Optical imaging device

Abstract

The invention relates to an optical imaging device, comprising: a lens barrel assembly, comprising a first lens barrel and a second lens barrel arranged in sequence, and a lens assembly, comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens arranged in sequence along an optical axis from an object side to an image side; the first lens, the second lens and the third lens are arranged in the first lens barrel, and the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are arranged in the second lens barrel; the optical imaging device satisfies the relationship: 0.1<T34 / f4<0.25; 0.60<d02s / R7<1.30; 0<d02s / R6≤0.40; the optical imaging device of the present application achieves a balance between a larger market angle and a smaller F number by optimizing the combination of lenses and the reasonable design of lens intervals; by optimizing the relationship between the inner diameter d02s of the lens barrel and the lens curvature radii R6 and R7 during the design process, the geometric matching between the lenses is controlled, the air gap change can be reduced, and the assembly error can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of optical elements, and in particular to an optical imaging device. Background Art

[0002] With the development of optical imaging technology, in the design of some wide-angle lenses, a larger field of view, a larger aperture and higher image quality have become an important topic in the current optical design field. In particular, as the F number (the inverse of the relative aperture) continues to decrease, the system's aberration control, beam transmission efficiency and mechanical stability are facing higher design requirements, and the wide-angle lenses of existing multi-lens systems for mobile phones usually find it difficult to maintain a balance between a larger field of view and a smaller F number.

[0003] Currently, some mobile phones use eight-piece lenses. Under the conditions of wide field of view and large aperture, the optical system has a small tolerance space, and assembly errors may aggravate the non-ideal performance of the optical system. Under this eight-piece lens design, due to the tightness of the lens combination design, as the optical axis defocuses, the MTF curve may show significant distortion or unfocusing. Summary of the invention

[0004] Based on this, it is necessary to provide an optical imaging device to address the problem that under the conditions of wide field angle and large aperture of the existing eight-piece lens, the assembly error has a greater impact on the optical system due to the small error tolerance of the optical system.

[0005] An optical imaging device, comprising:

[0006] A lens barrel assembly, the lens barrel assembly comprising a first lens barrel and a second lens barrel arranged in sequence, wherein the inner annular surface of the first lens barrel and the inner annular surface of the second lens barrel are both stepped;

[0007] A lens assembly, the lens assembly comprising a first lens with negative focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with positive focal power, a fifth lens with negative focal power, a sixth lens with positive focal power, a seventh lens with negative focal power and an eighth lens with positive focal power, which are sequentially arranged along an optical axis from an object side to an image side; the first lens, the second lens and the third lens are arranged in the first lens barrel, and the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are arranged in the second lens barrel; the object side surface of the first lens is a concave surface; the object side surface and the image side surface of the second lens are concave and convex surfaces respectively; the object side surface and the image side surface of the third lens are convex and concave surfaces respectively; the object side surface of the fourth lens is a convex surface; the object side surface and the image side surface of the fifth lens are convex and concave surfaces respectively; the image side surface of the sixth lens is a convex surface; the image side surface of the seventh lens is a concave surface; and the image side surface of the eighth lens is a convex surface;

[0008] The optical imaging device satisfies the relationship:

[0009] 0.1<T34 / f4<0.25;

[0010] 0.60<d02s / R7<1.30;

[0011] 0<d02s / R6≤0.40;

[0012] Among them, T34 is the air gap between the third lens and the fourth lens, f4 is the focal length of the fourth lens; d02s is the inner diameter of the object side surface of the second lens barrel, R6 is the curvature radius of the image side surface of the third lens, and R7 is the curvature radius of the object side surface of the fourth lens.

[0013] In some embodiments, the image side of the first lens barrel is buckled with the object side of the second lens barrel, and the first lens barrel and the second lens barrel satisfy the relationship:

[0014] L1+L2>L;

[0015] Wherein, L1 is the maximum height of the first lens barrel, L2 is the maximum height of the second lens barrel, and L is the maximum height of the entire lens barrel assembly.

[0016] In some embodiments, the optical imaging device satisfies the relationship:

[0017] 0.75<d01m / d02s≤1.9;

[0018] Wherein, d02s is the inner diameter of the object side surface of the second lens barrel, and d01m is the inner diameter of the image side surface of the first lens barrel.

[0019] In some embodiments, the optical imaging device satisfies the relationship:

[0020] 0.6<(d01s-d01m) / L1<0.75;

[0021] Wherein, d01s is the inner diameter of the object side surface of the first lens barrel, d01m is the inner diameter of the image side surface of the first lens barrel, and L1 is the maximum height of the first lens barrel.

[0022] In some embodiments, the optical imaging device satisfies the relationship:

[0023] 0<(d01s-d02m) / f<1.1;

[0024] Among them, d01s is the inner diameter of the object side of the first lens barrel, d02m is the inner diameter of the image side of the second lens barrel, and f is the effective focal length of the optical imaging device.

[0025] In some embodiments, the optical imaging device further includes a first spacer element, the first spacer element is disposed between the first lens and the second lens, and the first spacer element at least partially contacts the image side surface of the first lens; the optical imaging device satisfies the relationship:

[0026] -0.55<EP011 / f1<-0.4;

[0027] Wherein, EP011 is the on-axis distance from the object side surface of the first lens barrel to the object side surface of the first spacing element, and f1 is the effective focal length of the first lens.

[0028] In some embodiments, the optical imaging device satisfies the relationship:

[0029] 3.7<(d01s-d1s) / CT1<4.7;

[0030] Wherein, d01s is the inner diameter of the object side surface of the first lens barrel, d1s is the inner diameter of the object side surface of the first spacing element, and CT1 is the center thickness of the first lens.

[0031] In some embodiments, the optical imaging device satisfies the relationship:

[0032] 0.25<d1s / (f2-f1)≤0.45;

[0033] Wherein, d1s is the object-side inner diameter of the first spacer element, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.

[0034] In some embodiments, the optical imaging device further includes a first spacing element and a second spacing element, the first spacing element is disposed between the first lens and the second lens, and the first spacing element at least partially contacts the image side surface of the first lens; the second spacing element is disposed between the second lens and the third lens, and the second spacing element at least partially contacts the image side surface of the second lens; the optical imaging device satisfies the relationship:

[0035] 0.1<(D1m-D2s) / f2≤0.6;

[0036] Wherein, D2s is the object side outer diameter of the second spacer element, D1m is the image side outer diameter of the first spacer element, and f2 is the effective focal length of the second lens.

