Forward-looking ultra-wide-angle binocular camera

Abstract

The utility model relates to a foresight ultra-wide-angle binocular camera. An 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 and a sixth lens which are sequentially arranged from left to right along a light incident light path. Under the condition that retroflexion caused by aspheric coefficients is not considered, the first lens is a meniscus concave negative lens, the second lens is a meniscus concave positive lens, the third lens is a meniscus convex positive lens, the fourth lens is a biconvex positive lens, the fifth lens is a meniscus concave negative lens, the sixth lens is a meniscus convex positive lens, and all the lenses are made of glass materials. Wherein the first lens and the sixth lens are glass aspheric lenses, and the fourth lens and the fifth lens form a balsaming lens group. While the wide-angle 120-degree clear imaging is realized, the wide-angle 120-degree wide-angle imaging lens has a relatively small appearance size and relatively high environmental stability.

Description

Technical Field

[0001] The utility model relates to a forward-looking ultra-wide-angle binocular camera, and relates to the technical field of lenses. Background Art

[0002] Automobile safety technologies include: lane departure warning, active collision avoidance, adaptive cruise control, traction control, etc. The on-board front-view camera system is an automobile safety technology with lane departure warning function. The on-board front-view camera module plays an important role as the hardware terminal of the system. There are generally two types of on-board front-view camera modules, one is the on-board monocular camera module and the other is the on-board binocular camera module. The on-board monocular camera module solution has a low cost and has a good use effect when used in conjunction with the radar system. However, the binocular camera can complete the 3D stereo recognition function, and has significant advantages in completing target tracking and position prediction. If combined with millimeter-wave radar, it can also detect the target speed. At present, the main problems with the on-board binocular camera module are small field of view, high cost, complex system, and difficulty in product miniaturization. Utility Model Content

[0003] In view of the deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a forward-looking ultra-wide-angle binocular camera.

[0004] In order to solve the above technical problems, the technical solution of the utility model is: a forward-looking ultra-wide-angle binocular camera, 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 in sequence from left to right along the incident light path of the light; without considering the backcurvature caused by the aspheric coefficient, the first lens is a meniscus concave negative lens, the object side surface of which is convex, and the image side surface is concave; the second lens is a meniscus concave positive lens, the object side surface of which is concave, and the image side surface is convex; the third lens is a meniscus convex positive lens, the object side surface of which is convex, and the image side surface is concave; the fourth lens is a double convex positive lens, the object side surface of which is convex, and the image side surface is convex; the fifth lens is a meniscus concave negative lens, the object side surface of which is concave, and the image side surface is convex; the sixth lens is a meniscus convex positive lens, the object side surface of which is convex, and the image side surface is concave; all lenses are made of glass material, wherein the first and sixth lenses are glass aspheric lenses, and the fourth and fifth lenses form a cemented lens group.

[0005] Preferably, the focal length of the optical system is set to 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 ratio with f: -2.0 <f1 / f<-1.0,51.0<f2 / f<52.0,1.0<f3 / f<2.0,0.0<f4 / f<1.0,-2.0<f5 / f<-1.0,13.0<f6 / f<14.0。

[0006] Preferably, the first lens satisfies the relationship: 1.6≤N d ≤1.9, V d ≤50.0; the second lens satisfies the relationship: 1.6≤N d ≤1.9, 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: 1.5≤N d ≤1.8, V d ≥50.0; the fifth lens satisfies the relationship: 1.6≤N d ≤1.9, 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 constant.

[0007] Preferably, the axial distances between the lenses satisfy the following relationship: the air gap between the first lens and the second lens is 2.5 to 3.0 mm; the air gap between the second lens and the third lens is 0.1 to 0.5 mm; the air gap between the third lens and the aperture is 1.5 to 2.0 mm; the air gap between the aperture and the fourth lens is 0.5 to 1.0 mm; the fourth lens and the fifth lens are a cemented lens group, and the air gap is 0 mm; the air gap between the fifth lens and the sixth lens is 1.5 to 2.0 mm.

[0008] Preferably, the aspheric curve equations of the first and sixth lenses are 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] Preferably, the total optical length TTL of the optical system and the focal length f of the optical system satisfy the following relationship: TTL / f≤5.0.

[0012] Preferably, the F number of the optical system is ≤1.5.

