Microobjective and optical system thereof

Abstract

The invention relates to a microscope objective and an optical system of the microscope objective. The optical system of the microscope objective comprises a first lens group with positive refractive power, a second lens group with positive refractive power and a third lens group with positive or negative refractive power which are sequentially arranged from the object side to the image side. The first lens group at least comprises one or more optical elements with positive refractive power, the second lens group at least comprises two or more optical elements with positive refractive power, and the Abbe number of materials of the optical elements is larger than a first threshold value. According to the optical system of the microscope objective, the abbe numbers of optical element materials in the first lens group and the second lens group are set, so that the full wave band of the optical system of the microscope objective can work; due to the arrangement of the first lens group, the second lens group and the third lens group, the optical system of the microscope objective has high resolution, chromatic aberration correction of visible light full wave bands is achieved, and meanwhile the characteristics of small field curvature and small distortion are kept.

Description

Technical Field

[0001] The present application relates to the technical field of microscopes, and in particular to a microscope objective lens and an optical system of the microscope objective lens. Background Art

[0002] In the field of microscopy, in addition to using eyepieces for visual observation, the use of digital cameras to obtain microscope images for observation and analysis is expanding significantly. In recent years, the demand for high-resolution, large-field-of-view, and large-aperture microscope objectives has increased. The existing microscope with ordinary apochromatic function has a magnification of 20, a numerical aperture NA=0.75, an object field of view of 1.25mm, and a working distance of 0.677mm, but the numerical aperture of the microscope is not large enough, the resolution is not high enough, the working distance is not long enough, and the working band is too small, resulting in low resolution and large distortion of the microscope. Summary of the invention

[0003] The present application provides a microscope objective lens and an optical system of the microscope objective lens, which are used to solve the technical problems of existing microscopes, such as insufficient numerical aperture, insufficient resolution, insufficient working distance, and too small working band.

[0004] In order to achieve the above objectives, this application provides the following technical solutions:

[0005] In one aspect, an optical system of a microscope objective lens is provided, comprising a first lens group with positive refractive power, a second lens group with positive refractive power, and a third lens group with positive or negative refractive power, which are sequentially arranged from the object side to the image side;

[0006] The first lens group includes at least one or more optical elements with positive refractive power, the second lens group includes at least two or more optical elements with positive refractive power, and the Abbe number of the material of the optical elements is greater than a first threshold.

[0007] Preferably, the ratio of the focal length of the first lens group to the focal length of the optical system is greater than a second threshold and less than a third threshold; the ratio of the focal length of the second lens group to the focal length of the optical system is greater than a fourth threshold and less than a fifth threshold; the ratio of the focal length of the third lens group to the focal length of the optical system is greater than a sixth threshold and less than a seventh threshold; and the ratio of the length formed by the first lens group, the second lens group and the third lens group to the focal length of the optical system is greater than an eighth threshold and less than a ninth threshold.

[0008] Preferably, the second threshold is 0.9, the third threshold is 1.2, the fourth threshold is 7.0, the fifth threshold is 15.0, the sixth threshold is -30, the seventh threshold is 40, the eighth threshold is 5.0, and the ninth threshold is 5.8.

[0009] Preferably, a ratio of a distance from the object side to the first lens group to a focal length of the optical system is less than a tenth threshold; a ratio of a distance from the first lens group to the second lens group to a focal length of the optical system is less than an eleventh threshold; and a ratio of a distance from the second lens group to the third lens group to a focal length of the optical system is less than a twelfth threshold.

[0010] Preferably, the tenth threshold is 0.12, the eleventh threshold is 0.4, and the twelfth threshold is 0.3.

[0011] Preferably, the first threshold is 70.

[0012] Preferably, the first lens group includes a first optical element with negative refractive power, a second optical element with positive refractive power and a third optical element with positive refractive power, which are arranged in sequence from the object side to the image side; and / or, the second lens group includes a fourth optical element with positive refractive power and a fifth optical element with negative refractive power, which are arranged in sequence from the object side to the image side; and / or, the third lens group includes a sixth optical element with negative refractive power and a seventh optical element with positive refractive power, which are arranged in sequence from the object side to the image side.

