Large-target-surface super-definition ADAS optical system

Abstract

The utility model discloses a large-target-surface super-definition ADAS optical system, which sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens, a seventh lens, an eighth lens, an optical filter, protective glass and an image surface from an object surface to an image surface along an optical axis, the object plane side of the first lens is a convex surface, and the image plane side is a concave surface. The object surface side of the second lens is a convex surface, and the image surface side is a concave surface; the object plane side of the third lens is a concave surface, and the image plane side is a concave surface; the object plane side of the fourth lens is a convex surface, and the image plane side is a convex surface; the object plane side of the fifth lens is a convex surface, and the image plane side is a convex surface; the object plane side of the sixth lens is a concave surface, and the image plane side is a concave surface; the object plane side of the seventh lens is a convex surface, and the image plane side is a convex surface; the object plane side of the eighth lens is a concave surface, and the image plane side is a convex surface. The large-target-surface super-definition ADAS optical system has the advantages of being large in target surface, super-definition in pixel, long in focus, optimized in purple edge and stable in thermal drift.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of optical imaging technology, concretely is a kind of big target surface super-clear ADAS optical system. BACKGROUND

[0002] ADAS is through the various sensors (such as radar, laser radar LiDAR, camera, ultrasonic sensor and GPS etc.) integrated on vehicle to collect the environmental data around vehicle, then utilize computer vision, deep learning etc. Advanced technology is handled and analyzed to these data, to realize the identification, tracking and prediction of static and dynamic objects around vehicle. This system can perceive potential danger (such as pedestrian crossing, front vehicle sudden stop, lane deviation etc.) in advance, and warn driver by sound, image or haptics etc., even in some cases automatically take evasive measures, greatly improve the safety and comfort of driving.

[0003] With the development of science and technology, the image sensor chip in imaging system is constantly updated and iterated, and the imaging requirements of the lens are also higher and higher. Most of the vehicle-mounted ASDS lenses have small target surfaces, poor resolution and short focal length, and the imaging quality is not good in high or low temperature environment, the purple edge of the photographed object edge is serious, which affects the recognition and tracking of the object. Therefore, how to provide a lens with large target surface, super-clear, long focal length, good imaging effect in high or low temperature environment and optimized purple edge is a problem to be solved by those skilled in the art. CONTENT OF THE UTILITY MODEL

[0004] The utility model provides a kind of big target surface super-clear ADAS optical system, this kind of big target surface super-clear ADAS optical system has the characteristics of large target surface, super-clear pixel, long focus, purple edge optimization, thermal drift stability under high-low temperature environment.

[0005] The above technical purpose of the utility model is realized by the following technical scheme: a kind of big target surface super-clear ADAS optical system, sequentially includes: first lens, second lens, third lens, fourth lens, diaphragm, fifth lens, sixth lens, seventh lens, eighth lens, optical filter, protective glass and image surface along optical axis from object surface to image surface;

[0006] The first lens object surface side is convex, and the image surface side is concave;

[0007] The second lens object surface side is convex, and the image surface side is concave;

[0008] The third lens object surface side is concave, and the image surface side is concave;

[0009] The fourth lens object surface side is convex, and the image surface side is convex;

[0010] The fifth lens object surface side is convex, and the image surface side is convex;

[0011] the sixth lens has a concave object side and a concave image side;

[0012] the seventh lens has a convex object side and a convex image side;

[0013] the eighth lens has a concave object side and a convex image side;

[0014] the fifth lens and the sixth lens form a cemented lens;

[0015] and satisfy the following relationship:

[0016] 1.2 < |f1 / f| < 1.7; 0.6 < |f2 / f| < 1.2; 0.5 < |f3 / f| < 1.1; 0.8 < |f4 / f| < 1.3; 1.7 < |f5 / f| < 2.2; 0.8 < |f6 / f| < 1.5; 0.5 < |f7 / f| < 1.1; 0.7 < |f8 / f| < 1.3;

[0017] wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, f7 is the focal length of the seventh lens, f8 is the focal length of the eighth lens, and f is the effective focal length of the entire optical system.

