4k thermal stable dvr optical imaging system

Abstract

The application discloses a 4K thermal stable DVR optical imaging system, which comprises a first lens, a second lens, a third lens, a diaphragm, a fourth lens, a fifth lens, a sixth lens, a seventh lens, a filter, a protective glass and an image plane arranged in the direction from the object side to the image side. Through the reasonable use of the lenses with specific shapes and the definition of the optical power of each lens, the application realizes a large target surface design, the maximum target surface is greater than or equal to 9.56 mm, can match a 1 / 1.8 chip IMX728, a large aperture design F1.8, and can realize the recording and identification of objects on both sides of the road in a dark environment; the FOV is increased to 171 degrees, a large-angle picture can be shot, and the field of view is improved.

Description

Technical Field

[0001] This invention relates to the field of optical imaging technology, specifically a 4K thermally stabilized DVR optical imaging system. Background Technology

[0002] With the rapid development of technology, cars have become an indispensable part of people's lives, and more and more cars are equipped with in-car dashcams. After installation, dashcams can record video images and sound of the entire driving process, providing evidence for traffic accidents. Because dashcams need to record the state of the front or rear of the car, whether there have been any scrapes or collisions, and also need to record the license plate numbers of the vehicles involved in the collisions, there are high requirements for the clarity of the dashcam.

[0003] Currently, dashcam lens designs generally suffer from two major problems: a small lens surface area and a small aperture. The small lens surface area directly limits its compatibility with large-lens, high-pixel image sensor chips, affecting image clarity and detail capture. On the other hand, a small aperture results in less light intake, especially in low-light conditions. Insufficient light leads to an overall darker image, affecting not only brightness but also contrast and color saturation, thus impacting the overall recording quality of the dashcam. Summary of the Invention

[0004] This invention proposes a 4K thermally stabilized DVR optical imaging system, which combines the features of a large target area, large aperture, ultra-high resolution pixels, no calorification, and purple fringing optimization.

[0005] A 4K thermally stabilized DVR optical imaging system comprises, along the optical axis from the object plane to the image plane, the following components in sequence: a first lens, a second lens, a third lens, a fourth lens, an aperture stop, a fifth lens, a sixth lens, a seventh lens, a filter, a protective glass, and an image plane;

[0006] The first lens is a meniscus lens with negative optical power; the second lens is a concave-convex lens with negative optical power; the third lens is a biconvex lens with positive optical power; the fourth lens is a concave-convex lens with positive optical power; the fifth lens is a biconvex lens with positive optical power; the sixth lens is a biconcave lens with negative optical power; and the seventh lens is a biconvex lens with positive optical power.

[0007] The ratio of the focal length of the first to seventh lenses to the focal length of the optical imaging system satisfies the following set relationship:

[0008] 1.4 < |f1 / f| < 1.8, 9.8 < |f2 / f| < 10.4, 2.2 < |f3 / f| < 2.6, 4.0 < |f4 / f| < 4.4, 6.9 < |f5 / f| < 7.3, 1.4 < |f6 / f| < 1.8, 1.8 < |f7 / f| < 2.2, where f1 represents the effective focal length of the first lens, f2 represents the effective focal length of the second lens, f3 represents the effective focal length of the third lens, f4 represents the effective focal length of the fourth lens, f5 represents the effective focal length of the fifth lens, f6 represents the effective focal length of the sixth lens, f7 represents the effective focal length of the seventh lens, and f represents the effective focal length of the optical imaging system.

[0009] A further proposed solution is that the focal lengths of the fifth lens (f5), the sixth lens (f6), and the seventh lens (f7) of the optical imaging system satisfy the following condition: 0.8 < |(f5+f6) / (f5-f7)| < 1.5.

[0010] A further embodiment is that the Abbe coefficients of the first lens, the second lens, the third lens, and the seventh lens are all greater than 40 and less than 50; the Abbe coefficient of the fourth lens is greater than 53 and less than 58; the Abbe coefficient of the fifth lens is greater than 80 and less than 85; and the Abbe coefficient of the sixth lens is greater than 20 and less than 25.