[0037] In some embodiments, the optical imaging device satisfies the relationship:

[0038] -0.80<d1m / R3<-0.40;

[0039] -1.55<d2s / R4<-0.70;

[0040] Among them, d1m is the inner diameter of the image side of the first spacing element, d2s is the inner diameter of the object side of the second spacing element, R3 is the curvature radius of the object side of the second lens, and R4 is the curvature radius of the image side of the second lens.

[0041] In some embodiments, the optical imaging device satisfies the relationship:

[0042] 1.3≤(EP011+EP12) / (CT1+CT2)≤1.45;

[0043] Among them, EP011 is the on-axis distance from the object side surface of the first lens barrel to the object side surface of the first spacing element, EP12 is the on-axis distance from the image side surface of the first spacing element to the object side surface of the second spacing element, CT1 is the center thickness of the first lens, and CT2 is the center thickness of the second lens.

[0044] In some embodiments, the optical imaging device satisfies the relationship:

[0045] 0.35<d2s / f2≤0.65;

[0046] 0<d2m / f3≤0.45;

[0047] Among them, d2s is the inner diameter of the second spacer element on the object side, d2m is the inner diameter of the second spacer element on the image side, f2 is the effective focal length of the second lens, and f3 is the effective focal length of the third lens.

[0048] Since the present application imposes strict restrictions on the air gap between lenses and the focal length of the lenses, if the design tolerance is too harsh, it may lead to precision deviations in the actual production and assembly process. Some minor manufacturing errors (such as slight changes in the air gap) will cause fluctuations in system performance, thereby affecting the image quality. Such assembly errors may aggravate the non-ideal performance of the optical system, especially under the conditions of wide field angle and small F number, the optical system has a small tolerance space, which is easy to cause optical error accumulation. Under the wide-angle design of the present application, the larger field angle and smaller F number will cause the defocus curve of the lens to present a more complex nonlinear behavior, and because of the tightness of the lens combination design, as the optical axis defocuses, the MTF curve may show significant distortion or unfocusing. Specifically, the effect of defocus is particularly prominent under a wide field of view, and the angle change of the light will cause the imaging of each image point to shift, the MTF value will decrease, and the overall clarity of the picture will be poor. In this design, the limitation of T34 / f4 in the present application may cause the optical system to be more sensitive to defocus errors, resulting in large differences in image quality at different focal lengths, and it is difficult to maintain high-quality imaging effects.

[0049] The optical imaging device of the present application controls the geometric matching between the lenses by optimizing the relationship between the inner diameter d02s of the lens barrel and the lens curvature radius R6 and R7 during the design process, and can reduce the air gap change caused by improper lens barrel design, thereby reducing the assembly error. Through the above-mentioned geometric matching relationship, it is ensured that the lens has good compatibility during the actual manufacturing and assembly process, so that the assembly accuracy and stability of the optical system can be improved. By optimizing the relationship between the inner diameter of the lens barrel and the lens curvature, the deviation phenomenon of the MTF curve during defocus can be reduced during the design process. By using the good matching of the proficient inner diameter and the lens curvature, the defocus behavior of each lens under the condition of a wide field angle can be more stable. Especially in the design of a larger field angle and a smaller F number, by optimizing the above-mentioned parameters, it is helpful to suppress the negative impact of the defocus effect on the imaging quality, reduce the fluctuation of the MTF value, and make the defocus curve more concentrated and stable. When the design parameters exceed the scope of the above-mentioned relationship, the defocus curve of the optical system will no longer be concentrated, resulting in greater aberrations and distortion. Especially when far away from the best focal length, the decline of the MTF curve will be more significant, resulting in more obvious image blur or defocus phenomenon.

[0050] The optical imaging device of the present application achieves a balance between a larger market angle and a smaller F number by optimizing the combination of lenses and the reasonable design of lens spacing. By constraining the size, distance and geometric relationship between the lens and the lens element through multiple formulas, it can provide excellent optical performance while ensuring that the optical system meets the requirements of compactness and miniaturization; it can not only ensure the advantages in optical transmission efficiency, aberration control, optical distortion and astigmatism suppression, but also effectively improve the mechanical stability and temperature adaptability of the optical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic diagram showing the dimensions of an optical imaging device according to an optional embodiment of the present invention is shown;

[0052] Figure 2A A schematic structural diagram of an optical imaging device provided by a first example of a first embodiment of the present invention is shown;

[0053] Figure 2B A schematic diagram showing the structure of an optical imaging device provided by a second example of the first embodiment of the present invention is shown;

[0054] Figure 2C A schematic structural diagram of an optical imaging device provided by a third example of the first embodiment of the present invention is shown;

[0055] Figure 3A An on-axis chromatic aberration curve diagram of the optical imaging device according to the first embodiment of the present invention is shown;

[0056] Figure 3B shows an astigmatism curve diagram of the optical imaging device of the first embodiment of the present invention;

[0057] Figure 3C A distortion curve diagram of the optical imaging device according to the first embodiment of the present invention is shown;

[0058] Figure 4A A schematic structural diagram of an optical imaging device provided by a fourth example of the second embodiment of the present invention is shown;

[0059] Figure 4B A schematic structural diagram of an optical imaging device provided by a fifth example of the second embodiment of the present invention is shown;

[0060] Figure 4C A schematic diagram showing the structure of an optical imaging device provided by a sixth example of the second embodiment of the present invention is shown;

[0061] Figure 5A An axial chromatic aberration curve diagram of an optical imaging device according to a second embodiment of the present invention is shown;

[0062] Figure 5B shows an astigmatism curve diagram of an optical imaging device according to a second embodiment of the present invention;

[0063] Figure 5C A distortion curve diagram of an optical imaging device according to a second embodiment of the present invention is shown;

[0064] Fig. 6A A schematic diagram showing the structure of an optical imaging device provided by a seventh example of the third embodiment of the present invention is shown;

[0065] Figure 6B A schematic structural diagram of an optical imaging device provided by an eighth example of the third embodiment of the present invention is shown;

[0066] Figure 6C A schematic diagram showing the structure of an optical imaging device provided by a ninth example of the third embodiment of the present invention;

[0067] Fig. 7A An on-axis chromatic aberration curve diagram of an optical imaging device according to a third embodiment of the present invention is shown;

[0068] Figure 7B shows an astigmatism curve diagram of an optical imaging device according to a third embodiment of the present invention;

[0069] Figure 7C A distortion curve diagram of an optical imaging device according to a third embodiment of the present invention is shown;

[0070] Fig. 8A A defocus curve diagram when the optical imaging device of an optional embodiment of the present invention satisfies T34 / f4=0.17, d02s / R7=0.65 and d02s / R6=0.03 is shown;

[0071] Figure 8B A defocus curve diagram when the optical imaging device of an optional embodiment of the present invention satisfies the relationship T34 / f4=0.17, d02s / R7=1.5 and d02s / R6=0.01 is shown;

[0072] Figure 8C A defocus curve diagram is shown when an optical imaging device of an optional embodiment of the present invention satisfies the relationship T34 / f4=0.17, d02s / R7=0.5 and d02s / R6=0.5.

