherical lenses, which can reduce the distortion of the optical system, among them, the aspherical glass lens with negative focal length can adjust the large angle light; the fifth lens and the sixth lens form an achromatic double cemented lens.

[0025] In this embodiment, the object side of the first lens is convex, and the image side is concave; the object side of the second lens is convex, and the image side is concave; the object side of the third lens is convex, and the image side is convex; the object side of the fourth lens is convex, and the image side is convex; the object side of the fifth lens is convex, and the image side is convex; the object side of the sixth lens is concave, and the image side is concave; the object side of the seventh lens is convex, and the image side is convex.

[0026] In this embodiment, the on-axis distance between each lens satisfies the following relationship, the air gap between the first lens and the second lens is: 1.5-2.0mm; the air gap between the second lens and the third lens is: 6.0-6.5mm; the air gap between the third lens and the diaphragm is: 0.5-1.0mm; the air gap between the diaphragm and the fourth lens is: 0.0-0.5mm; the air gap between the fourth lens and the fifth lens is: 0.1-0.5mm; the air gap between the sixth lens and the seventh lens is: 0.5-1.0mm.

[0027] In this embodiment, 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: -3.0

[0028] In this embodiment, 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: 1.5≤N d ≤1.8, V d ≥50.0; the sixth lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; the seventh lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; wherein N d is the refractive index, and V d is the Abbe number.

[0029] In this embodiment, the aspherical surface curve equation expressions of the first lens, the second lens and the seventh lens are as follows:

[0030]

[0031] wherein Z is the sagittal height of the aspherical surface at a position along the optical axis direction at a height of r from the vertex of the aspherical surface; c is the paraxial curvature of the aspherical surface; k is the conic constant; α1, α2, α3, α4, α5, α6, α7 and α8 are high-order term coefficients.

[0032] Specifically, the aspherical surface coefficients of each aspherical lens of the optical system are as follows:

[0033]

[0034] In this embodiment, the total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤5.0.

[0035] In this embodiment, the F number of the optical system is ≤1.6.

[0036] In this embodiment, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≤1.0.

[0037] In this embodiment, the right side of the seventh lens is provided with a filter L8, and the right side of the filter is provided with a protective glass L9.

[0038] In this embodiment, the reasonable lens matching makes the optical system achieve 8M, super wide angle, large aperture, day and night confocal, low temperature drift design, and the on-axis and off-axis aberrations are well corrected, and the imaging quality is good, as shown in FIG. 8. Figures 2 to 4 The technical indexes achieved by the optical system in this embodiment are as follows:

[0039] (1) focal length: 5.0≤EFFL≤6.0mm;

[0040] (2) aperture F≤1.6;

[0041] (3) field of view angle: 2w≥171°;

[0042] (4) working waveband: visible light waveband.

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

[0044]

[0045] In this embodiment, the optical system reasonably allocates the focal power, surface shape, central thickness of each lens, and on-axis distance between each lens, etc., to meet the 8M imaging performance requirements of the lens, while reducing the total length of the lens and the radial size of each lens, achieving miniaturization of the lens group.

[0046] In this embodiment, when the 8M front-view main camera for vehicle-mounted front-view camera imaging, the light path sequentially enters the first lens, the second lens, the third lens, the diaphragm, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the filter and the protective glass for imaging.

[0047] The advantages of the present application are:

[0048] 1. The imaging angle of the camera to the object is greater than 171 degrees, and at the same time, it has the advantages of super high 8M imaging clarity, large light aperture, low tolerance sensitivity and good high and low temperature stability, etc. At the same time, it can more comprehensively monitor the scene outside the vehicle;

[0049] 2. By reasonably matching each optical lens, the system structure is compact and reasonable, easy to assemble, low tolerance sensitivity, more suitable for large-scale high-yield production;

[0050] 3. The all-glass structure has high stability, can adapt to harsh environments, and fully utilizes the advantages of aspherical lens in correcting aberrations, meets high-definition imaging, has smaller lens outer diameter and shorter optical total length, and ensures the miniaturization of the lens.

[0051] 4. It can make good compensation for the focal plane displacement at high and low temperatures, and has complex environment adaptability;

[0052] 5. Corrected each axial chromatic aberration, off-axis chromatic aberration and high-order chromatic aberration, and ensured that the imaging system can have high imaging quality at a large angle.

