Medical exterior mirror light path system

Abstract

An objective lens system, a rod lens system and an eyepiece system are sequentially arranged from an objective lens seat to an eyepiece seat, the objective lens system is sequentially provided with a right-angle prism, a first objective lens, a second objective lens and a third objective lens from the object space to the image space, the right-angle prism is located on the front side of the first objective lens, and the second objective lens is located on the front side of the third objective lens. The eyepiece system is sequentially provided with a first eyepiece, a second eyepiece and a Dove prism from the object space to the image space. The utility model has the advantages of no aberration, consistent imaging and improved resolution.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical systems of medical instruments, and in particular relates to an optical path system of a medical exoscopic mirror. Background Art

[0002] The exoscope, also known as the endoscope, is a new type of medical optical device. The exoscope is mounted on a miniature pneumatic arm on a portable base. A small orientable camera is mounted on the eyepiece mount of the exoscope, and the objective mount faces the surgical area, thus providing a telescopic view of the surgical field.

[0003] The optical path system of the exoscopic scopes currently on the market generally has multiple groups of rod mirror systems. The axial chromatic aberration will be multiplied, which will eventually lead to unclear images during surgery. At the same time, other aberrations cannot be balanced and multiple focusing is required. At the same time, the existing rod mirror system is a group of glued lenses. The more glued components, the more difficult it is to control the eccentricity. The eccentricity is closely related to the image quality of the entire scope. In addition, the optical path system design of the existing exoscopic scope is too complicated and requires multiple reflections, which will produce aberrations in the final image. Therefore, it is necessary to provide an optical path system for an exoscopic scope that does not produce aberrations, has consistent imaging, and improves resolution. Utility Model Content

[0004] The utility model aims to provide a medical exoscopic optical path system, which has the advantages of no aberration, consistent imaging and improved resolution.

[0005] The technical solution of the utility model is as follows: a medical exoscopic optical path system, wherein an objective system, a rod lens system and an eyepiece system are sequentially arranged from an objective lens seat to an eyepiece seat, wherein the objective lens system is sequentially provided with a right-angle prism, a first objective lens, a second objective lens and a third objective lens from the object side to the image side, wherein the right-angle prism is located in front of the first objective lens, and the eyepiece system is sequentially provided with a first eyepiece, a second eyepiece and a Dove prism from the object side to the image side.

[0006] In the aforementioned medical exoscopic optical path system, the first objective lens is a plano-convex lens with uniform refractive index, the second objective lens is a convex lens with negative optical power, and the third objective lens is a convex lens with positive optical power. The purpose of using them in combination is to overcome the imaging defects of a single lens and improve the optical quality of the objective lens. The first eyepiece is a converging lens to make the image brightness uniform, and the second eyepiece is an eyepiece lens to magnify the image.

[0007] In the aforementioned medical exoscopic optical path system, the rod mirror system is a pair of symmetrically installed rod mirror groups, and the rod mirror group is a first lens, a second lens and a third lens that are glued to each other.

[0008] In the aforementioned medical exoscopic optical path system, the rod mirror system satisfies the following condition: 30≤T / D≤40, where T is the conjugate distance of the object-image conjugate plane of the rod mirror system, and D is the diameter of the first lens.

[0009] In the aforementioned medical exoscopic optical path system, the first lens satisfies the following conditions: n 1≤2.1, 25≥V 1≥30, wherein n 1 is the refractive index of the first lens, and V 1 is the Abbe number of the first lens.

[0010] The second lens satisfies the following conditions: n 2≥1.6, 40≥V 2≥30, wherein n 2 is the refractive index of the second lens, and V 2 is the Abbe number of the second lens.

[0011] The third lens satisfies the following conditions: 1.65≥n3≥1.54, V 3≥40, wherein n3 is the refractive index of the third lens, and V3 is the Abbe number of the third lens.

[0012] Compared with the prior art, the utility model has the following advantages:

[0013] The right-angle prism in the utility model is located at the front side of the first objective lens and at the front of the object image. The optical path is a parallel optical path and does not generate aberration.

[0014] At the same time, the right-angle prism and the Dove prism are reflected twice and the images are consistent.

[0015] Furthermore, the rod mirror adopts an asymmetric structure of three glued lenses, namely the first lens, the second lens and the third lens, which is beneficial to correcting chromatic aberration, balancing other aberrations and improving resolution.

[0016] In summary, the utility model has the advantages of no aberration, consistent imaging and improved resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the exterior mirror of the utility model;

[0018] Figure 2 It is a schematic diagram of the structure of the optical path system of the utility model;

[0019] Figure 3 It is a schematic diagram of the light propagation structure of the utility model.

[0020] The marks in the accompanying drawings are: 1-objective lens system, 11-right angle prism, 12-first objective lens, 13-second objective lens, 14-third objective lens, 2-rod lens system, 20-rod lens group, 21-first lens, 22-second lens, 23-third lens, 3-eyepiece system, 31-first eyepiece, 32-second eyepiece, 33-Dove prism, A-objective lens mount, B-eyepiece mount. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further specifically described below through embodiments and in combination with the accompanying drawings, but it is not intended to limit the present invention.