[0073] Figure markings: P01, first lens barrel; P02, second lens barrel; E1, first lens; E2, second lens; E3, third lens; E4, fourth lens; E5, fifth lens; E6, sixth lens; E7, seventh lens; E8, eighth lens; P1, first spacing element; P2, second spacing element; P2b, second auxiliary spacing element; P4, fourth spacing element; P5, fifth spacing element; P6, sixth spacing element; P6b, sixth front auxiliary spacing element; P6c, sixth rear auxiliary spacing element; P7, seventh spacing element; P7b, seventh auxiliary spacing element. DETAILED DESCRIPTION

[0074] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0075] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0076] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0077] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0078] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0079] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0080] Based on the problem that under the conditions of wide field angle and large aperture of the existing eight-piece lens, the assembly error has a great impact on the optical system due to the small error tolerance space of the optical system, the present application provides an optical imaging device, which achieves a balance between a larger field angle and a smaller F number by optimizing the combination of lenses and the reasonable design of lens spacing. By constraining the size, distance and geometric relationship between the lens and the visible elements by multiple formulas, it is possible to provide excellent optical performance while ensuring that the optical system meets the requirements of compactness and miniaturization; it can not only ensure the advantages in optical transmission efficiency, aberration control, optical distortion and astigmatism suppression, but also effectively improve the mechanical stability and temperature adaptability of the optical system.

[0081] For details, please refer to Figure 1 and Figure 2A The optical imaging device of the present application may include a lens barrel assembly and a lens assembly, wherein the lens barrel assembly includes a first lens barrel and a second lens barrel which are sequentially arranged, and the inner annular surface of the first lens barrel and the inner annular surface of the second lens barrel are both stepped. The lens assembly includes a first lens with negative optical power, a second lens with positive optical power, a third lens with positive optical power, a fourth lens with positive optical power, a fifth lens with negative optical power, a sixth lens with positive optical power, a seventh lens with negative optical power, and an eighth lens with positive optical power which are sequentially arranged along the optical axis from the object side to the image side; the first lens, the second lens, and the third lens are arranged in the first lens barrel, and the fourth lens, the fifth lens, the sixth lens, the seventh lens, and the eighth lens are arranged in the second lens barrel. The object side surface of the first lens is concave; the object side surface and image side surface of the second lens are concave and convex respectively; the object side surface and image side surface of the third lens are convex and concave respectively; the object side surface of the fourth lens is convex; the object side surface and image side surface of the fifth lens are convex and concave respectively; the image side surface of the sixth lens is convex; the image side surface of the seventh lens is concave; and the image side surface of the eighth lens is convex.

[0082] The optical imaging device of the present application satisfies the relationship 0.1<T34 / f4<0.25, wherein T34 is the air gap between the third lens and the fourth lens, and f4 is the focal length of the fourth lens. The air gap between the lenses and the focal length of the lenses are designed according to the above relationship to ensure that the optical imaging device can achieve a balance between a larger field of view and a smaller F number, and to ensure that the system can provide excellent optical performance while meeting the requirements of compactness and miniaturization.

[0083] Since the present application imposes strict restrictions on the air gap between lenses and the focal length of the lenses, if the design tolerance is too harsh, it may lead to precision deviations in the actual production and assembly process. Some minor manufacturing errors (such as slight changes in the air gap) will cause fluctuations in system performance, thereby affecting the image quality. Such assembly errors may aggravate the non-ideal performance of the optical system, especially under the conditions of wide field angle and small F number, the optical system has a small tolerance space, which is easy to cause optical error accumulation. Under the wide-angle design of the present application, the larger field angle and smaller F number will cause the defocus curve of the lens to present a more complex nonlinear behavior, and because of the tightness of the lens combination design, as the optical axis defocuses, the MTF curve may show significant distortion or unfocusing. Specifically, the effect of defocus is particularly prominent under a wide field of view, and the angle change of the light will cause the imaging of each image point to shift, the MTF value will decrease, and the overall clarity of the picture will be poor. In this design, the limitation of T34 / f4 in the present application may cause the optical system to be more sensitive to defocus errors, resulting in large differences in image quality at different focal lengths, and it is difficult to maintain high-quality imaging effects.

[0084] Therefore, the optical imaging device of the present application also satisfies the relationship 0.60<d02s / R7<1.30 and 0<d02s / R6≤0.40; wherein d02s is the inner diameter of the object side of the second lens barrel, R6 is the radius of curvature of the image side of the third lens, and R7 is the radius of curvature of the object side of the fourth lens. The optical imaging device of the present application is designed according to the above relationship. By optimizing the relationship between the inner diameter d02s of the lens barrel and the lens curvature radii R6 and R7 during the design process, the geometric matching between the lenses is controlled, and the air gap change caused by improper lens barrel design can be reduced, thereby reducing the assembly error. Through the above geometric matching relationship, it is ensured that the lens has good compatibility during the actual manufacturing and assembly process, so that the assembly accuracy and stability of the optical system can be improved. By optimizing the relationship between the inner diameter of the lens barrel and the curvature of the lens, the deviation of the MTF curve during defocusing can be reduced during the design process. By mastering the good matching of the inner diameter and the lens curvature, the defocusing behavior of each lens under the condition of a wide field of view angle can be more stable. Especially in the design of larger field angle and smaller F number, by optimizing the above parameters, it is helpful to suppress the negative impact of defocus effect on image quality, reduce the fluctuation of MTF value, and make the defocus curve more concentrated and stable. When the design parameters exceed the range of the above relationship, the defocus curve of the optical system will no longer be concentrated, resulting in greater aberration and distortion. Especially when far away from the best focal length, the decline of MTF curve will be more significant, resulting in more obvious image blur or out of focus.