[0013] Preferably, the first optical element is a lens or a first cemented lens, the second optical element is a lens, and the third optical element is a lens or a first cemented lens; and / or, the fourth optical element is a second cemented lens, and the fifth optical element is a first cemented lens; and / or, the sixth optical element is a first cemented lens, and the seventh optical element is a lens.

[0014] Preferably, the first cemented lens is a cemented lens composed of two lenses; and / or the second cemented lens is a cemented lens composed of two or more lenses.

[0015] On the other hand, a microscope objective lens is provided, comprising the optical system of the microscope objective lens described above, wherein the distortion of the microscope objective lens is controlled within a range of -1% to 1%.

[0016] The microscope objective lens and the optical system of the microscope objective lens, the optical system of the microscope objective lens comprises a first lens group with positive refractive power, a second lens group with positive refractive power and a third lens group with positive or negative refractive power which are arranged in sequence from the object side to the image side; the first lens group comprises at least one or more optical elements with positive refractive power, the second lens group comprises at least two or more optical elements with positive refractive power, and the Abbe number of the material of the optical elements is greater than a first threshold value.

[0017] It can be seen from the above technical solutions that the present application has the following advantages: the optical system of the microscope objective lens can work in the full band by setting the Abbe number of the optical element material in the first lens group and the second lens group; the setting of the first lens group, the second lens group and the third lens group makes the optical system of the microscope objective lens have high resolution, realizes chromatic aberration correction in the full band of visible light, and maintains the characteristics of small field curvature and small distortion; solves the technical problems of existing microscopes such as insufficient numerical aperture, insufficient resolution, insufficient working distance and too small working band.

[0018] The microscope objective lens limits the focal distance of the first lens group, the second lens group, and the third lens group, so that the microscope objective lens can achieve a longer working distance under the condition of a large numerical aperture, and use a smaller number of lenses, while preliminarily correcting the spherical aberration, field curvature, and distortion. The microscope objective lens further corrects the aberration by limiting the intervals between the first lens group, the second lens group, and the third lens group. The microscope objective lens limits the Abbe number of the material of each optical element in the first lens group, the second lens group, and the third lens group, and corrects the chromatic aberration of the microscope objective lens in the full band of visible light. Thus, the microscope objective lens can achieve a larger numerical aperture, a longer working distance, and chromatic aberration correction in the full band of visible light, while having the characteristics of good flat field, small distortion, and high resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0020] Figure 1 It is a schematic structural diagram of the optical system of the microscope objective lens described in the embodiment of the present application;

[0021] Figure 2 It is a schematic structural diagram of an optical system of a microscope objective lens according to another embodiment of the present application;

[0022] Figure 3 The optical system of the microscope objective lens described in the embodiment of the present application Figure 1 Field curvature plots of structures;

[0023] Figure 4 The optical system of the microscope objective lens described in the embodiment of the present application Figure 1 Distortion map of the structure;

[0024] Figure 5 The optical system of the microscope objective lens described in the embodiment of the present application Figure 2 Field curvature plots of structures;

[0025] Figure 6 The optical system of the microscope objective lens described in the embodiment of the present application Figure 2 Distortion diagram of the structure. DETAILED DESCRIPTION

[0026] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0027] In the description of the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0028] In the embodiments of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0029] The embodiments of the present application provide a microscope objective and an optical system of the microscope objective, which solve the technical problems of existing microscopes such as insufficient numerical aperture, insufficient resolution, insufficient working distance, and too small working band.

[0030] Embodiment 1:

[0031] Figure 1 It is a schematic diagram of the structure of the optical system of the microscope objective lens described in the embodiment of the present application.

