Microobjective and microscopic imaging system

Abstract

The invention provides a microscope objective and a microscopic imaging system, and relates to the technical field of microscope lenses. The microscope objective comprises a first lens with positive focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, a seventh lens with negative focal power and an eighth lens with positive focal power which are sequentially arranged from an object side to an image side, the microscope objective lens comprises a ninth lens with positive focal power, a tenth lens with negative focal power, an eleventh lens with positive focal power, a twelfth lens with positive focal power, a thirteenth lens with positive focal power and an image plane, so that the numerical aperture of the microscope objective lens under ten-time magnification reaches 0.33, and the working distance of the microscope objective lens reaches 34 mm; wherein all the lenses are spherical lenses. According to the scheme, the microscope objective with low cost, high numerical aperture and long working distance is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microscope objective, in particular to a microscope objective and a microscopic imaging system. BACKGROUND

[0002] In recent years, with the growing demand for high-precision microscopic imaging in the fields of scientific research, industrial detection and biomedical, the technology of microscope objective has been rapidly developed. In the optical system of a microscope, the objective is the core component, and its performance directly determines the imaging quality, resolution and practicability.

[0003] High numerical aperture objectives are widely used in the fields of biological research and semiconductor detection. Higher NA can provide higher resolution and stronger light collection capability, which is suitable for observing microstructures. Long working distance objectives are also widely used in industrial detection, especially in cases where the sample surface shielding or protective cover needs to be avoided. Such objectives usually sacrifice the numerical aperture to obtain a longer working distance, resulting in relatively low resolution and imaging quality. In order to balance the long working distance and high-quality imaging, traditional designs often rely on more high-precision aspherical elements or high refractive index low dispersion materials, resulting in a significant increase in manufacturing cost, which is difficult to meet the batch demand of the low-cost market.

[0004] Therefore, there is an urgent need in the market for a microscope objective that can have low cost, high numerical aperture and long working distance. SUMMARY

[0005] The main purpose of the present application is to provide a microscope objective and a microscopic imaging system, which can have low cost, high numerical aperture and long working distance.

[0006] To achieve the above purpose, the present application provides a microscope objective, which has an object side and an image side arranged oppositely along the optical axis direction, and comprises, in order from the object side to the image side, a first lens with positive focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, a seventh lens with negative focal power, an eighth lens with positive focal power, a ninth lens with positive focal power, a tenth lens with negative focal power, an eleventh lens with positive focal power, a twelfth lens with positive focal power, a thirteenth lens with positive focal power and an image surface, so that the numerical aperture of the microscope objective reaches 0.33 at a ten-fold magnification, and the working distance of the microscope objective reaches 34mm.

[0007] Among them, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the twelfth lens and the thirteenth lens are all arranged as spherical lenses.

[0008] In an embodiment, the microscope objective further comprises a diaphragm, which is arranged between the fourth lens and the fifth lens.

[0009] In an embodiment, the fifth lens and the sixth lens are cemented together, and the focal power of the cemented lens formed after the cementing of the fifth lens and the sixth lens is positive; and / or,

[0010] the seventh lens and the eighth lens are cemented together, and the focal power of the cemented lens formed after the cementing of the seventh lens and the eighth lens is negative; and / or,

[0011] the ninth lens, the tenth lens and the eleventh lens are cemented together, and the focal power of the cemented lens formed after the cementing of the ninth lens, the tenth lens and the eleventh lens is positive.

[0012] In an embodiment, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the focal length of the eighth lens is f8, the focal length of the ninth lens is f9, the focal length of the tenth lens is f10, the focal length of the eleventh lens is f11, the focal length of the twelfth lens is f12, and the focal length of the thirteenth lens is f13, wherein:

[0013] 62mm < f1 < 60mm, -33mm < f2 < -30, -25mm < f3 < -20mm, 60mm < f4 < 65mm, 35mm < f5 < 38mm, -76mm < f6 < -75mm, -51mm < f7 < -50mm, 60mm < f8 < 65mm, 78mm < f9 < 80mm, -36mm < f10 < -35mm, 55mm < f11 < 60mm, 68mm < f12 < 70mm, 95mm < f13 < 100mm.

[0014] In an embodiment, the materials of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the twelfth lens and the thirteenth lens are all set to be Schott glass.

