Wide-angle high-resolution vehicle-mounted front-view lens and imaging method

Abstract

The invention relates to a wide-angle high-resolution vehicle-mounted front-view lens, an optical system of the lens is composed of a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged from left to right along a light incident light path, and a diaphragm is arranged between the third lens and the fourth lens. Wherein the first lens, the second lens, the third lens, the fourth lens and the fifth lens are glass spherical lenses, and the sixth lens is a glass aspheric lens. The imaging field angle of the optical system is larger than 135 degrees, the clear aperture is large, the imaging definition is high, axial, vertical and high-order chromatic aberration is effectively corrected, and the edge imaging quality under the large field angle is ensured. In addition, the system is compact and reasonable in structure, has low tolerance sensitivity and good high and low temperature stability, and has mass production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lenses, in particular to a wide-angle high-resolution vehicle-mounted front-view lens and an imaging method. BACKGROUND

[0002] With the development of automatic driving technology of vehicles, the technical requirements of the system for vehicle-mounted cameras continue to improve. As a core component of the automatic driving system, the vehicle-mounted front-view lens is responsible for collecting the road conditions in front, but the traditional products have obvious shortcomings: low image resolution, small depth of field range, insufficient aperture specification, difficult to capture the details of distant objects while meeting the demand for large field of view, unable to accurately monitor the surrounding environment of the vehicle in real time, and there is a risk of driving, and the use of multiple glass aspherical lenses has high production cost. SUMMARY

[0003] In view of the shortcomings of the prior art, the technical problem to be solved by the present application is to provide a wide-angle high-resolution vehicle-mounted front-view lens with the advantages of large field of view, large aperture, high resolution and low production cost.

[0004] In order to solve the above technical problems, the technical scheme of the present application is: a wide-angle high-resolution vehicle-mounted front-view lens, the optical system of the lens is composed of a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged in order from left to right along the light incident path, and a diaphragm is arranged between the third lens and the fourth lens; without considering the reverse curvature caused by the aspherical coefficient, the first lens is a meniscus negative lens, the object side is convex, and the image side is concave; the second lens is a double-concave negative lens, the object side is concave, and the image side is concave; the third lens is a double-convex positive lens, the object side is convex, and the image side is convex; the fourth lens is a double-convex positive lens, the object side is convex, and the image side is convex; the fifth lens is a meniscus negative lens, the object side is concave, and the image side is convex; the sixth lens is a double-convex positive lens, the object side is convex, and the image side is convex; the lens is made of glass material, wherein the first lens, the second lens, the third lens, the fourth lens and the fifth lens are glass spherical lenses, the sixth lens is a glass aspherical lens, and the fourth lens and the fifth lens are cemented lens groups.

[0005] Preferably, 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 and the sixth lens are f1, f2, f3, f4, f5 and f6 respectively, wherein f1, f2, f3, f4, f5 and f6 satisfy the following proportions: -2.0

[0006] Preferably, the first lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≥50.0; the second lens satisfies the relationship: 1.4≤N d ≤1.7, V d ≥50.0; the third lens satisfies the relationship: 1.8≤N d ≤2.1, V d ≤50.0; the fourth lens satisfies the relationship: 1.5≤N d ≤1.8, 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: 1.6≤N d ≤1.9, V d ≤50.0; wherein N d is the refractive index, and V d is the Abbe number.

[0007] Preferably, the axial distance between each lens satisfies the following relationship: the air gap between the first lens and the second lens is 3.0-3.5mm; the air gap between the second lens and the third lens is 1.5-2.0mm; the air gap between the third lens and the diaphragm is 1.0-1.5mm; the air gap between the diaphragm and the fourth lens is 0.0-0.5mm; the fourth lens and the fifth lens are a cemented lens group, and the air gap is 0mm; the air gap between the fifth lens and the sixth lens is 1.5-2.0mm.

[0008] Preferably, the sixth lens is an aspherical lens. The aspherical curve equation is expressed as:

[0009]

[0010] wherein z is the sagittal height of the aspherical surface at 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.

[0011] Preferably, the total optical length TTL of the optical system and the focal length f of the optical system satisfy the relationship: TTL / f≤7.0.

[0012] Preferably, the F number of the optical system is ≤1.9.

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

[0014] Preferably, the diaphragm of the optical system is located between the third lens and the fourth lens.

[0015] Preferably, the image side of the sixth lens is provided with a filter.

[0016] An imaging method for a wide-angle, high-resolution vehicle-mounted front-view lens comprises the following steps: light rays pass sequentially from left to right through a first lens, a second lens, a third lens, an aperture stop, a fourth lens, a fifth lens, and a sixth lens before forming an image on the imaging plane.

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

[0018] This invention provides a wide-angle, high-resolution automotive forward-looking lens employing six optical elements, consisting of five spherical glass lenses and one aspherical glass lens forming the imaging system. This optical system utilizes a large aperture and all-glass lens design, increasing light intake while achieving a wide field of view and low temperature drift, ensuring clear imaging even in low-light and complex road conditions. By appropriately selecting glass materials, the system effectively corrects various aberrations, guaranteeing consistent image quality across the entire field of view. Compared to aspherical lenses, the spherical design offers a cost advantage while maintaining high performance, and is easier to assemble with more lenient tolerances, making it suitable for large-scale, high-yield production.

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0020] Fig. 1 This is a schematic diagram of the optical structure according to an embodiment of the present invention;

[0021] Fig. 2 This is an axial chromatic aberration diagram of the entire working band of this invention.

