Ultrahigh-definition endoscope optical imaging system
An endoscopic optical imaging system with a specific combination of lenses and prisms has solved the problem of insufficient imaging quality of fluorescence endoscopes, achieving ultra-high-definition imaging, system simplification, and cost reduction.
Patent Information
- Application Number
- CN202422850029.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-21
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2034-11-21
AI Technical Summary
Existing fluorescence endoscopes have insufficient imaging quality in visible and near-infrared light, which limits the accuracy of diagnosis and treatment. Furthermore, their optical systems are complex and costly, making it difficult to achieve ultra-high-definition imaging.
An ultra-high-definition endoscopic optical imaging system is adopted, including an objective lens system, a relay lens system, and an eyepiece system. It utilizes a specific combination of lens and prism structures, corrects chromatic aberration and field curvature through glass cemented lenses with multiple dispersion coefficients, reduces transverse chromatic aberration and field curvature using a symmetrical relay lens system, and compresses the system diameter.
It achieves ultra-high-definition imaging with a center angular resolution of 20 C/°, distortion of less than 15%, and a field of view of ≥78°. It can simultaneously achieve high-quality imaging of white light and near-infrared light in the 0.43-0.86µm band, reducing the complexity and cost of the optical system.
Smart Images
Figure CN223640684U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to an optical imaging system, specifically an ultra-high-definition endoscopic optical imaging system, and belongs to the field of optical imaging technology. Background Technology
[0002] With the rapid development of endoscopic optical imaging systems, near-infrared imaging endoscopes capable of simultaneously using white light and fluorescence bands can determine the location, size, appearance, and extent of lesions during clinical examination and treatment of intra-abdominal diseases. They also allow for detailed observation of the tissue structure on the lesion surface and direct visualization for sampling or localization, significantly improving the accuracy of intra-abdominal disease diagnosis and compensating for the shortcomings of traditional diagnostic methods. Therefore, high-end medical equipment such as ultra-high-definition and fluorescence laparoscopes will see increasingly widespread clinical demand in the future, representing an important direction for the development of laparoscopy.
[0003] However, current fluorescence endoscopes suffer from insufficient image quality when focusing on visible and near-infrared light, affecting the accuracy of diagnosis or treatment.
[0004] The spatial resolution of FHD (Full HD) endoscopes is approximately 8 C / °, while that of 4K laparoscopy can reach 15 C / °. Currently, the mainstream products on the market are still FHD, with only a few products having a slightly higher resolution. Systems that can simultaneously achieve fluorescence and white light imaging have not yet broken through the 15 C / ° spatial resolution of 4K laparoscopy.
[0005] Existing technical challenges: For endoscopes operating in the 0.43-0.86µm wavelength range, the resolution is primarily determined by the system's F-number. The formula for calculating the limiting resolution of the optical system is needed. Under the same band and system parameters, a smaller F-number will have higher spatial resolution.
[0006] The formula for angular resolution of endoscopic imaging quality is: Where r(d) is the limit of resolvable line pairs per millimeter, and its formula is: At the standard working distance of 50mm, under the same wavelength, the larger the entrance pupil diameter D, the larger the resolution r(d), and the larger the angular resolution r. a (d) The higher the value, the better. Currently, mainstream manufacturers' endoscope products with a working wavelength of 0.43-0.86um have a maximum entrance pupil diameter of 0.5mm, which limits further improvements in angular resolution and overall resolution.
[0007] However, a wide operating wavelength, a small F-number, and a large entrance pupil diameter introduce greater axial and transverse chromatic aberration. The difficulty in correcting the field curvature and transverse chromatic aberration accumulated by the relay system further increases, as does the difficulty in compressing the diameter of the optical system. These parameters limit the sharpness of the optical system or increase its complexity, resulting in few rigid laparoscopic products on the market that can simultaneously achieve ultra-high-definition imaging in both white light and fluorescence bands. Furthermore, most of these products suffer from complex optical system structures, high costs, and insufficient imaging sharpness, limiting their use, affecting detection accuracy, and increasing costs for hospitals and patients. Utility Model Content
[0008] The purpose of this invention is to provide an ultra-high-definition endoscopic optical imaging system with a central angular resolution of 20 C / °, distortion of less than 15%, and a field of view of ≥78°, which can simultaneously achieve ultra-high-definition fluorescence imaging in both white light and near-infrared light bands.
