Endoscope optical assembly
By designing the front fixation component, focusing component, and rear fixation component of the endoscope optical assembly, and using optical compensation to adjust the position of the focusing component, the problem of image quality degradation at different working distances of the endoscope was solved, and high-quality imaging was achieved.
Patent Information
- Application Number
- CN202423217690.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-25
- Publication Date
- 2025-11-04
- Estimated Expiration
- 2034-12-25
AI Technical Summary
Existing endoscopic optical components cannot simultaneously ensure imaging quality at both the proximal and distal ends when the working distance is short, thus limiting their application in medical diagnostics.
Design an endoscope optical assembly including a front fixation assembly, a focusing assembly, and a rear fixation assembly. Adjust the position of the focusing assembly through optical compensation to ensure imaging quality at different working distances.
It achieves unaffected imaging quality within the 0.45um-0.86um band, with an F-number of not less than 5, a field of view of ≥80°, and a working distance of 3-300mm, thus solving the problem of declining imaging quality and expanding its application range.
Smart Images
Figure CN223513390U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to an optical assembly, in particular to an endoscope optical assembly, belongs to optical imaging technical field. BACKGROUND
[0002] Medical endoscope is used for clinical examination of intra-abdominal diseases and treatment, can carefully observe the tissue structure on the lesion surface, and under direct vision, takes material or positioning, greatly improves the accuracy of intra-abdominal disease diagnosis.
[0003] In minimally invasive surgery, for the lens of fixed focal length and relative aperture, shorter working distance can obtain greater magnification, and the details of the lesion tissue are presented more specifically, and the advantages of high resolution of endoscope can be fully played; The working distance of the macro magnifying glass and the fixed focal length electronic endoscope on the market cannot consider the imaging quality of the near end and the far end. The conventional fixed focus scheme in the market, generally, the working distance is short between 30-120mm, the depth of field of the macro lens is between 10-50mm, the imaging quality of the near end and the far end cannot be considered, so that the use range is limited in the medical diagnosis process, therefore, if there is a better performance endoscope imaging system, it will be more helpful to the implementation of, for example, diagnosis and treatment, minimally invasive surgery, etc. SUMMARY
[0004] The utility model aims at providing an endoscope optical assembly which can realize working wave band 0.45um-0.86um range, F number is not less than 5, field of view angle is greater than or equal to 80 DEG, and the imaging quality of working distance 3-300mm is not affected.
[0005] In order to achieve the above object, the technical scheme of the utility model is: an endoscope optical assembly, the innovation point of which is that the optical assembly comprises a front fixed group component, a focusing component and a rear fixed group component arranged in sequence along the light propagation direction,
[0006] The front fixed group component comprises a protection lens, a negative focal length lens, a prism or a turning prism and a positive focal length flat convex lens arranged in sequence along the light propagation direction, the protection lens is arranged on the plane outer side of the negative focal length lens, the concave surface of the negative focal length lens is integrally glued with the plane of the prism or the turning prism and the positive focal length flat convex lens in sequence,
[0007] The focusing component comprises a group of positive focal length double-glued lenses, and the positive focal length flat convex lens is arranged on the plane outer side of the positive focal length double-glued lenses,
[0008] The rear fixed group component comprises a group of double-glued lenses, the convex surface of the positive focal length double-glued lenses is arranged on one side of the convex surface of the double-glued lenses, and the other side of the double-glued lenses is adjacent to the image surface.
[0009] In the technical scheme, the positive-power double-cemented lens is formed by cementing a positive-power plano-convex lens and a positive-power meniscus lens, the positive-power plano-convex lens is located outside the plane of the positive-power plano-convex lens, the convex surface of the positive-power plano-convex lens is cemented with the concave surface of the positive-power meniscus lens, and the convex surface of the positive-power meniscus lens is located on the convex surface side of the double-cemented lens.
[0010] In the technical scheme, the positive-power plano-convex lens and the positive-power meniscus lens are cemented by ultraviolet glue or epoxy resin glue.
[0011] In the technical scheme, the double-cemented lens is formed by cementing a positive-power biconvex lens and a negative-power biconcave lens, the convex surface of the positive-power double-cemented lens is adjacent to the convex surface on one side of the positive-power biconvex lens, the convex surface on the other side of the positive-power biconvex lens is cemented with the concave surface on one side of the negative-power biconcave lens, and the concave surface on the other side of the negative-power biconcave lens is adjacent to the image plane.