[0032] like Figure 1 As shown, an embodiment of the present application provides an optical system of a microscope objective lens, including a first lens group G1 with positive refractive power, a second lens group G2 with positive refractive power, and a third lens group G3 with positive or negative refractive power, which are arranged in sequence from the object side to the image side.

[0033] It should be noted that the first lens group G1 , the second lens group G2 , and the third lens group G3 are sequentially arranged from the object side to the image side to form an optical system of the microscope objective.

[0034] In the embodiment of the present application, the first lens group G1 includes at least one or more optical elements with positive refractive power, and the second lens group G2 includes at least two or more optical elements with positive refractive power, and the Abbe number of the material of the optical elements is greater than the first threshold.

[0035] It should be noted that the first threshold value can be 70. The optical element can be selected as a lens. In the present embodiment, the Abbe number of the material of the optical element is set by the first lens group G1 and the second lens group G2, so that the optical system of the microscope objective has the ability to correct chromatic aberration in the full band of visible light. Among them, because the Abbe number affects the chromatic aberration correction of the optical system of the microscope objective in the full band of visible light, by including at least one or more lenses with positive refractive power in the first lens group G1, the Abbe number V of the lens material is greater than 70; in the second lens group G2, at least two or more lenses with positive refractive power, the Abbe number V of the lens material is greater than 70; the optical system of the microscope objective can work in the full band of visible light. In other embodiments, the first threshold value can also be set as required.

[0036] The present application provides an optical system of a microscope objective lens, comprising a first lens group with positive refractive power, a second lens group with positive refractive power, and a third lens group with positive or negative refractive power, which are sequentially arranged from the object side to the image side; the first lens group includes at least one or more optical elements with positive refractive power, and the second lens group includes at least two or more optical elements with positive refractive power, and the Abbe number of the material of the optical element is greater than a first threshold. The optical system of the microscope objective lens can work in the full band by setting the Abbe number of the optical element material in the first lens group and the second lens group; the optical system of the microscope objective lens has a high resolution by adopting the arrangement of the first lens group, the second lens group, and the third lens group, and realizes chromatic aberration correction of the full band of visible light, while maintaining the characteristics of small field curvature and small distortion; the technical problems of the existing microscopes, such as insufficient numerical aperture, insufficient resolution, insufficient working distance, and too small working band, are solved.

[0037] In one embodiment of the present application, the ratio of the focal length of the first lens group G1 to the focal length of the optical system is greater than the second threshold and less than the third threshold; the ratio of the focal length of the second lens group G2 to the focal length of the optical system is greater than the fourth threshold and less than the fifth threshold; the ratio of the focal length of the third lens group G3 to the focal length of the optical system is greater than the sixth threshold and less than the seventh threshold; the ratio of the length formed by the first lens group G1, the second lens group G2 and the third lens group G3 to the focal length of the optical system is greater than the eighth threshold and less than the ninth threshold.

[0038] It should be noted that the second threshold value may be 0.9, the third threshold value may be 1.2, the fourth threshold value may be 7.0, the fifth threshold value may be 15.0, the sixth threshold value may be -30, the seventh threshold value may be 40, the eighth threshold value may be 5.0, and the ninth threshold value may be 5.8. In this embodiment, in order to make the optical system of the microscope objective have a large numerical aperture, a long working distance, and a small number of lenses, the optical system of the microscope objective needs to meet the following first constraint condition, which is:

[0039] 0.9 <fG1 / f<1.2

[0040] 7.0 <fG2 / f<15.0

[0041] -30 <fG3 / f<40

[0042] 5.0 <L / f<5.8

[0043] Wherein, f is the focal length of the optical system, fG1 is the focal length of the first lens group, fG2 is the focal length of the second lens group, fG3 is the focal length of the third lens group, and L is the length formed by the first lens group G1, the second lens group G2 and the third lens group G3. L can also be understood as the total length of the optical system of the microscope objective. Among them, because fG1 affects the numerical aperture of the optical system of the microscope objective, fG2 affects the chromatic aberration of the optical system of the microscope objective, and fG3 affects the field curvature of the optical system of the microscope objective, the optical system of the microscope objective has the characteristics of large numerical aperture and long working distance through the first constraint condition defined, and the optical system of the microscope objective uses fewer lenses, thereby reducing the cost of the optical system of the microscope objective.

