3M five-piece type foresight main camera

Abstract

The utility model relates to a 3M five-piece type foresight main camera. The 3M five-piece type foresight main camera comprises a first lens, a second lens, a diaphragm, a third lens, a fourth lens and a fifth lens which are sequentially arranged from left to right along a light incident light path, the first lens is a meniscus negative lens, the object side surface of the first lens is a convex surface, and the image side surface is a concave surface; the second lens is a biconvex positive lens, the object side surface is a convex surface, and the image side surface is a convex surface; the third lens is a biconvex positive lens, the object side surface is a convex surface, and the image side surface is a convex surface; the fourth lens is a biconcave negative lens, the object side surface is a concave surface, and the image side surface is a concave surface; the fifth lens is a biconvex positive lens, and has a convex object-side surface and a convex image-side surface. According to the utility model, the design is reasonable, the structure is simple, through reasonable distribution of 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 3M imaging performance requirement of the five-piece lens is satisfied, the total length of the lens and the radial size of each lens are reduced, and the miniaturization of the lens group is realized.

Description

Technical Field

[0001] The utility model relates to a 3M five-piece front-view main camera. Background Art

[0002] At present, the on-board cameras installed in the car are mainly divided into five categories according to the installation position: front view camera, surround view camera, rear view camera, side view camera and built-in camera. Front view camera: Mainly installed on the front windshield, used to realize the visual perception and recognition function of driving. According to the function, it can be divided into front view main camera, front view narrow angle camera and front view wide angle camera. Front view main camera: This camera is used as the main camera in the L2 ADAS system. Its field of view angle is generally 30°, 50°, 60°, 100°, 120°, and the detection distance is generally 150~170m, which plays the L2 level functions such as road condition monitoring and lane departure warning. Under this premise, higher pixel density and longer detection distance mean higher accuracy and practicality, which often increases the number of lenses. The market mostly adopts seven or more structures for design, which is not conducive to cost reduction and lens promotion. Utility Model Content

[0003] The utility model improves the above-mentioned problem, that is, the technical problem to be solved by the utility model is to provide a 3M five-piece front-view main camera, which has a smaller external size while achieving clear imaging of five 3M pieces.

[0004] The utility model is constructed as follows: it comprises a first lens, a second lens, an aperture, a third lens, a fourth lens and a fifth lens which are arranged in sequence from left to right along the incident optical path of light; the first lens is a meniscus negative lens, whose object side surface is a convex surface, and whose image side surface is a concave surface; the second lens is a biconvex positive lens, whose object side surface is a convex surface, and whose image side surface is a convex surface; the third lens is a biconvex positive lens, whose object side surface is a convex surface, and whose image side surface is a convex surface; the fourth lens is a biconcave negative lens, whose object side surface is a concave surface, and whose image side surface is a concave surface; the fifth lens is a biconvex positive lens, whose object side surface is a convex surface, and whose image side surface is a convex surface.

[0005] Furthermore, 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, and the fifth lens are f1, f2, f3, f4, f5, respectively. 5， Among them, f1, f2, f3, f4, f5 and f satisfy the following ratio: -2.0 <f1 / f<-1.0,1.0<f2 / f<2.0,1.0<f3 / f<2.0,-1.0<f4 / f<0.0,1.0<f5 / f<2.0。

[0006] Furthermore, the first lens satisfies the relationship: 1.5≤N d ≤1.8, Vd ≤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: 1.8≤N d ≤2.0, V d ≤50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; where N d is the refractive index, V d is the Abbe constant.

[0007] Furthermore, the air gap between the first lens and the second lens is 6.0~6.5mm; the aperture is located on the second lens, and the air gap between the aperture and the third lens is 0.5~1.0mm; the third lens and the fourth lens are a cemented lens group, and the air gap is 0 mm; the air gap between the fourth lens and the fifth lens is 0.1~0.5mm.

[0008] Furthermore, the first lens and the fifth lens are aspherical lenses, and the aspherical curve equation is expressed as:

[0009] ;

[0010] 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.

[0011] Furthermore, the total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤5.0.

[0012] Furthermore, a first equivalent glass plate, a second equivalent glass plate and an imaging surface are sequentially arranged on the rear side of the fifth lens.

[0013] Furthermore, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≤1.0.

[0014] Furthermore, the F number of the optical system is ≤1.6.

