Ultrahigh-definition endoscope optical imaging system

Abstract

The invention relates to an ultra-high-definition endoscope optical imaging system which comprises an objective lens system, a relay lens system and an eyepiece system which are sequentially arranged in the light propagation direction. The system is characterized in that the objective lens system comprises a sapphire protection lens, a negative-focal-power lens, a prism or a steering prism, a positive-focal-power plano-convex cemented lens, a negative-focal-power triple cemented lens, a first positive-focal-power triple cemented lens and a first positive-focal-power double cemented lens which are arranged along the light propagation direction; the relay lens group is formed by symmetrically arranging two four-gluing-rod lenses, the convex surface of the first positive-focal-power double-gluing-lens is located on one side of the n groups of relay lenses, and the eyepiece system comprises a second positive-focal-power triple-gluing-lens, a positive-focal-power lens, a second positive-focal-power double-gluing-lens and a sapphire lens which are arranged in the light propagation direction. The central angle resolution is 20C / degree, the distortion is smaller than 15%, the field angle is larger than or equal to 78 degrees, and ultra-high-definition fluorescence imaging of the white light wave band and the near-infrared light wave band can be achieved at the same time.

Description

Technical Field

[0001] The present invention relates to an optical imaging system, in particular to an ultra-high definition endoscope optical imaging system, and belongs to the technical field of optical imaging. Background Art

[0002] With the rapid development of endoscopic optical imaging systems, near-infrared imaging endoscope systems that can be used for both white light imaging and fluorescence bands can determine the location, size, appearance and range of lesions when used for clinical examination and treatment of intra-abdominal diseases, and can carefully observe the tissue structure on the surface of the lesions, and take samples or locate them under direct vision, which greatly improves the accuracy of diagnosis of intra-abdominal diseases and makes up for the shortcomings of traditional diagnosis and treatment methods. Therefore, high-end medical equipment such as ultra-high-definition and fluorescent laparoscopes will have more and more extensive clinical needs in the future, which is an important development direction of laparoscopy.

[0003] However, current fluorescent endoscopes have insufficient imaging quality when performing focused imaging using visible light and near-infrared light, which affects the accuracy of diagnosis or treatment.

[0004] The spatial resolution of an FHD (full high definition) endoscope is about 8C / °, and that of a 4K laparoscope can reach 15C / °. Currently, the mainstream products on the market are still FHD, and only a few products have resolutions slightly higher than FHD. The systems that can simultaneously achieve fluorescence and white light imaging currently have the highest resolution that does not exceed the 15C / ° spatial resolution of a 4K laparoscope.

[0005] Difficulties of existing technology: The clarity of endoscopes with a working band of 0.43-0.86um is mainly determined by the F number of the system. The calculation formula for the limiting resolution of the optical system is With the same band and system parameters, a smaller F number will result in higher spatial resolution.

[0006] The formula for angular resolution of endoscope imaging quality is: Where r(d) is the number of resolvable line pairs per millimeter, and its formula is: At the standard working distance of 50mm, in the same band, the larger the entrance pupil diameter D, the larger the resolution r(d), and the angular resolution r a The higher (d). At present, the mainstream manufacturers’ endoscope products with working band of 0.43-0.86um have a maximum entrance pupil diameter of 0.5mm, which limits the further improvement of angular resolution and resolution.

[0007] However, the wide working band width, small F number and large entrance pupil diameter will introduce greater axial chromatic aberration and vertical chromatic aberration; the difficulty of correcting the accumulated field curvature and vertical chromatic aberration of the relay system is further increased, and the difficulty of compressing the diameter of the optical system is further increased. These parameters will restrict the clarity of the optical system or increase the complexity of the optical system, making it rare in the market to have ultra-high-definition imaging in both white light and fluorescence bands, and all of them have the problems of complex optical system structure, high cost and insufficient imaging clarity, which limits their use, affects detection accuracy and increases the cost of use for hospitals and patients. Summary of the invention

[0008] The purpose of the present invention is to provide an ultra-high-definition endoscopic optical imaging system with a central angular resolution of 20C / °, a distortion of less than 15%, a field of view angle of ≥78°, and the ability to simultaneously achieve ultra-high-definition fluorescence imaging in both white light and near-infrared light bands.