[0015] In an embodiment, the first lens is a double convex lens;

[0016] the second lens is a double concave lens;

[0017] the third lens is a double concave lens;

[0018] The fourth lens is a meniscus lens, and the object side surface thereof is a concave surface;

[0019] The fifth lens is a biconvex lens;

[0020] The sixth lens is a meniscus lens, and the object side surface thereof is a concave surface;

[0021] The seventh lens is a biconcave lens;

[0022] The eighth lens is a biconvex lens;

[0023] The ninth lens is a biconvex lens;

[0024] The tenth lens is a biconcave lens;

[0025] The eleventh lens is a biconvex lens;

[0026] The twelfth lens is a biconvex lens;

[0027] The thirteenth lens is a meniscus lens, and the object side surface thereof is a convex surface.

[0028] In an embodiment, the diameter of the effective field of view on the image side of the microscope objective is φ, and φ≤2.26mm is satisfied.

[0029] In an embodiment, the chief ray wavelength of the microscope objective on the image side is A, and -0.05°≤A≤0.05° is satisfied.

[0030] The present application also provides a microscope imaging system, which comprises the microscope objective described above, and the microscope objective has an object side and an image side arranged oppositely along the optical axis direction, and comprises, from the object side to the image side, a first lens with positive focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, a seventh lens with negative focal power, an eighth lens with positive focal power, a ninth lens with positive focal power, a tenth lens with negative focal power, an eleventh lens with positive focal power, a twelfth lens with positive focal power, a thirteenth lens with positive focal power, and an image surface, so that the numerical aperture of the microscope objective reaches 0.33 at a ten-fold magnification, and the working distance of the microscope objective reaches 34mm.

[0031] The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the twelfth lens, and the thirteenth lens are all arranged as spherical lenses.

[0032] The technical scheme provided by the present application has the advantages that the first lens with negative focal length is arranged to facilitate the collection of light rays of the optical system and effectively increase the field of view; the thirteenth lens with positive focal length is arranged to bear a large focal length of the system, change the propagation direction of the light beam, correct the aberration of the off-axis field of view, and more facilitate the imaging of the light beam on the image plane; all the lenses are arranged as spherical lenses to reduce the cost and facilitate subsequent assembly; the thirteen lenses are adopted, and the focal lengths and shape matching relationships of the lenses are reasonably arranged to ensure the imaging quality of the lens. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained according to the structures shown in the drawings without creative labor.

[0034] Figure 1 The structure schematic diagram of an embodiment of the microscope objective provided by the present application is shown in the figure.

[0035] Figure 2 The MTF curve schematic diagram of the microscope objective in the embodiment is shown in the figure. Figure 1

[0036] The axial chromatic aberration curve schematic diagram of the microscope objective in the embodiment is shown in the figure. Figure 3 Figure 1 The off-axis chromatic aberration curve schematic diagram of the microscope objective in the embodiment is shown in the figure.

[0037] Figure 4 Figure 1 The image field curvature curve schematic diagram of the microscope objective in the embodiment is shown in the figure.

[0038] Figure 5 The image field curvature curve schematic diagram of the microscope objective in the embodiment is shown in the figure. Figure 1

[0039] Explanation of reference numerals:

[0040] 1000, microscope objective; 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, diaphragm.

[0041] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the drawings.​​​ DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0043] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture, and if the certain posture changes, the directional indications also change accordingly.

[0044] In addition, if the embodiments of the present application involve descriptions such as "first", "second", etc., the descriptions of "first", "second", etc. are only for description purposes, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first" and "second" can explicitly or implicitly include at least one of the features. In addition, "and / or" or "and / or" appearing throughout the text means that the three parallel schemes include A scheme, or B scheme, or A and B schemes are satisfied at the same time. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person of ordinary skill in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the protection scope claimed by the present application.

[0045] In recent years, with the growing demand for high-precision microscopic imaging in the fields of scientific research, industrial detection and biomedical science, the technology of microscopic objective lens has developed rapidly. In the optical system of a microscope, the objective lens is the core component, and its performance directly determines the imaging quality, resolution and practicability.

