Microscopic imaging system and laser precision machining equipment

Abstract

The invention relates to a microscopic imaging system and laser precision machining equipment, the microscopic imaging system comprises an objective lens group and an eyepiece group, and the objective lens group and the eyepiece group are arranged in sequence along an optical axis from an object plane to an imaging plane. Along the optical axis from the object plane to the imaging plane, the objective lens group sequentially comprises a first lens with positive focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with positive focal power, a seventh lens with positive focal power and an eighth lens with positive focal power; the ninth lens is provided with positive focal power, the tenth lens is provided with negative focal power, the eyepiece group has the amplification factor not less than 10 times, and the sum of the total optical length TTL1 of the objective lens group and the total optical length TTL2 of the eyepiece group is not less than 178.4 mm. Therefore, the microscopic imaging system provided by the invention has a relatively large amplification factor and also has a relatively good optical total length.

Description

Technical Field

[0001] The present application relates to the field of microscopic imaging technology, and in particular to a microscopic imaging system and laser precision processing equipment. Background Art

[0002] The microscopic imaging system is an important component of laser precision processing equipment. It can observe and monitor the processing process in real time, and can also automatically focus online to ensure that the laser beam is always in the correct position of the workpiece. It plays an important role in improving processing accuracy and efficiency.

[0003] In order to improve the magnification, the microscopic imaging system in the related technology usually greatly increases the length of the microscopic imaging system along the optical axis, which ultimately causes a significant increase in the volume and weight of the microscopic imaging system, affecting the convenience of operation. It also causes the light to experience more scattering and absorption in the longer optical path, which affects the clarity of the image.

[0004] That is, when the magnification of the microscopic imaging system in the related art is increased, the size of the microscopic imaging system along the optical axis direction is easily increased. Summary of the invention

[0005] Based on this, it is necessary to provide a microscopic imaging system and laser precision processing equipment to address the problem that the size of the microscopic imaging system along the optical axis is easily increased when the magnification is increased in the related art.

[0006] According to one aspect of the present application, a microscopic imaging system is provided, the microscopic imaging system comprising:

[0007] an objective lens group, along the direction from the object plane to the imaging plane of the optical axis, the objective lens group sequentially 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 and a tenth lens, the first lens has positive focal power, the second lens has positive focal power, the third lens has positive focal power, the fourth lens has positive focal power, the fifth lens has positive focal power, the sixth lens has positive focal power, the seventh lens has positive focal power, the eighth lens has positive focal power, the ninth lens has positive focal power, and the tenth lens has negative focal power; and

[0008] An eyepiece group, along the direction of the optical axis from the object plane to the imaging plane, the objective lens group and the eyepiece group are arranged in sequence, the objective lens group has a magnification of not less than 19 times, the eyepiece group has a magnification of not less than 10 times, and the total optical length TTL1 of the objective lens group and the total optical length TTL2 of the eyepiece group satisfy: TTL1+TTL2≤178.4mm.

[0009] In one embodiment, the object side surface of the first lens is concave, and the image side surface is convex;

[0010] The object side surface of the second lens is concave, and the image side surface is convex;

[0011] The object side surface of the third lens is concave, and the image side surface is convex;

[0012] The object side surface of the fourth lens is concave, and the image side surface is convex;

[0013] The object side surface of the fifth lens is convex, and the image side surface is convex;

[0014] The object side surface of the sixth lens is convex, and the image side surface is concave;

[0015] The object side surface of the seventh lens is convex, and the image side surface is concave;

[0016] The object side surface of the eighth lens is concave, and the image side surface is convex;

[0017] The object side surface of the ninth lens is a concave surface, and the image side surface is a convex surface;

[0018] The object side surface of the tenth lens is a concave surface, and the image side surface is a concave surface;

[0019] The distance WD between the image side surface of the first lens and the object plane and the focal length F1 of the objective lens group satisfy: 1.99≤WD / F1≤4.99, and the interval d78 between the seventh lens and the eighth lens along the optical axis direction satisfies: 0.10≤d78 / TTL1≤0.50.