[0009] To achieve the above objectives, the technical solution of this utility model is: an ultra-high-definition endoscopic optical imaging system, comprising an objective lens system, a relay lens system, and an eyepiece system arranged sequentially along the direction of light propagation, wherein the relay lens system is located between the objective lens system and the eyepiece system.
[0010] The objective lens system is a reverse telephoto structure.
[0011] The relay mirror system comprises n relay mirror groups, and each relay mirror group is a double telecentric structure, where n is an odd number.
[0012] The eyepiece system has 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 steering prism, a positive power plano-convex cemented lens, a negative power triplet lens, a first positive power triplet lens, and a first positive power doublet lens, all arranged along the direction of light propagation. One side of the negative power lens has a flat surface located on one side of the sapphire protective lens, and its other side has a concave surface cemented to one side of the prism or steering prism. The other side of the prism or steering prism is cemented to a flat surface on one side of the positive power plano-convex cemented lens. The negative power triplet lens is located between the convex surface on the other side of the positive power plano-convex cemented lens and the convex surface on one side of the first positive power triplet lens. The concave surface on the other side of the first positive power triplet lens is adjacent to the concave surface of the first positive power doublet lens.
[0015] The relay lens group consists of two four-cemented rod lenses arranged symmetrically, with the convex surface of the first positive power cemented doublet lens located on one side of the n-group relay lenses.
[0016] The eyepiece system includes a second positive power cemented triplet lens, a positive power lens, a second positive power cemented doublet lens, and a sapphire lens arranged along the direction of light propagation. The second positive power cemented triplet lens is located between the other side of the n sets of relay lenses and the concave surface of one side of the positive power lens. The convex surface of the other side of the positive power lens is adjacent to the convex surface of one side of the second positive power cemented doublet lens, and the flat surface of the other side of the second positive power cemented doublet lens is adjacent to the sapphire lens.
[0017] In the above technical solution, the positive power plano-convex cemented lens is made by cementing a first lens and a second lens together. The other side of the prism or turning prism is cemented to the plane of the first lens. The convex surface of the first lens is cemented to the concave surface of the second lens. The convex surface of the second lens is located on one side of the positive power triple cemented lens.
[0018] In the above technical solution, the negative power cemented lens is made by cementing a first convex lens, a first concave lens, and a second convex lens together. The concave surfaces on both sides of the first concave lens are cemented together with the convex surfaces on one side of the first convex lens and the second convex lens respectively. 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 power plano-convex cemented lens, 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 power cemented lens.
[0019] In the above technical solution, the first positive power cemented triplet lens is composed of a third convex lens, a second concave lens, and a third lens cemented together. The negative power cemented triplet lens has a convex surface near the third convex lens. The convex surface of the third convex lens on the other side is cemented with a concave surface on one side of the second concave lens. The concave surface of the second concave lens on the other side is cemented with a convex surface of the third lens. The concave surface of the third lens is adjacent to the concave surface of the first positive power cemented doublet lens.
[0020] In the above technical solution, the first positive power double cemented lens is made by cementing the fourth lens and the fifth lens together. The concave surface on one side of the first positive power triple cemented lens 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 cemented to the concave surface on one side of the fifth lens. The convex surface on the other side of the fifth lens is located on one side of the n sets of relay lenses.
[0021] In the above technical solution, each relay lens group consists of a first biconvex lens, a meniscus bar lens, a biconcave lens, and a second biconvex lens. The two sides of the meniscus bar lens are cemented to the first biconvex lens and the biconcave lens, respectively. The convex surface of the first positive power cemented doublet lens is located on one side of the first biconvex lens. The outer side of the biconcave lens is cemented to the second biconvex lens. The focal lengths of the first biconvex lens, the meniscus bar lens, 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 triple-cemented 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 cemented with the concave surface on one side of the seventh lens. The concave surface on the other side of the seventh lens is cemented with 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 the positive power lens side.
