Microobjective and microscope
Through lens bonding technology, the complementary characteristics of different materials are used to solve the difficulties in chromatic aberration correction of traditional microscopes, the improvement of image quality and the simplification of system structure, and the service life of the lens is extended.
Patent Information
- Application Number
- CN202421174287.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-27
- Publication Date
- 2024-12-31
- Estimated Expiration
- 2034-05-27
AI Technical Summary
The traditional 100X multiplier microscope objective lens has difficulty in correcting the chromatic aberration of visible light bands due to the large numerical aperture, resulting in image distortion and inaccurate color.
The form of glued multiple lenses is adopted to reduce the color difference in the optical system and improve image quality by complementing the characteristics of different materials. The specific design includes glueing the second lens and the third lens, the fifth lens and the sixth lens, the seventh lens and the eighth lens, the ninth lens, the tenth lens, and the eleventh lens to form a negative and positive power. The lens group uses materials with different refractive indices and Abbe coefficients to compensate for each other's dispersion.
It effectively reduces chromatic aberration, improves image accuracy and clarity, simplifies the optical system structure, reduces reflected light energy loss, and extends the service life of the lens.
Smart Images
Figure CN222280945U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of optics, in particular to a microscope objective lens and a microscope. Background Art
[0002] The microscope is the most common tool for humans to explore the microscopic world, and the microscope objective is one of the most important optical devices that make up the microscope.
[0003] However, due to the large numerical aperture, the chromatic aberration correction of the entire visible light band is difficult for traditional 100X microscope objectives, and the imaging process is often affected by chromatic aberration, including axial chromatic aberration and vertical chromatic aberration, which is caused by the difference in refractive index when light passes through substances of different wavelengths, resulting in color fringes on the edge of the image, inaccurate colors, and reduced optical system performance. Traditional microscope objectives are greatly affected by chromatic aberration, resulting in image distortion, inaccurate colors, and other problems, affecting the effect of observation and analysis. Utility Model Content
[0004] The main purpose of the utility model is to provide a microscope objective lens and a microscope, and in particular to a microscope for solving the problem that a traditional microscope objective lens is greatly affected by chromatic aberration, resulting in image distortion and inaccurate color.
[0005] To achieve the above-mentioned purpose, the present invention provides a microscope objective lens, which has an object side and an image side correspondingly arranged along the optical axis direction, and comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side;
[0006] Among them, the first lens has negative optical power, the second lens and the third lens are glued to form a first lens group, the first lens group has negative optical power, the fourth lens has positive optical power, the fifth lens and the sixth lens are glued to form a second lens group, the second lens group has positive optical power, the seventh lens and the eighth lens are glued to form a third lens group, the third lens group has negative optical power, the ninth lens, the tenth lens, and the eleventh lens are glued in sequence to form a fourth lens group, the fourth lens group has positive optical power, the twelfth lens has positive optical power, and the thirteenth lens has positive optical power.
[0007] In one embodiment, the thickness of the first lens is A1, the radius of curvature close to the object side is R11, and the radius of curvature close to the image side is R12; the thickness of the fourth lens is A4, the radius of curvature close to the object side is R41, and the radius of curvature close to the image side is R42;
[0008] Among them, 4mm≤A1≤6mm, 9mm≤R11≤13mm, 2mm≤R12≤4mm; 5mm≤A4≤7mm, -135mm≤R41≤-120mm; -20mm≤R42≤-10mm, so that the lens field curvature of the microscope objective lens is set to be less than 2μm.
[0009] In one embodiment, the total length of the microscope objective is L, 50mm≤L≤60mm, and the distance from the center of the image side surface of the thirteenth lens to the imaging surface of the microscope objective on the optical axis is l, 2.5mm≤l≤2.7mm.
[0010] In one embodiment, the object side numerical aperture of the microscope objective is NA, 0.5≤NA≤0.6.