[0011] A further approach is to have the optical imaging system satisfy the following condition:

[0012] 0.30 < Nd6 - Nd5 < 0.50;

[0013] 50 < Vd5 - Vd6 < 65;

[0014] -4.5 < f5 / f6 < -3.5;

[0015] Where Nd5 represents the refractive index of the fifth lens, Nd6 represents the refractive index of the sixth lens, Vd5 represents the Abbe number of the fifth lens, Vd6 represents the Abbe number of the sixth lens, f5 represents the focal length of the fifth lens, and f6 represents the focal length of the sixth lens.

[0016] A further approach is to make the radius of curvature R1 of the object side of the first lens equal to the radius of curvature R2 of the image side of the first lens.

[0017] It satisfies: 0.5 < (R1 - R2) / (R1 + R2) < 1.0.

[0018] A further approach is to ensure that the entrance pupil diameter EPD of the optical system and the maximum holoimage height IH corresponding to the maximum field of view satisfy the following condition: 4.5 < IH / EPD < 5.5.

[0019] A further embodiment is that the maximum hologram height (IH) of the optical imaging system satisfies the following conditions: IH ≥ 9.56 mm; the maximum field of view (FOV) of the optical imaging system is ≥ 171°.

[0020] A further option is to set the aperture of the optical imaging system to F / NO = 1.8.

[0021] A further approach is that the maximum holographic height IH of the optical imaging system and the effective focal length f of the optical imaging system satisfy the following condition: 2.3mm≤IH / f≤2.8mm.

[0022] A further embodiment is as follows: the first lens has a convex surface facing the object side and a concave surface facing the image side; the second lens has a concave surface facing the object side and a convex surface facing the image side; the third lens has convex surfaces on both the object-side and image-side sides, and the absolute value of the radius of curvature of the object-side side of the third lens is greater than the absolute value of the radius of curvature of the image-side side; the fourth lens has a concave surface facing the object side and a convex surface facing the image side; the fifth lens has a convex surface with a platform facing the object side and a convex surface facing the image side; the sixth lens has concave surfaces on both the object-side and image-side sides, and the absolute value of the radius of curvature of the object-side side of the sixth lens is greater than the absolute value of the radius of curvature of the image-side side; the seventh lens has convex surfaces on both the object-side and image-side sides, and the absolute value of the radius of curvature of the object-side side of the seventh lens is less than the absolute value of the radius of curvature of the image-side side.

[0023] In summary, the present invention has the following beneficial effects: The present invention discloses a 4K thermally stabilized DVR optical imaging system, and particularly relates to a 4K thermally stabilized DVR optical imaging system that takes into account a large target area, a large aperture, ultra-high resolution pixels, no pyrolysis, and purple fringing optimization. The optical imaging system includes a first lens, a second lens, a third lens, an aperture stop, a fourth lens, a fifth lens, a sixth lens, a seventh lens, a filter, a protective glass, and an image plane arranged along the direction from the object side to the image side. This invention achieves a large target surface design with a maximum target surface of ≥9.56mm by rationally utilizing lenses of specific shapes and structures and limiting the optical power of each lens. It can be matched with the 1 / 1.8 chip IMX728 and features a large aperture design of F1.8, enabling the recording and recognition of objects on both sides of the road in low-light environments. The FOV is increased to 171 degrees, allowing for the capture of wide-angle images and improving the field of view. The combination of 5G+2GM spherical and aspherical lenses optimizes the high and low temperature drift compensation of the entire optical imaging system, allowing the operating temperature to range from -40 degrees to 95 degrees, greatly improving the application of this product in complex temperature scenarios. The use of low dispersion materials and a two-piece glass aspherical design optimizes the lens's purple fringing, reducing it to less than 3µm, thus improving the image quality degradation problem caused by severe purple fringing in most lenses. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a 4K thermally stabilized DVR optical imaging system according to an embodiment of the present invention;

[0025] Figure 2 MTF analysis diagram of the optical imaging system provided in this embodiment of the invention at 20°C in visible light;

[0026] Figure 3 Defocus curve of the optical imaging system provided in this embodiment of the invention at 20°C in visible light;

[0027] Figure 4 The defocus curve of the optical imaging system provided in this embodiment of the invention at -40°C in visible light;

