CN114002837A

CN114002837A - Microscope objective

Info

Publication number: CN114002837A
Application number: CN202111049283.5A
Authority: CN
Inventors: 文里云
Original assignee: Nanjing Kangye Optical Technology Co ltd
Current assignee: Nanjing Kangye Optical Technology Co ltd
Priority date: 2021-09-08
Filing date: 2021-09-08
Publication date: 2022-02-01
Anticipated expiration: 2041-09-08
Also published as: CN114002837B

Abstract

The invention discloses a microscope objective lens, which belongs to the technical field of technical optical instruments, and comprises a first lens from an object space to an image space in sequence: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a first lens group: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a second lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a sixth lens: the object-oriented side is convex, and the image-oriented side is convex; a third lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a fourth lens group: the surface facing the object is convex and the surface facing the image is concave. All lenses of the objective lens are arranged on the same optical axis from the object space to the image space, and the objective lens has high imaging quality and a large observation field of view on the premise of having a large numerical aperture so as to meet the requirements of various fields on the microscope objective lens.

Description

Microscope objective

Technical Field

The invention belongs to the technical field of technical optical instruments, and particularly relates to a microscope objective.

Background

An optical microscope generally comprises an ocular lens, a tube lens, an objective lens, a thick focusing screw, a thin focusing screw, a pressing sheet clamp, a light through hole, a light chopper, a converter, a reflector, an objective table, a lens arm, a lens cone, a lens base, a condenser and a diaphragm. The magnifying power of the microscope depends mainly on the objective lens, the quality of the objective lens and the structure directly affect the image quality of the microscope, which is the main component determining the resolution and the imaging definition of the microscope.

The Numerical Aperture (NA) of an optical system is a measure of the angular range of light that the system is capable of collecting. The precise definition of numerical aperture varies slightly in different fields of optics. In the optical field, the numerical aperture describes the size of the light-receiving cone angle of the lens, and the latter determines the light-receiving capacity and the spatial resolution of the lens; in the field of optical fibers, the numerical aperture describes the magnitude of the cone angle of light entering and exiting the fiber. The numerical aperture is an important parameter of the microscope objective lens, and determines that the resolution of the objective lens has direct relation with the magnification factor, the working distance and the depth of field of the objective lens. At present, various microscope objectives exist worldwide, but the maximum numerical value which can be achieved by the numerical aperture of a 20x objective is only 0.50mm technically, and the imaging quality effect is reduced and the objective cannot be used due to the use of a larger numerical aperture.

To solve the above problems, some solutions have been proposed in the prior art, for example, chinese utility model patent publication No. CN205844615U discloses a microscope 20x objective lens in 2016, 12, 28, which includes five spherical glass lenses arranged along the optical axis, in order from the object space to the image space: a first lens D1, a second lens D2, a third lens D3, a fourth lens D4 and a fifth lens D5, wherein the second lens D2 and the third lens D3 form a cemented lens group; the first lens D1 is concave facing the object space and convex facing the image space; the second lens element D2 is convex toward the object side and concave toward the image side; the third lens element D3 is convex toward the object side and convex toward the image side; the fourth lens element D4 is convex toward the object side and concave toward the image side; the fifth lens element D5 is convex toward the object side and concave toward the image side. Thereby the working distance is longer under the premise of larger numerical aperture. The technical scheme has the disadvantages that the numerical aperture is increased to a certain extent, but the observation field is small, the imaging quality is reduced, and the requirements of various fields on the microscope objective cannot be met. Since the larger the numerical aperture, the more difficult the imaging quality is to control. How to ensure higher imaging quality under the condition of larger numerical aperture, so that the microscope can have wider application range in the industry, and the problem to be solved is urgent.

Disclosure of Invention

1. Technical problem

Aiming at the problems in the prior art, the invention provides the microscope objective lens which has larger numerical aperture and larger observation field under the premise of higher imaging quality.

2. Technical scheme

In order to eliminate the technical problems, the invention adopts the following technical scheme: the invention discloses a microscope objective, which comprises a first lens from an object side to an image side in sequence: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a first lens group: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a second lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a sixth lens: the object-oriented side is convex, and the image-oriented side is convex; a third lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a fourth lens group: the surface facing the object is convex and the surface facing the image is concave. All lenses of the objective lens are arranged on the same optical axis from the object space to the image space, and the objective lens has high imaging quality and a large observation field of view on the premise of having a large numerical aperture so as to meet the requirements of various fields on the microscope objective lens.