[0011] In one embodiment, the focal length of the first lens is f1, -6mm≤f1≤-5mm;
[0012] The focal length of the second lens is f2, -7mm≤f2≤-6mm;
[0013] The focal length of the third lens is f3, 13mm≤f3≤15mm;
[0014] The focal length of the fourth lens is f4, 36mm≤f4≤40mm;
[0015] The focal length of the fifth lens is f5, -21mm≤f5≤-20mm;
[0016] The focal length of the sixth lens is f6, 17mm≤f6≤19mm;
[0017] The focal length of the seventh lens is f7, 18mm≤f7≤20mm;
[0018] The focal length of the eighth lens is f8, -17mm≤f8≤-15mm;
[0019] The focal length of the ninth lens is f9, 14mm≤f9≤16mm;
[0020] The focal length of the tenth lens is f10, -10mm≤f10≤-9mm;
[0021] The focal length of the eleventh lens is f11, 11mm≤f11≤13mm;
[0022] The focal length of the twelfth lens is f12, 22mm≤f12≤24mm;
[0023] The focal length of the thirteenth lens is f13, 15mm≤f13≤16mm;
[0024] So that the focal length F of the microscope objective lens satisfies: 1.95mm≤F≤2.05mm.
[0025] In one embodiment, the refractive index of the second lens is 1.4≤N2≤1.5;
[0026] The refractive index of the third lens is 1.9≤N3≤2.0;
[0027] The refractive index of the fifth lens is 1.9≤N5≤2.0;
[0028] The refractive index of the sixth lens is 1.4≤N6≤1.5;
[0029] The refractive index of the seventh lens is 1.5≤N7≤1.6;
[0030] The refractive index of the eighth lens is 1.7≤N8≤1.8;
[0031] The refractive index of the ninth lens is 1.4≤N9≤1.5;
[0032] The refractive index of the tenth lens is 1.4≤N10≤1.5;
[0033] The refractive index of the eleventh lens is 1.4≤N11≤1.5.
[0034] In one embodiment, the image-side ray telecentricity of the microscope objective is α, -0.1°≤α≤+0.1°.
[0035] In one embodiment, the microscope objective further includes an aperture stop, which is disposed on the optical axis and located between the sixth lens and the seventh lens.
[0036] In one embodiment, the first lens to the thirteenth lens sequentially arranged from the object side to the image side are all configured as one of a flint lens, a glass lens, and a flint and glass hybrid lens.
[0037] The utility model also provides a microscope, the microscope comprising a microscope objective lens, the microscope objective lens having an object side and an image side correspondingly arranged along an optical axis direction, the microscope objective lens comprising a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side;
[0038] Among them, the first lens has negative optical power, the second lens and the third lens are glued to form a first lens group, the first lens group has negative optical power, the fourth lens has positive optical power, the fifth lens and the sixth lens are glued to form a second lens group, the second lens group has positive optical power, the seventh lens and the eighth lens are glued to form a third lens group, the third lens group has negative optical power, the ninth lens, the tenth lens, and the eleventh lens are glued in sequence to form a fourth lens group, the fourth lens group has positive optical power, the twelfth lens has positive optical power, and the thirteenth lens has positive optical power.