[0044] Figure 2 It is a schematic structural diagram of an optical system of a microscope objective lens according to another embodiment of the present application.

[0045] In one embodiment of the present application, the first lens group G1 includes a first optical element L1 with negative refractive power, a second optical element L2 with positive refractive power, and a third optical element L3 with positive refractive power, which are sequentially arranged from the object side to the image side; and / or, the second lens group G2 includes a fourth optical element L4 with positive refractive power and a fifth optical element L5 with negative refractive power, which are sequentially arranged from the object side to the image side; and / or, the third lens group G3 includes a sixth optical element L6 with negative refractive power and a seventh optical element L7 with positive refractive power, which are sequentially arranged from the object side to the image side. Wherein, the ratio of the distance from the object side to the first lens group G1 to the focal length of the optical system is less than the tenth threshold value; the ratio of the distance from the first lens group G1 to the second lens group G2 to the focal length of the optical system is less than the eleventh threshold value; and the ratio of the distance from the second lens group G2 to the third lens group G3 to the focal length of the optical system is less than the twelfth threshold value.

[0046] It should be noted that the tenth threshold value may be 0.12, the eleventh threshold value may be 0.4, and the twelfth threshold value may be 0.3. Figure 1 As shown, the first optical element L1 is selected as a lens, the second optical element L2 is selected as a lens, the third optical element L3 is selected as a first cemented lens; the fourth optical element L4 is selected as a second cemented lens, the fifth optical element L5 is selected as a first cemented lens; the sixth optical element L6 is selected as a first cemented lens, and the seventh optical element L7 is selected as a lens. Figure 2 As shown, the first optical element L1 is selected as the first cemented lens, the second optical element L2 is selected as the lens, and the third optical element L3 is selected as the lens; the fourth optical element L4 is selected as the second cemented lens, the fifth optical element L5 is selected as the first cemented lens; the sixth optical element L6 is selected as the first cemented lens, and the seventh optical element L7 is selected as the lens. In order to make the optical system of the microscope objective have high resolution, realize chromatic aberration correction of the full band of visible light, and maintain the characteristics of small field curvature and small distortion, the optical system parameters of the microscope objective must meet the following second constraint condition, which is:

[0047] d1 / f<0.12

[0048] d2 / f<0.4

[0049] d3 / f<0.3

[0050] Wherein, d1 is the distance from the object side to the first lens group, d2 is the distance from the first lens group to the second lens group, d3 is the distance from the second lens group to the third lens group, and f is the focal length of the optical system.

[0051] In the embodiment of the present application, the first cemented lens is a cemented lens composed of two lenses; the second cemented lens is a cemented lens composed of two or more lenses.

[0052] Figure 3 The optical system of the microscope objective lens described in the embodiment of the present application Figure 1 Field curvature diagram of the structure, Figure 4 The optical system of the microscope objective lens described in the embodiment of the present application Figure 1 Distortion diagram of the structure, Figure 5 The optical system of the microscope objective lens described in the embodiment of the present application Figure 2 Field curvature diagram of the structure, Figure 6 The optical system of the microscope objective lens described in the embodiment of the present application Figure 2 Distortion diagram of the structure. Figure 3 and Figure 5 The horizontal axis is the object plane offset, in mm. Figure 3 and Figure 5 The vertical axis is the normalized field of view, with a maximum value of 1. Figure 3 and Figure 5 The solid line represents the sagittal plane of the light. Figure 3 and Figure 5 The dotted line represents the meridian plane of the light. Figure 4 and Figure 6 The horizontal axis is the distortion, unit is %. Figure 4 and Figure 6 The vertical axis is the normalized field of view, with a maximum value of 1.