[0028] Figure 5 A defocus curve of the optical imaging system provided in this embodiment of the invention at 95°C in visible light;

[0029] Figure 6 Field curvature diagram of the optical imaging system provided in the embodiments of the present invention in visible light;

[0030] Figure 7 The F-THETA distortion diagram of the optical imaging system provided in the embodiments of the present invention in visible light;

[0031] Figure 8 A relative illumination diagram of the optical imaging system provided in an embodiment of the present invention in visible light;

[0032] Figure 9 The transverse chromatic aberration diagram of the optical imaging system provided in the embodiments of the present invention at wavelengths of 435nm-656nm;

[0033] Figure 10 A standard dot plot of the optical imaging system provided in an embodiment of the present invention in visible light. Detailed Implementation

[0034] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0035] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0036] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0037] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0038] like Figure 1 As shown, the present invention provides a 4K thermally stabilized DVR optical imaging system, which includes a first lens E1, a second lens E2, and a third lens arranged along the direction from the object side to the image side.

[0039] E3, aperture stop STO, fourth lens E4, fifth lens E5, sixth lens E6, seventh lens E7, infrared filter IR, protective glass CG, and image plane IMA. The first lens E1 is a negative meniscus lens; the second lens E2 is a negative concave-convex lens; the third lens E3 is a positive biconvex lens; the fourth lens E4 is a positive concave-convex lens; the fifth lens E5 is a positive biconvex lens; the sixth lens E6 is a negative biconcave lens; the seventh lens E7 is a positive biconvex lens.

[0040] It should be noted that the present invention adopts a 5G + 2GM design, that is, five glass spherical lenses and two glass aspherical lenses. The aspherical lenses can better control the refraction and focusing of light, reduce aberration and chromatic aberration, improve imaging quality and resolution. At the same time, the combination of spherical and aspherical lenses optimizes the compensation for temperature drift at high and low temperatures, ensuring that the image remains clear when the lens works at high and low temperatures, and has a cost advantage and higher cost performance.

[0041] Among them, the ratio of the focal lengths of the first lens E1 to the seventh lens E7 to the focal length of the optical imaging system satisfies the following set relationship:

[0042] 1.4 < |f1 / f| < 1.8, 9.8 < |f2 / f| < 10.4, 2.2 < |f3 / f| < 2.6, 4.0 < |f4 / f| < 4.4, 6.9 < |f5 / f| < 7.3, 1.4 < |f6 / f| < 1.8, 1.8 < |f7 / f| < 2.2, where f1 represents the effective focal length of the first lens E1, f2 represents the effective focal length of the second lens E2, f3 represents the effective focal length of the third lens E3, f4 represents the effective focal length of the fourth lens E4, f5 represents the effective focal length of the fifth lens E5, f6 represents the effective focal length of the sixth lens E6, f7 represents the effective focal length of the seventh lens E7, and f represents the effective focal length of the optical imaging system.

[0043] In this embodiment, the third lens E3 of the optical imaging system adopts an aspherical design. The effective focal length f of the optical imaging system, the focal length f1 of the first lens E1, and the focal length f3 of the third lens E3 satisfy: -1.8 < f1 / f < -1.4, 2.2 < f3 / f < 2.6. Meeting the above range can make the first lens E1 have an appropriate negative optical power, and the third lens E3 have a certain positive optical power, so that the light is first diverged by the negative optical power of the first lens E1 and then converged by the subsequent positive optical power of the third lens E3, increasing the field angle; at the same time, the aspherical lens can correct problems such as spherical lens aberration. Using an aspherical lens can better control the propagation path of light, reduce aberration, and improve imaging quality, thereby achieving a larger field angle.

[0044] Furthermore, the focal lengths f5 of the fifth lens E5, f6 of the sixth lens E6, and f7 of the seventh lens E7 in the optical imaging system satisfy: 0.8 < |(f5+f6) / (f5-f7)| < 1.5. Satisfying the above range can widen the beam width when large-angle light passes through the sixth lens E6 and the seventh lens E7. This process enables the light to be transmitted to the imaging surface fully and efficiently, thereby expanding the maximum target surface of the optical imaging system.