[0039] The technical solution of the utility model achieves the effect of improving chromatic aberration by adopting the form of gluing two or more lenses and the cooperation between multiple lenses and lens groups. The second lens 2 and the third lens 3 are glued; the fifth lens 5 and the sixth lens 6 are glued; the seventh lens 7 and the eighth lens 8 are glued; and the ninth lens 9, the tenth lens 10, and the eleventh lens 11 are glued in sequence. The main purpose of this design is to reduce the chromatic aberration in the optical system and improve the image quality by complementing the characteristics of different materials. Chromatic aberration is caused by the different propagation speeds of light of different wavelengths in the same medium, which causes light of different colors to not converge at the same focus at the same time, forming color fringes and thus reducing the image quality. The glued lens uses a combination of positive and negative lenses of two or more materials with different refractive indices and Abbe coefficients, so that the glued lens can compensate for the dispersion of each other, thereby reducing the chromatic aberration as a whole. In general, the reason why the glued lens can reduce chromatic aberration is that its unique structure and material selection allow light of different wavelengths to be properly processed at different levels, thereby achieving overall chromatic aberration correction. In addition, multiple lenses can be combined into a composite lens by gluing, which can simplify the structure of the optical system, reduce the loss of reflected light energy, and thus improve the image quality and clarity. The gluing between lenses can simplify the processing of complex lenses, reduce the processing steps, and save time and cost. The gluing between lenses can also protect the lenses from external physical damage and extend their service life. BRIEF DESCRIPTION OF THE DRAWINGS
[0040] In order to more clearly illustrate the embodiments of the utility model 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 utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0041] Figure 1 A schematic plan view of an embodiment of a microscope objective lens provided by the utility model;
[0042] Figure 2 for Figure 1 MTF curve of the microscope objective lens;
[0043] Figure 3 for Figure 1 Axial chromatic aberration curve of the microscope objective;
[0044] Figure 4 for Figure 1 Vertical axis chromatic aberration curve of the microscope objective;
[0045] Figure 5 for Figure 1 Plot of the field curvature of a microscope objective.
[0046] Description of Figure Numbers:
[0047] 100. Microscope objective lens; 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens; 8. Eighth lens; 9. Ninth lens; 10. Tenth lens; 11. Eleventh lens; 12. Twelfth lens; 13. Thirteenth lens; 14. Stop; 15. First lens group; 16. Second lens group; 17. Third lens group; 18. Fourth lens group.
[0048] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION
[0049] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.
[0050] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indications will also change accordingly.
[0051] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the utility model.
[0052] The traditional 100X microscope objective lens has a large numerical aperture, and it is difficult to correct the chromatic aberration in the entire visible light band. The imaging process is often affected by chromatic aberration, including axial chromatic aberration and vertical chromatic aberration, which is caused by the difference in refractive index when light passes through materials of different wavelengths, resulting in image distortion, inaccurate colors and other problems. The traditional microscope objective lens is greatly affected by chromatic aberration, resulting in image distortion, inaccurate colors and other problems, affecting the effect of observation and analysis.
[0053] The utility model provides a microscope objective lens.
[0054] See also Figure 1 In one embodiment of the utility model, the microscope objective lens 100 has an object side and an image side correspondingly arranged along the optical axis direction, and the microscope objective lens 100 includes a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, an eleventh lens 11, a twelfth lens 12, and a thirteenth lens 13 arranged in sequence from the object side to the image side;
[0055] Among them, the first lens 1 has negative optical power, the second lens 2 and the third lens 3 are glued to form a first lens group 15, the first lens group 15 has negative optical power, the fourth lens 4 has positive optical power, the fifth lens 5 and the sixth lens 6 are glued to form a second lens group 16, the second lens group 16 has positive optical power, the seventh lens 7 and the eighth lens 8 are glued to form a third lens group 17, the third lens group 17 has negative optical power, the ninth lens 9, the tenth lens 10, and the eleventh lens 11 are glued in sequence to form a fourth lens group 18, the fourth lens group 18 has positive optical power, the twelfth lens 12 has positive optical power, and the thirteenth lens 13 has positive optical power.
