Optical lens group and rod lens system

Abstract

The utility model relates to the technical field of hard endoscopes, and discloses an optical lens group and a rod lens system. The optical lens group comprises a first lens group, a diaphragm and a second lens group which are sequentially arranged along the direction from an object plane to an imaging plane, and the first lens group comprises a first lens, a second lens and a third lens which are sequentially arranged along the direction. And the second lens group comprises a third lens, a second lens and a first lens which are sequentially arranged in the direction. The rod lens system comprises an odd number of optical lens sets which are sequentially arranged in the direction from the object plane to the imaging plane, the optical lens sets and the rod lens system have the advantages of being small in size, convenient to assemble and low in cost, and high-quality imaging can be obtained after the optical lens sets and the rod lens system are applied to an endoscope.

Description

Technical Field

[0001] The utility model relates to the technical field of rigid endoscopes, in particular to an optical lens group and a rod mirror system. Background Art

[0002] Rigid endoscopes, with their clear imaging, low price, and easy operation, play an important role in many medical examinations, diagnoses, and treatments. They are primarily used for the diagnosis and / or treatment of lesions in shallow natural cavities or in oral cavities opened through puncture, and they cannot be bent during operation. During the diagnosis and treatment process, medical staff insert the lens and a slender tube into the cavity. The objective lens on the lens approaches the object being observed, and the medical staff observes the object through the external eyepiece. To enable in-depth observation of the lesion, the tube is designed to have a certain length, such as 30 cm for laparoscopes. A rod mirror system is installed in the tube to act as a relay image transmission system.

[0003] However, the existing rod mirror system or the optical lens group in the rod mirror system is large in size and complex in structure, and is difficult to assemble in a slender mirror tube. Therefore, it is of practical value to develop a rod mirror system that is small in size, simple in structure and easy to assemble. Utility Model Content

[0004] The present invention aims to solve at least one of the technical problems in the prior art. To this end, the present invention provides an optical lens assembly and a rod lens system, which have the advantages of small size, easy assembly and low cost.

[0005] In a first aspect, an optical lens assembly according to an embodiment of the present invention includes:

[0006] A first lens group, an aperture, and a second lens group are arranged in sequence along a direction from the object plane to the imaging plane. The first lens group includes a first lens, a second lens, and a third lens arranged in sequence along the direction. The second lens group includes a third lens, a second lens, and a first lens arranged in sequence along the direction.

[0007] According to some embodiments of the embodiments of the present invention, the first lens, the second lens, and the third lens are all glass spherical lenses.

[0008] According to some embodiments of the present invention, the first lens is a plano-convex lens with positive optical power, the second lens is a concave-convex lens with positive optical power, and the third lens is a concave-convex lens with negative optical power.

[0009] According to some embodiments of the embodiments of the present invention, the first lens abuts against the first surface of the second lens, and the third lens abuts against the second surface of the second lens.

[0010] According to some embodiments of the present invention, a first distance between the first lens group and the aperture is equal to a second distance between the second lens group and the aperture.

[0011] The optical lens assembly of the present invention has at least the following beneficial effects: the second lens group and the first lens group are arranged to be symmetrical about the aperture, so that the optical lens assembly is small in size, the internal lens assembly is simple, and the cost is low.

[0012] In a second aspect, a rod mirror system according to an embodiment of the present invention includes an optical lens assembly as described in any one of the first aspects above.

[0013] According to some embodiments of the present invention, the rod mirror system includes a plurality of optical lens groups sequentially arranged along a direction from the object plane to the imaging plane.

[0014] According to some embodiments of the present invention, the rod mirror system includes an odd number of optical lens groups arranged in sequence along the direction from the object plane to the imaging plane.

[0015] According to some embodiments of the present invention, the distance between every two adjacent optical lens groups is set to be the same.

[0016] The rod mirror system of the present invention has at least the following beneficial effects: the rod mirror system is small in size and can meet the installation requirements of the slender structure insertion part of the endoscope, and is easy to assemble in the endoscope to obtain high-quality imaging.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 This is a schematic structural diagram of an optical lens assembly according to an embodiment of the present invention;

[0020] Figure 2 A schematic diagram of parameters of an optical lens assembly according to an embodiment of the present utility model;

[0021] Figure 3 This is a schematic structural diagram of a rod mirror system according to an embodiment of the present invention;

[0022] Figure 4 This is the MTF diagram of the rod mirror system according to an embodiment of the present invention;

[0023] Figure 5This is a relative illumination diagram of the rod mirror system according to an embodiment of the present invention.