[0009] In order to achieve the above object, the technical solution of the present invention is: an ultra-high-definition endoscope optical imaging system, comprising an objective lens system, a relay lens system and an eyepiece system arranged in sequence along the propagation direction of light, wherein the relay lens system is located between the objective lens system and the eyepiece system.

[0010] The objective lens system is an anti-telephoto structure.

[0011] The relay mirror system includes n relay mirror groups, and each relay mirror group is a double telecentric structure, wherein n is an odd number.

[0012] The eyepiece system is an object-side telecentric structure.

[0013] Its innovation lies in:

[0014] The objective lens system includes a sapphire protective lens, a negative power lens, a prism or a turning prism, a positive power plano-convex glued lens, a negative power triplet, a first positive power triplet and a first positive power doublet, which are arranged along the light propagation direction. The plane on one side of the negative power lens is located on one side of the sapphire protective lens, and the concave surface on the other side thereof is glued to one side of the prism or the turning prism, and the other side of the prism or the turning prism is glued to the plane on one side of the positive power plano-convex glued lens. The negative power triplet is located between the convex surface on the other side of the positive power plano-convex glued lens and the convex surface on one side of the first positive power triplet, and the concave surface on the other side of the first positive power triplet is adjacent to the concave surface of the first positive power doublet.

[0015] The relay lens group is composed of two four-cemented rod lenses arranged symmetrically, and the convex surface of the first positive focal power double-cemented lens is located on one side of the n-group relay lens.

[0016] The eyepiece system includes a second positive power triplet, a positive power lens, a second positive power doublet and a sapphire lens arranged along the direction of light propagation. The second positive power triplet is located between the other side of the n-group relay lens and the concave surface on one side of the positive power lens. The convex surface on the other side of the positive power lens is adjacent to the convex surface on one side of the second positive power doublet, and the plane on the other side of the second positive power doublet is adjacent to the sapphire lens.

[0017] In the above technical solution, the positive focal length plano-convex cemented lens is composed of a first lens and a second lens glued together into one, the other side of the prism or the turning prism is glued to the plane of the first lens, the convex surface of the first lens is glued to the concave surface of the second lens, and the convex surface of the second lens is located on one side of the positive focal length triplet.

[0018] In the above technical solution, the negative focal power triplet is glued together by a first convex lens, a first concave lens and a second convex lens, the concave surfaces on both sides of the first concave lens are respectively glued together with the convex surface on one side of the first convex lens and the convex surface on one side of the second convex lens, the convex surface on the other side of the first convex lens is close to the convex surface on the other side of the positive focal power plano-convex triplet, and the convex surface on the other side of the second convex lens is close to the convex surface on one side of the first positive focal power triplet.

[0019] In the above technical solution, the first positive power triplet is formed by gluing a third convex lens, a second concave lens and a third lens together, the negative power triplet is close to the convex surface on one side of the third convex lens, the convex surface on the other side of the third convex lens is glued to the concave surface on one side of the second concave lens, the concave surface on the other side of the second concave lens is glued to the convex surface of the third lens, and the concave surface of the third lens is adjacent to the concave surface of the first positive power doublet.

[0020] In the above technical solution, the first positive power doublet is formed by gluing a fourth lens and a fifth lens together, the concave surface on one side of the first positive power triplet is adjacent to the concave surface on one side of the fourth lens, the convex surface on the other side of the fourth lens is glued to the concave surface on one side of the fifth lens, and the convex surface on the other side of the fifth lens is located on one side of the n-group relay lens.