[0023] In the above technical solution, the second positive power doublet 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 cemented with 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 power lens 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, f 物镜 The focal length of the objective lens system.
[0025] The focal length f2 of the positive optical power plano-convex cemented lens satisfies 1.8 ≤ f2 / f 物镜 ≤7.5,
[0026] The negative optical power cemented lens has a focal length f3 that satisfies -97 ≤ f3 / f 物镜 ≤-20,
[0027] The focal length f4 of the first positive power cemented lens satisfies 7.5 ≤ f4 / f 物镜 ≤30,
[0028] The focal length f5 of the first positive power cemented doublet lens satisfies 4 ≤ f5 / f 物镜 ≤17.
[0029] In the above technical solution, the focal lengths of the second positive power cemented lens, the positive power lens, and the second positive power cemented doublet are not equal, and are all between 30mm and 140mm.
[0030] The positive effects of this invention are as follows: When using the ultra-high-definition endoscopic optical imaging system of this invention, the objective lens system includes a sapphire protective lens, a negative power lens, a prism or steering prism, a positive power plano-convex cemented lens, a negative power triplet lens, a first positive power triplet lens, and a first positive power doublet lens, all arranged along the direction of light propagation. One side of the negative power lens has a flat surface located on one side of the sapphire protective lens, and its other side's concave surface is cemented to one side of the prism or steering prism. The other side of the prism or steering prism is cemented to the flat surface of one side of the positive power plano-convex cemented lens. The negative power triplet lens is located between the convex surface of the other side of the positive power plano-convex cemented lens and the convex surface of one side of the first positive power triplet lens. The concave surface of the other side of the first positive power triplet lens is adjacent to the concave surface of the first positive power doublet lens.
[0031] The relay lens group consists of two four-cemented rod lenses arranged symmetrically, with the convex surface of the first positive power cemented doublet lens located on one side of the n-group relay lenses.
[0032] The eyepiece system includes a second positive power cemented triplet lens, a positive power lens, a second positive power cemented doublet lens, and a sapphire lens, all arranged along the direction of light propagation. The second positive power cemented triplet lens is located between the other side of the n sets of relay lenses and the concave surface of one side of the positive power lens. The convex surface of the other side of the positive power lens is adjacent to the convex surface of one side of the second positive power cemented doublet lens, and the flat surface of the other side of the second positive power cemented doublet lens is adjacent to the sapphire lens.
[0033] The working principle of this invention is as follows: an object is imaged through the objective lens system, and then the image plane is transmitted to the eyepiece system via a relay lens system, where it is aligned with the pupil of the eyepiece system and observed by the human eye.
[0034] The objective lens system is used to correct and balance the accumulation of transverse aberration and field curvature from the relay system; it uses cemented glass lenses with various dispersion coefficients to correct axial and transverse chromatic aberration, field curvature, and distortion caused by the large relative aperture across the entire white light to fluorescence wavelength range.
[0035] The relay lens system, employing a symmetrical structure, balances vertical aberration and telecentrism by adjusting the refractive index, dispersion coefficient, and focal length combination of the bar lenses. The four-cementation method of each symmetrical unit not only effectively reduces transverse chromatic aberration and field curvature caused by the large relative aperture and simplifies objective lens design, but also effectively compresses the diameter of the entire relay system.
[0036] The eyepiece system ensures that matching the F-number of the entire optical system does not affect image quality, and enables pupil matching with the adapter.
[0037] Therefore, the optical imaging system of this utility model is a large field of view system. In the objective lens system, a negative power lens is used to effectively compress the field beam and control the objective lens diameter and distortion. In addition, the four cemented lenses in the relay system control the large aperture chromatic aberration, field curvature and diameter, so that the entire optical system can control the diameter well under the condition of large relative aperture, so that the overall diameter meets the requirements.