[0046] High numerical aperture objective lenses are widely used in the fields of biological research and semiconductor detection. Higher NA can provide higher resolution and stronger light collection capability, which is suitable for observing microstructures. Long working distance objective lenses have also been widely used in industrial detection, especially in cases where it is necessary to avoid sample surface obstructions or protective covers. Such objective lenses usually sacrifice the numerical aperture to achieve a longer working distance, resulting in relatively low resolution and imaging quality. In order to balance the long working distance and high-quality imaging, traditional designs often rely on more high-precision aspherical elements or high refractive index low dispersion materials, resulting in a significant increase in manufacturing cost, making it difficult to meet the batch demand of the low-cost market.

[0047] Therefore, there is an urgent need in the market for a microscope objective that can have low cost, high numerical aperture and long working distance.

[0048] The main purpose of the present application is to provide a microscope objective and a microscopic imaging system, aiming to provide a microscope objective that can have low cost, high numerical aperture and long working distance.

[0049] Please refer to Figure 1 The present application provides a microscope objective 1000, which has an object side and an image side arranged oppositely along the optical axis direction, and comprises, arranged in order from the object side to the image side, a first lens 1 with positive focal power, a second lens 2 with negative focal power, a third lens 3 with negative focal power, a fourth lens 4 with positive focal power, a fifth lens 5 with positive focal power, a sixth lens 6 with negative focal power, a seventh lens 7 with negative focal power, an eighth lens 8 with positive focal power, a ninth lens 9 with positive focal power, a tenth lens 10 with negative focal power, an eleventh lens 11 with positive focal power, a twelfth lens 12 with positive focal power, a thirteenth lens 13 with positive focal power, and an image plane, so that the numerical aperture of the microscope objective 1000 under ten times magnification reaches 0.33, and the working distance of the microscope objective 1000 reaches 34mm; wherein the first lens 1, the second lens, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, the eighth lens, the ninth lens 9, the tenth lens 10, the eleventh lens 11, the twelfth lens 12 and the thirteenth lens 13 are all arranged as spherical lenses.

[0050] The technical scheme provided by the present application has the advantages that by arranging the first lens 1 with negative focal power, the collection of light rays in the optical system is facilitated, and the field of view range can be effectively increased; by arranging the thirteenth lens 13 with positive focal power, a large focal power of the system is borne, the propagation direction of the light beam is changed, the aberration of the off-axis field of view is corrected, and the imaging of the light beam on the image plane is more facilitated; by arranging all the above-mentioned lenses as spherical lenses, the cost is reduced, and subsequent assembly is facilitated; by adopting thirteen lenses and reasonably arranging the focal power and shape matching relationship of each lens, the imaging quality of the lens is ensured. The numerical aperture of the lens under ten times magnification can reach 0.33, and the working distance can reach 34mm, so that the advantages of high numerical aperture and long working distance are combined.

[0051] Further, the microscope objective 1000 further comprises a diaphragm 14, which is arranged between the fourth lens 4 and the fifth lens 5. The diaphragm 14 limits the beam aperture on the optical axis, blocks part of the light, thereby reducing the spot, improving the image contrast, and also enlarges the target surface and improves the image quality. According to the actual situation, the light flux of the diaphragm 7 is adjusted, which is helpful to further improve the imaging quality.

[0052] Further, in order to improve the image quality of the optical system, reduce the loss of optical energy, increase the imaging clarity, protect the scale surface, and further optimize the processing flow to meet the design requirements, in an embodiment, the fifth lens 5 and the sixth lens 6 are glued together, and the optical power of the glued lens formed after the fifth lens 5 and the sixth lens 6 are glued together is positive.

[0053] In another embodiment, the seventh lens 7 and the eighth lens 8 are glued together, and the optical power of the glued lens formed after the seventh lens 7 and the eighth lens 8 are glued together is negative.

[0054] In still another embodiment, the ninth lens 9, the tenth lens 10, and the eleventh lens 11 are glued together, and the optical power of the glued lens formed after the ninth lens 9, the tenth lens 10, and the eleventh lens 11 are glued together is positive.

[0055] In this way, by reasonably using the glued parts and reasonably distributing the optical power, the aberration is well corrected, and the axial chromatic aberration and the magnification chromatic aberration in the visible light waveband range are effectively reduced, and the imaging quality is improved.

[0056] It is worth mentioning that the above three embodiments can be set up alternatively or simultaneously, and the preferred embodiment of the present scheme adopts the scheme of simultaneous setting, which has better effect.