[0045] The Abbe coefficients of the first lens E1, the second lens E2, the third lens E3, and the seventh lens E7 are all greater than 40 and less than 50; the Abbe coefficient of the fourth lens E4 is all greater than 53 and less than 58; the Abbe coefficient of the fifth lens E5 is all greater than 80 and less than 85; and the Abbe coefficient of the sixth lens E6 is all greater than 20 and less than 25.

[0046] As an improvement, the optical imaging system satisfies the following condition:

[0047] 0.30 < Nd6 - Nd5 < 0.50;

[0048] 50 < Vd5 - Vd6 < 65;

[0049] -4.5 < f5 / f6 < -3.5;

[0050] Where Nd5 represents the refractive index of the fifth lens E5, Nd6 represents the refractive index of the sixth lens E6, Vd5 represents the Abbe number of the fifth lens E5, Vd6 represents the Abbe number of the sixth lens E6, f5 represents the focal length of the fifth lens E5, and f6 represents the focal length of the sixth lens E6. By satisfying the above conditions and rationally allocating and balancing the optical power and dispersion relationship between the fifth lens E5 and the sixth lens E6, and by using a low-dispersion material for the fifth lens E5, chromatic aberration of the system can be effectively corrected, improving image quality. Furthermore, it can effectively reduce the refraction angle of light within the lens, reducing the sensitivity of lens production and improving product yield.

[0051] As an improvement, the object-side radius of curvature R1 of the first lens E1 and the image-side radius of curvature R2 of the first lens E2 satisfy the condition: 0.5 < (R1-R2) / (R1+R2) < 1.0. Meeting this range limits the object-side and image-side radius of curvature of the first lens E1, making the refraction and propagation of light within the lens more reasonable, thus achieving an ultra-wide-angle effect.

[0052] As an improvement, the entrance pupil diameter EPD of this optical system and the maximum holographic height IH corresponding to the maximum field of view satisfy: 4.5 < IH / EPD < 5.5. Satisfying the above range allows for a wider beam width entering the optical system, which is beneficial for the design of a large aperture in the optical system and enables clear imaging even in low-light environments.

[0053] Preferably, in the optical imaging system provided in the embodiments of the present invention, the maximum hologram height IH of the optical imaging system satisfies the following condition: IH≥9.56mm.

[0054] Preferably, in the optical imaging system provided in the embodiments of the present invention, the maximum field of view of the optical imaging system is FOV ≥ 171°.

[0055] Preferably, in the optical imaging system provided in the embodiments of the present invention, the aperture of the optical imaging system is F / NO = 1.8.

[0056] Preferably, in the optical imaging system provided in the embodiments of the present invention, the maximum holographic height IH and the effective focal length f of the optical imaging system satisfy the following condition: 2.3mm ≤ IH / f ≤ 2.8mm. Satisfying this range ensures a large target area for the optical system while optimizing the depth of field and guaranteeing the imaging quality of the optical imaging system.

[0057] Preferably, the first lens E1 has a convex surface S1 facing the object side and a concave surface S2 facing the image side; the second lens E2 has a concave surface S3 facing the object side and a convex surface S4 facing the image side; the third lens E3 has a slightly convex surface S5 facing the object side and a large convex surface S6 facing the image side; the fourth lens E4 has a concave surface S8 facing the object side and a convex surface S9 facing the image side; the fifth lens E5 has a convex surface S10 facing the object side with a platform and a convex surface S11 facing the image side; the sixth lens E6 has a slightly concave surface S11 facing the object side and a large concave surface S12 facing the image side; and the seventh lens E7 has a large convex surface S13 facing the object side and a slightly convex surface S14 facing the image side.

[0058] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0059] The parameters of each lens in this embodiment are listed in Table 1 below, and the aspherical coefficients of the lenses are shown in Table 2 below.

[0060] Table 1 Physical parameters of each lens

[0061]

[0062] Table 2 Aspherical coefficients of lenses

[0063]

[0064] The aspherical coefficients satisfy the following equation:

[0065]

[0066] Where z is the aspherical sagitta, c is the paraxial curvature of the aspherical surface, the curvature is the reciprocal of the radius of curvature, y is the lens aperture, k is the conic coefficient, a4 is the 4th order aspherical coefficient, a6 is the 6th order aspherical coefficient, a8 is the 8th order aspherical coefficient, a10 is the 10th order aspherical coefficient, and a12 is the 12th order aspherical coefficient.