[0038] The optical imaging system of this invention achieves an entrance pupil diameter of 0.82 mm, an exit pupil diameter of 5 mm, a central angular resolution of 20 C / °, distortion of less than 15%, a field of view of ≥78°, and a diameter of no more than 6.8 mm within a wavelength range of 0.43-0.86 μm. It can simultaneously achieve ultra-high-definition imaging in both white light and near-infrared light bands. Attached Figure Description
[0039] Figure 1 This is a structural schematic diagram of one specific embodiment of the present invention;
[0040] Figure 2 This is a schematic diagram of the objective lens system structure of this utility model;
[0041] Figure 3 This is a schematic diagram of the relay mirror system of this utility model;
[0042] Figure 4 This is a schematic diagram of the relay lens assembly of this utility model;
[0043] Figure 5 This is a schematic diagram of the eyepiece system of this utility model;
[0044] Figure 6 This is the MTF curve of the optical imaging system of this utility model;
[0045] Figure 7 This is a distortion diagram of the optical imaging system of this utility model;
[0046] Figure 8 This is the illuminance diagram of the optical imaging system of this utility model. Detailed Implementation
[0047] The present invention will be further described below with reference to the accompanying drawings and the given embodiments, but it is not limited thereto.
[0048] like Figure 1 , 2 As shown in Figures 3, 4, 5, 6, 7, and 8, an ultra-high-definition endoscopic optical imaging system includes an objective lens system 1, a relay lens system 2, and an eyepiece system 3 arranged sequentially along the direction of light propagation. The relay lens system 2 is located between the objective lens system 1 and the eyepiece system 3.
[0049] The objective lens system 1 is a reverse telephoto structure.
[0050] The relay mirror system 2 includes n relay mirror groups, and each relay mirror group is a double telecentric structure, where n is an odd number.
[0051] The eyepiece system 3 has 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 steering prism 13, a positive power plano-convex cemented lens 14, a negative power triplet lens 15, a first positive power triplet lens 16, and a first positive power doublet lens 17, all arranged along the direction of light propagation. One side of the negative power lens 12 has a flat surface located on one side of the sapphire protective lens 11, and its other side has a concave surface cemented to one side of the prism or steering prism 13. The other side of the prism or steering prism 13 is cemented to a flat surface on one side of the positive power plano-convex cemented lens 14. The negative power triplet lens 15 is located between the convex surface on the other side of the positive power plano-convex cemented lens 14 and the convex surface on one side of the first positive power triplet lens 16. The concave surface on the other side of the first positive power triplet lens 16 is adjacent to the concave surface of the first positive power doublet lens 17.
[0053] The relay lens group consists of two four-cemented rod lenses arranged symmetrically, with the convex surface of the first positive power cemented doublet lens 17 located on one side of the n-group relay lenses.
[0054] The eyepiece system 3 includes a second positive power cemented triplet lens 31, a positive power lens 32, a second positive power cemented doublet lens 33, and a sapphire lens 34 arranged along the direction of light propagation. The second positive power cemented triplet lens 31 is located between the other side of the n sets of relay lenses and the concave surface of one side of the positive power lens 32. The convex surface of the other side of the positive power lens 32 is adjacent to the convex surface of one side of the second positive power cemented doublet lens 33, and the flat surface of the other side of the second positive power cemented doublet lens 33 is adjacent to the sapphire lens 34.
[0055] like Figure 2 As shown, in order to further improve the structural rationality, the positive power plano-convex cemented mirror 14 is made of a first lens 141 and a second lens 142 cemented together. The other side of the prism or turning prism 13 is cemented to the plane of the first lens 141, the convex surface of the first lens 141 is cemented 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 power triple cemented mirror 15.
[0056] like Figure 2As shown, the negative power cemented triplet lens 15 is composed of a first convex lens 151, a first concave lens 152, and a second convex lens 153 cemented together. The concave surfaces on both sides of the first concave lens 152 are cemented together with the convex surfaces on one side of the first convex lens 151 and 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 cemented 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 cemented triplet lens 16. The advantages of this design are: first, it can effectively correct chromatic aberration with a large relative aperture when paired with a positive power cemented triplet lens; second, in an endoscope system, since lens adjustment during the assembly process is impossible, the three-piece cementation method ensures mutual processing and positional tolerances during component manufacturing, reducing the difficulty of subsequent assembly.
