A vehicle-mounted front view lens

Abstract

The present invention provides a vehicle-mounted front-view lens, which overcomes the shortcomings of the prior art and enables the lens to have high resolution, large aperture, and large pixel. It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a parallel flat plate, and an image plane IMA in order from the object side to the image side along the optical axis; the first lens has positive focal power, specifically a first meniscus positive lens, and its object side is concave; the second lens has positive focal power, specifically a second meniscus positive lens, its object side is convex, and its image side is concave; the third lens has negative focal power, specifically a third biconcave negative lens, its object side is concave, and its image side is concave; the fourth lens has positive focal power, and its object side is convex; the fifth lens has positive focal power, and its object side is convex, and its image side is convex; the sixth lens has negative focal power, and its object side is concave, and its image side is concave.

Description

Technical Field

[0001] The invention relates to the technical field of lens structures, in particular to a vehicle-mounted front-view lens. Background Art

[0002] In recent years, with the development of vehicle-mounted technology, the technical requirements for vehicle-mounted cameras such as front-view cameras, automatic cruise control, and driving recorders have become increasingly higher. Among them, the front-view vehicle-mounted lens is an important part of the advanced driver assistance system. The driver can use the front-view vehicle-mounted lens to detect obstacles in front of the car and avoid driving accidents.

[0003] However, the images taken by existing forward-looking cameras have low resolution and a small depth of field. They are unable to present long-distance details while shooting in low-light environments. As a result, the driving assistance system cannot accurately judge the environmental information in front of the vehicle in real time and make timely warnings or avoidance, which poses a driving risk. Summary of the invention

[0004] In view of the above problems, the present invention provides a vehicle-mounted front-view lens, which overcomes the deficiencies of the prior art and enables the lens to have high resolution, large aperture, and large pixel.

[0005] A vehicle-mounted front-view lens, characterized in that it comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a parallel flat plate, and an image plane IMA in sequence from the object side to the image side along the optical axis;

[0006] The first lens has positive focal power, and is specifically a first meniscus positive lens, and its object side surface is concave;

[0007] The second lens has positive power and is specifically a second meniscus positive lens, the object side surface of which is convex and the image side surface is concave;

[0008] The third lens has negative optical power, and is specifically a third biconcave negative lens, whose object side surface is concave and image side surface is concave;

[0009] The fourth lens has positive refractive power, and its object side surface is convex;

[0010] The fifth lens has positive refractive power, and its object side surface is convex, and its image side surface is convex;

[0011] The sixth lens has negative optical power, and its object side surface is concave, and its image side surface is concave.

[0012] It is further characterized by:

[0013] The image side surface of the first lens is concave or convex;

[0014] The fifth lens and the sixth lens are combined to form a cemented lens;

[0015] The fifth lens and the sixth lens are separate lenses;

[0016] The image side surface of the fourth lens is concave or convex;

[0017] The difference between the beta numbers V1 and V2 of at least two adjacent lenses among the six lenses satisfies: 10<|V1-V2|<40;

[0018] BFL is the distance from the center of the image side surface of the sixth lens to the imaging surface of the optical lens on the optical axis, TTL is the distance from the center of the object side surface of the first lens to the imaging surface of the optical lens on the optical axis, and the entire lens satisfies the condition: BFL / TTL≤0.3;

[0019] FOV is the maximum field of view of the optical lens, D is the maximum aperture of the first lens object side corresponding to the maximum field of view of the optical lens, h is the half image height corresponding to the maximum field of view of the optical lens, and the entire lens meets the condition: FOV / h / D≤0.65;

[0020] The maximum field of view angle FOV of the optical lens, the entire focal length value F of the optical lens, and the half image height h corresponding to the maximum field of view angle of the optical lens satisfy the following: (FOV×F) / h≥55;

[0021] The entire lens meets the following conditions: TTL / F≤2;

[0022] f1, f2, f3, f4, f5, f6 are the focal lengths of the first to sixth lenses respectively, and the entire lens satisfies the conditions: 2≤f1 / F≤infinity, 0.3≤f2 / F≤5, -20≤f3 / F≤-0.4, -0.2≤f4 / F≤1.5, -0.5≤f5 / F≤0.8, -3≤f6 / F≤0.

[0023] The present invention adopts six lenses, the first lens has positive focal power, specifically is a first meniscus positive lens, and its object side surface is concave, the second lens has positive focal power, specifically is a second meniscus positive lens, its object side surface is convex, and its image side surface is concave, the third lens has negative focal power, specifically is a third double concave negative lens, its object side surface is concave, and its image side surface is concave, the six glass spherical lenses are combined to form an integral lens, which has a simple structure and a small size, can achieve clear imaging in the range of -40° to 125°, has a small temperature drift, meets the 2 million pixel imaging requirements, has a large aperture, and can shoot a field of view of 38°. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of a lens of the present invention;

[0025] Figure 2 is an MTF curve diagram of a specific embodiment of the present invention;

[0026] Figure 3 FIG. 4 is an illumination curve diagram of an imaging lens according to a specific embodiment of the present invention.

[0027] Figure 4 4 is a color difference line diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0028] A vehicle-mounted front view lens, see Figure 1 : It includes, along the optical axis from the object side to the image side, a first lens 1, a second lens 2, a third lens 4, a fourth lens 5, a fifth lens 6, a sixth lens 7, a parallel plate 8, and an image plane IMA9;

[0029] The first lens 1 has positive power, is specifically a first meniscus positive lens, and its object side surface is concave;

[0030] The second lens 2 has positive power and is specifically a second meniscus positive lens, whose object side surface is convex and image side surface is concave;

[0031] The third lens 4 has negative optical power, and is specifically a third biconcave negative lens, whose object side surface is concave and image side surface is concave;

[0032] The fourth lens 5 has positive refractive power, and its object side surface is convex;

[0033] The fifth lens 6 has positive refractive power, and its object side surface is convex and its image side surface is convex;

[0034] The sixth lens element 7 has negative power, and its object side surface is concave and its image side surface is concave.