[0012] In the technical scheme, the positive-power biconvex lens and the negative-power biconcave lens are cemented by ultraviolet glue or epoxy resin glue.
[0013] In the technical scheme, the negative-power lens is a negative lens with a power of-0.55 to-0.5, and the ratio of the focal length f1 of the negative-power lens to the focal length f of the optical assembly satisfies-1.2≤f1 / f 物镜 ≤-0.3. 物镜 物镜
[0014] The focal length f2 of the positive-power plano-convex lens satisfies 1.5≤f2 / f 物镜 ≤2.5.
[0015] The focal length f3 of the focusing assembly satisfies 2.5≤f3 / f 物镜 ≤3.5.
[0016] The focal length f4 of the rear fixed group assembly satisfies-25≤f4 / f 物镜 ≤-15.
[0017] In the technical scheme, the front fixed group assembly and the rear fixed group assembly are relatively fixed with the image plane, and the distance between the focusing assembly and the image plane satisfies 0.45≤CT1 / TL≤0.7, where CT1 is the thickness of the focusing assembly along the optical axis, and TL is the distance from the image side surface of the front fixed group assembly to the object plane of the rear fixed group assembly.
[0018] In the technical scheme, the protective lens is a quartz glass or a sapphire lens.
[0019] The utility model discloses a positive effect that has is: after adopting the endoscope optical assembly of the utility model, because the utility model optical assembly includes the front fixed group component, focusing component and rear fixed group component that are sequentially arranged along the light propagation direction,
[0020] The front fixed group component includes protection lens, negative power lens, prism or turning prism and positive power flat convex lens which are sequentially arranged along the light propagation direction, the protection lens is arranged on the plane outer side of the negative power lens, the concave surface of the negative power lens is integrally glued with the plane of the prism or turning prism and the positive power flat convex lens,
[0021] The focusing component includes a group of positive power double glued lenses, and the positive power flat convex lens is located on the plane outer side of the positive power double glued lenses,
[0022] The rear fixed group component includes a group of double glued lenses, the convex surface of the positive power double glued lenses is located on the convex surface side of the double glued lenses, and the other side of the double glued lenses is adjacent to the image plane,
[0023] The utility model discloses the position of focusing component is regulated and controlled through the mode of optical compensation, effectively solve the problem of the imaging quality decline of near end and far end of working distance, thereby guaranteeing the imaging quality at different working distances.The utility model system can realize the working waveband 0.45um-0.86um range, and F number is not less than 5, and field of view angle is greater than or equal to 80 DEG, and the working distance can realize 3-300mm imaging quality is not influenced, effectively solve the problem that the working distance use range is limited in the medical diagnosis process. BRIEF DESCRIPTION OF DRAWINGS
[0024] Figure 1 It is the structure schematic diagram of a specific embodiment of the utility model;
[0025] Figure 2 It is the MTF curve diagram of the utility model at working distance 3mm;
[0026] Figure 3 It is the MTF curve diagram of the utility model at working distance 50mm;
[0027] Figure 4 It is the MTF curve diagram of the utility model at working distance 300mm;
[0028] Figure 5 It is the illumination diagram of the optical assembly of the utility model. DETAILED DESCRIPTION
[0029] The utility model is further explained below in conjunction with the drawings and the embodiment given, but is not limited to this.
[0030] As Figure 1、 2 3、4、5, an endoscope optical assembly, the optical assembly comprising a front fixed group assembly 1, a focusing group assembly 2 and a rear fixed group assembly 3 arranged in sequence along the direction of light propagation,
[0031] The front fixed group assembly 1 comprises a protection lens 11, a negative power lens 12, a prism or a turning prism 13 and a positive power plano-convex lens 14 arranged in sequence along the direction of light propagation, the protection lens 11 is arranged outside the plane of the negative power lens 12, the concave surface of the negative power lens 12 is integrally glued with the plane of the prism or the turning prism 13 and the positive power plano-convex lens 14,
[0032] The focusing group assembly 2 comprises a set of positive power double-glued lenses, the positive power plano-convex lens 14 is arranged outside the plane of the positive power double-glued lenses,
[0033] The rear fixed group assembly 3 comprises a set of double-glued lenses, the convex surface of the positive power double-glued lenses is arranged on one side of the convex surface of the double-glued lenses, and the other side of the double-glued lenses is adjacent to the image plane.