[0057] like Figure 2 As shown, to further refine the structure, the first positive power cemented triplet lens 16 is made of a third convex lens 161, a second concave lens 162 and a third lens 163 cemented together. The negative power cemented triplet lens 15 has a convex surface close to the third convex lens 161 on one side. The convex surface of the third convex lens 161 on the other side is cemented with the concave surface of the second concave lens 162 on one side. The concave surface of the second concave lens 162 on the other side is cemented with the convex surface of the third lens 163. The concave surface of the third lens 163 is adjacent to the concave surface of the first positive power cemented doublet lens 17.
[0058] like Figure 2 As shown, the first positive power cemented doublet lens 17 is formed by cementing a fourth lens 171 and a fifth lens 172 together. The concave surface of one side of the first positive power cemented triplet lens 16 is adjacent to the concave surface of one side of the fourth lens 171, and the convex surface of the other side of the fourth lens 171 is cemented to the concave surface of one side of the fifth lens 172. The convex surface of the other side of the fifth lens 172 is located on one side of the n-group relay lenses. The advantage of this design is that it effectively corrects chromatic aberration, field curvature, and controls telecentrism, while reducing the difficulty of subsequent assembly.
[0059] like Figure 3 , 4As shown, each relay lens group consists of a first biconvex lens 21, a meniscus bar lens 22, a biconcave lens 23, and a second biconvex lens 24. The two sides of the meniscus bar lens 22 are cemented to the first biconvex lens 21 and the biconcave lens 23, respectively. The convex surface of the first positive power cemented doublet 17 is located on one side of the first biconvex lens 21. The outer side of the biconcave lens 23 is cemented to the second biconvex lens 24. The focal lengths of the first biconvex lens 21, the meniscus bar lens 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 transverse chromatic aberration, field curvature, and telecentrism under large relative apertures; it not only reduces the design difficulty of the front-end objective lens system but also effectively controls the diameter of the bar lens.
[0060] like Figure 5 As shown, further refining the structure, the second positive power cemented 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 lenses, and the convex surface of the sixth lens 311 is cemented with the concave surface on one side of the seventh lens 312. The concave surface on the other side of the seventh lens 312 is cemented with 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 the positive power lens 32.
[0061] like Figure 5 As shown, further, in order to make the structure more reasonable, the second positive power doublet 33 is composed of a third biconvex lens 331 and a ninth lens 332. The convex surface of the other side of the positive power lens 32 is adjacent to one side of the third biconvex lens 331, the other side of the third biconvex lens 331 is cemented with the concave surface of the ninth lens 332, and the plane of 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 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 The focal length of objective lens system 1,
[0063] The positive focal length plano-convex cemented lens 14 has a focal length f2 that satisfies 1.8 ≤ f2 / f 物镜 ≤7.5,
[0064] The negative optical power cemented lens 15 has a focal length f3 that satisfies -97 ≤ f3 / f 物镜 ≤-20,
[0065] The first positive power cemented lens 16 has a focal length f4 that satisfies 7.5 ≤ f4 / f 物镜 ≤30,
[0066] The focal length f5 of the first positive power cemented doublet 17 satisfies 4 ≤ f5 / f 物镜 ≤17.
[0067] The advantages of this design are: the negative power lens can effectively compress the field beam, which is beneficial for the folding of the optical path by the steering prism and the reduction of the diameter of the back-end system. The cemented lens, combined with a specific ratio of optical power at the back end, effectively reduces the cumulative transverse chromatic aberration, field curvature, and distortion of the relay system.
[0068] Furthermore, the focal lengths of the second positive power cemented lens 31, the positive power lens 32, and the second positive power cemented doublet 33 are not equal, and are all between 30mm and 140mm.
[0069] Furthermore, such as Figure 6 As shown, the MTF curve of the optical imaging system of this invention at an adapter focal length of 15.5mm is as follows. Figure 7 As shown, the optical system exhibits less than 15% distortion across the entire field of view. Figure 8 As shown, the illuminance of the optical system across the entire field of view is greater than 0.9.
[0070] The working principle of this invention is as follows: an object is imaged through the objective lens system, and then the image plane is transmitted to the eyepiece system via a relay lens system, where it is aligned with the pupil of the eyepiece system and observed by the human eye.