[0018] Further, the Abbe number Vd1 of the first lens, the Abbe number Vd2 of the second lens, the Abbe number Vd3 of the third lens, the Abbe number Vd6 of the sixth lens, and the Abbe number Vd7 of the seventh lens are all greater than 29 and less than 37.

[0019] Further, the maximum total image height of the optical system satisfies the following condition:

[0020] IH max ≥ 9.69 mm.

[0021] Further, the effective focal length f of the optical system satisfies the following condition:

[0022] 14.85 mm ≤ f ≤ 14.95 mm.

[0023] Further, the first lens is of a concave-convex type, has a convex object side and a concave image side with a platform, and has a negative refractive power;

[0024] the second lens is of a concave-convex type, has a convex object side and a concave image side, and has a positive refractive power;

[0025] the third lens is of a double-concave type, has a concave object side and a concave image side, and has a negative refractive power;

[0026] The fourth lens is biconvex, the object plane side is a small convex surface, the image plane side is a large convex surface, and the optical power is positive;

[0027] The fifth lens is biconvex, the object plane side is a convex surface, the image plane side is a convex surface, and the optical power is positive;

[0028] The sixth lens is biconcave, the object plane side is a concave surface with a platform, the image plane side is a concave surface, and the optical power is negative;

[0029] The seventh lens is biconvex, the object plane side is a small convex surface, the image plane side is a large convex surface, and the optical power is positive;

[0030] The eighth lens is meniscus, the object plane side is a concave surface with a platform, the image plane side is a convex surface, and the optical power is negative.

[0031] Further, 3 < L / IH max <4.

[0032] Wherein L represents the total length of the optical system, IH max represents the maximum total image height of the optical system.

[0033] Further, when the working distance is infinite, the total focal length f of the optical system is 14.92mm, the FNO is 2.4, and the maximum image circle is 9.69mm.

[0034] In summary, the utility model has the following beneficial effects:

[0035] (1), super large target surface: the maximum target surface (the maximum total image height) of the optical system is greater than or equal to 9.69mm, the larger the target surface, the larger the chip size that can be matched, and the demand for matching high-definition large target chip in the market is met.

[0036] (2), super long focal length 14.85mm ≤ f ≤ 14.95mm: meet the requirements of long-distance detection, and the static and dynamic objects around the vehicle at a distance can be better identified, tracked and predicted, and the safety of driving is ensured.

[0037] (3), super clear shooting: meet 8 million pixel high-quality shooting, and can present high-resolution, high-brightness picture effect.

[0038] (4), thermal drift stability under high and low temperature environment: the whole optical system has a thermal compensation effect, and when the working temperature is-40 DEG C to 85 DEG C, the resolving power of the product can be well ensured to be basically unchanged. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 The optical system schematic diagram provided by the utility model embodiment is shown in the figure;

[0040] Figure 2The MTF analysis diagram provided by the embodiment of the utility model;

[0041] Figure 3 The defocus curve graph of the optical system at 20 DEG C provided by the embodiment of the utility model;

[0042] Figure 4 The defocus curve graph of the optical system at -40 DEG C provided by the embodiment of the utility model;

[0043] Figure 5 The defocus curve graph of the optical system at 85 DEG C provided by the embodiment of the utility model;

[0044] Figure 6 The field curve graph of the optical system provided by the embodiment of the utility model;

[0045] Figure 7 The distortion curve graph of the optical system provided by the embodiment of the utility model.

[0046] Figure 8 The relative luminance graph of the optical system provided by the embodiment of the utility model. DETAILED DESCRIPTION

[0047] The embodiments of the utility model are described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the utility model, and cannot be understood as a limitation of the utility model.

[0048] In the description of the utility model, it is understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the utility model.