[0085] For example, Fig. 8A , Figure 8B and Figure 8C As shown, when the optical imaging device of the present application satisfies the relationship T34 / f4=0.17, d02s / R7=0.65 and d02s / R6=0.03, its design parameters are in line with the range defined in the present application, and its defocus curve is relatively concentrated and stable. When the optical imaging device of the present application satisfies the relationship T34 / f4=0.17, d02s / R7=1.5 and d02s / R6=0.01, its design parameters do not meet the range defined in the present application, and the d02S / R7 value is too large, resulting in a mismatch in the relative curvature between the lenses, which increases the defocus of the optical system. When the optical imaging device of the present application satisfies the relationship T34 / f4=0.17, d02s / R7=0.5 and d02s / R6=0.5, its design parameters do not meet the range defined in the present application, and the d02s / R6 value is too large, resulting in a sudden change in beam deflection and a lack of focus, which increases the defocus of the optical system.

[0086] Alternatively, if Figure 1 and Figure 2AAs shown, in some embodiments, the image side of the first lens barrel of the present application is buckled with the object side of the second lens barrel, and the first lens barrel and the second lens barrel satisfy the relationship L1+L2>L, wherein L1 is the maximum height of the first lens barrel, L2 is the maximum height of the second lens barrel, and L is the maximum height of the entire lens barrel assembly.

[0087] Such a setting ensures that there is sufficient space and proper physical contact between the lens barrels, reduces possible errors during assembly, ensures the relative position and axial alignment of each lens, helps avoid unnecessary optical errors during the assembly process, and thus improves the stability and overall accuracy of the system. By snapping the first lens barrel and the second lens barrel together, the optical axis of the lens assembly is kept consistent, reducing the displacement and misalignment between the lens barrels, thereby optimizing the transmission path of the light beam. In this way, astigmatism and other optical distortions can be reduced, especially in the design of wide-angle lenses, which can ensure the imaging quality at a large field of view. By ensuring that L1+L2>L, the design space can be avoided from being too compact, leaving enough room for adjustment to ensure the optimization of optical performance.

[0088] Alternatively, if Figure 1 and Figure 2A As shown, in some embodiments, the optical imaging device of the present application satisfies the relationship: 0.75<d01m / d02s≤1.9; wherein d02s is the inner diameter of the object side of the second lens barrel, and d01m is the inner diameter of the image side of the first lens barrel.

[0089] In this way, by controlling the ratio of the inner diameters of the first lens barrel and the second lens barrel to be within a reasonable range, it is possible to ensure that the inner diameters of the first lens barrel and the second lens barrel match, which helps to smoothly transmit the light beam in the lens assembly and avoid obstruction of the light path or unnecessary refraction. Especially for wide-angle lens design, mismatched inner diameters may lead to non-uniformity of light beam transmission, increase astigmatism and other optical distortions. Therefore, ensuring that the inner diameter ratio is within this range helps to reduce these optical problems and optimize imaging quality.

[0090] A large inner diameter difference may cause a drastic change in the transmission path of the light beam between the object side and the image side, thereby causing astigmatism and other optical distortions. Therefore, in some embodiments, the optical imaging device of the present application satisfies the relationship: 0.6<(d01s-d01m) / L1<0.75; wherein d01s is the inner diameter of the object side of the first lens barrel, d01m is the inner diameter of the image side of the first lens barrel, and L1 is the maximum height of the first lens barrel.

[0091] By setting the difference between the inner diameter d01s of the object side and the inner diameter d01m of the image side of the lens barrel within a suitable range, the astigmatism problem caused by too large or too small inner diameter difference can be avoided. By designing an appropriate inner diameter difference, the irregularity of the optical path can be reduced, thereby optimizing the imaging quality.

[0092] The generation of astigmatism is often related to the non-uniform refraction of the light beam and the asymmetry of the optical path. Too large an inner diameter difference may lead to inconsistent focusing degrees of light at different positions, resulting in uneven imaging. Therefore, in some embodiments, the optical imaging device of the present application satisfies the relationship: 0<(d01s-d02m) / f<1.1; wherein d01s is the inner diameter of the object side of the first lens barrel, d02m is the inner diameter of the image side of the second lens barrel, and f is the effective focal length of the optical imaging device.

[0093] In this way, by controlling the reasonable ratio of the difference in the inner diameters of the first lens barrel and the second lens barrel, the astigmatism and other optical distortions in the optical system can be reduced to a great extent. According to the above relationship, the ratio of the difference in the inner diameters of the first lens barrel and the second lens barrel to the focal length is within a suitable range, which can make the light beam more evenly transmitted in the entire system, thereby reducing astigmatism and distortion and improving the overall imaging quality of the system.

[0094] Alternatively, if Figure 1 and Figure 2A As shown, in some embodiments, the optical imaging device of the present application further includes a first spacer element, which is arranged between the first lens and the second lens, and the first spacer element is at least partially in contact with the image side surface of the first lens; the optical imaging device satisfies the relationship: -0.55<EP011 / f1<-0.4; wherein EP011 is the axial distance from the object side surface of the first lens barrel to the object side surface of the first spacer element, and f1 is the effective focal length of the first lens.

[0095] In this way, by controlling the appropriate spacing between the first spacing element and the lens, the optical axis alignment and overall geometric accuracy of the optical system are facilitated. By designing the distance between the first spacing element and the first lens according to the above relationship, the precise relative position between the optical elements can be ensured, and the optical axis offset caused by tolerance deviation during the assembly process can be avoided. In addition, the stricter position requirements help improve the assembly accuracy, reduce the optical error caused by asymmetric assembly, and ensure the stability of the optical performance of the system.

[0096] The thickness of the lens and the difference in the inner diameter of the lens barrel and the spacer elements have an impact on the thermal stability of the optical system. When the temperature changes, the thermal expansion of the lens, lens barrel and spacer elements will affect the relative position of the optical elements. Therefore, if Figure 1 and Figure 2AAs shown, in some embodiments, the optical imaging device of the present application satisfies the relationship: 3.7<(d01s-d1s) / CT1<4.7; wherein d01s is the inner diameter of the object side of the first lens barrel, d1s is the inner diameter of the object side of the first spacing element, and CT1 is the center thickness of the first lens.

[0097] In this way, by designing the inner diameter of the object side surface of the first lens barrel, the object side inner diameter of the first spacing element, and the center thickness of the first lens according to the above relationship, the geometric shape of the optical system under temperature changes can be kept stable, and the optical error caused by thermal expansion can be reduced, thereby improving the thermal stability and adaptability of the optical system.