[0021] In the above technical scheme, the four-glued rod mirror of each relay lens group is composed of a first biconvex lens, a meniscus rod mirror, a biconcave lens and a second biconvex lens. The two sides of the meniscus rod mirror are respectively glued to the first biconvex lens and the biconcave lens. The convex surface of the first positive focal length double-glued mirror is located on one side of the first biconvex lens, and the outer side of the biconcave lens is glued to the second biconvex lens as a whole. The focal lengths of the first biconvex lens, the meniscus rod mirror, the biconcave lens and the second biconvex lens are not equal, and are all between 25mm and 400mm.

[0022] In the above technical solution, the second positive power triplet lens is composed of a sixth lens, a seventh lens and an eighth lens, the concave surface of the sixth lens is located on the other side of the n-group relay lens, and the convex surface of the sixth lens is glued to the concave surface on one side of the seventh lens, the concave surface on the other side of the seventh lens is glued to the convex surface on one side of the eighth lens, and the convex surface on the other side of the eighth lens is close to the concave surface on one side of the positive power lens.

[0023] In the above technical solution, the second positive power double-glued lens is composed of a third biconvex lens and a ninth lens, the convex surface on the other side of the positive power lens is adjacent to one side of the third biconvex lens, the other side of the third biconvex lens is glued to the concave surface of the ninth lens, and the plane on the other side of the ninth lens is adjacent to the sapphire lens.

[0024] In the above technical solution, the negative optical power lens is a negative lens with an optical power of -0.55 to -0.4, and its focal length is f1 / f 物镜 The ratio satisfies -1.9≤f1 / f 物镜 ≤-0.4, where f1 is the focal length of the negative power lens, f 物镜 is the focal length of the objective lens system,

[0025] The focal length f2 of the positive focal power plano-convex composite lens satisfies 1.8≤f2 / f 物镜 ≤7.5,

[0026] The focal length f3 of the negative power triplet lens satisfies -97≤f3 / f 物镜 ≤-20,

[0027] The focal length f4 of the first positive power triplet lens satisfies 7.5≤f4 / f 物镜 ≤30,

[0028] The focal length f5 of the first positive power doublet lens satisfies 4≤f5 / f 物镜 ≤17.

[0029] In the above technical solution, the focal lengths of the second positive power triplet, the positive power lens and the second positive power doublet are not equal, and are all between 30 mm and 140 mm.

[0030] The positive effect of the present invention is as follows: after adopting the ultra-high-definition endoscope optical imaging system of the present invention, since the objective lens system of the present invention includes a sapphire protective lens, a negative power lens, a prism or a turning prism, a positive power plano-convex glued lens, a negative power triplet, a first positive power triplet and a first positive power doublet arranged along the light propagation direction, the plane on one side of the negative power lens is located on one side of the sapphire protective lens, and the concave surface on the other side thereof is glued to one side of the prism or the turning prism, the other side of the prism or the turning prism is glued to the plane on one side of the positive power plano-convex glued lens, the negative power triplet is located between the convex surface on the other side of the positive power plano-convex glued lens and the convex surface on one side of the first positive power triplet, the concave surface on the other side of the first positive power triplet is adjacent to the concave surface of the first positive power doublet,

[0031] The relay lens group is composed of two four-cemented rod lenses arranged symmetrically, and the convex surface of the first positive focal power double-cemented lens is located on one side of the n-group relay lens.

[0032] The eyepiece system comprises a second positive power triplet, a positive power lens, a second positive power doublet and a sapphire lens arranged along the light propagation direction, wherein the second positive power triplet is located between the other side of the n-group relay lens and the concave surface on one side of the positive power lens, the convex surface on the other side of the positive power lens is adjacent to the convex surface on one side of the second positive power doublet, and the plane on the other side of the second positive power doublet is adjacent to the sapphire lens.

[0033] The working principle of the present invention is that the object is imaged through the objective lens system, and then the image plane is transmitted to the eyepiece system end through the relay lens system and aligned with the pupil of the eyepiece system, and the image is observed by the human eye.

[0034] The objective lens system is used to correct and balance the accumulation of vertical axis aberration and field curvature accumulated by the relay system; the axial chromatic aberration and vertical axis chromatic aberration, field curvature and distortion caused by the large relative aperture from the entire white light band to the fluorescence band are corrected by glass cemented lenses with various dispersion coefficients.