[0022] Fig. 3 This is a cross-axis chromatic aberration diagram for the entire working band of this invention.

[0023] Fig. 4 This is a field curvature distortion diagram for the entire working band of this invention.

[0024] In the diagram: STO - aperture stop; L1 - first lens; L2 - second lens; L3 - third lens; L4 - fourth lens; L5 - fifth lens; L6 - sixth lens; L7 - first equivalent glass plate; L8 - second equivalent glass plate; IMA - imaging plane. Detailed Implementation

[0025] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings for detailed explanation.

[0026] like Figs. 1-4As shown, a wide-angle, high-resolution automotive front-view lens comprises, from object to image, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens, with an aperture stop located between the third and fourth lenses. The first, second, third, fourth, and fifth lenses are spherical glass lenses, and the sixth lens is an aspherical glass lens. The first and second lenses are both lenses with negative optical power, which can pre-correct aberrations while adjusting for large-angle light. The aperture stop is placed at the center of the system, and its symmetrical structure and aspherical glass lens reduce optical distortion. The fourth and fifth lenses form an achromatic cemented doublet. This reasonable lens arrangement enables the optical system to achieve a compact size, large field of view, large aperture, and low temperature drift design, while effectively correcting on-axis and off-axis aberrations, resulting in good image quality. Figs. 2 to 4 As shown.

[0027] The technical specifications achieved by the optical system in this embodiment are as follows:

[0028] (1) Focal length: 3.0≤EFFL≤4.0mm;

[0029] (2) Aperture F≤1.9;

[0030] (3) Field of view: 2w ≥ 135°;

[0031] (4) Operating band: Visible light band.

[0032] To achieve the above design parameters, the specific design of the optical system adopted in this embodiment is shown in the table below:

[0033]

[0034]

[0035] The aspherical coefficients of the aspherical lenses in the optical system of this embodiment are shown in the table below:

[0036]

[0037] The optical system in this embodiment achieves advantages such as high resolution, large aperture, high resolution, large field of view, and low production cost by rationally allocating the optical power, surface shape, center thickness of each lens, and on-axis distance between each lens.

[0038] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present 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 wide-angle high-resolution vehicle-mounted front-view lens comprising an optical system, characterized in that: The optical system of the lens is composed of a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens and a sixth lens arranged in sequence from left to right along the light path of the incident light, wherein, without considering the reverse bending caused by the aspherical surface coefficient, the first lens is a meniscus negative lens; the second lens is a double-concave negative lens; the third lens is a double-convex positive lens; the fourth lens is a double-convex positive lens; the fifth lens is a meniscus negative lens; and the sixth lens is a double-convex positive lens.

2. The wide-angle high-resolution vehicle-mounted front-view lens according to claim 1, characterized in that: The object side surface of the first lens is a convex surface, and the image side surface is a concave surface; the object side surface of the second lens is a concave surface, and the image side surface is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface is a convex surface; the object side surface of the fourth lens is a convex surface, and the image side surface is a convex surface; the object side surface of the fifth lens is a concave surface, and the image side surface is a convex surface; and the object side surface of the sixth lens is a convex surface, and the image side surface is a convex surface.

3. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: 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 and the sixth lens are f1, f2, f3, f4, f5 and f6 respectively, wherein f1, f2, f3, f4, f5 and f6 satisfy the following ratios: -2.0 < f1 / f < -1.0, -3.0 < f2 / f < -2.0, 1.0 < f3 / f < 2.0, 1.0 < f4 / f < 2.0, -2.0 < f5 / f < -1.0 and 2.0 < f6 / f < 3.

0.

4. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: The first lens satisfies the relationship: 1.7≤N d ≤2.0, V d ≤50.0; the second lens satisfies the relationship: 1.4≤N d ≤1.7, V d ≥50.0; the third lens satisfies the relation: 1.8≤N d ≤2.1, V d ≤50.0; the fourth lens satisfies the relation: 1.5≤N d ≤1.8, V d ≥50.0; the fifth lens satisfies the relation: 1.7≤N d ≤2.0, V d ≤50.0; the sixth lens satisfies the relationship: 1.6≤N d ≤1.9, V d ≤50.0; where N d is the refractive index, V d is the Abbe number.

5. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: The air gap between the first lens and the second lens is 3.0-3.5 mm; the air gap between the second lens and the third lens is 1.5-2.0 mm; the air gap between the third lens and the diaphragm is 1.0-1.5 mm; the air gap between the diaphragm and the fourth lens is 0.0-0.5 mm; the fourth lens and the fifth lens are a cemented lens group, and the air gap is 0 mm; and the air gap between the fifth lens and the sixth lens is 1.5-2.0 mm. The sixth lens is an aspherical lens. The aspherical curve equation expression is as follows:

6. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: wherein z is the sagittal height of the aspherical surface at a height of r along the optical axis; 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. The optical total length TTL of the optical system and the focal length f of the optical system satisfy the following relationship:

7. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: TTL / f ≤ 7.

0. The F number of the optical system is ≤1.

9.

8. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: The image height H of the optical system and the focal length f of the optical system satisfy the following relationship:

9. The wide-angle, high-resolution, vehicle-mounted front-view lens of claim 1, wherein: The light is sequentially imaged on the imaging plane through the first lens, the second lens, the third lens, the diaphragm, the fourth lens, the fifth lens and the sixth lens from left to right.

10. An imaging method applied to the wide-angle high-resolution vehicle-mounted front-view lens of claim 2, characterized in that, ​

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