[0056] The technical solution of the utility model achieves the effect of improving chromatic aberration by adopting the form of gluing two or more lenses and the cooperation between multiple lenses and lens groups. The second lens 2 and the third lens 3 are glued; the fifth lens 5 and the sixth lens 6 are glued; the seventh lens 7 and the eighth lens 8 are glued; and the ninth lens 9, the tenth lens 10, and the eleventh lens 11 are glued in sequence. The main purpose of this design is to reduce the chromatic aberration in the optical system and improve the image quality by complementing the characteristics of different materials. Chromatic aberration is caused by the different propagation speeds of light of different wavelengths in the same medium, which causes light of different colors to not converge at the same focus at the same time, forming a blurred image. The glued lens uses two or more materials with different refractive indices, so that each material can better transmit light of a specific wavelength, thereby reducing the chromatic aberration as a whole. In addition, the materials of each layer of the glued lens can also be specifically designed and selected to produce a phase difference at the interface between them, further helping to offset the chromatic aberration. This method is called "cascade chromatic aberration correction", which can effectively improve the imaging quality of the optical system. In general, the reason why cemented lenses can reduce chromatic aberration is that their unique structure and material selection allow different wavelengths of light to be properly processed at different levels, thus achieving overall chromatic aberration correction. In addition, by cementing, multiple lenses can be combined into a composite lens, which can simplify the structure of the optical system and reduce the loss of reflected light energy, thereby improving the image quality and clarity. Gluing between lenses can simplify the processing of complex lenses, reduce processing steps, and save time and cost. Gluing between lenses can also protect the lenses from external physical damage and extend their service life.
[0057] The main purpose of the multiple lens bonding design is to reduce the chromatic aberration in the optical system and improve the image quality by complementing the properties of different materials. In this scheme, the preferred parameters of each lens are as follows:
[0058]
[0059]
[0060] Field curvature occurs in microscopes. Field curvature refers to the phenomenon that when a planar object passes through a lens system, the image plane after all planar object points are focused does not coincide with the ideal image plane, but is imaged as a curved image plane. Field curvature can cause the clarity of the image to gradually change, and even blur in some areas. In order to solve this problem, the shape of the lens is designed to directly affect the propagation path of light, thereby affecting the size and shape of the field curvature. In addition, by adjusting the shape of the lens, the propagation path of the light beam can be changed, thereby optimizing the imaging quality and improving the imaging clarity and accuracy. Since different optical systems have different requirements for field curvature, by adjusting the shape of the lens, different optical design requirements can be met to achieve better optical performance. For the microscope objective 100 in the utility model, the field curvature is required to be less than 2μm. This embodiment mainly designs the appearance of the first lens 1 and the fourth lens 4 to achieve the purpose of improving the field curvature. The thickness of the first lens 1 is A1, the radius of curvature close to the object side is R11, and the radius of curvature close to the image side is R12; the thickness of the fourth lens 4 is A4, the radius of curvature close to the object side is R41, and the radius of curvature close to the image side is R42; wherein, 4mm≤A1≤6mm, 9mm≤R11≤13mm, 2mm≤R12≤4mm; 5mm≤A4≤7mm, -135mm≤R41≤-120mm; -20mm≤R42≤-10mm, so that the field curvature of the microscope objective 100 is set to be less than 2μm.
[0061] The practical new design of the microscope objective lens 100 needs to satisfy the following conditions: the total length of the microscope objective lens 100 is L, 50mm≤L≤60mm; the distance from the center of the image side surface of the thirteenth lens 13 to the imaging surface of the microscope objective lens 100 on the optical axis is l, 2.5mm≤l≤2.7mm. That is, the working distance of the microscope objective lens 100 must be greater than or equal to 2.5mm.
[0062] The size of the object numerical aperture NA directly affects the performance of the optical system. Specifically, the larger the object numerical aperture NA, the wider the range of light that the lens can receive, thereby improving the resolution of the optical system and allowing us to see more subtle structures. At the same time, the object numerical aperture NA will also affect the focal depth of the optical system, that is, the distance range at which the lens can clearly image. Generally speaking, the larger the object numerical aperture NA, the shallower the focal depth. In the use of a microscope, the size of the object numerical aperture NA directly determines the resolution and field of view of the microscope. In addition, the object numerical aperture NA is also related to the magnification. The larger the object numerical aperture NA, the higher the magnification, but the corresponding field of view width will decrease. In one embodiment, the object numerical aperture of the microscope objective 100 is NA, 0.5≤NA≤0.6. The image-side effective field of view of the microscope objective 100 in this embodiment is φ0.16mm, the object numerical aperture can reach 0.55, and the theoretical limit resolution can reach 0.4μm.