Preferably, the first lens group is formed by gluing a second lens and a third lens, and both the second lens and the third lens are concave-convex lenses; the second lens group is formed by gluing a fourth lens and a fifth lens, the fourth lens is a convex lens, and the fifth lens is a concave-convex lens; the third lens group is formed by gluing a seventh lens and an eighth lens, wherein the seventh lens is a concave-convex lens, and the eighth lens is a convex lens; the lens group IV is formed by gluing a ninth lens and a tenth lens, wherein the ninth lens is a convex lens, and the tenth lens is a concave lens;

preferably, the system comprises sixteen mirror surfaces, and the parameters of the mirror surfaces are respectively

The first mirror surface is R1-4.516-4.913 mm, D1-4.30-4.80 mm and phi 1-4.10-4.40 mm;

the second mirror surface is R2-5.650-6.031 mm, D2-0.15-0.35 mm and phi 2-9.10-9.30 mm;

the third mirror surface is R3-8.501-8.912 mm, D3-1.10-1.40 mm and phi 3-9.80-10.20 mm;

the fourth mirror surface is R4-14.015-14.375 mm, D4-5.40-5.80 mm and phi 4-11.90-12.20 mm;

the fifth mirror surface is R5-7.445-7.801 mm, D5-0.18-0.23 mm and phi 5-14.30-14.70 mm;

the sixth mirror surface is R6 ═ 74.628 ~ +76.201mm, D6 ═ 7.30 ~ 7.60mm, Φ 6 ═ 17.40 ~ 17.80 mm;

the seventh mirror surface is R7-9.735-10.225 mm, D7-1.20-1.50 mm and phi 7-17.80-18.20 mm;

the eighth mirror surface is R8-23.052-23.384 mm, D8-0.30-0.60 mm, phi 8-21.20-21.50 mm;

the ninth mirror surface is R9 ═ 37.134 ~ +37.658mm, D9 ═ 6.40-6.80 mm, Φ 9 ═ 24.70-25.00 mm;

the tenth mirror surface is R10-29.355-29.703 mm, D10-0.50-0.80 mm and phi 10-25.40 mm;

the eleventh mirror surface is R11 ═ 19.458 ~ +19.868mm, D11 ═ 1.35 ~ 1.70mm, Φ 11 ═ 24.20 ~ 24.50 mm;

the twelfth mirror surface is R12 ═ 13.535 ~ +13.863mm, D12 ═ 8.80 ~ 9.20mm, Φ 12 ═ 22.10 ~ 22.40 mm;

the thirteenth mirror surface is R13-37.334-37.825 mm, D13-0.45-0.85 mm and phi 13-21.70-22.00 mm;

the fourteenth mirror surface is R14 ═ 17.135 ~ +17.565mm, D14 ═ 4.50 ~ 4.80mm, Φ 14 ═ 18.50 ~ 18.90 mm;

the fifteenth mirror surface is R15-33.425-33.964 mm, D15-1.25-1.65 mm and phi 15-17.65-17.95 mm;

the sixteenth mirror surface is R16 ═ 9.125 ~ +9.565mm, D16 ~ 199-201 mm, Φ 16 ~ 13.20-13.60 mm;

wherein R is the curvature radius, D is the distance between adjacent mirror surfaces, and phi is the effective clear aperture.

Preferably, the focal length of the first lens is 30-40 mm; the focal length of the first lens group is 110-130 mm; the focal length of the second lens group is 155-165 mm; the focal length of the sixth lens is 35-45 mm; the focal length of the lens group III is 35-45 mm; the focal length of the lens group IV is-25 to-35 mm.