[0098] An inner diameter that is too large or too small for the spacing element will affect the transmission efficiency of the light beam. An inner diameter that is too large may cause the light beam path to be too long, increasing the chances of scattering and reflection, thereby reducing the light transmission efficiency of the system; while an inner diameter that is too small may limit the propagation space of the light, resulting in the light beam failing to fully utilize the function of the optical element during the transmission process. Therefore, in some embodiments, the optical imaging device of the present application satisfies the relationship: 0.25<d1s / (f2-f1)≤0.45; wherein d1s is the object side inner diameter of the first spacing element, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.

[0099] In this way, by optimizing the relationship between the size of the first spacing element and the focal length difference between the two lenses, the optical efficiency of the system can be affected. By reasonably controlling the ratio of the object side inner diameter of the first spacing element to the effective focal length difference between the first lens and the second lens, the transmission process of the light beam between the two lenses and the spacing element can be ensured, unnecessary light loss can be reduced as much as possible, the transmission efficiency of the optical system can be maximized, and the efficient coordination of each optical element in transmitting the light beam can be ensured.

[0100] Alternatively, if Figure 1 and Figure 2A As shown, in some embodiments, the optical imaging device of the present application further includes a first spacing element and a second spacing element, the first spacing element is arranged between the first lens and the second lens, and the first spacing element is at least partially in contact with the image side surface of the first lens; the second spacing element is arranged between the second lens and the third lens, and the second spacing element is at least partially in contact with the image side surface of the second lens; the optical imaging device satisfies the relationship: 0.1<(D1m-D2s) / f2≤0.6; wherein D2s is the object side outer diameter of the second spacing element, D1m is the image side outer diameter of the first spacing element, and f2 is the effective focal length of the second lens.

[0101] In this way, by controlling the ratio of the outer diameter difference D1m-D2s between the second spacing element and the first spacing element and the focal length f2 of the second lens, the propagation path of the light beam when passing through the second lens and the second spacing element can be affected. By designing a reasonable outer diameter difference ratio, it helps to ensure the focusing effect of the light beam after passing through the second lens and reduce the bending or scattering of the light. If the ratio is too small, the second spacing element may be too large and the light beam path may be too compact, thereby increasing aberrations and other optical distortions; if the ratio is too large, it may affect the transmission efficiency of the light beam and cause the optical performance of the system to deteriorate. By ensuring that the ratio is within a reasonable range, the propagation of the light path can be optimized and the optical focusing stability of the system can be ensured.

[0102] Alternatively, if Figure 1 and Figure 2A As shown, in some embodiments, the optical imaging device of the present application satisfies the relationship: -0.80<d1m / R3<-0.40;

[0103] -1.55<d2s / R4<-0.70; wherein, d1m is the inner diameter of the image side of the first spacing element, d2s is the inner diameter of the object side of the second spacing element, R3 is the curvature radius of the object side of the second lens, and R4 is the curvature radius of the image side of the second lens.

[0104] In this way, the aberration caused by astigmatism is usually closely related to the geometric configuration between the optical elements. By controlling the relationship between the inner diameter of the first spacing element and the second spacing element and the radius of curvature of the lens, the geometric layout of the optical system can be optimized, and the optical distortion caused by optical axis offset, beam asymmetry or uneven refraction can be reduced. Too large an inner diameter difference may cause the optical axis to be misaligned, affecting the focusing effect of the lens; too small an inner diameter difference may cause additional geometric distortion when the beam passes through. By designing a reasonable ratio, it is helpful to reduce such optical distortion and ensure that the imaging system can still maintain small astigmatism and low geometric distortion at high resolution.

[0105] In the design and manufacture of optical systems, the relative positions of the lens barrel, lenses, and spacer elements must be kept precise to ensure the optical performance of the system. Figure 1 and Figure 2A As shown, in some embodiments, the optical imaging device of the present application satisfies the relationship: 1.3≤(EP011+EP12) / (CT1+CT2)≤1.45; wherein, EP011 is the axial distance from the object side surface of the first lens barrel to the object side surface of the first spacing element, EP12 is the axial distance from the image side surface of the first spacing element to the object side surface of the second spacing element, CT1 is the center thickness of the first lens, and CT2 is the center thickness of the second lens.

[0106] In this way, controlling a reasonable ratio helps provide clear dimensional control during the manufacturing and assembly process, reducing optical deviations caused by assembly errors. Too large a ratio may make the relative position of the spacing elements unstable, increasing the difficulty of the assembly process; while too small a ratio may cause the spacing of the lenses to be too small, increasing assembly errors. According to the above relationship, the ratio (EP011+EP12) / (CT1+CT2) can be controlled to accurately locate the position of the components during the assembly process, improve assembly accuracy, and reduce errors in the optical system.

[0107] Temperature changes cause thermal expansion of optical components, which can affect the focal length and optical path of the system. Figure 1 and Figure 2A As shown, in some embodiments, the optical imaging device of the present application satisfies the relationship: 0.35<d2s / f2≤0.65;

[0108] 0<-d2m / f3≤0.45; wherein, d2s is the object side inner diameter of the second spacing element, d2m is the image side inner diameter of the second spacing element, f2 is the effective focal length of the second lens, and f3 is the effective focal length of the third lens.

[0109] By setting this up and controlling the ratio d2s / f2-d2m / f3 according to the above relationship, the influence of temperature change on optical performance can be reduced, ensuring that the system can maintain stable optical performance under different temperature environments. The appropriate ratio of the inner diameter of the spacer element and the focal length of the lens helps to reduce the geometric deformation caused by thermal expansion, ensure the stability of the focus and the imaging accuracy, and improve the thermal stability of the system.

[0110] Specific embodiments of the optical imaging device applicable to the above-mentioned embodiments are further described below with reference to the accompanying drawings.

[0111] like Figure 2A , Figure 2B and Figure 2C The first example, the second example and the third example of the first embodiment of the present application are shown. In the first embodiment of the present application, the optical imaging device includes a lens barrel assembly and a lens assembly. The lens barrel assembly includes a first lens barrel P01 and a second lens barrel P02 arranged in sequence. The lens assembly includes a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8 arranged in sequence from the object side to the image side. The first lens E1, the second lens E2 and the third lens E3 are arranged in the first lens barrel P01, and the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7 and the eighth lens E8 are arranged in the second lens barrel P02.