[0067] Specifically, the R-values ​​and thicknesses of each lens surface in this embodiment are shown in Table 1, and the aspherical parameters are shown in Table 2.

[0068] Specifically, in this embodiment, the R-value (radius of curvature), thickness, refractive index, Abbe number (ABB), and focal length (EFL-E) of each lens surface are shown in Table 1, and the aspherical parameters are shown in Table 2. In Table 1, Surf represents the mirror number, and InFInITY represents infinity. In Table 2, R1 represents the radius of curvature of the corresponding lens surface facing the object side, and R2 represents the radius of curvature of the corresponding lens surface facing the image side. A positive radius of curvature indicates that the mirror is curved towards the object side, and a negative radius of curvature indicates that the mirror is curved towards the image side.

[0069] The optical imaging system provided in Table 1 has an effective focal length of 3.63 mm, a total image height of 9.56 mm, a maximum field of view of 171 degrees, and an aperture of F / N1.8. In Table 1, mirror numbers 1 and 2 represent the two mirrors of lens 1 along the direction of light incidence, mirror numbers 3 and 4 represent the two mirrors of lens 2 along the direction of light incidence, mirror numbers 5 and 6 represent the two mirrors of lens 3 along the direction of light incidence, mirror numbers 8 and 9 represent the two mirrors of lens 4 along the direction of light incidence, mirror number 10 represents the object-side mirror of lens 5, mirror number 11 represents the cemented surface of lenses 5 and 6, mirror number 12 represents the image-side mirror of lens 6, and mirror numbers 13 and 14 represent the two mirrors of lens 7 along the direction of light incidence.

[0070] In an embodiment of the present invention, Figure 2This is a modulation transfer function (MTF) curve for the visible light band, representing the overall resolving power of an optical imaging system. The horizontal axis represents spatial frequency, in cycles per millimeter (mm), and the vertical axis represents the MTF value. The MTF value is used to evaluate the image quality of a lens, ranging from 0 to 1. It is worth noting that the optical transfer function is a relatively accurate, intuitive, and common way to evaluate the image quality of an optical imaging system. The higher and smoother the curve, the better the image quality and the stronger the ability to reproduce the true image. Figure 2 It can be seen that in the visible light band, the MTF in the imaging region near the center is >0.7, indicating good imaging quality. Figure 3 The defocus curve shows that the lens has good MTF concentration, making focusing easy. From... Figure 4 and Figure 5 It can be seen that the defocus curves at both high and low temperatures meet the requirements of high resolution, with small changes in focus, and no blurring in both high and low temperature environments; Figure 6 Represented as a field curve diagram, by Figure 6 It can be seen that the field curvature value should be controlled between -0.12mm and 0.12mm. The smaller the field curvature value, the better the image quality of the lens. Figure 7 This is represented as an F-THETA distortion map. The smaller the F-THETA distortion, the less the compression at the edges of the image. Figure 8 This is represented as a relative illumination diagram; the higher the relative illumination, the higher the overall brightness of the captured image. Figure 9 Represented as a vertical axis chromatic aberration diagram, the smaller the vertical axis chromatic aberration, the better the color reproduction of the image and the better the purple fringing optimization; Figure 10 It is represented as a standard point array diagram.