[0035] The relay lens system adopts a symmetrical structure, and balances vertical aberration and telecentricity by adjusting the refractive index, dispersion coefficient and focal length combination of the rod lens. The four-gluing method of a single symmetrical unit not only effectively reduces the vertical axis chromatic aberration and field curvature caused by the large relative aperture, reduces the design difficulty of the objective lens, but also effectively compresses the diameter of the entire relay system.

[0036] The eyepiece system ensures that the F number of the entire optical system is matched without affecting the image quality, and can achieve pupil matching of the adapter.

[0037] Therefore, the optical imaging system of the present invention is a large field of view system, wherein a negative optical focal length lens is used in the objective lens system to effectively compress the field of view light beam, so that the diameter size and distortion of the objective lens are well controlled. In addition, the four-cemented lens in the relay system controls the large aperture chromatic aberration, field curvature, and diameter, so that the entire optical system can well control the diameter size under the condition of large relative aperture so that the overall diameter size meets the requirements.

[0038] The optical imaging system of the present invention realizes an entrance pupil diameter of 0.82mm, an exit pupil diameter of 5mm, a central angle resolution of 20C / °, a distortion of less than 15%, a field of view angle of ≥78°, and a diameter of no more than 6.8mm within a wavelength range of 0.43-0.86um; and can simultaneously realize ultra-high-definition imaging in the white light band and the near-infrared light band. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a structural schematic diagram of a specific implementation mode of the present invention;

[0040] Figure 2 It is a schematic diagram of the structure of the objective lens system of the present invention;

[0041] Figure 3 is a schematic structural diagram of the relay mirror system of the present invention;

[0042] Figure 4 It is a structural schematic diagram of the relay mirror assembly of the present invention;

[0043] Figure 5 is a schematic structural diagram of the eyepiece system of the present invention;

[0044] Figure 6 is a MTF curve diagram of the optical imaging system of the present invention;

[0045] Figure 7 is a distortion diagram of the optical imaging system of the present invention;

[0046] Figure 8 It is an illumination diagram of the optical imaging system of the present invention. DETAILED DESCRIPTION

[0047] The present invention is further described below with reference to the accompanying drawings and given embodiments, but is not limited thereto.

[0048] like Figure 1 , 2 , 3, 4, 5, 6, 7, and 8, an ultra-high-definition endoscope optical imaging system comprises an objective lens system 1, a relay lens system 2, and an eyepiece lens system 3 arranged in sequence along the light propagation direction, wherein the relay lens system 2 is located between the objective lens system 1 and the eyepiece lens system 3.

[0049] The objective lens system 1 is an anti-telephoto structure.

[0050] The relay mirror system 2 includes n relay mirror groups, and each relay mirror group is a double telecentric structure, wherein n is an odd number.

[0051] The eyepiece system 3 is an object-side telecentric structure.

[0052] The objective lens system 1 includes a sapphire protective lens 11, a negative power lens 12, a prism or a turning prism 13, a positive power plano-convex glued lens 14, a negative power triple glued lens 15, a first positive power triple glued lens 16 and a first positive power double glued lens 17, the plane on one side of the negative power lens 12 is located on one side of the sapphire protective lens 11, and the concave surface on the other side is glued to one side of the prism or the turning prism 13, the other side of the prism or the turning prism 13 is glued to the plane on one side of the positive power plano-convex glued lens 14, the negative power triple glued lens 15 is located between the convex surface on the other side of the positive power plano-convex glued lens 14 and the convex surface on one side of the first positive power triple glued lens 16, the concave surface on the other side of the first positive power triple glued lens 16 is adjacent to the concave surface of the first positive power double glued lens 17,

[0053] The relay lens group is composed of two four-cemented rod lenses arranged symmetrically, and the convex surface of the first positive focal power doublet lens 17 is located on one side of the n-group relay lens.