[0024] Reference numerals: first lens 1 , second lens 2 , third lens 3 . DETAILED DESCRIPTION

[0025] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0026] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0027] In the description of this utility model, "several" means one or more, "more" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of terms such as "first" and "second" is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, or implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0028] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably confirm the specific meaning of the above terms in the present invention in combination with the specific content of the technical solution.

[0029] First, reference Figure 1 According to an embodiment of the present invention, an optical lens group includes: a first lens group, an aperture, and a second lens group arranged in sequence along the direction from the object plane to the imaging plane. The first lens group includes a first lens 1, a second lens 2, and a third lens 3 arranged in sequence along the direction from the object plane to the imaging plane. The second lens group includes a third lens 3, a second lens 2, and a first lens 1 arranged in sequence along the direction from the object plane to the imaging plane.

[0030] According to some embodiments of the present invention, the first lens 1 , the second lens 2 , and the third lens 3 are all glass spherical lenses.

[0031] Among them, the lens types used by the first lens 1, the second lens 2, and the third lens 3 include but are not limited to glass spherical lenses, and the lens type can be determined according to actual imaging needs.

[0032] According to some embodiments of the present invention, the first lens 1 is a plano-convex lens with positive optical power, the second lens 2 is a concave-convex lens with positive optical power, and the third lens 3 is a concave-convex lens with negative optical power.

[0033] Among them, the optical focal length range of the first lens 1 is greater than 6 and less than 12, the optical focal length range of the second lens 2 is greater than 5 and less than 10, and the optical focal length range of the third lens 3 is greater than -30 and less than -10. It is conceivable that the optical focal lengths of the first lens 1, the second lens 2, and the third lens 3 can also be other numerical ranges or values, and the numerical ranges or values ​​can be determined according to actual imaging requirements.

[0034] According to some embodiments of the present invention, the diameter of the optical lens assembly is greater than or equal to 2.7 and less than or equal to 3.2 mm. The first lens 1 abuts the first surface of the second lens 2, and the third lens 3 abuts the second surface of the second lens 2. The first lens 1 and the second lens 2, as well as the second lens 2 and the third lens 3, are all glued together, resulting in a smaller optical lens assembly and simplified assembly.

[0035] Among them, reference Figure 1 In the first lens group, the first surface of the second lens 2 refers to the surface of the second lens 2 closest to the object plane; the second surface of the second lens 2 refers to the surface of the second lens 2 closest to the aperture stop. In the second lens group, the first surface of the second lens 2 refers to the surface of the second lens 2 closest to the imaging plane; the second surface of the second lens 2 refers to the surface of the second lens 2 closest to the aperture stop.

[0036] According to some embodiments of the present invention, a first distance between the first lens group and the aperture is equal to a second distance between the second lens group and the aperture.

[0037] Among them, reference Figure 1 The first spacing refers to the distance between the surface of the third lens 3 closest to the aperture and the aperture, and the third lens 3 is in the first lens group. The second spacing refers to the distance between the surface of the third lens 3 closest to the aperture and the aperture, and the third lens 3 is in the second lens group.

[0038] Among them, reference Figure 2, some parameters of each lens in the optical lens group (first lens group and second lens group) can be selected as follows: the curvature radius of the counter-contact surface (surface 2 or surface 8) of the first lens 1 and the second lens 2 is -8.39, the refractive index is 1.94, and the Abbe number is 17.94; the curvature radius of the counter-contact surface (surface 3 or surface 7) of the second lens 2 and the second lens 3 is -4.77, the refractive index is 1.48, and the Abbe number is 70.44; the curvature radius of the surface of the third lens 3 close to the aperture is -8.81, the refractive index is 1.67, and the Abbe number is 32.17; the thickness of the first lens 1 is 2.45mm, the thickness of the second lens 2 is 23.57mm, and the thickness of the third lens 3 is 3.00mm. The first spacing and the second spacing are both set to 0.5mm. The distance between the object plane and the surface close to the object plane in the first lens 1, and the distance between the imaging plane and the imaging plane close to the imaging plane in the first lens 1 are both set to 2.24mm. Reference Figure 2 , surface 0 is the surface where the object plane is located; in the first lens group, surface 1 is the surface of the first lens 1 close to the object plane, surface 2 is the surface of the first lens 1 close to the imaging plane or the surface of the second lens 2 close to the object plane, surface 3 is the surface of the second lens 2 close to the imaging plane or the surface of the third lens 3 close to the object plane, and surface 4 is the surface of the third lens 3 close to the imaging plane; surface 5 is the surface where the aperture is located; in the second lens group, surface 6 is the surface of the third lens 3 close to the object plane, surface 7 is the surface of the third lens 3 close to the imaging plane or the surface of the second lens 2 close to the object plane, surface 8 is the surface of the second lens 2 close to the imaging plane or the surface of the first lens 1 close to the object plane, and surface 9 is the surface of the first lens 1 close to the imaging plane; surface 10 is the surface where the imaging plane is located.