[0057] Further, the focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the focal length of the eighth lens is f8, the focal length of the ninth lens is f9, the focal length of the tenth lens is f10, the focal length of the eleventh lens is f11, the focal length of the twelfth lens is f12, and the focal length of the thirteenth lens is f13, wherein: 62mm < f1 < 60mm, -33mm < f2 < -30, -25mm < f3 < -20mm, 60mm < f4 < 65mm, 35mm < f5 < 38mm, -76mm < f6 < -75mm, -51mm < f7 < -50mm, 60mm < f8 < 65mm, 78mm < f9 < 80mm, -36mm < f10 < -35mm, 55mm < f11 < 60mm, 68mm < f12 < 70mm, and 95mm < f13 < 100mm. This embodiment is a preferred embodiment, and the mutual combination of different lenses and the reasonable allocation of the optical power thereof enable the entire optical system to have a higher imaging quality.

[0058] Specifically, in a preferred embodiment of the present application, referring to Figure 1 , the first lens 1 is a double convex lens; the second lens 2 is a double concave lens; the third lens 3 is a double concave lens; the fourth lens 4 is a meniscus lens, and the object side surface thereof is a concave surface; the fifth lens 5 is a double convex lens; the sixth lens 6 is a meniscus lens, and the object side surface thereof is a concave surface; the seventh lens 7 is a double concave lens; the eighth lens 8 is a double convex lens; the ninth lens 9 is a double convex lens; the tenth lens 10 is a double concave lens; the eleventh lens 11 is a double convex lens; the twelfth lens 12 is a double convex lens; and the thirteenth lens 13 is a meniscus lens, and the object side surface thereof is a convex surface.

[0059] Further, the diameter of the image side effective field of view of the microscope objective 1000 is φ, and φ ≤ 2.26mm is satisfied. In this way, the microscope objective 1000 can accurately and sufficiently display the measured object on the image plane of the microscope objective 1000.

[0060] Further, the telecentricity of the main wavelength of the image side of the microscope objective 1000 is A, and -0.05° ≤ A ≤ 0.05° is satisfied.

[0061] In an embodiment provided by the present application, the materials of the first lens 1, the second lens, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, the eighth lens, the ninth lens 9, the tenth lens 10, the eleventh lens 11, the twelfth lens 12, and the thirteenth lens 13 are all set to be Corning Gorilla glass.

[0062] It should be noted that the basic parameter table of the microscope objective 1000 in the embodiment provided by the present application is shown in Table 1, wherein the units of radius and center distance are millimeters (mm).

[0063] Table 1

[0064] radius center distance refractive index dispersion coefficient object plane infinity 1 infinity 1 2 43.76 2.8 1.57 71.6 3 -173.25 11.9 4 -68.17 1.3 1.48 85.3 5 19.28 2.74 6 -18.15 1 1.68 26.8 7 161.19 1.41 8 -31.00 3.3 1.85 30.0 9 -20.62 35.86 10 (stop) 1.7 11 111.3 6 1.68 26.8 12 -31.30 1.26 1.73 32.3 13 -73.40 18.28 14 -753.22 1.4 1.77 29.7 15 41.13 5.36 1.44 95.1 16 -79.0 0.2 17 101.51 4.59 1.44 95.1 18 -52.52 1 1.65 39.5 19 42.56 5 1.55 71.8 20 -128.8 0.2 21 47 5 1.45 90.2 22 -98.2 0.2 23 29.70 3.5 1.55 75.5 24 64.17 35

[0065] It should be noted that the MTF curve of the microscope objective 1000 in the embodiment is shown in FIG. 2, and in the embodiment, the microscope objective 1000 can always ensure a contrast of greater than 0.3 at 1300 lp / mm. Figure 2

[0066] It should be further noted that the axial chromatic aberration curve of the microscope objective 1000 in the embodiment is shown in FIG. 4, the sagittal chromatic aberration curve of the microscope objective 1000 is shown in FIG. 5, and the image field curvature curve of the microscope objective 1000 is shown in FIG. 6. Figure 3 Figure 4 Figure 5

[0067] In the embodiment, the working distance of the microscope objective 1000 is 34 mm, the entrance pupil diameter is 14 mm, the distance between the entrance pupil and the first lens 1 is 46 mm, the effective field of view on the image side is φ2.26 mm, the numerical aperture on the object side is 0.33, the limit resolution reaches 0.8 μm, the field curvature is less than 0.2 μm, the axial chromatic aberration is less than 5 μm, the sagittal chromatic aberration is less than 0.4 μm, the focal length is 20 mm, the imaging is clear, and the design requirements of the optical system are met.