[0054] The eyepiece system 3 includes a second positive power triplet lens 31, a positive power lens 32, a second positive power doublet lens 33 and a sapphire lens 34 arranged along the direction of light propagation. The second positive power triplet lens 31 is located between the other side of the n-group relay lens and the concave surface on one side of the positive power lens 32. The convex surface on the other side of the positive power lens 32 is adjacent to the convex surface on one side of the second positive power doublet lens 33, and the plane on the other side of the second positive power doublet lens 33 is adjacent to the sapphire lens 34.

[0055] like Figure 2 As shown, in order to further improve the rationality of the structure, the positive optical focal length plano-convex glued lens 14 is composed of a first lens 141 and a second lens 142 glued together as one, the other side of the prism or turning prism 13 is glued to the plane of the first lens 141, the convex surface of the first lens 141 is glued to the concave surface of the second lens 142, and the convex surface of the second lens 142 is located on one side of the positive optical focal length triplet 15.

[0056] like Figure 2As shown, the negative power triplet 15 is glued together by a first convex lens 151, a first concave lens 152 and a second convex lens 153, the concave surfaces on both sides of the first concave lens 152 are glued together with the convex surface on one side of the first convex lens 151 and the convex surface on one side of the second convex lens 153, respectively, the convex surface on the other side of the first convex lens 151 is close to the convex surface on the other side of the positive power plano-convex glued lens 14, and the convex surface on the other side of the second convex lens 153 is close to the convex surface on one side of the first positive power triplet 16. The advantages of this design are: first, the chromatic aberration of large relative aperture can be well corrected with the positive power triplet, and second, in the endoscope system, since the adjustment of the lens assembly process cannot be achieved, the three-piece glue method is equivalent to ensuring the mutual processing and position tolerance during component processing, reducing the difficulty of later assembly.

[0057] like Figure 2 As shown, in order to further refine the structure, the first positive power triplet 16 is composed of a third convex lens 161, a second concave lens 162 and a third lens 163 glued together as one body, the negative power triplet 15 is close to the convex surface on one side of the third convex lens 161, the convex surface on the other side of the third convex lens 163 is glued to the concave surface on one side of the second concave lens 162, the concave surface on the other side of the second concave lens 162 is glued to the convex surface of the third lens 163, and the concave surface of the third lens 163 is adjacent to the concave surface of the first positive power doublet 17.

[0058] like Figure 2 As shown, the first positive focal power doublet 17 is formed by gluing the fourth lens 171 and the fifth lens 172 together, the concave surface on one side of the first positive focal power triplet 16 is adjacent to the concave surface on one side of the fourth lens 171, the convex surface on the other side of the fourth lens 171 is glued to the concave surface on one side of the fifth lens 172, and the convex surface on the other side of the fifth lens 172 is located on one side of the n-group relay lens. The advantage of this design is that it can well correct chromatic aberration, field curvature and control telecentricity, reducing the difficulty of later assembly.

[0059] like Figure 3 , 4As shown, the four-glued rod mirror of each relay lens group is composed of a first biconvex lens 21, a meniscus rod mirror 22, a biconcave lens 23 and a second biconvex lens 24. The two sides of the meniscus rod mirror 22 are glued to the first biconvex lens 21 and the biconcave lens 23 respectively. The convex surface of the first positive focal length double-glued lens 17 is located on one side of the first biconvex lens 21. The outer side of the biconcave lens 23 is glued to the second biconvex lens 24 as a whole. The focal lengths of the first biconvex lens 21, the meniscus rod mirror 22, the biconcave lens 23 and the second biconvex lens 24 are not equal, and are all between 25mm and 400mm. The advantage of this design is that it can better correct axial and vertical axis chromatic aberrations, field curvature and telecentricity under large relative apertures; it can not only reduce the difficulty of designing the front-end objective lens system, but also effectively control the diameter of the rod mirror.