[0015] Compared with the prior art, the utility model has the following beneficial effects:

[0016] 1. The imaging angle of the lens to the object is greater than 80 degrees. It has the advantages of 3M imaging clarity, large aperture, low tolerance sensitivity and good high and low temperature stability. At the same time, it can more comprehensively monitor the scene in front of the vehicle and in the distance; 2. By reasonably matching various optical lenses, the system structure is five pieces, while ensuring compactness and rationality, easy assembly, low tolerance sensitivity, and more suitable for large-scale high-yield production; 3. The all-glass structure has high stability, can make good compensation for focal plane displacement at high and low temperatures, and has adaptability to complex environments; 4. The axial chromatic aberration, vertical axis chromatic aberration and high-order chromatic aberration are corrected to ensure that the imaging system can have high imaging quality at large angles. 5. Give full play to the advantages of aspheric surfaces, while reducing aberrations, further reduce the number of pieces and shorten the lens length. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the optical structure of an embodiment of the utility model;

[0018] Figure 2 This is the axial chromatic aberration diagram of the full working band of the embodiment of the utility model;

[0019] Figure 3 This is a vertical axis chromatic aberration diagram of the entire working band of the embodiment of the utility model;

[0020] Figure 4 This is a field curvature distortion diagram of the full working band of the embodiment of the utility model;

[0021] In the figure: L1-first lens; L2-second lens; L3-third lens; STO-aperture; L4-fourth lens; L5-fifth lens; L6-first equivalent glass plate; L7-second equivalent glass plate; IMA-imaging surface. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0023] Example: Figures 1 to 4As shown, the utility model provides a 3M five-piece front-view main camera, including a first lens L1, a second lens L2, an aperture STO, a third lens L3, a fourth lens L4 and a fifth lens L5 arranged in sequence from left to right along the incident light path of the light; the above-mentioned first lens and fifth lens are aspherical lenses, and the second lens, the third lens and the fourth lens are all glass spherical lenses; the lenses are made of glass materials, wherein the first lens has a lens with negative optical focal length, which, as an aspherical lens, has the function of reducing aberrations such as optical system distortion while adjusting large-angle light. The third lens and the fourth lens form an achromatic double cemented lens. Through reasonable lens matching, the optical system can achieve a small volume, 3M, large aperture, day and night confocal, and low-temperature drift design through a five-piece structure, and at the same time, the on-axis and off-axis aberrations are well corrected, with good imaging quality.

[0024] Without considering the backcurvature 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 biconvex positive lens, whose object side surface is convex 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 biconcave negative lens, whose object side surface is concave and whose image side surface is concave; the fifth lens is a biconvex positive lens, whose object side surface is convex and whose image side surface is convex.

[0025] In the embodiment of the utility model, 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, and the fifth lens are f1, f2, f3, f4, and f5, respectively. 5， Among them, f1, f2, f3, f4, f5 and f satisfy the following ratio: -2.0 <f1 / f<-1.0,1.0<f2 / f<2.0,1.0<f3 / f<2.0,-1.0<f4 / f<0.0,1.0<f5 / f<2.0。

[0026] In the embodiment of the utility model, the first lens satisfies the relationship: 1.5≤N d ≤1.8, 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: 1.8≤N d ≤2.0, V d ≤50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; where N d is the refractive index, V dis the Abbe constant.

[0027] In an embodiment of the utility model, the air gap between the first lens and the second lens is 6.0-6.5 mm; the aperture is located on the second lens, and the air gap between the aperture and the third lens is 0.5-1.0 mm; the third lens and the fourth lens are a cemented lens group, and the air gap is 0 mm; the air gap between the fourth lens and the fifth lens is 0.1-0.5 mm.

[0028] In the embodiment of the utility model, the first lens and the fifth lens are aspherical lenses, and the aspherical curve equation is expressed as:

[0029] ;

[0030] 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.

[0031] In the embodiment of the utility model, the total optical length TTL of the optical system and the focal length f of the optical system satisfy: TTL / f≤5.0.

[0032] In the embodiment of the utility model, a first equivalent glass plate L6, a second equivalent glass plate L7 and an imaging surface IMA are sequentially arranged on the rear side of the fifth lens.

[0033] In the embodiment of the utility model, the image height H of the optical system and the focal length f of the optical system satisfy: H / f≤1.0.

[0034] In the embodiment of the utility model, the F number of the optical system is ≤1.6.