[0053] In the embodiment of the present application, the optical system of the microscope objective lens is described using the following two cases. Case 1: Figure 1 As shown, the optical system of the microscope objective lens includes an object plane, a first lens group G1, a second lens group G2 and a third lens group G3, and the object side numerical aperture NA of the optical system of the microscope objective lens is set to 0.8, the object side field of view is 1.25 mm, the focal length f is 9 mm, the working distance is 0.81 mm, and the magnification is 20X. The parameters of the optical system of the microscope objective lens are shown in Table 1.

[0054] Table 1 is the parameters of the optical system of the microscope objective lens in Example 1

[0055]

[0056] According to the parameters in Table 1, we obtain fG1 / f=1.0, fG2 / f=8.3, fG3 / f=-23.6, L / f=5.3, d1 / f=0.09, d2 / f=0.31, d3 / f=0.17, the material Abbe number VL2 of the second optical element L2=81.6, the focal length fL2 of the second optical element L2=22.6 mm, the material Abbe number VL=71.3 of the third lens, the focal length fL=13.4 mm, the material Abbe number VL=71.3 of the sixth lens, the focal length fL=15.2 mm of the sixth lens in the fourth optical element L4, the material Abbe number VL=81.6 of the eighth lens in the fifth optical element L5, and the focal length fL=16.3 mm of the eighth lens in the fifth optical element L5. According to the above, in the optical system of the microscope objective lens of this embodiment, the focal length of the first lens group G1 is 9.2 mm, the focal length of the second lens group G2 is 74.5 mm, and the focal length of the third lens group G3 is -212 mm. Figure 1 It can be seen that, from the object side to the image side, there are: a first lens L1 with negative refractive power, a second lens L2 with positive refractive power, a third optical element L3 consisting of a third lens with positive refractive power and a fourth lens with negative refractive power, a fourth optical element L4 consisting of a fifth lens with negative refractive power and a sixth lens with positive refractive power, a fifth optical element L5 consisting of a seventh lens with negative refractive power and an eighth lens with positive refractive power, a sixth optical element L6 consisting of a ninth lens with positive refractive power and a tenth lens with negative refractive power, and an eleventh lens L7 with positive refractive power. The third lens and the fourth lens are combined to form the third optical element L3 of the cemented lens group, and the focal length of the third optical element L3 is 32.3mm. The fifth lens and the sixth lens are combined to form the fourth optical element L4 of the cemented lens group, and the focal length of the fourth optical element L4 is 53.6mm. The seventh lens and the eighth lens are combined to form the fifth optical element L5 of the cemented lens group, and the focal length of the fifth optical element L5 is -178mm. The ninth lens and the tenth lens are combined to form the sixth optical element L6 of the cemented lens group, and the focal length of the sixth optical element L6 is -24.3mm. Figure 3 The distribution of field curvature shows that the field curvature of the optical system of the microscope objective with large numerical aperture and large field of view is controlled within ±0.7 mm, indicating that the optical system of the microscope objective has a good flat field. Figure 4 It can be seen from the distribution of distortion that the distortion of the optical system of the microscope objective is controlled within ±1%, indicating that the optical system of the microscope objective has relatively small distortion.

[0057] In the embodiment of the present application, case 2: Figure 2As shown, the optical system of the microscope objective lens includes an object plane, a first lens group G1, a second lens group G2 and a third lens group G3, and the object numerical aperture NA of the optical system of the microscope objective lens is set to 0.8, the object field of view is 1.25 mm, the focal length f is 9 mm, the working distance is 0.84 mm, and the magnification is 20X. The parameters of the optical system of the microscope objective lens are shown in Table 2.