[0060] like Figure 5 As shown, the structure is further refined. The second positive power triplet lens 31 is composed of a sixth lens 311, a seventh lens 312 and an eighth lens 313. The concave surface of the sixth lens 311 is located on the other side of the n-group relay lens, and the convex surface of the sixth lens 311 is glued to the concave surface on one side of the seventh lens 312. The concave surface on the other side of the seventh lens 312 is glued to the convex surface on one side of the eighth lens 313. The convex surface on the other side of the eighth lens 313 is close to the concave surface on one side of the positive power lens 32.

[0061] like Figure 5 As shown, further, in order to make the structure more reasonable, the second positive light focal length double-glued lens 33 is composed of a third biconvex lens 331 and a ninth lens 332, the convex surface on the other side of the positive light focal length lens 32 is adjacent to one side of the third biconvex lens 331, the other side of the third biconvex lens 331 is glued to the concave surface of the ninth lens 332, and the plane on the other side of the ninth lens 332 is adjacent to the sapphire lens 34.

[0062] Furthermore, the negative power lens 12 is a negative lens with a power of -0.55 to -0.4, and a focal length of f1 / f 物镜 The ratio satisfies -1.9≤f1 / f 物镜 ≤-0.4, where f1 is the focal length of the negative power lens 12, f 物镜 is the focal length of the objective system 1,

[0063] The focal length f2 of the positive focal power plano-convex cemented lens 14 satisfies 1.8≤f2 / f 物镜 ≤7.5,

[0064] The focal length f3 of the negative power triplet lens 15 satisfies -97≤f3 / f 物镜 ≤-20,

[0065] The focal length f4 of the first positive power triplet lens 16 satisfies 7.5≤f4 / f 物镜 ≤30,

[0066] The focal length f5 of the first positive power doublet lens 17 satisfies 4≤f5 / f 物镜 ≤17.

[0067] The advantages of the design of the present invention are: the negative optical power lens can effectively compress the field light beam, facilitate the folding of the optical path by the steering prism, and compress the diameter of the rear-end system. The vertical axis chromatic aberration field curvature and distortion accumulated by the relay system are effectively reduced by the glued lens combined with the optical power of the rear end and a specific ratio.

[0068] Furthermore, the focal lengths of the second positive power triplet lens 31, the positive power lens 32 and the second positive power doublet lens 33 are not equal, and are all between 30 mm and 140 mm.

[0069] Further, such as Figure 6 As shown in FIG. 1 , the MTF curve of the optical imaging system of the present invention is shown in FIG. 1 when the focal length of the adapter is 15.5 mm. Figure 7 As shown, the distortion of the optical system is less than 15% under the full field of view. Figure 8 As shown, the illumination of the optical system is greater than 0.9 under the full field of view.

[0070] The working principle of the present invention is that the object is imaged through the objective lens system, and then the image plane is transmitted to the eyepiece system end through the relay lens system and aligned with the pupil of the eyepiece system, and the image is observed by the human eye.

[0071] The objective lens system is used to correct and balance the accumulation of vertical axis aberration and field curvature accumulated by the relay system; the axial chromatic aberration and vertical axis chromatic aberration, field curvature and distortion caused by the large relative aperture from the entire white light band to the fluorescence band are corrected by glass cemented lenses with various dispersion coefficients.

[0072] The relay lens system adopts a symmetrical structure, and balances vertical aberration and telecentricity by adjusting the refractive index, dispersion coefficient and focal length combination of the rod lens. The four-gluing method of a single symmetrical unit not only effectively reduces the vertical axis chromatic aberration and field curvature caused by the large relative aperture, reduces the design difficulty of the objective lens, but also effectively compresses the diameter of the entire relay system.

[0073] The eyepiece system ensures that the F number of the entire optical system is matched without affecting the image quality, and can achieve pupil matching of the adapter.

[0074] Therefore, the optical imaging system of the present invention is a large field of view system, wherein a negative optical focal length lens is used in the objective lens system to effectively compress the field of view light beam, so that the diameter size and distortion of the objective lens are well controlled. In addition, the four-cemented lens in the relay system controls the large aperture chromatic aberration, field curvature, and diameter, so that the entire optical system can well control the diameter size under the condition of large relative aperture so that the overall diameter size meets the requirements.