[0034] Further, as shown in Figure 1 The positive power double-glued lenses are integrally glued by a positive power plano-convex lens 21 and a positive power meniscus lens 22, the positive power plano-convex lens 14 is arranged outside the plane of the positive power plano-convex lens 21, the convex surface of the positive power plano-convex lens 21 is integrally glued with the concave surface of the positive power meniscus lens 22, and the convex surface of the positive power meniscus lens 22 is arranged on one side of the convex surface of the double-glued lenses. The advantage of this design is that it ensures the machining and positional tolerance of each other, reduces the difficulty of later assembly.
[0035] Further, in order to ensure that the positive power double-glued lenses can be quickly assembled and make the structure more reasonable, the positive power plano-convex lens 21 and the positive power meniscus lens 22 are integrally glued by ultraviolet glue or epoxy resin glue.
[0036] Further, as shown in Figure 1 The double-glued lenses are integrally glued by a positive power lenticular lens 31 and a negative power biconcave lens 32, the convex surface of the positive power double-glued lenses is adjacent to the convex surface on one side of the positive power lenticular lens 31, the convex surface on the other side of the positive power lenticular lens 31 is integrally glued with the concave surface on one side of the negative power biconcave lens 32, and the concave surface on the other side of the negative power biconcave lens 32 is adjacent to the image plane. The advantage of this design is that it not only effectively compensates for the aberration after the movement of the lens group at different working distances, reduces the number of lenses, ensures the machining and positional tolerance of each other, and reduces the difficulty of later assembly.
[0037] Further, in order to ensure that the double-cemented lens can be quickly assembled and make the structure more reasonable, the positive-power lenticular lens 31 and the negative-power lenticular lens 32 are cemented together by UV glue or epoxy resin glue.
[0038] Further, in order to effectively compress the large field of view beam angle and effectively compress the diameter of the system, the negative-power lens 12 is a negative lens with a power of-0.55 to-0.5, and the ratio of the focal length f1 / f 物镜 of the negative-power lens 12 to the focal length f 物镜 of the optical assembly satisfies-1.2≤f1 / f 物镜 ≤-0.3.
[0039] The focal length f2 of the positive-power flat lenticular lens 14 satisfies 1.5≤f2 / f 物镜 ≤2.5.
[0040] The focal length f3 of the focusing assembly 2 satisfies 2.5≤f3 / f 物镜 ≤3.5.
[0041] The focal length f4 of the rear fixed group assembly 3 satisfies-25≤f4 / f 物镜 ≤-15.
[0042] Further, the front fixed group assembly 1 and the rear fixed group assembly 3 are relatively fixed with the image plane position, and the distance between the focusing assembly 2 and the image plane position satisfies 0.45≤CT1 / TL≤0.7, wherein CT1 is the thickness of the focusing assembly 2 along the optical axis, and TL is the distance from the image side surface of the front fixed group assembly 1 to the object plane of the rear fixed group assembly 3. The advantage of such a design is that the moving range is fixed and the distance is small, which can effectively reduce the weight and the range of the moving assembly.
[0043] Further, in order to protect the subsequent lens, the protective lens 11 is a quartz glass or a sapphire lens.
[0044] The detailed structure parameters of the optical assembly of the utility model are as follows:
[0045] No. Radius of curvature r Surface interval d Refractive index n Abbe number vd Object plane infinity 50 1 infinity 0.6 1.77 72.2 2 infinity 0.6 3 infinity 0.3 1.62 53.9 4 1.25 0.213 5 infinity 1.1 1.52 64.2 6 infinity 0.8 1.79 47.4 Stop infinity 2 1.79 47.4 8 infinity 1.7 1.79 47.4 9 -3.362 0.3 10 infinity 1.3 1.47 81.6 11 -1.69 0.5 1.52 63.4 12 -2.85 0.55 13 14.2 1 1.57 71.3 14 -4.3 0.5 1.85 23.8 15 937.1 3.7 16 infinity 0.4 1.52 64.2 17 infinity 0.05
[0046] In the above table, the aspheric surface parameters of serial number 4 are as follows:
[0047]
[0048] In the above embodiment, the corresponding focusing assembly position information under different object distances is as follows:
[0049] Parameter First observation state Second observation state Third observation state Fourth observation state Object distance (mm) 5 50 100 300 Surface 9 (mm) 0.26 0.713 0.748 0.771 Surface 12 (mm) 0.7 0.25 0.2 0.18
[0050] Figure 2This is the MTF transfer function curve for the first observation state in the embodiment. Figure 3 This is the MTF transfer function curve for the third observation state in the embodiment. Figure 4 The MTF transfer function curve for the fourth observation state in the embodiment is shown below. Figure 2 , Figure 3 , Figure 4 It can be seen that the imaging quality is not affected by the working distance of the optical components from 3 to 300 mm, and there is no obvious decline in imaging quality.