[0053] If the present application discloses or involves mutually fixedly connected parts or structural members, unless otherwise stated, the fixed connection can be understood as: detachably fixedly connected (for example, connected by bolts or screws), and can also be understood as: non-detachable fixed connection (for example, riveting, welding), of course, the mutually fixed connection can also be replaced by an integral structure (for example, integrally formed by using casting process) (obviously, the integral forming process cannot be used).

[0054] In addition, the terms used to represent the positional relationship or shape in any of the technical solutions disclosed in the present application include states or shapes similar, similar or close to them, unless otherwise stated.

[0055] Any component provided by the present application can be assembled from multiple individual components, or can be a single component manufactured by an integral forming process.

[0056] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application and not to limit them; although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that: the specific embodiments of the present application can still be modified or some technical features can be replaced by equivalents; without departing from the spirit of the technical solutions of the present application, they should be covered in the technical solution range of the present application claimed.

Claims

1. An 8M front-view main camera for vehicle-mounted front-view camera shooting, characterized in that: The optical system of the camera is composed of a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens, a sixth lens and a seventh lens arranged in sequence from left to right along the light incident path, the first lens is a meniscus concave negative lens, the second lens is a meniscus concave positive lens, the third lens is a double-convex positive lens, the fourth lens is a double-convex positive lens, the fifth lens is a double-convex positive lens, the sixth lens is a double-concave negative lens, and the seventh lens is a double-convex positive lens, the fifth lens and the sixth lens form a cemented lens group, the third lens, the fourth lens, the fifth lens and the sixth lens are all glass spherical lenses, and the first lens, the second lens and the seventh lens are all glass aspherical lenses; the object side of the first lens is convex, and the image side is concave; the object side of the second lens is convex, and the image side is concave; the object side of the third lens is convex, and the image side is convex; the object side of the fourth lens is convex, and the image side is convex; the object side of the fifth lens is convex, and the image side is convex; the object side of the sixth lens is concave, and the image side is concave; the object side of the seventh lens is convex, and the image side is convex; the axial distance between each lens satisfies the following relationship, the air gap between the first lens and the second lens is 1.800mm; the air gap between the second lens and the third lens is 6.094mm; the air gap between the third lens and the diaphragm is 0.892mm; the air gap between the diaphragm and the fourth lens is 0.050mm; the air gap between the fourth lens and the fifth lens is 0.250mm; and the air gap between the sixth lens and the seventh lens is 0.660mm.

2. The 8M forward-looking main camera for vehicle-mounted forward-looking 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 and f satisfy the following proportions: -3.0 3. The 8M forward-looking main camera for vehicle-mounted forward-looking camera according to claim 1, characterized in that: 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: 1.5 ≤ N d ≤ 1.8, V d ≥ 50.0; the sixth lens satisfies the relationship: 1.7 ≤ N d ≤ 2.0, V d ≤ 50.0; the seventh lens satisfies the relationship: 1.7 ≤ N d ≤ 2.0, V d ≤ 50.0; wherein N d is the refractive index, and V d is the Abbe number.

4. The 8M forward-looking main camera for vehicle-mounted forward-looking camera according to claim 1, characterized in that: The aspherical surface curve equation expression of the first lens, the second lens and the seventh lens is: wherein Z is the sagitta height of the aspherical surface at a position with a height of r along the optical axis from the vertex of the aspherical surface; c is the paraxial curvature of the aspherical surface; k is the conic constant; and α1, α2, α3, α4, α5, α6, α7 and α8 are high-order coefficients.

5. The 8M forward-looking main camera for vehicle-mounted forward-looking camera 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: TTL / f≤5.

0.

6. The 8M forward-looking main camera for vehicle-mounted forward-looking camera according to claim 1, characterized in that: The F number of the optical system is ≤1.

6.

7. The 8M forward-looking main camera for vehicle-mounted forward-looking camera according to claim 1, 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. An imaging method of an 8M front-view main camera suitable for vehicle-mounted front-view camera, characterized in that: The application relates to a 8M front-view main camera adopting the front-view camera suitable for vehicle use as claimed in any one of claims 1-7, and the light path sequentially enters the first lens, the second lens, the third lens, the diaphragm, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the filter and the protective glass to form an image.

Images