[0049] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the utility model, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0050] In the utility model, unless another explicit provision and limitation, the terms "mount", "connect", "connect", "fix" and so on terms should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated;Can be mechanical connection, also can be electrical connection;Can be directly connected, also can be indirectly connected through intermediate medium, can be two element internal communication or two element mutual action relation.For ordinary skilled person in the art, the above terms can be understood according to the specific meaning in the utility model.

[0051] As Figure 1 The embodiment provides a large target surface super-clear ADAS optical system, which sequentially comprises a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a diaphragm STO, a fifth lens E5, a sixth lens E6, a seventh lens E7, an eighth lens E8, a filter IR, a protective glass CG and an image plane IMA along an optical axis from an object plane to an image plane.

[0052] The object plane side S1 of the first lens E1 is a convex surface, and the image plane side S2 is a concave surface.

[0053] The object plane side S3 of the second lens E2 is a convex surface, and the image plane side S4 is a concave surface.

[0054] The object plane side S5 of the third lens E3 is a concave surface, and the image plane side S6 is a concave surface.

[0055] The object plane side S7 of the fourth lens E4 is a convex surface, and the image plane side S8 is a convex surface.

[0056] The object plane side S10 of the fifth lens E5 is a convex surface, and the image plane side S11 is a convex surface.

[0057] The object plane side S11 of the sixth lens E6 is a concave surface, and the image plane side S12 is a concave surface.

[0058] The object plane side S13 of the seventh lens E7 is a convex surface, and the image plane side S14 is a convex surface.

[0059] The object plane side S15 of the eighth lens E8 is a concave surface, and the image plane side S16 is a convex surface.

[0060] The fifth lens E5 and the sixth lens E6 form a set of cemented lenses.

[0061] And the following relationship is satisfied:

[0062] 1.2<|f1 / f|<1.7;0.6<|f2 / f|<1.2;0.5<|f3 / f|<1.1;0.8<|f4 / f|<1.3;1.7<|f5 / f|<2.2;0.8<|f6 / f|<1.5;0.5<|f7 / f|<1.1;0.7<|f8 / f|<1.3;

[0063] wherein f1 is the focal length of the first lens E1, f2 is the focal length of the second lens E2, f3 is the focal length of the third lens E3, f4 is the focal length of the fourth lens E4, f5 is the focal length of the fifth lens E5, f6 is the focal length of the sixth lens E6, f7 is the focal length of the seventh lens E7, f8 is the focal length of the eighth lens E8, and f is the effective focal length of the entire optical system.

[0064] As an improvement, the Abbe number Vd1 of the first lens E1, the Abbe number Vd2 of the second lens E2, the Abbe number Vd3 of the third lens E3, the Abbe number Vd6 of the sixth lens E6, and the Abbe number Vd7 of the seventh lens E7 are all greater than 29 and less than 37.

[0065] As an improvement, the maximum total image height of the optical system satisfies the following condition:

[0066] IHmax≥ 9.69 mm.

[0067] As an improvement, the effective focal length f of the optical system satisfies the following condition:

[0068] 14.85 mm ≤ f ≤ 14.95 mm.

[0069] As an improvement, the first lens E1 is of meniscus type, and the object side S1 is a convex surface, and the image side S2 is a concave surface with a platform, and the power is negative;

[0070] The second lens E2 is of meniscus type, and the object side S3 is a convex surface, and the image side S4 is a concave surface, and the power is positive;

[0071] The third lens E3 is of double concave type, and the object side S5 is a concave surface, and the image side S6 is a concave surface, and the power is negative;

[0072] The fourth lens E4 is of double convex type, and the object side S7 is a small convex surface, and the image side S8 is a large convex surface, and the power is positive;

[0073] The fifth lens E5 is of double convex type, and the object side S9 is a convex surface, and the image side S10 is a convex surface, and the power is positive;

[0074] The sixth lens E6 is of double concave type, and the object side S11 is a concave surface with a platform, and the image side S12 is a concave surface, and the power is negative;

[0075] The seventh lens E7 is of double convex type, and the object side S13 is a small convex surface, and the image side S14 is a large convex surface, and the power is positive;

[0076] The eighth lens E8 is of meniscus type, and the object side S15 is a concave surface with a platform, and the image side S16 is a convex surface, and the power is negative.