[0035] The technical indicators achieved by the optical system of the embodiment of the utility model are as follows: (1) focal length: 6.0≤EFFL≤7.0mm; (2) aperture F≤1.6; (3) field of view: 2w≥80°; (4) working band: visible light band.

[0036] To achieve the above design parameters, the specific design parameters of the optical system of the embodiment of the utility model are shown in Table 1 below:

[0037]

[0038] Table 1

[0039] The aspheric coefficients of the aspheric lenses of the optical system of the embodiment of the utility model are as follows in Table 2:

[0040]

[0041] Table 2

[0042] In the embodiment of the utility model, the optical system reduces the total length of the lens and the radial size of each lens by reasonably allocating the optical focal length, surface shape, center thickness of each lens and axial distance between each lens, while meeting the 3M imaging performance requirements of the five-piece lens, thereby miniaturizing the lens group.

[0043] Unless otherwise stated, any technical solution disclosed in the above utility model, if it discloses a numerical range, then the disclosed numerical range is a preferred numerical range. Any technician in the field should understand that the preferred numerical range is only a numerical value with a more obvious technical effect or representative value among many feasible numerical values. Since there are too many numerical values ​​to be exhaustive, the utility model discloses only some numerical values ​​to illustrate the technical solution of the utility model, and the numerical values ​​listed above should not constitute a limitation on the scope of protection of the utility model.

[0044] At the same time, if the above-mentioned utility model discloses or involves components or structural parts that are fixedly connected to each other, then, unless otherwise stated, the fixed connection can be understood as: a detachable fixed connection (for example, connected by bolts or screws), and can also be understood as: a non-detachable fixed connection (for example, riveting, welding). Of course, the mutual fixed connection can also be replaced by an integrated structure (for example, manufactured by one-piece molding using a casting process) (except when it is obviously impossible to use an one-piece molding process).

[0045] If the words "first", "second" and so on are used in this article to limit components, those skilled in the art should know that the use of "first" and "second" is only for the convenience of description to distinguish the components. Unless otherwise stated, the above words have no special meaning.

[0046] In addition, unless otherwise stated, the terms used to indicate positional relationships or shapes in any of the technical solutions disclosed in the above utility model include states or shapes that are approximate, similar or close thereto.

[0047] Any component provided by the utility model can be assembled from multiple separate components, or can be a separate component manufactured by an integrated molding process.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the utility model can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the utility model, which should be included in the scope of the technical solution for protection of the utility model.

Claims

1. A 3M five-piece front-view main camera, characterized in that: It includes a first lens, a second lens, an aperture, a third lens, a fourth lens and a fifth lens which are arranged in sequence from left to right along the incident optical path of the light; 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 biconvex positive lens, whose object side surface is convex 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 biconcave negative lens, whose object side surface is concave and whose image side surface is concave; the fifth lens is a biconvex positive lens, whose object side surface is convex and whose image side surface is convex.

2. The 3M five-piece 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, and the fifth lens are f1, f2, f3, f4, f5, respectively. 5， Among them, f1, f2, f3, f4, f5 and f satisfy the following ratio: -2.0 <f1 / f<-1.0,1.0<f2 / f<2.0,1.0<f3 / f<2.0,-1.0<f4 / f<0.0,1.0<f5 / f<2.0。 3. The 3M five-piece front-view main 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: 1.5≤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: 1.8≤N d ≤2.0, V d ≤50.0; the fifth lens satisfies the relationship: 1.5≤N d ≤1.8, V d ≤50.0; where N d is the refractive index, V d is the Abbe constant.

4. The 3M five-piece front-view main camera according to claim 1, characterized in that: The air interval between the first lens and the second lens is 6.0~6.5mm; the aperture is located on the second lens, and the air interval between the aperture and the third lens is 0.5~1.0mm; the third lens and the fourth lens are a cemented lens group, and the air interval is 0 mm; the air interval between the fourth lens and the fifth lens is 0.1~0.5mm.

5. The 3M five-piece front-view main camera according to claim 1, characterized in that: The first lens and the fifth lens are 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 3M five-piece front-view main 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.

7. The 3M five-piece front-view main camera according to claim 1, characterized in that: The rear side of the fifth lens is provided with a first equivalent glass plate, a second equivalent glass plate and an imaging surface in sequence.

8. The 3M five-piece front-view main 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.

9. The 3M five-piece front-view main camera according to claim 1, characterized in that: The F number of the optical system is ≤1.6.

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