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

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

[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 120 degrees. It has the advantages of high imaging clarity, large aperture, low tolerance sensitivity and good high and low temperature stability. At the same time, it can monitor the scene in front of the vehicle more comprehensively.

[0017] 2. Through the reasonable matching of optical lenses, the system structure is compact and reasonable, the overall volume is reduced, it is easy to assemble, the tolerance sensitivity is low, and it is more suitable for large-scale high-yield production;

[0018] 3. The all-glass lens structure can compensate for focal plane displacement at high and low temperatures, and has high adaptability to complex environments;

[0019] 4. The axial chromatic aberration, vertical chromatic aberration and high-order chromatic aberration are corrected to ensure that the imaging system can have high imaging quality even at a large angle.

[0020] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the optical structure of the utility model;

[0022] Figure 2 It is the axial chromatic aberration diagram of the full working band of the utility model;

[0023] Figure 3 It is the vertical axis chromatic aberration diagram of the full working band of the utility model;

[0024] Figure 4 It is the field curvature distortion diagram of the full working band of the utility model;

[0025] In the figure: STO-aperture; L1-first lens; L2-second lens; L3-third lens; L4-fourth lens; L5-fifth lens; L6-sixth lens; L7-equivalent glass plate 1; L8-equivalent glass plate 2; IMA-imaging surface. DETAILED DESCRIPTION

[0026] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0027] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] like Figures 1 to 4 As shown, this embodiment provides a forward-looking ultra-wide-angle binocular camera, and 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 in sequence from left to right along the incident light path of the light; without considering the backcurvature caused by the aspheric coefficient, the first lens is a meniscus concave negative lens, whose object side surface is convex, and whose image side surface is concave; the second lens is a meniscus concave positive lens, whose object side surface is concave, and whose image side surface is convex; the third lens is a meniscus convex positive lens, whose object side surface is convex, and whose image side surface is concave; the fourth lens is a double convex positive lens, whose object side surface is convex, and whose image side surface is convex; the fifth lens is a meniscus concave negative lens, whose object side surface is concave, and whose image side surface is convex; the sixth lens is a meniscus convex positive lens, whose object side surface is convex, and whose image side surface is concave; all lenses are made of glass material, wherein the first and sixth lenses are glass aspheric lenses, and the fourth and fifth lenses form a cemented lens group.

[0030] The first lens is a glass aspherical lens with negative focal length, which can adjust the wide angle light and reduce the distortion of the head. The fourth lens and the fifth lens form an achromatic doublet. Reasonable lens matching enables the head to achieve small size, ultra-wide angle, large aperture, day and night confocal, low temperature drift design, and at the same time, it has good correction for on-axis and off-axis aberrations, and has good imaging quality, such as Figures 2 to 4 shown.

[0031] In the embodiment of the utility model, the focal length of the optical system is set to 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 ratio with f: -2.0 <f1 / f<-1.0,51.0<f2 / f<52.0,1.0<f3 / f<2.0,0.0<f4 / f<1.0,-2.0<f5 / f<-1.0,13.0<f6 / f<14.0。

[0032] In the embodiment of the utility model, the first lens satisfies the relationship: 1.6≤N d ≤1.9, V d ≤50.0; the second lens satisfies the relationship: 1.6≤N d ≤1.9, 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: 1.5≤N d ≤1.8, V d ≥50.0; the fifth lens satisfies the relationship: 1.6≤N d ≤1.9, 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 constant.

[0033] In the embodiment of the utility model, the axial distances between the lenses satisfy the following relationship: the air interval between the first lens and the second lens is 2.5-3.0 mm; the air interval between the second lens and the third lens is 0.1-0.5 mm; the air interval between the third lens and the aperture is 1.5-2.0 mm; the air interval between the aperture and the fourth lens is 0.5-1.0 mm; the fourth lens and the fifth lens are a cemented lens group, and the air interval is 0 mm; the air interval between the fifth lens and the sixth lens is 1.5-2.0 mm.

[0034] In the embodiment of the utility model, the aspheric curve equations of the first and sixth lenses are expressed as follows:

[0035]

[0036] 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.

[0037] 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.

[0038] In the embodiment of the utility model, the F number of the optical system is ≤1.5.

[0039] 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.

[0040] In an embodiment of the present invention, a filter is disposed on the rear side of the sixth lens.