Preferably, the

The refractive index/Abbe coefficient of the first lens (110) is 1.88300/40.79;

the refractive index/Abbe coefficient of the second lens (120) is 1.88300/40.79;

the refractive index/Abbe coefficient of the third lens (130) is 1.43335/94.52;

the refractive index/Abbe coefficient of the fourth lens (140) is 1.43335/94.52;

the refractive index/Abbe coefficient of the fifth lens (150) is 1.7552// 27.53;

the refractive index/Abbe coefficient of the sixth lens (160) is 1.43335/94.52;

the refractive index/Abbe coefficient of the seventh lens (170) is 1.88300/40.79;

the refractive index/Abbe coefficient of the eighth lens (180) is 1.43335/94.52;

the refractive index/Abbe coefficient of the ninth lens (190) is 1.80518/25.46;

the refractive index/Abbe's number of the tenth lens (200) is 1.88300/40.79.

Preferably, the field of view of the objective lens is 25mm, and the numerical aperture is more than or equal to 0.8.

Preferably, the mirror surface of the objective lens is spherical.

A microscope comprising the objective lens.

Preferably, the microscope has a tube length of 165mm and a magnification of 20 x.

3. Advantageous effects

Compared with the prior art, the invention has the beneficial effects that:

the invention discloses a microscope objective, which comprises a first lens from an object side to an image side in sequence: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a first lens group: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a second lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a sixth lens: the object-oriented side is convex, and the image-oriented side is convex; a third lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a fourth lens group: the surface facing the object is convex and the surface facing the image is concave. All lenses of the objective lens are arranged on the same optical axis from the object space to the image space, and the objective lens has high imaging quality and a large observation field of view on the premise of having a large numerical aperture so as to meet the requirements of various fields on the microscope objective lens. The numerical aperture of the microscope objective lens is set to be more than 0.8, and the objective lens has good imaging quality and a larger observation field of view through the lens combination, thereby meeting the requirements of various fields on the use of the microscope objective lens.

Drawings

FIG. 1 is a schematic diagram of a microscope objective of the present invention;

FIG. 2 is a table of field parameters for a microscope objective;

FIG. 3 is a diagram of a simulated detection of light dispersion;

FIG. 4 is a graph of energy concentration of monochromatic light based on diffraction;

FIG. 5 is a diagram of an optical transfer function for polychromatic light;

FIG. 6 is a graph comparing wave phase difference with theoretical value;

in the figure: 110. a first lens; 120. a second lens; 130. a third lens; 140. a fourth lens; 150. a fifth lens; 160. a sixth lens; 170. a seventh lens; 180. an eighth lens; 190. a ninth lens; 200. a tenth lens.

Detailed Description

The following detailed description of exemplary embodiments of the invention refers to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration exemplary embodiments in which the invention may be practiced. Although these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be realized and that various changes to the invention may be made without departing from the spirit and scope of the present invention. The following more detailed description of the embodiments of the invention is not intended to limit the scope of the invention, as claimed, but is presented for purposes of illustration only and not limitation to describe the features and characteristics of the invention, to set forth the best mode of carrying out the invention, and to sufficiently enable one skilled in the art to practice the invention. Accordingly, the scope of the invention is to be limited only by the following claims.

The following detailed description is made in conjunction with the accompanying drawings:

as shown in fig. 1, the present invention discloses a microscope objective lens, which comprises a first lens 110 from an object side to an image side (the light incident side is the object side, and the light emergent side is the image side): the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a first lens group: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface; a second lens group: the surface facing the object space is convex, and the surface facing the image space is convex; sixth lens 160: the object-oriented side is convex, and the image-oriented side is convex; a third lens group: the surface facing the object space is convex, and the surface facing the image space is convex; a fourth lens group: the surface facing the object is convex and the surface facing the image is concave. All lenses of the objective lens are arranged on the same optical axis from the object space to the image space, and the objective lens has high imaging quality and a large observation field of view on the premise of having a large numerical aperture so as to meet the requirements of various fields on the microscope objective lens. .

The first lens group is formed by gluing a second lens 120 and a third lens 130, and the second lens 120 and the third lens 130 are both concave-convex lenses; the second lens element 120 is concave toward the object side and convex toward the image side; the third lens element 130 is concave toward the object side and convex toward the image side; the second lens group is formed by gluing a fourth lens 140 and a fifth lens 150, wherein the fourth lens 140 is a convex lens, and is convex towards the object space and convex towards the image space; the fifth lens element 150 is a meniscus lens element, concave toward the object side and convex toward the image side; the third lens group is formed by gluing a seventh lens 170 and an eighth lens 180, wherein the seventh lens 170 is a concave-convex lens, and is convex towards the object side and concave towards the image side; the eighth lens element 180 is a convex lens element, convex toward the object side and convex toward the image side; the fourth lens group is formed by gluing a ninth lens 190 and a tenth lens (200), wherein the ninth lens 190 is a convex lens, and is convex towards the object side and convex towards the image side; the tenth lens element 200 is a concave lens element, and is concave toward the object side and concave toward the image side.