[0063] The utility model requires a microscope objective lens 100 with a magnification of 100 times, and the focal length F of the corresponding microscope objective lens 100 needs to satisfy: 1.95mm≤F≤2.05mm. The focal length is preferably 2mm. Among them, the focal lengths of the lenses need to satisfy the following corresponding requirements: the focal length of the first lens 1 is f1, -6mm≤f1≤-5mm; the focal length of the second lens 2 is f2, -7mm≤f2≤-6mm; the focal length of the third lens 3 is f3, 13mm≤f3≤15mm; the focal length of the fourth lens 4 is f4, 36mm≤f4≤40mm; the focal length of the fifth lens 5 is f5, -21mm≤f5≤-20mm; the focal length of the sixth lens 6 is f6, 17mm≤f6≤19mm; the focal length of the seventh lens 7 is f7, 18mm≤f7≤20mm; the focal length of the eighth lens 8 is f9, 18mm≤f9≤20mm; the focal length of the eighth lens 9 is f10, 16mm≤f11≤20mm; the focal length of the eighth lens 10 is f11, 16mm≤f12≤20mm; the focal length of the eighth lens 10 is f12, 16mm≤f13≤20mm; the focal length of the eighth lens 10 is f13, 16mm≤f14≤20mm; the focal length of the eighth lens 10 is f14, 16mm≤f15≤20mm; the focal length of the eighth lens 10 is f15, 16mm≤f16≤20mm; the focal length of the eighth lens 10 is f16, 16mm≤f16≤20mm; the focal length of the eighth lens 10 is f17, 18mm≤f17≤20mm; the focal length of The focal length of the ninth lens 9 is f8, -17mm≤f8≤-15mm; the focal length of the ninth lens 9 is f9, 14mm≤f9≤16mm; the focal length of the tenth lens 10 is f10, -10mm≤f10≤-9mm; the focal length of the eleventh lens 11 is f11, 11mm≤f11≤13mm; the focal length of the twelfth lens 12 is f12, 22mm≤f12≤24mm; the focal length of the thirteenth lens 13 is f13, 15mm≤f13≤16mm; so that the focal length F of the microscope objective lens 100 satisfies: 1.95mm≤F≤2.05mm.
[0064] In an optical system, the refractive index can be used to selectively control light of a specific wavelength band. A material with a specific refractive index can be selected so that the material has a higher transmittance for light of certain wavelengths and a higher reflectance for light of other wavelengths. In this way, selective transmission of light of a specific wavelength band can be achieved. The design wavelength of the microscope objective lens 100 designed in the utility model is 435nm-655nm. In addition, the refractive index of the lens is one of the important factors that determine the size of its chromatic aberration. Chromatic aberration is caused by the fact that light of different wavelengths has different refractive indices when passing through the lens, resulting in light of different colors being unable to converge at the same focus at the same time, thereby forming chromatic aberration. In order to improve chromatic aberration, a suitable refractive index is selected, and a lens material with lower dispersion is selected, because the refractive index of these materials changes less with wavelength, thereby reducing chromatic aberration. In one embodiment, the refractive index of each lens satisfies: the refractive index of the second lens 2 is 1.4≤N2≤1.5; the refractive index of the third lens 3 is 1.9≤N3≤2.0; the refractive index of the fifth lens 5 is 1.9≤N5≤2.0; the refractive index of the sixth lens 6 is 1.4≤N6≤1.5; the refractive index of the seventh lens 7 is 1.5≤N7≤1.6; the refractive index of the eighth lens 8 is 1.7≤N8≤1.8; the refractive index of the ninth lens 9 is 1.4≤N9≤1.5; the refractive index of the tenth lens 10 is 1.4≤N10≤1.5; and the refractive index of the eleventh lens 11 is 1.4≤N11≤1.5.