[0112] The optical imaging device also includes a first spacing element P1, a second spacing element P2, a second auxiliary spacing element P2b, a fourth spacing element P4, a fifth spacing element P5, a sixth spacing element P6, a sixth front auxiliary spacing element P6b and a seventh spacing element P7. The first spacing element P1 is disposed between the first lens E1 and the second lens E2, and the first spacing element P1 is at least partially in contact with the image side surface of the first lens E1; the second spacing element P2 is disposed between the second lens E2 and the third lens E3, and the second spacing element P2 is at least partially in contact with the image side surface of the second lens E2; the second auxiliary spacing element P2b is disposed between the second spacing element P2 and the third lens E3, and is at least partially in contact with the image side surface of the second spacing element P2; the fourth spacing element P4 is disposed between the fourth lens E4 and the fifth lens E5, and is at least partially in contact with the image side surface of the fourth lens E4. The fifth spacing element P5 is disposed between the fifth lens E5 and the sixth lens E6, and at least partially contacts the image side surface of the fifth lens E5; the sixth spacing element P6 is disposed between the sixth lens E6 and the seventh lens E7, and at least partially contacts the image side surface of the sixth lens E6; the sixth front auxiliary spacing element P6b is disposed between the sixth spacing element P6 and the seventh lens E7, and at least partially contacts the image side surface of the sixth spacing element P6; the seventh spacing element P7 is disposed between the seventh lens E7 and the eighth lens E8, and the seventh spacing element P7 at least partially contacts the image side surface of the seventh lens E7.

[0113] Among them, the first lens E1 has negative focal power, and the object side surface and image side surface of the first lens E1 are both concave surfaces. The second lens E2 has positive focal power, and the object side surface and image side surface of the second lens E2 are concave and convex surfaces respectively. The third lens E3 has positive focal power, and the object side surface and image side surface of the third lens E3 are convex and concave surfaces respectively. The fourth lens E4 has positive focal power, and the object side surface and image side surface of the fourth lens E4 are both convex surfaces. The fifth lens E5 has negative focal power, and the object side surface and image side surface of the fifth lens E5 are convex and concave surfaces respectively. The sixth lens E6 has positive focal power, and the object side surface and image side surface of the sixth lens E6 are concave and convex surfaces respectively. The seventh lens E7 has negative focal power, and the object side surface and image side surface of the seventh lens E7 are convex and concave surfaces respectively. The eighth lens E8 has positive focal power, and the object side surface and image side surface of the eighth lens E8 are concave and convex surfaces respectively.

[0114] Table 1 shows a basic parameter table of the lens of the optical imaging device of the first embodiment, wherein the units of the radius of curvature and thickness are both millimeters (mm), and Table 2 shows a high-order coefficient table of the aspherical mirror surface of the optical imaging device of the first embodiment.

[0115] Table 1: Basic parameters of the lens of the optical imaging device of the first embodiment

[0116]

[0117] Table 2: Table of high-order coefficients of the aspherical mirror surface of the optical imaging device of the first embodiment

[0118]

[0119] In the first embodiment, the object side surface and the image side surface of any lens of the first lens E1 to the eighth lens E8 are both aspherical surfaces, and the surface shape x of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0120]

[0121] Wherein, x is the distance from the vertex of the aspheric surface to the height h along the optical axis: c is the paraxial curvature of the aspheric surface, c=1R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 1 above): k is the cone coefficient: Ai is the correction coefficient of the i-th order of the aspheric surface. Table 2 below gives the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 that can be used for each aspheric mirror surface S1-S14 in the first embodiment.

[0122] Figure 3A shows the axial chromatic aberration curve of the optical imaging device of the first embodiment, Figure 3B The astigmatism curve of the optical imaging device of the first embodiment is shown. Figure 3C The distortion curve of the optical imaging device of the first embodiment is shown. FIG. 3A to FIG. 3C It can be seen that the optical imaging device provided in the first embodiment has good imaging quality.

[0123] like Figure 4A , Figure 4B and Figure 4C The first example, the second example and the third example of the second embodiment of the present application are shown. In the second embodiment of the present application, the optical imaging device includes a lens barrel assembly and a lens assembly. The lens barrel assembly includes a first lens barrel P01 and a second lens barrel P02 arranged in sequence. The lens assembly includes a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8 arranged in sequence from the object side to the image side. The first lens E1, the second lens E2 and the third lens E3 are arranged in the first lens barrel P01, and the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7 and the eighth lens E8 are arranged in the second lens barrel P02.

[0124] The optical imaging device also includes a first spacing element P1, a second spacing element P2, a fourth spacing element P4, a fifth spacing element P5, a sixth spacing element P6, a seventh spacing element P7 and a seventh auxiliary spacing element P7b. The first spacing element P1 is disposed between the first lens E1 and the second lens E2, and the first spacing element P1 is at least partially in contact with the image side surface of the first lens E1; the second spacing element P2 is disposed between the second lens E2 and the third lens E3, and the second spacing element P2 is at least partially in contact with the image side surface of the second lens E2; the fourth spacing element P4 is disposed between the fourth lens E4 and the fifth lens E5, and is at least partially in contact with the image side surface of the fourth lens E4; the fifth spacing element P5 is disposed between the fifth lens E5 and the sixth lens E6, and is at least partially in contact with the image side surface of the fifth lens E5; The sixth spacing element P6 is arranged between the sixth lens E6 and the seventh lens E7, and at least partially contacts the image side surface of the sixth lens E6; the sixth front auxiliary spacing element P6b is arranged between the sixth spacing element P6 and the seventh lens E7, and at least partially contacts the image side surface of the sixth spacing element P6; the seventh spacing element P7 is arranged between the seventh lens E7 and the eighth lens E8, and the seventh spacing element P7 at least partially contacts the image side surface of the seventh lens E7; the seventh auxiliary spacing element P7b is between the seventh spacing element P7 and the eighth lens E8, and at least partially contacts the image side surface of the seventh spacing element P7.

[0125] Among them, the first lens E1 has negative focal power, and the object side surface and image side surface of the first lens E1 are concave and convex respectively. The second lens E2 has positive focal power, and the object side surface and image side surface of the second lens E2 are concave and convex respectively. The third lens E3 has positive focal power, and the object side surface and image side surface of the third lens E3 are convex and concave respectively. The fourth lens E4 has positive focal power, and the object side surface and image side surface of the fourth lens E4 are both convex. The fifth lens E5 has negative focal power, and the object side surface and image side surface of the fifth lens E5 are convex and concave respectively. The sixth lens E6 has positive focal power, and the object side surface and image side surface of the sixth lens E6 are concave and convex respectively. The seventh lens E7 has negative focal power, and the object side surface and image side surface of the seventh lens E7 are both concave. The eighth lens E8 has positive focal power, and the object side surface and image side surface of the eighth lens E8 are both convex.