[0075] In summary, the optical imaging system of the present invention is provided with an objective lens system including a sapphire protective lens, a negative power lens, a prism or a turning prism, a positive power plano-convex glued lens, a negative power triplet, a first positive power triplet and a first positive power doublet arranged along the light propagation direction. The lens with negative power can effectively compress the field light beam, facilitate the turning prism to fold the light path, and compress the diameter of the rear-end system; the glued lens with a specific power combination at the rear end can effectively reduce the vertical axis chromatic aberration, field curvature and distortion accumulated by the relay system; and the control of large aperture chromatic aberration, field curvature and diameter by the four glued lenses in the relay system enables the entire optical system to control the diameter size well under the condition of large relative aperture so that the overall diameter size meets the requirements, which not only ensures the mutual processing and position tolerances, but also reduces the difficulty of later assembly. Combined with the eyepiece system that matches the F number of the entire optical system, it can achieve pupil matching of the adapter while achieving an entrance pupil diameter of 0.82mm, an exit pupil diameter of 5mm, a central angle resolution of 20C / °, a distortion of less than 15%, a field of view ≥78°, and a diameter of no more than 6.8mm within the wavelength range of 0.43-0.86um; it can also achieve ultra-high-definition imaging in the white light band and near-infrared light band at the same time.

[0076] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An ultra-high-definition endoscope optical imaging system, comprising an objective lens system (1), a relay lens system (2) and an eyepiece lens system (3) arranged in sequence along a light propagation direction, wherein the relay lens system (2) is located between the objective lens system (1) and the eyepiece lens system (3). The objective lens system (1) is a reverse telephoto structure. The relay mirror system (2) comprises n relay mirror groups, and each relay mirror group is a double telecentric structure, wherein: n is an odd number, The eyepiece system (3) is an object-side telecentric structure. Features: The objective lens system (1) comprises a sapphire protective lens (11) arranged along the light propagation direction, a negative power lens (12), a prism or a turning prism (13), a positive power plano-convex glued lens (14), a negative power triple glued lens (15), a first positive power triple glued lens (16) and a first positive power double glued lens (17), wherein the plane on one side of the negative power lens (12) is located on one side of the sapphire protective lens (11), and the concave surface on the other side thereof is aligned with the sapphire protective lens (11). One side of the prism or the steering prism (13) is glued, the other side of the prism or the steering prism (13) is glued to the plane of one side of the positive focal power plano-convex glued lens (14), the negative focal power triple glued lens (15) is located between the convex surface of the other side of the positive focal power plano-convex glued lens (14) and the convex surface of one side of the first positive focal power triple glued lens (16), the concave surface of the other side of the first positive focal power triple glued lens (16) is adjacent to the concave surface of the first positive focal power double glued lens (17), The relay lens group is composed of two four-cemented rod lenses arranged symmetrically, the convex surface of the first positive focal power double-cemented lens (17) is located on one side of the n-group relay lens, The eyepiece system (3) comprises a second positive power triplet lens (31), a positive power lens (32), a second positive power doublet lens (33) and a sapphire lens (34) arranged along the light propagation direction; the second positive power triplet lens (31) is located between the other side of the n-group relay lens and the concave surface on one side of the positive power lens (32); the convex surface on the other side of the positive power lens (32) is adjacent to the convex surface on one side of the second positive power doublet lens (33); and the plane on the other side of the second positive power doublet lens (33) is adjacent to the sapphire lens (34).

2. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The positive focal power plano-convex cemented lens (14) is formed by gluing a first lens (141) and a second lens (142) together, the other side of the prism or the turning prism (13) is glued to the plane of the first lens (141), the convex surface of the first lens (141) is glued to the concave surface of the second lens (142), and the convex surface of the second lens (142) is located on one side of the positive focal power triple cemented lens (15).

3. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The negative focal power triplet (15) is formed by gluing a first convex lens (151), a first concave lens (152) and a second convex lens (153) together, the concave surfaces on both sides of the first concave lens (152) are respectively glued together with the convex surface on one side of the first convex lens (151) and the convex surface on one side of the second convex lens (153), the convex surface on the other side of the first convex lens (151) is close to the convex surface on the other side of the positive focal power plano-convex triplet (14), and the convex surface on the other side of the second convex lens (153) is close to the convex surface on one side of the first positive focal power triplet (16).

4. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The first positive power triplet (16) is formed by gluing a third convex lens (161), a second concave lens (162) and a third lens (163) together; the negative power triplet (15) is close to the convex surface on one side of the third convex lens (161); the convex surface on the other side of the third convex lens (163) is glued to the concave surface on one side of the second concave lens (162); the concave surface on the other side of the second concave lens (162) is glued to the convex surface of the third lens (163); and the concave surface of the third lens (163) is adjacent to the concave surface of the first positive power doublet (17).

5. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The first positive focal power doublet (17) is formed by gluing a fourth lens (171) and a fifth lens (172) together, the concave surface on one side of the first positive focal power triplet (16) is adjacent to the concave surface on one side of the fourth lens (171), the convex surface on the other side of the fourth lens (171) is glued to the concave surface on one side of the fifth lens (172), and the convex surface on the other side of the fifth lens (172) is located on one side of the n-group relay lens.

6. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The four-glued rod mirror of each relay lens group is composed of a first biconvex lens (21), a meniscus rod mirror (22), a biconcave lens (23) and a second biconvex lens (24); the two sides of the meniscus rod mirror (22) are glued to the first biconvex lens (21) and the biconcave lens (23) respectively; the convex surface of the first positive focal power biconvex lens (17) is located on one side of the first biconvex lens (21); the outer side of the biconcave lens (23) is glued to the second biconvex lens (24) as a whole; the focal lengths of the first biconvex lens (21), the meniscus rod mirror (22), the biconcave lens (23) and the second biconvex lens (24) are not equal and are all between 25 mm and 400 mm.

7. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The second positive focal power triplet lens (31) is composed of a sixth lens (311), a seventh lens (312) and an eighth lens (313); the concave surface of the sixth lens (311) is located on the other side of the n-group relay lens, and the convex surface of the sixth lens (311) is glued to the concave surface on one side of the seventh lens (312); the concave surface on the other side of the seventh lens (312) is glued to the convex surface on one side of the eighth lens (313); and the convex surface on the other side of the eighth lens (313) is close to the concave surface on one side of the positive focal power lens (32).

8. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The second positive power double-cemented lens (33) is composed of a third double-convex lens (331) and a ninth lens (332); the convex surface on the other side of the positive power lens (32) is adjacent to one side of the third double-convex lens (331); the other side of the third double-convex lens (331) is cemented to the concave surface of the ninth lens (332); and the plane on the other side of the ninth lens (332) is adjacent to the sapphire lens (34).

9. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The negative optical power lens (12) is a negative lens with an optical power of -0.55 to -0.4, and a focal length f1 / f 物镜 The ratio satisfies -1.9≤f1 / f 物镜 ≤-0.4, where f1 is the focal length of the negative power lens (12), f 物镜 is the focal length of the objective system (1), The focal length f2 of the positive focal power plano-convex cemented lens (14) satisfies 1.8≤f2 / f 物镜 ≤7.5, The focal length f3 of the negative focal power triplet lens (15) satisfies -97≤f3 / f 物镜 ≤-20, The focal length f4 of the first positive power triplet lens (16) satisfies 7.5≤f4 / f 物镜 ≤30, the focal length f5 of the first positive focal power doublet lens (17) satisfies 4≤f5 / f 物镜 ≤17.

10. The ultra-high definition endoscope optical imaging system according to claim 1, characterized in that: The focal lengths of the second positive power triplet lens (31), the positive power lens (32) and the second positive power doublet lens (33) are not equal and are all between 30 mm and 140 mm.

Images