[0022] Embodiment 1. A medical exoscopic optical system, such as Figure 1-3 As shown, an objective lens system 1, a rod lens system 2 and an eyepiece system 3 are sequentially arranged from the objective lens seat A to the eyepiece seat B. The objective lens system 1 is sequentially provided with a right-angle prism 11, a first objective lens 12, a second objective lens 13 and a third objective lens 14 from the object side to the image side. The right-angle prism 11 is located in front of the first objective lens 12. The eyepiece system 3 is sequentially provided with a first eyepiece 31, a second eyepiece 32 and a dove prism 33 from the object side to the image side. The right-angle prism 11 causes the image to be reflected once so that the optical path is parallel. The dove prism 33 causes the light to be reflected so that the image is an erect image.

[0023] The rod mirror system 2 is a pair of symmetrically mounted rod mirror groups 20, wherein the rod mirror group 20 is a first lens 21, a second lens 22 and a third lens 23 glued together. The rod mirror system satisfies 30≤T / D≤40(1), wherein T is the conjugate distance of the object-image conjugate plane of the rod mirror system, and D is the diameter of the first lens.

[0024] Because the main function of the rod mirror system is to efficiently transmit images within a limited physical aperture, if the object-image conjugate distance of the rod mirror system is too long, the numerical aperture of the light beam will inevitably be reduced under the rated lens diameter. If the object-image conjugate distance is too short, the number of rod mirror groups required within a specific physical length will increase, affecting the light transmission efficiency and cost. Therefore, the rod mirror system is limited by formula (1) to improve the image transmission capability of the rod mirror system and reduce the cost. In this embodiment, there are two glued rod mirror groups 20, which can better control the eccentricity and improve the imaging quality.

[0025] The first lens n 1=2, V 1=25, wherein n 1 is the refractive index of the first lens, and V 1 is the Abbe number of the first lens.

[0026] The first lens is a long rod lens, and its spectral transmittance will affect the color perception of the entire lens when used for observation. Glass with too high a refractive index has a strong absorption rate for blue light, making the imaging effect of the entire lens yellow. Therefore, the optical glass material used for the first lens is H-ZLAF90, which can further improve the imaging quality.

[0027] The second lens n 2=1.6, V 2=37, wherein n 2 is the refractive index of the second lens, and V 2 is the Abbe number of the second lens.

[0028] The second lens is made of F2 optical glass material with positive focal length, which is conducive to the transmission of imaging and the introduction of large-angle light.

[0029] The third lens n3=1.6, V3=46, wherein n3 is the refractive index of the third lens, and V3 is the Abbe number of the third lens.

[0030] The third lens is made of BAF6 optical glass material with negative optical power, which is beneficial for correcting aberrations. It is also beneficial for correcting the distortion caused by the large-angle light introduced by the second lens, thereby improving the imaging quality.

[0031] The propagation path is: the object image is reflected once from the right-angle prism 11 on the objective lens holder A to become a parallel light path, passes through the first objective lens 12, the second objective lens 13, the fourth objective lens 14, the rod lens system 2, the first eyepiece 31, the second eyepiece 32, and then to the Dove prism 33, and is reflected once by the Dove prism 33 to make the object image straight.

Claims

1. A medical exoscopic optical path system, characterized in that: The invention comprises an objective lens seat (A) and an eyepiece seat (B), wherein an objective lens system (1), a rod lens system (2) and an eyepiece lens system (3) are sequentially arranged from the objective lens seat (A) to the eyepiece seat (B); the objective lens system (1) is sequentially arranged from the object side to the image side with a right-angle prism (11), a first objective lens (12), a second objective lens (13) and a third objective lens (14); the right-angle prism (11) is located in front of the first objective lens (12); and the eyepiece lens system (3) is sequentially arranged from the object side to the image side with a first eyepiece (31), a second eyepiece (32) and a Dove prism (33).

2. The optical path system of a medical exoscopic microscope according to claim 1, characterized in that: The rod lens system (2) is a pair of symmetrically installed rod lens groups (20), and the rod lens group (20) is a first lens (21), a second lens (22) and a third lens (23) that are glued together.

3. The optical path system of a medical exoscopic microscope according to claim 2, characterized in that: The rod mirror system (2) satisfies the following condition: 30≤T / D≤40, wherein T is the conjugate distance of the object-image conjugate plane of the rod mirror system, and D is the diameter of the first lens.

4. The optical path system of a medical exoscopic microscope according to claim 2, characterized in that: The first lens (21) satisfies the following conditions: n1≤2.1, 25≥V1≥30, wherein n1 is the refractive index of the first lens, and V1 is the Abbe number of the first lens.

5. The optical path system of a medical exoscopic microscope according to claim 2, characterized in that: The second lens (22) satisfies the following conditions: n 2≥1.6, 40≥V 2≥30, wherein n 2 is the refractive index of the second lens, and V 2 is the Abbe number of the second lens.

6. The optical path system of a medical exoscopic microscope according to claim 2, characterized in that: The third lens (23) satisfies the following conditions: 1.65≥n3≥1.54, V 3≥40, Wherein n3 is the refractive index of the third lens, and V3 is the Abbe number of the third lens.

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