The focal length of the first lens 110 of the microscope objective lens is 30-40 mm, preferably 35.174 mm; the focal length of the first lens group is 110-130 mm, preferably 123.991 mm; the focal length of the second lens group is 155-165 mm, preferably 158.134 mm; the focal length of the sixth lens 160 is 35-45 mm, preferably 38.967 mm; the focal length of the lens group III is 35-45 mm, preferably 41.645 mm; the focal length of the lens group IV is-25 to-35 mm, preferably-27.54 mm.

The microscope objective lens comprises sixteen mirror surfaces with different parameters, wherein the sixteen mirror surfaces are a first mirror surface of a first lens facing an object space from the object space to an image space, the first mirror surface is a concave surface, and a second mirror surface back to the image space is a convex surface.

In the first lens group, a third mirror surface facing the object space is a concave surface; the fourth mirror surface formed by the second lens 120 and the third lens 130 through gluing is concave towards the object space; and the fifth mirror surface facing the image space is a convex surface.

In the second lens group, the sixth mirror surface facing the object space is a convex surface; a seventh mirror surface formed by gluing the fourth lens 140 and the fifth lens 150, which is concave toward the object; an eighth mirror surface facing the image space, which is convex;

the sixth lens faces to the ninth mirror surface of the object space and is a convex surface; the tenth mirror surface facing the image side is a convex surface.

In the third lens group, the eleventh mirror surface facing the object space is a convex surface; a twelfth mirror surface formed by the seventh lens 170 and the eighth lens 180 being cemented to be convex toward the object side; and a thirteenth mirror surface facing the image side, which is convex.

In the fourth lens group, the fourteenth lens surface facing the object space is a convex surface; a fifteenth mirror surface formed by bonding the ninth lens 190 and the tenth lens 200; the object facing side is a concave surface; and a sixteenth mirror surface facing the image side, which is convex.

In the whole lens combination, the mirror surface parameter of the first lens determines the numerical aperture size, and the rest lenses and the lens parameters determine the imaging quality of the objective lens. For better imaging quality, the overall parameter collocation debugging is carried out on all lenses and lens combinations in the objective lens, and the mirror surface parameters of each lens are as follows under the condition of better imaging:

the curvature radius R, the mirror distance D and the effective clear aperture phi of the sixteen mirrors are as follows:

the sixteenth mirror surface is R16 ═ 9.125 ~ +9.565mm, D16 ~ 199-201 mm, Φ 16 ~ 13.20-13.60 mm.

Wherein, the curvature radius R parameter, "+" represents that the mirror surface is convex, and "-" represents that the mirror surface is concave.

The objective lens combined by the lenses in the parameter range is subjected to objective lens imaging quality detection, and the imaging quality is excellent.

The parameters of the first mirror surface and the second mirror surface in the first lens are set as follows: the first mirror surface is R1-4.516-4.913 mm, D1-4.30-4.80 mm and phi 1-4.10-4.40 mm; the second mirror surface is R2-5.650-6.031 mm, D2-0.15-0.35 mm and phi 2-9.10-9.30 mm; the numerical aperture of the objective lens is not less than 0.8 through a numerical aperture calculation formula.

The detection items comprise:

1. simulating and detecting the field point parameters; 2. simulating and detecting the relation of optical path difference under pupil coordinates of the meridian component and the sagittal component; 3. simulating and detecting the diffraction-based energy concentration condition embodied by monochromatic light under a large field of view; 4. simulating and detecting a polychromatic light optical transfer function under a large field of view; 5. and (5) simulating and detecting a comparison graph of the wave aberration and a theoretical value. The better quality of the microscope objective lens is reflected in the detection images and parameters.

The intermediate parameters (as shown in table 1), the first to sixteenth mirror parameters, were selected from the above mirror parameter range, and the imaging quality thereof was examined by simulation of ZEMAX software.