[0126] Table 3 shows a basic parameter table of the lens of the optical imaging device of the second embodiment, wherein the units of the radius of curvature and thickness are both millimeters (mm), and Table 4 shows a high-order coefficient table of the aspherical mirror surface of the optical imaging device of the second embodiment.

[0127] Table 3: Basic parameters of the lens of the optical imaging device of the second embodiment

[0128]

[0129] Table 4: Table of high-order coefficients of the aspherical mirror surface of the optical imaging device of the second embodiment

[0130]

[0131] In the second embodiment, the object side surface and the image side surface of any lens among the first lens E1 to the eighth lens E8 are both aspherical surfaces, and the surface shape x of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0132]

[0133] Wherein, x is the distance from the vertex of the aspheric surface when the aspheric surface is at a height of h along the optical axis: c is the paraxial curvature of the aspheric surface, c=1R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 3 above): k is the cone coefficient: Ai is the correction coefficient of the i-th order of the aspheric surface. Table 4 below gives the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 that can be used for each aspheric mirror surface S1-S14 in the second embodiment.

[0134] Figure 5A shows the axial chromatic aberration curve of the optical imaging device of the second embodiment, Figure 5B The astigmatism curve of the optical imaging device of the second embodiment is shown. Figure 5C The distortion curve of the optical imaging device of the second embodiment is shown. FIG. 5A to FIG. 5C It can be seen that the optical imaging device provided in the second embodiment has good imaging quality.

[0135] like Fig. 6A , Figure 6B and Figure 6C The first example, the second example and the third example of the third embodiment of the present application are shown. In the third embodiment of the present application, the optical imaging device includes a lens barrel assembly and a lens assembly. The lens barrel assembly includes a first lens barrel P01 and a second lens barrel P02 arranged in sequence. The lens assembly includes a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a sixth lens E6, a seventh lens E7 and an eighth lens E8 arranged in sequence from the object side to the image side. The first lens E1, the second lens E2 and the third lens E3 are arranged in the first lens barrel P01, and the fourth lens E4, the fifth lens E5, the sixth lens E6, the seventh lens E7 and the eighth lens E8 are arranged in the second lens barrel P02.

[0136] The optical imaging device also includes a first spacing element P1, a second spacing element P2, a fourth spacing element P4, a fifth spacing element P5, a sixth spacing element P6, a sixth front auxiliary spacing element P6b, a sixth rear auxiliary spacing element P6c and a seventh spacing element P7. The first spacing element P1 is disposed between the first lens E1 and the second lens E2, and the first spacing element P1 is at least partially in contact with the image side surface of the first lens E1; the second spacing element P2 is disposed between the second lens E2 and the third lens E3, and the second spacing element P2 is at least partially in contact with the image side surface of the second lens E2; the fourth spacing element P4 is disposed between the fourth lens E4 and the fifth lens E5, and is at least partially in contact with the image side surface of the fourth lens E4; the fifth spacing element P5 is disposed between the fifth lens E5 and the sixth lens E6, and is at least partially in contact with the image side surface of the fifth lens E5; the sixth spacing element The sixth lens E6 and the seventh lens E7 are provided with the sixth auxiliary spacer element P6, and at least partially contact the image side surface of the sixth lens E6; the sixth front auxiliary spacer element P6b is provided between the sixth spacer element P6 and the seventh lens E7, and at least partially contact the image side surface of the sixth spacer element P6; the sixth rear auxiliary spacer element P6c is provided between the sixth front auxiliary spacer element P6b and the seventh lens E7, and at least partially contact the image side surface of the sixth front auxiliary spacer element P6b; the seventh spacer element P7 is provided between the seventh lens E7 and the eighth lens E8, and the seventh spacer element P7 at least partially contact the image side surface of the seventh lens E7.

[0137] Among them, the first lens E1 has negative focal power, and the object side surface and image side surface of the first lens E1 are both concave surfaces. The second lens E2 has positive focal power, and the object side surface and image side surface of the second lens E2 are concave and convex surfaces respectively. The third lens E3 has positive focal power, and the object side surface and image side surface of the third lens E3 are convex and concave surfaces respectively. The fourth lens E4 has positive focal power, and the object side surface and image side surface of the fourth lens E4 are convex and concave surfaces respectively. The fifth lens E5 has negative focal power, and the object side surface and image side surface of the fifth lens E5 are convex and concave surfaces respectively. The sixth lens E6 has positive focal power, and the object side surface and image side surface of the sixth lens E6 are both convex surfaces. The seventh lens E7 has negative focal power, and the object side surface and image side surface of the seventh lens E7 are convex and concave surfaces respectively. The eighth lens E8 has positive focal power, and the object side surface and image side surface of the eighth lens E8 are both convex surfaces.

[0138] Table 5 shows a basic parameter table of the lens of the optical imaging device of the third embodiment, wherein the units of the radius of curvature and thickness are both millimeters (mm), and Table 6 shows a high-order coefficient table of the aspherical mirror surface of the optical imaging device of the third embodiment.

[0139] Table 5: Basic parameters of the lens of the optical imaging device of the third embodiment

[0140]

[0141] Table 6: Table of high-order coefficients of the aspherical mirror surface of the optical imaging device of the third embodiment

[0142]

[0143] In the third embodiment, the object side surface and the image side surface of any lens among the first lens E1 to the eighth lens E8 are both aspherical surfaces, and the surface shape x of each aspherical lens can be defined by but not limited to the following aspherical surface formula:

[0144]

[0145] Wherein, x is the distance from the vertex of the aspheric surface to the height h along the optical axis: c is the paraxial curvature of the aspheric surface, c=1R (i.e., the paraxial curvature c is the reciprocal of the radius of curvature R in Table 5 above): k is the cone coefficient: Ai is the correction coefficient of the i-th order of the aspheric surface. Table 6 below gives the high-order coefficients A4, A6, A8, A10, A12, A14, A16, A18, A20, A22, A24, A26, A28 and A30 that can be used for each aspheric mirror surface S1-S14 in the third embodiment.

[0146] Fig. 7A shows the axial chromatic aberration curve of the optical imaging device of the third embodiment, Figure 7B The astigmatism curve of the optical imaging device of the third embodiment is shown. Figure 7C The distortion curve of the optical imaging device of the third embodiment is shown. FIG. 7A to FIG. 7C It can be seen that the optical imaging device provided in the third embodiment has good imaging quality.