[0058] Table 2 is the parameters of the optical system of the microscope objective lens in Example 2

[0059]

[0060] According to the parameters in Table 1, we obtain fG1 / f=1.1, fG2 / f=13.6, fG3 / f=-34.8, L / f=5.5, d1 / f=0.09, d2 / f=0.02, d3 / f=0.13, the material Abbe number VL3 of the third optical element L3=81.6, the focal length fL3 of the third optical element L3=28.3 mm, the material Abbe number VL of the seventh lens in the fourth optical element L4=81.6, the focal length fL of the seventh lens in the fourth optical element L4=21.9 mm, the material Abbe number VL of the ninth lens in the fifth optical element L5=81.6, the focal length fL of the ninth lens in the fifth optical element L5=21.9 mm, and the focal length fL of the eighth lens in the fifth optical element L5=16.3 mm. According to the above, in the optical system of the microscope objective lens of this embodiment, the focal length of the first lens group G1 is 9.5 mm, the focal length of the second lens group G2 is 122 mm, and the focal length of the third lens group G3 is 313 mm. Figure 2 It can be seen that, from the object side to the image side, there are: a first optical element L1 consisting of a first lens with negative refractive power and a second lens with positive refractive power, a second optical element L2 with positive refractive power, a third optical element L3 with positive refractive power, a fourth optical element L4 consisting of a fifth lens with positive refractive power, a sixth lens with negative refractive power and a seventh lens with positive refractive power, a fifth optical element L5 consisting of an eighth lens with negative refractive power and a ninth lens with positive refractive power, a sixth optical element L6 consisting of a tenth lens with positive refractive power and an eleventh lens with negative refractive power, and a seventh optical element L7 with positive refractive power. The first lens and the second lens are combined to form the first optical element L1 of the cemented lens group, and the focal length of the first optical element L1 is -32.8mm. The fifth lens, the sixth lens and the seventh lens are combined to form the fourth optical element L4 of the cemented lens group, and the focal length of the fourth optical element L4 is 71.0mm. The eighth lens and the ninth lens are combined to form the fifth optical element L5 of the cemented lens group, and the focal length of the fifth optical element L5 is -149mm. The tenth lens and the eleventh lens are combined to form the sixth optical element L6 of the cemented lens group, and the focal length of the sixth optical element L6 is -41.4mm. Figure 5The distribution of field curvature shows that the field curvature of the optical system of the microscope objective with large numerical aperture and large field of view is controlled within ±1.0 mm, indicating that the optical system of the microscope objective has a good flat field. Figure 6 From the distribution of distortion, it can be seen that the distortion of the optical system of the microscope objective is controlled within ±0.8%, indicating that the optical system of the microscope objective has relatively small distortion.

[0061] In the embodiment of the present application, the optical system of the microscope objective lens limits the Abbe number of the lens material and combines the first constraint condition and the second constraint condition, so that the optical system of the microscope objective lens uses a smaller number of lenses and has a large numerical aperture, high resolution, long working distance and can achieve chromatic aberration correction for the entire visible light band, while maintaining the characteristics of small field curvature and small distortion.

[0062] Embodiment 2:

[0063] An embodiment of the present application provides a microscope objective lens, including the optical system of the microscope objective lens described above, and the distortion of the microscope objective lens is controlled within -1% to 1%.

[0064] It should be noted that the content of the optical system of the microscope objective has been described in the first embodiment, and the content of the optical system of the microscope objective will not be repeated in this embodiment. In this embodiment, the microscope objective is arranged through the first lens group, the second lens group, and the third lens group, so that the first lens group has positive refractive power, the second lens group has positive refractive power, and the third lens group has positive or negative refractive power, and the long working distance of the microscope objective is guaranteed on the basis of a large numerical aperture. At the same time, by arranging the optical elements in the first lens group, the second lens group, and the third lens group, the microscope objective has a large aperture, high resolution, good imaging performance in a wide band, and good correction of chromatic aberration.