[0039] An optical lens assembly of the present invention has at least the following beneficial effects: by setting the distance between the first lens 1 and the second lens 2, the distance between the second lens 2 and the third lens 3, and the distance between the third lens 3 and the aperture in the first lens assembly to specific values ​​or value ranges, and by setting the second lens assembly and the first lens assembly to be symmetrical about the aperture, the optical lens assembly is made small in size and has simple internal structure assembly.

[0040] In a second aspect, a rod mirror system according to an embodiment of the present invention includes the optical lens assembly as described in the first aspect above.

[0041] According to some embodiments of the present invention, the rod mirror system includes a plurality of optical lens groups sequentially arranged along a direction from the object plane to the imaging plane.

[0042] According to some embodiments of the present invention, the rod mirror system includes an odd number of optical lens groups arranged in sequence along a direction from the object plane to the imaging plane.

[0043] Among them, an odd number of optical lens groups can ensure that the image formed by the rod mirror system is positive.

[0044] refer to Figure 3 According to some embodiments of the present invention, the rod mirror system includes five optical lens groups arranged in sequence along the direction from the object plane to the imaging plane.

[0045] refer to Figure 3 According to some embodiments of the present invention, in the five optical lens groups, the distance between every two adjacent optical lens groups is set to be the same.

[0046] Among the five optical lens groups, the distance between every two adjacent optical lens groups is set to 4.48 mm.

[0047] refer to Figure 4 , Figure 4 This is the MTF curve of the rod mirror system of this application under visible light, Figure 4 It can be seen that when the spatial frequency of the rod mirror system of the present application is 159lp / mm, the full field MTF value is greater than 0.2, and the imaging quality of the rod mirror system is excellent. Figure 5 , Figure 5 This is the relative illumination curve of the rod mirror system of this application under visible light, from Figure 5 It can be seen from the figure that the relative illumination of the rod mirror system of the present application is 100% on the image plane, and the imaging picture of the rod mirror system of the present application has uniform brightness.

[0048] The rod mirror system of the present invention has at least the following beneficial effects: the rod mirror system of the present application is small in size, can meet the installation requirements of the slender structure insertion part of the endoscope, has a simple structure, can be quickly assembled in the endoscope, reduces production and manufacturing costs, and can provide excellent imaging quality and uniform brightness of the imaging picture.

[0049] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative use of the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0050] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and purpose of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An optical lens assembly, characterized in that: include: A first lens group, an aperture, and a second lens group are arranged in sequence along a direction from the object plane to the imaging plane. The first lens group includes a first lens, a second lens, and a third lens arranged in sequence along the direction. The second lens group includes a third lens, a second lens, and a first lens arranged in sequence along the direction.

2. The optical lens assembly according to claim 1, wherein: The first lens, the second lens, and the third lens are all glass spherical lenses.

3. The optical lens assembly according to claim 1, wherein: The first lens is a plano-convex lens with positive optical power, the second lens is a concave-convex lens with positive optical power, and the third lens is a concave-convex lens with negative optical power.

4. The optical lens assembly according to claim 1, wherein: The first lens abuts against a first surface of the second lens, and the third lens abuts against a second surface of the second lens.

5. The optical lens assembly according to claim 1, wherein: A first distance between the first lens group and the aperture is equal to a second distance between the second lens group and the aperture.

6. A rod mirror system, characterized in that: The optical lens assembly comprises the optical lens assembly according to any one of claims 1 to 5.

7. The rod mirror system according to claim 6, characterized in that The rod lens system includes a plurality of optical lens groups sequentially arranged along a direction from the object plane to the imaging plane.

8. The rod mirror system according to claim 7, characterized in that The rod lens system includes an odd number of optical lens groups arranged in sequence along a direction from the object plane to the imaging plane.

9. The rod mirror system according to claim 8, characterized in that The distance between every two adjacent optical lens groups is set to be the same.

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