A six-piece side-view camera and imaging method thereof

Abstract

The present application relates to a kind of six-piece side rear view camera, the optical system of the camera is by first lens, second lens, third lens, diaphragm, fourth lens, fifth lens and sixth lens are sequentially arranged from left to right along the light path of light incidence;In the case of not considering the inflection caused by aspherical coefficient, first lens is double-concave negative lens;Second lens is flat convex positive lens;Third lens is double-concave negative lens;Fourth lens is double-convex positive lens;Fifth lens is double-convex positive lens;Sixth lens is meniscus concave negative lens;The first lens, second lens, third lens, fourth lens, fifth lens are all glass spherical lens, and sixth lens is glass aspherical lens.The lens of object is greater than 80 degrees, and simultaneously has the advantages such as high resolution, large light aperture, lower tolerance sensitivity and better high-low temperature stability, etc., can more comprehensively monitor the scene of car side and far place.

Description

Technical Field

[0001] This invention relates to a six-element side-rear view camera and its imaging method, and relates to the field of lens technology. Background Technology

[0002] With the development of automotive safety technology, in-vehicle vision systems have gradually become an important component of automotive electronic systems. To achieve the goal of safe driving, in-vehicle vision systems centered around camera modules are being installed in various parts of the vehicle. For example, installing a system on the front side of the A-pillar can effectively reduce blind spots on both sides of the front of the vehicle, while installing one under the trunk can effectively reduce blind spots on the rear side when reversing. Side-view cameras have emerged in this context. They are typically installed on the front fender of the vehicle, with a field of view of approximately 90° and a detection distance of about 80 meters. They are mainly used for scenarios such as lane changes and merging into other roads. The market is constantly pursuing higher pixel density and longer detection distances, as these mean higher accuracy and practicality. However, this often leads to an increase in the number of lenses, which is not conducive to market penetration. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the technical problem to be solved by the present invention is to provide a six-element side-rear view camera and its imaging method, which achieves high-resolution and clear imaging while having fewer elements and a smaller overall size.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is: a six-element side-rear-view camera, wherein the 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, and a sixth lens arranged sequentially from left to right along the incident light path; without considering the curvature caused by the aspherical coefficient, the first lens is a biconcave negative lens with a concave object side and a concave image side; the second lens is a plano-convex positive lens with a convex object side and a planar image side; the third lens is a biconcave negative lens with a concave object side and a concave image side; the fourth lens is a biconvex positive lens with a convex object side and a convex image side; the fifth lens is a biconvex positive lens with a convex object side and a convex image side; the sixth lens is a meniscus negative lens with a convex object side and a concave image side; the first, second, third, fourth, and fifth lenses are all glass spherical lenses, and the sixth lens is a glass aspherical lens.

[0005] Preferably, the focal length of the optical system is set to f, and the focal lengths of the first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens are f1, f2, f3, f4, f5, and f6, respectively, wherein f1, f2, f3, f4, f5, and f6 satisfy the following ratio with f: -2.0 <f1 / f<-1.0,2.0<f2 / f<3.0,-2.0<f3 / f<-1.0,1.0<f4 / f<2.0,1.0<f5 / f<2.0,-6.0<f6 / f<-5.0。

[0006] Preferably, the first lens satisfies the relationship: 1.4 ≤ N d ≤1.7, 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: 1.6≤N d ≤1.9, 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: 1.5≤N d ≤1.8, V d ≤50.0; where N d V is the refractive index. d Let be Abbe's constant.

[0007] Preferably, the on-axis distances between the lenses satisfy the following relationships: the air gap between the first lens and the second lens is 1.5 to 2.0 mm; the air gap between the second lens and the third lens is 1.0 to 1.5 mm; the air gap between the third lens and the aperture stop is 0.0 to 0.5 mm; the air gap between the aperture stop and the fourth lens is 0.0 to 0.5 mm; the air gap between the fourth lens and the fifth lens is 0.0 to 0.5 mm; and the air gap between the fifth lens and the sixth lens is 0.0 to 0.5 mm.

[0008] Preferably, the equation for the aspherical curve of the sixth lens is as follows:

[0009]

[0010] Where z is the distance from the vertex of the aspherical surface to the optical axis at a position of height r; c is the paraxial curvature of the aspherical surface, r = 1 / c; k is the conic constant; α1, α2, α3, α4, α5, α6, α7, and α8 are all higher-order coefficients.

[0011] Preferably, the total optical length (TTL) of the optical system and the focal length (f) of the optical system satisfy the following condition: TTL / f ≤ 6.0.

[0012] Preferably, the F-number of the optical system is ≤1.6.