[0077] As an improvement, the optical system satisfies the following conditions:

[0078] 3 < L / IH max <4

[0079] where L represents the total length of the optical system, IH max represents the maximum total image height of the optical system.

[0080] In the patent embodiment, when the working distance is infinite, the total focal length of the optical system is f=14.92mm, the FNO is 2.4, and the maximum total image height is 9.69mm.

[0081] The specific embodiment is only an explanation of the utility model, and is not a limitation of the utility model. Those skilled in the art can make modifications to the embodiment without creative contribution after reading the specification, but as long as the modifications are within the scope of the claims of the utility model, they are protected by the patent law.

[0082] In the embodiment, the parameters of each lens are listed in Table 1 in turn.

[0083] Table 1 Physical parameters of each lens

[0084]

[0085] Specifically, in the embodiment, the surface number (surface), R value (radius of curvature), thickness (thickness), refractive index (index), Abbe number (ABB), and lens focal length (EFL-E) of each lens surface are shown in Table 1. INFINITY in Table 1 represents infinity.

[0086] It should be noted that in Table 1, the positive curvature radius indicates that the mirror surface is curved towards the object surface, and the negative curvature radius indicates that the mirror surface is curved towards the image surface. The mirror surface numbers 1 and 2 represent the two mirror surfaces of the first lens E1 in the direction of light incidence, the mirror surface numbers 3 and 4 represent the two mirror surfaces of the second lens E2 in the direction of light incidence, the mirror surface numbers 5 and 6 represent the two mirror surfaces of the third lens E3 in the direction of light incidence, the mirror surface numbers 7 and 8 represent the two mirror surfaces of the fourth lens E4 in the direction of light incidence, the mirror surface number 10 represents the mirror surface of the fifth lens E5 towards the object, the mirror surface number 11 represents the cemented surface of the fifth lens E5 and the sixth lens E6, the mirror surface number 12 represents the mirror surface of the sixth lens E6 towards the image, the mirror surface numbers 13 and 14 represent the two mirror surfaces of the seventh lens E7 in the direction of light incidence, and the mirror surface numbers 15 and 16 represent the two mirror surfaces of the eighth lens E8 in the direction of light incidence.

[0087] In the embodiment of the utility model, Figure 2The modulation transfer function (MTF) curve in the visible light band represents the comprehensive resolving power of the optical system. The horizontal axis represents spatial frequency, with units of cycles per millimeter (cycles / mm), and the vertical axis represents the value of the modulation transfer function (MTF). The value of the MTF is used to evaluate the imaging quality of the optical system, and the value range is 0-1. It is particularly pointed out that the optical transfer function is a more accurate, intuitive and common way to evaluate the imaging quality of an optical system. The higher and smoother the curve, the better the imaging quality of the system and the stronger the restoration ability of the real image. From Figure 2 It can be seen that the MTF of the imaging area near the center is greater than 0.7 at a spatial frequency of 100 lp / mm in the visible light band, and the imaging quality is good. Figure 3 The defocus curve at 20°C in the visible light band is shown in the figure. Figure 3 It can be seen that the MTF concentration of the optical system is good, the focusing is convenient, and the defocus curve trends are consistent under different field angles. From Figure 4 and Figure 5 It can be seen that the defocus curves at low temperature-40°C and high temperature 85°C both meet the high resolution, the focal point change of the defocus curve is small, and the thermal drift effect is stable. Figure 6 The field curvature graph is shown in the figure. Figure 6 It can be seen that the field curvature value is controlled between-0.03 mm and 0.03 mm, and the smaller the field curvature value, the better the imaging quality of the optical system. Figure 7 The distortion graph is shown in the figure. The smaller the optical distortion, the smaller the edge deformation of the imaging picture. Figure 8 The relative luminance graph is shown in the figure. Figure 8 It can be seen that the relative luminance of the maximum edge field of view is greater than 85%, and the edge luminance is high. Under the condition of overcast, night and low brightness, it can still be clearly imaged, which fully meets the market technical requirements.