[0065] In order to improve the imaging quality, in one embodiment, the telecentricity of the image-side light of the microscope objective lens 100 is α, -0.1°≤α≤+0.1°. Telecentricity refers to a characteristic of the microscope objective lens 100, which relates to the relationship between the imaging light and the optical axis. Specifically, the microscope objective lens 100 with high telecentricity can make the imaging light closer to parallel to the optical axis, which can reduce the perspective distortion and shadow effect during imaging. The microscope objective lens 100 with high telecentricity can provide highly uniform illumination and optimized imaging quality, which is very helpful for the needs of precise measurement and analysis. The microscope objective lens 100 with high telecentricity can reduce optical distortion, making the imaging more realistic and accurate, which is particularly important for application scenarios that require high-precision measurement. The microscope objective lens 100 with high telecentricity usually has a higher resolution and can capture subtle image details, which is very important for defect detection and precision measurement. The microscope objective lens 100 with high telecentricity can provide a larger depth of field range, so that objects within a certain distance can be clearly imaged, which helps to simplify system design and improve imaging flexibility.
[0066] In order to improve the resolution and imaging clarity of the microscope objective lens 100, in one embodiment, the microscope objective lens 100 further includes an aperture 14, which is disposed on the optical axis and between the sixth lens 6 and the seventh lens 7. The influence of the aperture 14 on the microscope objective lens 100 is mainly reflected in the following aspects: it affects the object-side numerical aperture of the microscope objective lens 100, thereby affecting its resolution and imaging quality; it affects the imaging brightness of the microscope. If the aperture 14 is too large, the brightness may be reduced, and if the aperture 14 is too small, the brightness may be too high. The imaging clarity of the microscope is affected, and the position and size of the aperture 14 will have an impact on it. Therefore, the use of the aperture 14 is crucial to improving the imaging quality and resolution of the microscope.
[0067] Taking into account the cost, ease of obtaining, and refractive index of the material, in one embodiment, the first lens 1 to the thirteenth lens 13 arranged sequentially from the object side to the image side are all configured as one of a flint lens, a glass lens, and a flint and glass hybrid lens.
[0068] The utility model also provides a microscope, the microscope comprising a microscope objective lens 100, the microscope objective lens 100 having an object side and an image side correspondingly arranged along an optical axis direction, the microscope objective lens 100 comprising a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9, a tenth lens 10, an eleventh lens 11, a twelfth lens 12, and a thirteenth lens 13 arranged in sequence from the object side to the image side;
[0069] Among them, the first lens 1 has negative optical power, the second lens 2 and the third lens 3 are glued to form a first lens group 15, the first lens group 15 has negative optical power, the fourth lens 4 has positive optical power, the fifth lens 5 and the sixth lens 6 are glued to form a second lens group 16, the second lens group 16 has positive optical power, the seventh lens 7 and the eighth lens 8 are glued to form a third lens group 17, the third lens group 17 has negative optical power, the ninth lens 9, the tenth lens 10, and the eleventh lens 11 are glued in sequence to form a fourth lens group 18, the fourth lens group 18 has positive optical power, the twelfth lens 12 has positive optical power, and the thirteenth lens 13 has positive optical power.
[0070] The utility model also provides a microscope, which includes a microscope objective lens. The specific structure of the microscope objective lens refers to the above embodiments. Since the microscope adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.