[0147] The optical parameters of the optical imaging devices of the first embodiment, the second embodiment and the third embodiment are as follows:

[0148]

[0149] The dimension data tables of the optical imaging devices of the first example, the second example, and the third example of the first embodiment, the first example, the second example, and the third example of the second embodiment, and the first example, the second example, and the third example of the third embodiment are as follows:

[0150] The optical imaging devices of the first embodiment, the second embodiment and the third embodiment satisfy the following relationship:

[0151]

[0152] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0153] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical imaging device, characterized in that: include: A lens barrel assembly, the lens barrel assembly comprising a first lens barrel and a second lens barrel arranged in sequence, wherein the inner annular surface of the first lens barrel and the inner annular surface of the second lens barrel are both stepped; A lens assembly, the lens assembly comprising a first lens with negative focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with positive focal power, a fifth lens with negative focal power, a sixth lens with positive focal power, a seventh lens with negative focal power and an eighth lens with positive focal power, which are sequentially arranged along an optical axis from an object side to an image side; the first lens, the second lens and the third lens are arranged in the first lens barrel, and the fourth lens, the fifth lens, the sixth lens, the seventh lens and the eighth lens are arranged in the second lens barrel; the object side surface of the first lens is a concave surface; the object side surface and the image side surface of the second lens are concave and convex surfaces respectively; the object side surface and the image side surface of the third lens are convex and concave surfaces respectively; the object side surface of the fourth lens is a convex surface; the object side surface and the image side surface of the fifth lens are convex and concave surfaces respectively; the image side surface of the sixth lens is a convex surface; the image side surface of the seventh lens is a concave surface; and the image side surface of the eighth lens is a convex surface; The optical imaging device satisfies the relationship: 0.1<T34 / f4<0.25; 0.60<d02s / R7<1.30; 0<d02s / R6≤0.40; Among them, T34 is the air gap between the third lens and the fourth lens, f4 is the focal length of the fourth lens; d02s is the inner diameter of the object side surface of the second lens barrel, R6 is the curvature radius of the image side surface of the third lens, and R7 is the curvature radius of the object side surface of the fourth lens.

2. The optical imaging device according to claim 1, characterized in that: The image side of the first lens barrel is buckled with the object side of the second lens barrel, and the first lens barrel and the second lens barrel satisfy the relationship: L1+L2>L; Wherein, L1 is the maximum height of the first lens barrel, L2 is the maximum height of the second lens barrel, and L is the maximum height of the entire lens barrel assembly.

3. The optical imaging device according to claim 1, characterized in that: The optical imaging device satisfies the relationship: 0.75<d01m / d02s≤1.9; Wherein, d02s is the inner diameter of the object side surface of the second lens barrel, and d01m is the inner diameter of the image side surface of the first lens barrel.

4. The optical imaging device according to claim 1, characterized in that: The optical imaging device satisfies the relationship: 0.6<(d01s-d01m) / L1<0.75; Wherein, d01s is the inner diameter of the object side surface of the first lens barrel, d01m is the inner diameter of the image side surface of the first lens barrel, and L1 is the maximum height of the first lens barrel.

5. The optical imaging device according to claim 1, characterized in that: The optical imaging device satisfies the relationship: 0<(d01s-d02m) / f<1.1; Among them, d01s is the inner diameter of the object side of the first lens barrel, d02m is the inner diameter of the image side of the second lens barrel, and f is the effective focal length of the optical imaging device.

6. The optical imaging device according to any one of claims 1 to 5, characterized in that: The optical imaging device further includes a first spacing element, the first spacing element is disposed between the first lens and the second lens, and the first spacing element at least partially contacts the image side surface of the first lens; the optical imaging device satisfies the relationship: -0.55<EP011 / f1<-0.4; Wherein, EP011 is the on-axis distance from the object side surface of the first lens barrel to the object side surface of the first spacing element, and f1 is the effective focal length of the first lens.

7. The optical imaging device according to claim 6, characterized in that: The optical imaging device satisfies the relationship: 3.7<(d01s-d1s) / CT1<4.7; Wherein, d01s is the inner diameter of the object side surface of the first lens barrel, d1s is the inner diameter of the object side surface of the first spacing element, and CT1 is the center thickness of the first lens.

8. The optical imaging device according to claim 6, characterized in that: The optical imaging device satisfies the relationship: 0.25<d1s / (f2-f1)≤0.45; Wherein, d1s is the object-side inner diameter of the first spacer element, f1 is the effective focal length of the first lens, and f2 is the effective focal length of the second lens.

9. The optical imaging device according to any one of claims 1 to 5, characterized in that: The optical imaging device further includes a first spacing element and a second spacing element, wherein the first spacing element is disposed between the first lens and the second lens, and the first spacing element at least partially contacts the image side surface of the first lens; the second spacing element is disposed between the second lens and the third lens, and the second spacing element at least partially contacts the image side surface of the second lens; the optical imaging device satisfies the relationship: 0.1<(D1m-D2s) / f2≤0.6; Wherein, D2s is the object side outer diameter of the second spacer element, D1m is the image side outer diameter of the first spacer element, and f2 is the effective focal length of the second lens.

10. The optical imaging device according to claim 9, characterized in that: The optical imaging device satisfies the relationship: -0.80<d1m / R3<-0.40; -1.55<d2s / R4<-0.70; Among them, d1m is the inner diameter of the image side of the first spacing element, d2s is the inner diameter of the object side of the second spacing element, R3 is the curvature radius of the object side of the second lens, and R4 is the curvature radius of the image side of the second lens.

11. The optical imaging device according to claim 9, characterized in that: The optical imaging device satisfies the relationship: 1.3≤(EP011+EP12) / (CT1+CT2)≤1.45; Among them, EP011 is the on-axis distance from the object side surface of the first lens barrel to the object side surface of the first spacing element, EP12 is the on-axis distance from the image side surface of the first spacing element to the object side surface of the second spacing element, CT1 is the center thickness of the first lens, and CT2 is the center thickness of the second lens.

12. The optical imaging device according to claim 9, characterized in that: The optical imaging device satisfies the relationship: 0.35<d2s / f2≤0.65; 0<d2m / f3≤0.45; Among them, d2s is the inner diameter of the second spacer element on the object side, d2m is the inner diameter of the second spacer element on the image side, f2 is the effective focal length of the second lens, and f3 is the effective focal length of the third lens.

Images