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

[0014] Preferably, a filter is provided on the rear side of the sixth lens.

[0015] An imaging method for a six-element side-rear view camera is performed according to the following steps: light passes sequentially through a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, and a sixth lens before forming an image.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. This lens has an imaging angle of more than 80 degrees and features high resolution, large aperture, low tolerance sensitivity and good high and low temperature stability. It can also monitor the side and rear of the vehicle and distant scenes more comprehensively.

[0018] 2. By rationally matching the various optical lenses, the system structure is compact and reasonable, easy to assemble, has low tolerance sensitivity, and is more suitable for large-scale high-yield production;

[0019] 3. It adopts an all-glass structure, which has high stability and can compensate for focal plane displacement at high and low temperatures, and has the adaptability to complex environments;

[0020] 4. Corrected chromatic aberration along each axis, transverse chromatic aberration, and higher-order chromatic aberrations to ensure high imaging quality even at large angles;

[0021] 5. Fully leverage the advantages of aspherical lenses in correcting aberrations, achieving high-definition imaging while featuring a smaller lens outer diameter and shorter overall optical length, ensuring lens miniaturization.

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the optical structure of the present invention;

[0024] Figure 2 This is the axial chromatic aberration diagram of the entire working band of the present invention;

[0025] Figure 3 This is the transverse chromatic aberration diagram of the entire working band of the present invention;

[0026] Figure 4 This is the field curvature distortion diagram of the entire working band of the present invention;

[0027] In the diagram: first lens L1, second lens L2, third lens L3, aperture STO, fourth lens L4, fifth lens L5, sixth lens L6, first equivalent glass plate L7, second equivalent glass plate L8, image plane IMA. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0029] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0030] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0031] like Figures 1-4 As shown, this embodiment provides a six-element side-rear-view camera. The optical system of the camera consists of a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, and a sixth lens arranged sequentially from left to right along the incident light path. Without considering the curvature caused by the aspherical coefficient, the first lens is a biconcave negative lens with a concave object-side surface and a concave image-side surface; the second lens is a plano-convex positive lens with a convex object-side surface and a planar image-side surface; the third lens is a biconcave negative lens with a concave object-side surface and a concave 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 biconvex positive lens with a convex object-side surface and a convex image-side surface; and the sixth lens is a meniscus negative lens with a convex object-side surface and a concave image-side surface. The first, second, third, fourth, and fifth lenses are all spherical glass lenses, and the sixth lens is a glass aspherical lens.

[0032] The appropriate lens combination enables the optical system to achieve a small size, large aperture, confocal day and night operation, and low temperature drift design. Simultaneously, it effectively corrects on-axis and off-axis aberrations, resulting in good image quality. Figures 2 to 4 As shown.

[0033] In this embodiment of the invention, the focal length of the optical system is set to f, and the focal lengths of the first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens are f1, f2, f3, f4, f5, and f6, respectively, wherein f1, f2, f3, f4, f5, and f6 satisfy the following ratio with f: -2.0 <f1 / f<-1.0,2.0<f2 / f<3.0,-2.0<f3 / f<-1.0,1.0<f4 / f<2.0,1.0<f5 / f<2.0,-6.0<f6 / f<-5.0。

[0034] In this embodiment of the invention, the first lens satisfies the relationship: 1.4 ≤ N d ≤1.7, 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: 1.6≤N d ≤1.9, 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: 1.5≤N d ≤1.8, V d ≤50.0; where N d V is the refractive index. d Let be Abbe's constant.

[0035] In this embodiment of the invention, the on-axis distances between the lenses satisfy the following relationships: the air gap between the first lens and the second lens is 1.5 to 2.0 mm; the air gap between the second lens and the third lens is 1.0 to 1.5 mm; the air gap between the third lens and the aperture stop is 0.0 to 0.5 mm; the air gap between the aperture stop and the fourth lens is 0.0 to 0.5 mm; the air gap between the fourth lens and the fifth lens is 0.0 to 0.5 mm; and the air gap between the fifth lens and the sixth lens is 0.0 to 0.5 mm.

[0036] In this embodiment of the invention, the equation for the aspherical curve of the sixth lens is expressed as follows:

[0037]

[0038] Where z is the distance from the vertex of the aspherical surface to the optical axis at a position of height r; c is the paraxial curvature of the aspherical surface, r = 1 / c; k is the conic constant; α1, α2, α3, α4, α5, α6, α7, and α8 are all higher-order coefficients.

[0039] In this embodiment of the invention, the total optical length (TTL) of the optical system and the focal length (f) of the optical system satisfy the following condition: TTL / f ≤ 6.0.