[0065] In the embodiment of the present application, the microscope objective lens limits the focal distance of the first lens group, the second lens group, and the third lens group, so that the microscope objective lens can achieve a longer working distance under the condition of a large numerical aperture, and use a smaller number of lenses, while preliminarily correcting spherical aberration, field curvature, and distortion. The microscope objective lens further corrects aberrations by limiting the intervals between the first lens group, the second lens group, and the third lens group. The microscope objective lens limits the Abbe number of the material of each optical element in the first lens group, the second lens group, and the third lens group to correct the chromatic aberration of the microscope objective lens in the full band of visible light. Thereby, the microscope objective lens can achieve a larger numerical aperture, a longer working distance, and chromatic aberration correction in the full band of visible light, while having the characteristics of good flat field, small distortion, and high resolution.

[0066] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0067] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0068] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0069] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0070] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An optical system of a microscope objective lens, characterized in that: The lens comprises a first lens group having positive refractive power, a second lens group having positive refractive power and a third lens group having positive or negative refractive power, which are arranged in sequence from the object side to the image side; The first lens group includes at least one or more optical elements with positive refractive power, the second lens group includes at least two or more optical elements with positive refractive power, and the Abbe number of the material of the optical elements is greater than a first threshold.

2. The optical system of the microscope objective according to claim 1, characterized in that: A ratio of a focal length of the first lens group to a focal length of the optical system is greater than a second threshold and less than a third threshold; a ratio of a focal length of the second lens group to a focal length of the optical system is greater than a fourth threshold and less than a fifth threshold; a ratio of a focal length of the third lens group to a focal length of the optical system is greater than a sixth threshold and less than a seventh threshold; a ratio of a length formed by the first lens group, the second lens group and the third lens group to a focal length of the optical system is greater than an eighth threshold and less than a ninth threshold.

3. The optical system of the microscope objective according to claim 2, characterized in that: The second threshold is 0.9, the third threshold is 1.2, the fourth threshold is 7.0, the fifth threshold is 15.0, the sixth threshold is -30, the seventh threshold is 40, the eighth threshold is 5.0, and the ninth threshold is 5.

8.

4. The optical system of the microscope objective lens according to claim 1, characterized in that: The ratio of the distance from the object side to the first lens group to the focal length of the optical system is less than a tenth threshold; the ratio of the distance from the first lens group to the second lens group to the focal length of the optical system is less than an eleventh threshold; and the ratio of the distance from the second lens group to the third lens group to the focal length of the optical system is less than a twelfth threshold.

5. The optical system of the microscope objective lens according to claim 4, characterized in that: The tenth threshold is 0.12, the eleventh threshold is 0.4, and the twelfth threshold is 0.

3.

6. The optical system of the microscope objective according to any one of claims 1 to 5, characterized in that: The first threshold is 70.

7. The optical system of the microscope objective according to any one of claims 1 to 5, characterized in that: The first lens group includes a first optical element with negative refractive power, a second optical element with positive refractive power and a third optical element with positive refractive power, which are arranged in sequence from the object side to the image side; and / or the second lens group includes a fourth optical element with positive refractive power and a fifth optical element with negative refractive power, which are arranged in sequence from the object side to the image side; and / or the third lens group includes a sixth optical element with negative refractive power and a seventh optical element with positive refractive power, which are arranged in sequence from the object side to the image side.

8. The optical system of the microscope objective according to claim 7, characterized in that: The first optical element is a lens or a first cemented lens, the second optical element is a lens, and the third optical element is a lens or a first cemented lens; and / or, the fourth optical element is a second cemented lens, and the fifth optical element is a first cemented lens; and / or, the sixth optical element is a first cemented lens, and the seventh optical element is a lens.

9. The optical system of the microscope objective lens according to claim 8, characterized in that: The first cemented lens is a cemented lens composed of two lenses; and / or the second cemented lens is a cemented lens composed of two or more lenses.

10. A microscope objective lens, characterized in that: An optical system comprising a microscope objective lens as claimed in any one of claims 1 to 9, wherein the distortion of the microscope objective lens is controlled within a range of -1% to 1%.

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