[0068] The present application also provides a microscope imaging system, which comprises the microscope objective 1000 described above. Since the microscope imaging system comprises the microscope objective 1000, the specific structure of the microscope objective 1000 is referred to the above embodiments. Since the microscope objective 1000 of the microscope imaging system adopts all the technical solutions of the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, which will not be described herein.

[0069] The above description is only exemplary embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation made according to the technical concept of the present application, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.​​​​

Claims

1. A microscope objective, characterized in that The microscope objective has an object side and an image side oppositely arranged along the optical axis direction, and comprises, arranged from the object side to the image side in sequence, a first lens with positive focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power, a seventh lens with negative focal power, an eighth lens with positive focal power, a ninth lens with positive focal power, a tenth lens with negative focal power, an eleventh lens with positive focal power, a twelfth lens with positive focal power, a thirteenth lens with positive focal power, and an image surface, so that the numerical aperture of the microscope objective at a ten-fold magnification reaches 0.33, and the working distance of the microscope objective reaches 34 mm. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the twelfth lens, and the thirteenth lens are all arranged as spherical lenses.

2. The microscope objective according to claim 1, characterized in that The microscope objective further comprises a diaphragm arranged between the fourth lens and the fifth lens.

3. The microscope objective according to claim 1, characterized in that The fifth lens and the sixth lens are cemented together, and the cemented lens formed after the cementing of the fifth lens and the sixth lens has positive focal power; and / or, The seventh lens and the eighth lens are cemented together, and the cemented lens formed after the cementing of the seventh lens and the eighth lens has negative focal power; and / or, The ninth lens, the tenth lens, and the eleventh lens are cemented together, and the cemented lens formed after the cementing of the ninth lens, the tenth lens, and the eleventh lens has positive focal power.

4. The microscope objective of claim 1, wherein The focal length of the first lens is f1, the focal length of the second lens is f2, the focal length of the third lens is f3, the focal length of the fourth lens is f4, the focal length of the fifth lens is f5, the focal length of the sixth lens is f6, the focal length of the seventh lens is f7, the focal length of the eighth lens is f8, the focal length of the ninth lens is f9, the focal length of the tenth lens is f10, the focal length of the eleventh lens is f11, the focal length of the twelfth lens is f12, and the focal length of the thirteenth lens is f13, wherein: 62mm < f1 < 60mm, -33mm < f2 < -30, -25mm < f3 < -20mm, 60mm < f4 < 65mm, 35mm < f5 < 38mm, -76mm < f6 < -75mm, -51mm < f7 < -50mm, 60mm < f8 < 65mm, 78mm < f9 < 80mm, -36mm < f10 < -35mm, 55mm < f11 < 60mm, 68mm < f12 < 70mm, and 95mm < f13 < 100mm.

5. The microscope objective of claim 1, wherein The materials of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens, the tenth lens, the eleventh lens, the twelfth lens, and the thirteenth lens are all arranged as Corning Gorilla glass.

6. The microscope objective of claim 1, wherein The first lens is a biconvex lens. The second lens is a biconcave lens. The third lens is a biconcave lens. The fourth lens is a meniscus lens, and the object side surface thereof is a concave surface; The fifth lens is a double convex lens; The sixth lens is a meniscus lens, and the object side surface thereof is a concave surface; The seventh lens is a double concave lens; The eighth lens is a double convex lens; The ninth lens is a double convex lens; The tenth lens is a double concave lens; The eleventh lens is a double convex lens; The twelfth lens is a double convex lens; The thirteenth lens is a meniscus lens, and the object side surface thereof is a convex surface.

7. The microscope objective according to claim 1, characterized in that The effective field of view of the objective lens on the image side has a diameter of φ, and satisfies φ≤2.26 mm.

8. The microscope objective of claim 1, wherein, The objective lens has a chief wavelength of A on the image side, and satisfies -0.05°≤A≤0.05°.

9. A microscopy system, characterized in that, An optical system comprising the objective lens according to any one of claims 1 to 8.

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