TABLE 1 selection of inspection parameters for first to sixteenth mirror and refractive index/Abbe's number (nD/vD) of Ten lenses

The curvature radius R in the above table is the spherical radius of the mirror surface, the mirror surface distance D is the distance between two adjacent mirror surfaces from the first mirror surface, and the effective clear aperture phi is the aperture value of the effective clear aperture of each mirror surface when the image-side numerical aperture of the objective lens is 0.8. It should be noted that the microscope object of the present invention is a 20 × objective lens, which is used in conjunction with a lens with a tube diameter F of 165mm (infinite system lens), and has the characteristics of long working distance, high resolution, small volume, etc.

In order to further check the imaging quality of the objective lens, the imaging effect of the microscope objective lens is simulated and detected by ZEMAX software from the following aspects.

Simulating and detecting field point parameters

As shown in fig. 2, it is shown in ZEMAX that the half field angle measured can reach 12.5mm, and the field angle can reach 25 mm.

Simulating and detecting the relation of optical path difference under the pupil coordinate of the meridian component and the sagittal component

As shown in fig. 3, the optical path difference curve under pupil coordinates of the meridional component and the sagittal component of the light with different wavelengths (unit: nm) under several different viewing field conditions is simulated and imaged:

a first set of simulated imaging: the field of view point is 0.00mm, and the light wavelengths are 0.644, 0.546, 0.480 and 0.436 respectively.

A second set of simulated imaging: the field of view point is 8.50mm, and the light wavelengths are 0.644, 0.546, 0.480 and 0.436 respectively.

A third set of simulated imaging: the field of view point is 12.02mm, and the light wavelengths are 0.644, 0.546, 0.480 and 0.436 respectively.

And a fourth group of simulation imaging: the field of view point is 14.72mm, and the light wavelengths are 0.644, 0.546, 0.480 and 0.436 respectively.

And a fifth group of simulation imaging: the field of view point is 20.00mm, and the light wavelengths are 0.644, 0.546, 0.480 and 0.436 respectively.

In the figure, the left side of the same group is a meridian component pupil coordinate lower optical path difference curve graph, the right side is a sagittal component pupil coordinate lower optical path difference curve graph, in the meridian component pupil coordinate lower optical path difference curve graph or the sagittal component pupil coordinate lower optical path difference curve graph, curves of light with the wavelengths of 0.644, 0.546, 0.480 and 0.436 from bottom to top are close to the abscissa axis, the optical path difference is good, the dispersion condition of the whole field of view is good, and the microscope objective lens has high imaging quality.

And thirdly, simulating and detecting the diffraction-based energy concentration condition embodied by the monochromatic light under the large visual field.

To further examine the microscope objective imaging quality, the diffraction-based energy concentration condition exhibited by monochromatic light under a large field of view was simulated in the ZEMAX software, as shown in fig. 4. In the figure, when each curve is intersected with the datum line from bottom to top, each curve respectively represents the relationship between the energy percentage of the field of view and the radius of the light spot when the field of view point is 20.00mm, 14.72mm, 12.02mm, 8.50mm and 0.00mm, and the uppermost curve (the relationship between the energy percentage and the radius of the light spot under the ideal condition) is taken as a reference.

Fourth, simulating and detecting the multi-color optical transfer function under large visual field

As shown in fig. 5, the curves are transfer functions of the meridional component or the sagittal component; making a reference line, intersecting each curve with the reference line from bottom to top,

the first curve represents the transfer function of the meridional component with a field of view point of 14.72 mm;

the second curve represents the transfer function of the meridional component with a field of view point of 12.02 mm;

the third curve represents the transfer function of the meridional component with a field of view point of 20.00 mm;

the fourth curve represents the transfer function of the meridional component with a field of view point of 8.50 mm;

the fifth curve represents the transfer function of the sagittal component with a field-of-view point of 20.00 mm;

the sixth curve represents the transfer function for the sagittal component with a field of view point of 14.72 mm;

the seventh curve represents the transfer function of the sagittal component with a field-of-view point of 12.02 mm;

the eighth curve represents the transfer function of the sagittal component with a field-of-view point of 8.50 mm;

the ninth curve represents the transfer function for the meridional and sagittal components with a field of view point of 0.00 mm.