Claims

1. A large target surface super-clear ADAS optical system, characterized in that: sequentially comprising, along the optical axis from the object plane to the image plane: a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a filter, a protective glass and an image plane; the object plane side of the first lens is convex, and the image plane side is concave; the object plane side of the second lens is convex, and the image plane side is concave; the object plane side of the third lens is concave, and the image plane side is concave; the object plane side of the fourth lens is convex, and the image plane side is convex; the object plane side of the fifth lens is convex, and the image plane side is convex; the object plane side of the sixth lens is concave, and the image plane side is concave; the object plane side of the seventh lens is convex, and the image plane side is convex; the object plane side of the eighth lens is concave, and the image plane side is convex; the fifth lens and the sixth lens constitute a cemented lens; and the following relationships are satisfied: 1.2<|f1 / f|<1.7; 0.6<|f2 / f|<1.2; 0.5<|f3 / f|<1.1; 0.8<|f4 / f|<1.3; 1.7<|f5 / f|<2.2; 0.8<|f6 / f|<1.5; 0.5<|f7 / f|<1.1; 0.7<|f8 / f|<1.3; wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, f6 is the focal length of the sixth lens, f7 is the focal length of the seventh lens, f8 is the focal length of the eighth lens, and f is the effective focal length of the entire optical system. The Abbe number Vd1 of the first lens, the Abbe number Vd2 of the second lens, the Abbe number Vd3 of the third lens, the Abbe number Vd6 of the sixth lens and the Abbe number Vd7 of the seventh lens are all greater than 29 and less than 37. The maximum total image height of the optical system satisfies the following condition: 0.5<|h / f|<0.

6. The effective focal length f of the optical system satisfies the following condition: 14.85mm≤f≤14.95mm. 5.The large target surface super-clear ADAS optical system according to claim 1, characterized in that: the first lens is of meniscus type, and the object plane side is convex, and the image plane side is concave with a platform, and the optical power is negative; the second lens is of meniscus type, and the object plane side is convex, and the image plane side is concave, and the optical power is positive; the third lens is of double concave type, and the object plane side is concave, and the image plane side is concave, and the optical power is negative; the fourth lens is of double convex type, and the object plane side is small convex, and the image plane side is large convex, and the optical power is positive; the fifth lens is of double convex type, and the object plane side is convex, and the image plane side is convex, and the optical power is positive; the sixth lens is of double concave type, and the object plane side is concave with a platform, and the image plane side is concave, and the optical power is negative; the seventh lens is of double convex type, and the object plane side is small convex, and the image plane side is large convex, and the optical power is positive; and the eighth lens is of meniscus type, and the object plane side is concave with a platform, and the image plane side is convex, and the optical power is negative. 6.The large target surface super-clear ADAS optical system according to claim 1, characterized in that: ​ ​ ​ ​ ​ ​ ​ ​ 2. A large target area ultra-clear ADAS optical system according to claim 1, characterized in that: ​ 3. A large target area ultra-clear ADAS optical system according to claim 1, characterized in that: ​ IH max ≥ 9.69 mm.

4. A large target area ultra-clear ADAS optical system according to claim 1, characterized in that: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 3 < L / IH max <4, where L represents the total length of the optical system, IH max represents the maximum holographic height of the optical system.

7. A large target area ultra-sharp ADAS optical system according to claim 1, characterized in that: When the working distance is infinite, the total focal length of the optical system is f = 14.92 mm, FNO = 2.4, and the maximum holographic height is 9.69 mm.

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