Claims

1. A 4K thermally stabilized DVR optical imaging system, characterized in that: Along the optical axis from the object plane to the image plane, the following components are included in sequence: first lens, second lens, third lens, fourth lens, aperture stop, fifth lens, sixth lens, seventh lens, filter, protective glass, and image plane; The first lens is a meniscus lens with negative optical power; the second lens is a concave-convex lens with negative optical power; the third lens is a biconvex lens with positive optical power; the fourth lens is a concave-convex lens with positive optical power; the fifth lens is a biconvex lens with positive optical power; the sixth lens is a biconcave lens with negative optical power; and the seventh lens is a biconvex lens with positive optical power. The third and seventh lenses are non-glass aspherical lenses. The ratio of the focal length of the first to seventh lenses to the focal length of the optical imaging system satisfies the following set relationship: 1.4 < |f1 / f| < 1.8, 9.8 < |f2 / f| < 10.4, 2.2 < |f3 / f| < 2.6, 4.0 < |f4 / f| < 4.4, 6.9 < |f5 / f| < 7.3, 1.4 < |f6 / f| < 1.8, 1.8 < |f7 / f| < 2.2, where f1 represents the effective focal length of the first lens, f2 represents the effective focal length of the second lens, f3 represents the effective focal length of the third lens, f4 represents the effective focal length of the fourth lens, f5 represents the effective focal length of the fifth lens, f6 represents the effective focal length of the sixth lens, f7 represents the effective focal length of the seventh lens, and f represents the effective focal length of the optical imaging system; The maximum holoimage height (IH) of the optical imaging system meets the following conditions: IH ≥ 9.56 mm; the maximum field of view (FOV) of the optical imaging system is ≥ 171°.

2. The 4K thermally stabilized DVR optical imaging system according to claim 1, characterized in that: The focal lengths f5 of the fifth lens, f6 of the sixth lens, and f7 of the seventh lens in the optical imaging system satisfy: 0.8 < |(f5+f6) / (f5-f7)| < 1.

5.

3. The 4K thermally stabilized DVR optical imaging system according to claim 1, characterized in that: The Abbe coefficients of the first, second, third, and seventh lenses are all greater than 40 and less than 50; the Abbe coefficient of the fourth lens is greater than 53 and less than 58; the Abbe coefficient of the fifth lens is greater than 80 and less than 85; and the Abbe coefficient of the sixth lens is greater than 20 and less than 25.

4. The 4K thermally stabilized DVR optical imaging system according to claim 3, characterized in that: Optical imaging systems satisfy the following condition: 0.30 < Nd6 - Nd5 < 0.50; 50 < Vd5 - Vd6 < 65; -4.5 < f5 / f6 < -3.5; Where Nd5 represents the refractive index of the fifth lens, Nd6 represents the refractive index of the sixth lens, Vd5 represents the Abbe number of the fifth lens, Vd6 represents the Abbe number of the sixth lens, f5 represents the focal length of the fifth lens, and f6 represents the focal length of the sixth lens.

5. The 4K thermally stabilized DVR optical imaging system according to claim 1, characterized in that: The radius of curvature R1 of the object side surface of the first lens and the radius of curvature R2 of the image side surface of the first lens It satisfies: 0.5 < (R1 - R2) / (R1 + R2) < 1.

0.

6. The 4K thermally stabilized DVR optical imaging system according to claim 1, characterized in that: The entrance pupil diameter EPD of the optical system and the maximum holoimage height IH corresponding to the maximum field of view satisfy: 4.5 < IH / EPD < 5.

5.

7. A 4K thermally stabilized DVR optical imaging system according to claim 1 or 3, characterized in that: The aperture of the optical imaging system is F / NO = 1.

8.

8. A 4K thermally stabilized DVR optical imaging system according to claim 1 or 3, characterized in that: The maximum hologram height (IH) of the optical imaging system and the effective focal length (f) of the optical imaging system satisfy the following condition: 2.3mm ≤ IH / f ≤ 2.8mm.

9. The 4K thermally stabilized DVR optical imaging system according to claim 1, characterized in that: The first lens has a convex surface facing the object side and a concave surface facing the image side; the second lens has a concave surface facing the object side and a convex surface facing the image side; the third lens has convex surfaces on both the object-side and image-side sides, and the absolute value of the radius of curvature of the object-side side of the third lens is greater than the absolute value of the radius of curvature of the image-side side; the fourth lens has a concave surface facing the object side and a convex surface facing the image side; the fifth lens has a convex surface with a platform facing the object side and a convex surface facing the image side; the sixth lens has concave surfaces on both the object-side and image-side sides, and the absolute value of the radius of curvature of the object-side side of the sixth lens is greater than the absolute value of the radius of curvature of the image-side side; the seventh lens has convex surfaces on both the object-side and image-side sides, and the absolute value of the radius of curvature of the object-side side of the seventh lens is less than the absolute value of the radius of curvature of the image-side side.

Images