[0040] In this embodiment of the invention, the F-number of the optical system is ≤1.6.

[0041] In this embodiment of the invention, the image height H of the optical system and the focal length f of the optical system satisfy the following condition: H / f≤1.0.

[0042] In this embodiment of the invention, a filter is provided on the rear side of the sixth lens.

[0043] An imaging method for a six-element side-rear view camera is performed according to the following steps: light passes sequentially through a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, and a sixth lens before forming an image.

[0044] In this embodiment of the invention, the technical specifications achieved by the optical system are as follows:

[0045] (1) Focal length: 5.0≤EFFL≤6.0mm;

[0046] (2) Aperture F≤1.6;

[0047] (3) Field of view: 2w ≥ 80°;

[0048] (4) Operating band: Visible light band.

[0049] To achieve the above design parameters, the specific design of the optical system adopted in this embodiment is shown in the table below:

[0050]

[0051]

[0052] The aspherical coefficients of the aspherical lenses in the optical system of this embodiment are shown in the table below:

[0053]

[0054] The optical system in this embodiment achieves miniaturization of the lens assembly by rationally allocating the optical power, surface shape, center thickness of each lens, and on-axis distance between each lens, while meeting the lens imaging performance requirements.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A six-element side-rear view camera, characterized in that: The optical system of the camera consists of a first lens, a second lens, a third lens, an aperture stop, a fourth lens, a fifth lens, and a sixth lens arranged sequentially from left to right along the incident light path. Without considering the curvature caused by aspherical coefficients, the first lens is a biconcave negative lens with both its object-side and image-side surfaces concave; the second lens is a plano-convex positive lens with both its object-side and image-side surfaces flat; the third lens is a biconcave negative lens with both its object-side and image-side surfaces concave; the fourth lens is a biconvex positive lens with both its object-side and image-side surfaces convex; the fifth lens is a biconvex positive lens with both its object-side and image-side surfaces convex; and the sixth lens is a meniscus negative lens with both its object-side and image-side surfaces concave. The first, second, third, fourth, and fifth lenses are all spherical glass lenses, and the sixth lens is a glass aspherical lens. The focal length of the optical system is set to... The focal lengths of the first lens, second lens, third lens, fourth lens, fifth lens, and sixth lens are respectively , , , , , ,in , , , , , and Meets the following ratio: -2.0 < / <-1.0, 2.0< / <3.0, -2.0< / <-1.0, 1.0< / <2.0, 1.0< / <2.0, -6.0< / <-5.

0.

2. The six-piece side-rear view camera according to claim 1, characterized in that: The first lens satisfies the relation: 1.4 ≤ ≤1.7, ≥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 relation: 1.6≤ ≤1.9, ≥50.0; The fifth lens satisfies the relationship: 1.5≤ ≤1.8, ≥50.0; The sixth lens satisfies the relationship: 1.5≤ ≤1.8, ≤50.0; where For refractive index, Let be Abbe's constant.

3. The six-piece side-rear view camera according to claim 1, characterized in that: The on-axis distances between the lenses satisfy the following relationships: 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 1.0~1.5mm; the air gap between the third lens and the aperture stop is 0.0~0.5mm; the air gap between the aperture stop and the fourth lens is 0.0~0.5mm; the air gap between the fourth lens and the fifth lens is 0.0~0.5mm; and the air gap between the fifth lens and the sixth lens is 0.0~0.5mm.

4. The six-piece side-rear view camera according to claim 1, characterized in that: The equation for the aspherical curve of the sixth lens is: Where z is the distance from the vertex of the aspherical surface to the optical axis at a position of height r; c is the paraxial curvature of the aspherical surface, r = 1 / c; and k is the conic constant. , , , , , , , All are coefficients of higher-order terms.

5. The six-piece side-rear view camera according to claim 1, characterized in that: The total optical length (TTL) of an optical system and the focal length (f) of the optical system satisfy the following condition: TTL / f ≤ 6.

0.

6. The six-piece side-rear view camera according to claim 1, characterized in that: The F-number of the optical system is ≤1.

6.

7. The six-piece side-rear view 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 the following condition: H / f≤1.

0.

8. The six-piece side-rear view camera according to claim 1, characterized in that: A filter is provided on the rear side of the sixth lens.

9. An imaging method for a six-element side-rear-view camera as described in any one of claims 1-8, characterized in that, The following steps are performed: light rays pass sequentially through the first lens, the second lens, the third lens, the aperture stop, the fourth lens, the fifth lens, and the sixth lens to form an image.

Images