[0051] from Figure 5 As can be seen from the illuminance diagram of the optical components, the illuminance of the optical components is not affected by the distance of the optical compensation group, and the illuminance within the field of view is not less than 0.9.
[0052] This invention uses optical compensation to adjust the position of the focusing component, effectively solving the problem of image quality degradation at near and far working distances, thus ensuring image quality at different working distances. This system can achieve an image quality that is unaffected within a working wavelength range of 0.45µm-0.86µm, with an F-number of not less than 5 and a field of view ≥80°, and can operate at distances of 3-300mm, effectively solving the problem of limited working distance range in medical diagnostics.
[0053] 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 endoscope optical assembly, characterized by: The optical assembly comprises a front fixed group assembly (1), a focusing assembly (2) and a rear fixed group assembly (3) arranged in sequence along the light propagation direction, The front fixed group assembly (1) comprises a protective lens (11), a negative power lens (12), a prism or a turning prism (13) and a positive power plano-convex lens (14) arranged in sequence along the light propagation direction, the protective lens (11) is arranged on the plane outer side of the negative power lens (12), the concave surface of the negative power lens (12) is integrally glued with the plane of the prism or the turning prism (13) and the positive power plano-convex lens (14) in sequence, The focusing assembly (2) comprises a group of positive power double-glued lenses, and the positive power plano-convex lens (14) is arranged on the plane outer side of the positive power double-glued lenses, The rear fixed group assembly (3) comprises a group of double-glued lenses, the convex surface of the positive power double-glued lenses is arranged on the convex surface side of the double-glued lenses, and the other side of the double-glued lenses is adjacent to the image plane.
2. The endoscope optical assembly of claim 1, wherein: The positive power double-glued lenses are integrally glued by a positive power plano-convex lens (21) and a positive power meniscus lens (22), the positive power plano-convex lens (14) is arranged on the plane outer side of the positive power plano-convex lens (21), the convex surface of the positive power plano-convex lens (21) is integrally glued with the concave surface of the positive power meniscus lens (22), and the convex surface of the positive power meniscus lens (22) is arranged on the convex surface side of the double-glued lenses.
3. The endoscope optical assembly of claim 2, wherein: The positive power plano-convex lens (21) and the positive power meniscus lens (22) are integrally glued by ultraviolet glue or epoxy resin glue.
4. The endoscope optical assembly of claim 1, wherein: The double-glued lenses are integrally glued by a positive power lenticular lens (31) and a negative power double-concave lens (32), the convex surface of the positive power double-glued lenses is adjacent to the convex surface on one side of the positive power lenticular lens (31), the convex surface on the other side of the positive power lenticular lens (31) is integrally glued with the concave surface on one side of the negative power double-concave lens (32), and the concave surface on the other side of the negative power double-concave lens (32) is adjacent to the image plane.
5. The endoscope optical assembly of claim 4, wherein: The positive power lenticular lens (31) and the negative power double-concave lens (32) are integrally glued by ultraviolet glue or epoxy resin glue.
6. The endoscope optical assembly of claim 1, wherein: The negative power lens (12) is a negative lens with a power of -0.55 to -0.5, the ratio of the focal length f1 / f 物镜 of the optical assembly satisfies -1.2 ≤ f1 / f 物镜 ≤ -0.3, wherein f1 is the focal length of the negative power lens (12), and f 物镜 is the focal length of the optical assembly. The focal length f2 of the positive piano convex lens (14) satisfies 1.5 ≤ f2 / f 物镜 ≤ 2.5, The focal length f3 of the focusing assembly (2) satisfies 2.5≤f3 / f 物镜 ≤3.
5. The focal length f4 of the rear fixed group assembly (3) satisfies -25≤f4 / f 物镜 ≤-15.
7. The endoscope optical assembly of claim 1, wherein: The front fixed group assembly (1) and the rear fixed group assembly (3) are relatively fixed with the image plane position, and the distance between the focusing assembly (2) and the image plane position satisfies 0.45≤CT1 / TL≤0.7, wherein CT1 is the thickness of the focusing assembly (2) along the optical axis, and TL is the distance from the image side surface of the front fixed group assembly (1) to the object plane of the rear fixed group assembly (3).
8. The endoscope optical assembly of claim 1, wherein: The protective lens (11) is a quartz glass or a sapphire lens.