[0071] The objective lens system is used to correct and balance the accumulation of transverse aberration and field curvature from the relay system; it uses cemented glass lenses with various dispersion coefficients to correct axial and transverse chromatic aberration, field curvature, and distortion caused by the large relative aperture across the entire white light to fluorescence wavelength range.
[0072] The relay lens system, employing a symmetrical structure, balances vertical aberration and telecentrism by adjusting the refractive index, dispersion coefficient, and focal length combination of the bar lenses. The four-cementation method of each symmetrical unit not only effectively reduces transverse chromatic aberration and field curvature caused by the large relative aperture and simplifies objective lens design, but also effectively compresses the diameter of the entire relay system.
[0073] The eyepiece system ensures that matching the F-number of the entire optical system does not affect image quality, and enables pupil matching with the adapter.
[0074] Therefore, the optical imaging system of this utility model is a large field of view system. In the objective lens system, a negative power lens is used to effectively compress the field beam and control the objective lens diameter and distortion. In addition, the four cemented lenses in the relay system control the large aperture chromatic aberration, field curvature and diameter, so that the entire optical system can control the diameter well under the condition of large relative aperture, so that the overall diameter meets the requirements.
[0075] In summary, the optical imaging system of this invention comprises an objective lens system consisting of a sapphire protective lens, a negative power lens, a prism or steering prism, a positive power plano-convex cemented lens, a negative power triplet lens, a first positive power triplet lens, and a first positive power doublet lens, arranged along the direction of light propagation. The negative power lens effectively compresses the field beam, facilitating the folding of the optical path by the steering prism and reducing the diameter of the rear-end system. The cemented lens at the rear end, combined with a specific ratio of optical power, effectively reduces the accumulated transverse chromatic aberration, field curvature, and distortion of the relay system. Furthermore, the four cemented lenses in the relay system control the chromatic aberration, field curvature, and diameter of the large aperture, allowing the entire optical system to effectively control the diameter size under large relative aperture conditions, ensuring that the overall diameter meets the requirements. This not only guarantees the mutual processing and positional tolerances but also reduces the difficulty of subsequent assembly. Combined with an eyepiece system that matches the F-number of the entire optical system, it can achieve pupil matching of the adapter while realizing an entrance pupil diameter of 0.82mm, an exit pupil diameter of 5mm, a central angular resolution of 20 C / °, distortion of less than 15%, a field of view of ≥78°, and a diameter of no more than 6.8mm within the wavelength range of 0.43-0.86um; it can simultaneously achieve ultra-high-definition imaging in both white light and near-infrared light bands.
[0076] Based on the above-described preferred embodiments of this utility model, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the technical concept of this utility model. The technical scope of this utility model is not limited to the contents of the specification, but must be determined according to the scope of the claims.
Claims
1. An ultra-high-definition endoscopic optical imaging system, comprising an objective lens system (1), a relay lens system (2), and an eyepiece system (3) arranged sequentially along the direction of light propagation, wherein the relay lens system (2) is located between the objective lens system (1) and the eyepiece system (3). The objective lens system (1) is a reverse telephoto structure. The relay mirror system (2) includes n sets of relay mirrors, and each set of relay mirrors is a double telecentric structure, wherein, When n is odd, The eyepiece system (3) has an object-side telecentric structure. Its features are: The objective lens system (1) includes a sapphire protective lens (11) arranged along the direction of light propagation, a negative power lens (12), a prism or directional prism (13), a positive power plano-convex cemented lens (14), a negative power triplet lens (15), a first positive power triplet lens (16), and a first positive power doublet 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 its other side is parallel to the plane on the sapphire protective lens (11). One side of the prism or turning prism (13) is cemented together, and the other side of the prism or turning prism (13) is cemented together with the plane of one side of the positive power plano-convex cemented lens (14). The negative power triple cemented lens (15) is located between the convex surface of the other side of the positive power plano-convex cemented lens (14) and the convex surface of one side of the first positive power triple cemented lens (16). The concave surface of the other side of the first positive power triple cemented lens (16) is adjacent to the concave surface of the first positive power double cemented lens (17). The relay lens group is composed of two four-cemented rod lenses arranged symmetrically, and the convex surface of the first positive power cemented doublet lens (17) is located on one side of the n-group relay lens. The eyepiece system (3) includes a second positive power cemented triplet lens (31), a positive power lens (32), a second positive power cemented doublet lens (33), and a sapphire lens (34) arranged along the direction of light propagation. The second positive power cemented triplet lens (31) is located between the other side of the n-group relay lens and the concave surface of one side of the positive power lens (32). The convex surface of the other side of the positive power lens (32) is adjacent to the convex surface of one side of the second positive power cemented doublet lens (33), and the flat surface of the other side of the second positive power cemented doublet lens (33) is adjacent to the sapphire lens (34).
2. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The positive power plano-convex cemented mirror (14) is made by cementing a first lens (141) and a second lens (142) together. The other side of the prism or turning prism (13) is cemented to the plane of the first lens (141). The convex surface of the first lens (141) is cemented to the concave surface of the second lens (142). The convex surface of the second lens (142) is located on one side of the positive power triple cemented mirror (15).
3. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The negative power cemented triplet lens (15) is cemented together with 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 cemented together with the convex surfaces on one side of the first convex lens (151) and 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 cemented 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 cemented triplet lens (16).
4. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The first positive power cemented triplet lens (16) is cemented together by a third convex lens (161), a second concave lens (162) and a third lens (163). The negative power cemented triplet lens (15) has a convex surface on the side close to the third convex lens (161). The convex surface on the other side of the third convex lens (161) is cemented with a 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 cemented with a convex surface of the third lens (163). The concave surface of the third lens (163) is adjacent to the concave surface of the first positive power cemented doublet lens (17).
5. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The first positive power double cemented lens (17) is cemented together with the fourth lens (171) and the fifth lens (172). The concave surface on one side of the first positive power triple cemented lens (16) is adjacent to the concave surface on one side of the fourth lens (171), and the convex surface on the other side of the fourth lens (171) is cemented to the concave surface on one side of the fifth lens (172). 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 endoscopic optical imaging system according to claim 1, characterized in that: Each relay lens group consists of a first biconvex lens (21), a meniscus bar lens (22), a biconcave lens (23), and a second biconvex lens (24). The two sides of the meniscus bar lens (22) are cemented to the first biconvex lens (21) and the biconcave lens (23), respectively. The convex surface of the first positive power cemented doublet lens (17) is located on one side of the first biconvex lens (21). The outer side of the biconcave lens (23) is cemented to the second biconvex lens (24). The focal lengths of the first biconvex lens (21), the meniscus bar lens (22), the biconcave lens (23), and the second biconvex lens (24) are not equal and are all between 25mm and 400mm.
7. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The second positive power cemented 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 cemented with the concave surface on one side of the seventh lens (312). The concave surface on the other side of the seventh lens (312) is cemented with 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 the side of the positive power lens (32).
8. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The second positive power doublet (33) is composed of a third biconvex lens (331) and a ninth lens (332). The convex surface of the other side of the positive power lens (32) is adjacent to one side of the third biconvex lens (331), the other side of the third biconvex lens (331) is cemented with the concave surface of the ninth lens (332), and the plane of the other side of the ninth lens (332) is adjacent to the sapphire lens (34).
9. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The negative power lens (12) is a negative lens with an optical 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 The focal length of the objective lens system (1) is... The focal length f2 of the positive optical power plano-convex cemented lens (14) satisfies 1.8 ≤ f2 / f 物镜 ≤7.5, The negative optical power cemented lens (15) has a focal length f3 that satisfies -97 ≤ f3 / f 物镜 ≤-20, The focal length f4 of the first positive power cemented lens (16) satisfies 7.5 ≤ f4 / f 物镜 ≤30, The focal length f5 of the first positive power cemented doublet (17) satisfies 4 ≤ f5 / f 物镜 ≤17.
10. The ultra-high-definition endoscopic optical imaging system according to claim 1, characterized in that: The focal lengths of the second positive power cemented triplet lens (31), the positive power lens (32), and the second positive power cemented doublet lens (33) are not equal, and are all between 30mm and 140mm.