The tenth curve (the uppermost curve) is a transfer function curve under an ideal condition, and it can be seen from the figure that the transfer functions of the meridional component and the sagittal component at each field point are relatively close to each other, so that the contrast of the whole field of the microscope objective lens is relatively good, and the objective lens has relatively high imaging quality.

Fifth, simulation detection wave aberration and theoretical value comparison diagram

As shown in fig. 6, the wave aberration is an important index of the imaging quality of the detection system, and the smaller the wave aberration, the better the imaging quality. As can be seen from the figure, the difference between the actual wave surface and the ideal spherical wave is extremely small, and the imaging effect is close to perfect.

The microscope objective lens provided by the invention has excellent imaging quality while adjusting the mirror surface parameters of the first lens to enable the first lens to reach the numerical aperture of 0.8, and the observation field of view of the microscope objective lens can reach 25mm, thereby meeting the requirements of various fields on the microscope objective lens. And the microscope objective lens adopts all spherical glass lenses, can be compatible with the optical lens processing and detecting process in the prior art, and has better applicability.

The present invention and its embodiments have been described above schematically, without limitation, and what is shown in the drawings is only one of the embodiments of the present invention, and the actual structure is not limited thereto. Therefore, if the person skilled in the art receives the teaching, without departing from the spirit of the invention, the person skilled in the art shall not inventively design the similar structural modes and embodiments to the technical solution, but shall fall within the scope of the invention.

Claims

1. A microscope objective, characterized by: the objective lens comprises an object side and an image side in sequence

First lens (110): the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface;

a first lens group: the surface facing the object space is a concave surface, and the surface facing the image space is a convex surface;

a second lens group: the surface facing the object space is convex, and the surface facing the image space is convex;

sixth lens (160): the object-oriented side is convex, and the image-oriented side is convex;

a third lens group: the surface facing the object space is convex, and the surface facing the image space is convex;

a fourth lens group: the surface facing the object is convex and the surface facing the image is concave.

2. Microscope objective according to claim 1,

the first lens group is formed by gluing a second lens (120) and a third lens (130), and the second lens (120) and the third lens (130) are both concave-convex lenses;

the second lens group is formed by gluing a fourth lens (140) and a fifth lens (150), the fourth lens (140) is a convex lens, and the fifth lens (150) is a concave-convex lens;

the third lens group is formed by gluing a seventh lens (170) and an eighth lens (180), the seventh lens (170) is a concave-convex lens, and the eighth lens (180) is a convex lens;

the fourth lens group is formed by gluing a ninth lens (190) and a tenth lens (200), wherein the ninth lens (190) is a convex lens, and the tenth lens (200) is a concave lens.

3. Microscope objective according to claim 1, characterized in that it comprises sixteen mirror surfaces, the mirror surface parameters being in each case

4. A microscope objective according to claim 1, characterized in that: the above-mentioned

The focal length of the first lens (110) is 30-40 mm;

the focal length of the first lens group is 110-130 mm;

the focal length of the second lens group is 155-165 mm;

the focal length of the sixth lens (160) is 35-45 mm;

the focal length of the lens group III is 35-45 mm;

the focal length of the lens group IV is-25 to-35 mm.

5. A microscope objective according to any one of claims 1 to 4, characterized in that: the above-mentioned

The refractive index/Abbe coefficient of the first lens (110) is 1.88300/40.79;

the refractive index/Abbe coefficient of the third lens (130) is 1.43335/94.52;

the refractive index/Abbe coefficient of the sixth lens (160) is 1.43335/94.52;

the refractive index/Abbe coefficient of the ninth lens (190) is 1.80518/25.46;

the refractive index/Abbe's number of the tenth lens (200) is 1.88300/40.79.

6. A microscope objective according to any one of claims 1 to 4, wherein the mirror surfaces of the objective are spherical.

7. Microscope objective according to any one of claims 1 to 4, characterized in that the field of view of the objective is 25mm and the numerical aperture is ≥ 0.8.

8. A microscope comprising an objective lens according to any of claims 1 to 7.

9. The microscope of claim 9, wherein the microscope has a tube length of 165mm and a magnification of 20 x.