[0035] The image side surface S2 of the first lens 1 is a concave surface or a convex surface;

[0036] The fifth lens 6 and the sixth lens 7 are combined to form a cemented lens;

[0037] The fifth lens 6 and the sixth lens 7 are separate lenses;

[0038] The image side surface of the fourth lens 5 is concave or convex;

[0039] The difference between the beta numbers V1 and V2 of at least two adjacent lenses among the six lenses satisfies: 10<|V1-V2|<40;

[0040] BFL is the distance from the center of the image side surface of the sixth lens 7 to the imaging surface of the optical lens on the optical axis, TTL is the distance from the center of the object side surface of the first lens 1 to the imaging surface of the optical lens on the optical axis, and the entire lens satisfies the condition: BFL / TTL≤0.3;

[0041] FOV is the maximum field of view of the optical lens, D is the maximum aperture of the object side of the first lens 1 corresponding to the maximum field of view of the optical lens, h is the half image height corresponding to the maximum field of view of the optical lens, and the entire lens meets the condition: FOV / h / D≤0.65;

[0042] The maximum field of view angle FOV of the optical lens, the focal length value F of the entire set of the optical lens, and the half image height h corresponding to the maximum field of view angle of the optical lens satisfy the following conditions: (FOV×F) / h≥55;

[0043] The entire lens meets the following conditions: TTL / F≤2;

[0044] f1, f2, f3, f4, f5, f6 are the focal lengths of the first to sixth lenses respectively, and the entire lens satisfies the conditions: 2≤f1 / F≤infinity, 0.3≤f2 / F≤5, -20≤f3 / F≤-0.4, -0.2≤f4 / F≤1.5, -0.5≤f5 / F≤0.8, -3≤f6 / F≤0.

[0045] In a specific embodiment, the parameters of each lens are shown in Table 1:

[0046] Table 1

[0047]

[0048]

[0049] Table 1

[0050] In Table 1, when the curvature radius of the aperture 3, the parallel plate 8 and the image plane IMA 9 is Infinity, it means that the surface is a plane.

[0051] The aperture 3 is placed between the second lens 2 and the third lens 4. The fifth lens 6 and the sixth lens 7 are combined to form a cemented lens, and the surface formed by the cementation is S11. The image side of the cemented combined lens is sequentially arranged with a parallel plate 8 and an image plane IMA9. The parallel plate 8 is specifically a protective glass.

[0052] In a specific embodiment, the ratios of various parameters of the lens are shown in Table 2:

[0053] project TTL / F FOV×F / h FOV / h / D BFL / TTL scope ≤2 ≥55 ≤0.65 ≤0.3

[0054] Table 2

[0055] It uses six lenses, the first lens has positive focal power, specifically the first meniscus positive lens, and its object side is concave, the second lens has positive focal power, specifically the second meniscus positive lens, its object side is convex, and the image side is concave, the third lens has negative focal power, specifically the third double concave negative lens, its object side is concave, and the image side is concave. The six glass spherical lenses are combined to form an overall lens, which has a simple structure and a small size. It can achieve clear imaging in the range of -40° to 125°, has small temperature drift, meets the 2-megapixel imaging requirements, has a large aperture, and can shoot a field of view of 38°.

[0056] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0057] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A vehicle-mounted front view lens, characterized in that: It includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a parallel plate, and an image plane IMA in sequence from the object side to the image side along the optical axis; The first lens has positive optical power, and is specifically a first meniscus positive lens, and its object side surface is convex; The second lens has positive power and is specifically a second meniscus positive lens, the object side surface of which is convex and the image side surface is concave; The third lens has negative optical power, and is specifically a third biconcave negative lens, whose object side surface is concave and image side surface is concave; The fourth lens has positive refractive power, and its object side surface is convex; The fifth lens has positive refractive power, and its object side surface is convex, and its image side surface is convex; The sixth lens has negative optical power, and its object side surface is concave, and its image side surface is concave; The image side surface of the first lens is a concave surface; The fifth lens and the sixth lens are combined to form a cemented lens or a separated lens; BFL is the distance from the center of the image side surface of the sixth lens to the imaging surface of the lens on the optical axis, TTL is the distance from the center of the object side surface of the first lens to the imaging surface of the lens on the optical axis, and the entire lens satisfies the condition: BFL / TTL≤0.3; FOV is the maximum field of view of the lens, D is the maximum aperture of the object side of the first lens corresponding to the maximum field of view of the lens, h is the half image height corresponding to the maximum field of view of the lens, and the entire lens meets the condition: FOV / h / D≤0.

65.

2. The vehicle-mounted front view lens according to claim 1, characterized in that: The image side surface of the fourth lens is concave or convex.

3. The vehicle-mounted front view lens according to claim 1, characterized in that: The difference between the bezel numbers V1 and V2 of at least two adjacent lenses among the six lenses satisfies: 10<|V1-V2|<40.

4. The vehicle-mounted front view lens according to claim 1, characterized in that: The maximum field of view angle FOV of the lens, the entire focal length value F of the lens and the half image height h corresponding to the maximum field of view angle of the lens satisfy the following: (FOV×F) / h≥55.

5. The vehicle-mounted front view lens according to claim 4, characterized in that: The entire lens meets the condition: TTL / F≤2.

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