[0041] An imaging method for a forward-looking ultra-wide-angle binocular camera is performed according to the following steps: an optical system is imaged after passing through a first lens, a second lens, a third lens, an aperture, a fourth lens, a fifth lens, and a sixth lens in sequence.

[0042] In the embodiment of the utility model, the technical indicators achieved by the head of this embodiment are as follows:

[0043] (1) Focal length: 5.0 ≤ EFFL ≤ 6.0 mm;

[0044] (2) Aperture F ≤ 1.5;

[0045] (3) Field of view: 2w ≥ 120°;

[0046] (4) Working band: visible light band.

[0047] To achieve the above design parameters, the specific design adopted by the head of this embodiment is shown in the following table:

[0048]

[0049]

[0050] The aspheric coefficients of the aspheric lenses of the head of this embodiment are as follows:

[0051]

[0052] The lens of this embodiment reduces the total length of the lens and the radial size of each lens while meeting the ultra-wide-angle imaging performance requirements of the lens by reasonably allocating the optical focal length, surface shape, center thickness of each lens and the axial distance between each lens, thereby miniaturizing the lens group.

[0053] The above is only the preferred embodiment of the utility model, and does not limit the utility model in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the utility model without departing from the technical solution of the utility model still belongs to the protection scope of the technical solution of the utility model.

Claims

1. A forward-looking ultra-wide-angle binocular camera, characterized in that: 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, which are arranged in sequence from left to right along the incident optical path of the light; without considering the backcurvature caused by the aspheric coefficient, the first lens is a meniscus concave negative lens, whose object side surface is convex and whose image side surface is concave; the second lens is a meniscus concave positive lens, whose object side surface is concave and whose image side surface is convex; the third lens is a meniscus convex positive lens, whose object side surface is convex and whose image side surface is concave; the fourth lens is a double convex positive lens, whose object side surface is convex and whose image side surface is convex; the fifth lens is a meniscus concave negative lens, whose object side surface is concave and whose image side surface is convex; the sixth lens is a meniscus convex positive lens, whose object side surface is convex and whose image side surface is concave; all lenses are made of glass material, among which the first and sixth lenses are glass aspheric lenses, and the fourth and fifth lenses form a cemented lens group.

2. The forward-looking ultra-wide-angle binocular camera according to claim 1, characterized in that: Assume 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, and the sixth lens are f1, f2, f3, f4, f5, and f6 respectively, where f1, f2, f3, f4, f5, and f6 satisfy the following ratio with f: -2.0 <f1 / f<-1.0,51.0<f2 / f<52.0,1.0<f3 / f<2.0,0.0<f4 / f<1.0,-2.0<f5 / f<-1.0,13.0<f6 / f<14.0。 3. The forward-looking ultra-wide-angle binocular camera according to claim 1, characterized in that: The first lens satisfies the relationship: 1.6≤N d ≤1.9, V d ≤50.0; the second lens satisfies the relationship: 1.6≤N d ≤1.9, 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: 1.5≤N d ≤1.8, V d ≥50.0; the fifth lens satisfies the relationship: 1.6≤N d ≤1.9, 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 constant.

4. The forward-looking ultra-wide-angle binocular camera according to claim 1, characterized in that: The axial distances between the lenses satisfy the following relationship: the air gap between the first lens and the second lens is 2.5 to 3.0 mm; the air gap between the second lens and the third lens is 0.1 to 0.5 mm; the air gap between the third lens and the aperture is 1.5 to 2.0 mm; the air gap between the aperture and the fourth lens is 0.5 to 1.0 mm; the fourth lens and the fifth lens are a cemented lens group with an air gap of 0 mm; the air gap between the fifth lens and the sixth lens is 1.5 to 2.0 mm.

5. The forward-looking ultra-wide-angle binocular camera according to claim 1, characterized in that: The aspheric curve equations of the first and sixth lenses are as follows: 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 forward-looking ultra-wide-angle binocular 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 forward-looking ultra-wide-angle binocular camera according to claim 1, characterized in that: The F number of the optical system is ≤1.

5.

8. The forward-looking ultra-wide-angle binocular 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 forward-looking ultra-wide-angle binocular camera according to claim 1, characterized in that: A filter is arranged at the rear side of the sixth lens.

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