[0071] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A microscope objective lens, characterized in that: The microscope objective lens has an object side and an image side correspondingly arranged along the optical axis direction, and the microscope objective lens includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, a twelfth lens, and a thirteenth lens arranged in sequence from the object side to the image side; Among them, the first lens has negative optical power, the second lens and the third lens are glued to form a first lens group, the first lens group has negative optical power, the fourth lens has positive optical power, the fifth lens and the sixth lens are glued to form a second lens group, the second lens group has positive optical power, the seventh lens and the eighth lens are glued to form a third lens group, the third lens group has negative optical power, the ninth lens, the tenth lens, and the eleventh lens are glued in sequence to form a fourth lens group, the fourth lens group has positive optical power, the twelfth lens has positive optical power, and the thirteenth lens has positive optical power.
2. The microscope objective lens according to claim 1, characterized in that The thickness of the first lens is A1, the radius of curvature close to the object side is R11, and the radius of curvature close to the image side is R12; the thickness of the fourth lens is A4, the radius of curvature close to the object side is R41, and the radius of curvature close to the image side is R42; Among them, 4mm≤A1≤6mm, 9mm≤R11≤13mm, 2mm≤R12≤4mm; 5mm≤A4≤7mm, -135mm≤R41≤-120mm; -20mm≤R42≤-10mm, so that the lens field curvature of the microscope objective lens is set to be less than 2μm.
3. The microscope objective lens according to claim 1, characterized in that The total length of the microscope objective lens is L, 50mm≤L≤60mm, and the distance from the center of the image side surface of the thirteenth lens to the imaging surface of the microscope objective lens on the optical axis is l, 2.5mm≤l≤2.7mm.
4. The microscope objective lens according to claim 1, characterized in that The object side numerical aperture of the microscope objective lens is NA, 0.5≤NA≤0.
6.
5. The microscope objective lens according to claim 1, characterized in that The focal length of the first lens is f1, -6mm≤f1≤-5mm; The focal length of the second lens is f2, -7mm≤f2≤-6mm; The focal length of the third lens is f3, 13mm≤f3≤15mm; The focal length of the fourth lens is f4, 36mm≤f4≤40mm; The focal length of the fifth lens is f5, -21mm≤f5≤-20mm; The focal length of the sixth lens is f6, 17mm≤f6≤19mm; The focal length of the seventh lens is f7, 18mm≤f7≤20mm; The focal length of the eighth lens is f8, -17mm≤f8≤-15mm; The focal length of the ninth lens is f9, 14mm≤f9≤16mm; The focal length of the tenth lens is f10, -10mm≤f10≤-9mm; The focal length of the eleventh lens is f11, 11mm≤f11≤13mm; The focal length of the twelfth lens is f12, 22mm≤f12≤24mm; The focal length of the thirteenth lens is f13, 15mm≤f13≤16mm; So that the focal length F of the microscope objective lens satisfies: 1.95mm≤F≤2.05mm.
6. The microscope objective lens according to claim 1, characterized in that The refractive index of the second lens is 1.4≤N2≤1.5; The refractive index of the third lens is 1.9≤N3≤2.0; The refractive index of the fifth lens is 1.9≤N5≤2.0; The refractive index of the sixth lens is 1.4≤N6≤1.5; The refractive index of the seventh lens is 1.5≤N7≤1.6; The refractive index of the eighth lens is 1.7≤N8≤1.8; The refractive index of the ninth lens is 1.4≤N9≤1.5; The refractive index of the tenth lens is 1.4≤N10≤1.5; The refractive index of the eleventh lens is 1.4≤N11≤1.
5.
7. The microscope objective lens according to claim 1, characterized in that The image-side light telecentricity of the microscope objective is α, -0.1°≤α≤+0.1°.
8. The microscope objective lens according to claim 1, characterized in that The microscope objective lens further includes an aperture, which is arranged on the optical axis and located between the sixth lens and the seventh lens.
9. The microscope objective lens according to claim 1, characterized in that: The first lens to the thirteenth lens arranged in sequence from the object side to the image side are all configured as one of a flint lens, a glass lens, and a flint and glass hybrid lens.
10. A microscope, characterized in that: The invention comprises a microscope objective lens as claimed in any one of claims 1 to 9.