[0020] In one embodiment, the focal length f1 of the first lens and the focal length F1 of the objective lens group satisfy: 14.20≤f1 / F1≤20.23; the central curvature radius R11 of the image side surface of the first lens and the central curvature radius R12 of the object side surface thereof satisfy: -6.15≤(R11+R12) / (R11-R12)≤-2.15; the thickness d1 of the first lens along the optical axis direction satisfies: 0.01≤d1 / TTL1≤0.11; and / or

[0021] The focal length f2 of the second lens and the focal length F1 of the objective lens group satisfy: 15.77≤f2 / F1≤20.70; the central curvature radius R21 of the image side surface of the second lens and the central curvature radius R22 of the object side surface of the second lens satisfy: -7.68≤(R21+R22) / (R21-R22)≤-0.47; the thickness d2 of the second lens along the optical axis direction satisfies: 0.01≤d2 / TTL1≤0.10; and / or

[0022] The focal length f3 of the third lens and the focal length F1 of the objective lens group satisfy: 33.30≤f3 / F1≤40.00; the central curvature radius R31 of the image side surface of the third lens and the central curvature radius R32 of the object side surface thereof satisfy: -8.15≤(R31+R32) / (R31-R32)≤-0.13; the thickness d3 of the third lens along the optical axis direction satisfies: 0.01≤d3 / TTL1≤0.09; and / or

[0023] The focal length f4 of the fourth lens and the focal length F1 of the objective lens group satisfy: 30.17≤f4 / F1≤35.38; the central curvature radius R41 of the image side surface of the fourth lens and the central curvature radius R42 of the object side surface of the fourth lens satisfy: -3.25≤(R41+R42) / (R41-R42)≤-0.11; the thickness d4 of the fourth lens along the optical axis direction satisfies: 0.01≤d4 / TTL1≤0.08; and / or

[0024] The focal length f5 of the fifth lens and the focal length F1 of the objective lens group satisfy: 33.70≤f5 / F1≤40.22; the central curvature radius R51 of the image side surface of the fifth lens and the central curvature radius R52 of the object side surface thereof satisfy: 0.09≤(R51+R52) / (R51-R52)≤0.10; the thickness d5 of the fifth lens along the optical axis direction satisfies: 0.01≤d5 / TTL1≤0.07; and / or

[0025] The focal length f6 of the sixth lens and the focal length F1 of the objective lens group satisfy: 35.80≤f6 / F1≤42.10; the central curvature radius R61 of the image side surface of the sixth lens and the central curvature radius R62 of the object side surface thereof satisfy: 0.17≤(R61+R62) / (R61-R62)≤5.03; the thickness d6 of the sixth lens along the optical axis direction satisfies: 0.01≤d6 / TTL1≤0.40; and / or

[0026] The focal length f7 of the seventh lens and the focal length F1 of the objective lens group satisfy: 38.81≤f7 / F1≤45.17; the central curvature radius R71 of the image side surface of the seventh lens and the central curvature radius R72 of the object side surface thereof satisfy: 1.25≤(R71+R72) / (R71-R72)≤7.36; the thickness d7 of the seventh lens along the optical axis direction satisfies: 0.01≤d7 / TTL1≤0.12; and / or

[0027] The focal length f8 of the eighth lens and the focal length F1 of the objective lens group satisfy: 306.10≤f8 / F1≤314.62; the central curvature radius R81 of the image side surface of the eighth lens and the central curvature radius R82 of the object side surface of the eighth lens satisfy: 10.18≤(R81+R82) / (R81-R82)≤29.91; the thickness d8 of the eighth lens along the optical axis direction satisfies: 0.01≤d8 / TTL1≤0.08; and / or

[0028] The focal length f9 of the ninth lens and the focal length F1 of the objective lens group satisfy: 25.35≤f9 / F1≤31.20; the central curvature radius R91 of the image side surface of the ninth lens and the central curvature radius R92 of the object side surface thereof satisfy: -80.53≤(R91+R92) / (R91-R92)≤-20.10; the thickness d9 of the ninth lens along the optical axis direction satisfies: 0.01≤d9 / TTL1≤0.05; and / or

[0029] The focal length f10 of the tenth lens and the focal length F1 of the objective lens group satisfy: -3.18≤f10 / F1≤-1.47; the central curvature radius R101 of the image side surface of the tenth lens and the central curvature radius R102 of the object side surface thereof satisfy: 0.01≤(R101+R102) / (R101-R102)≤0.44; the thickness d10 of the tenth lens along the optical axis direction satisfies: 0.01≤d10 / TTL1≤0.03.

[0030] In one embodiment, along the direction of the optical axis from the object plane to the imaging plane, the eyepiece assembly includes:

[0031] The eleventh lens has positive refractive power, and its object side surface is convex and its image side surface is concave;

[0032] A first cemented lens group having positive optical power;

[0033] a second cemented lens group having positive optical power; and

[0034] The sixteenth lens having negative optical power has a convex object-side surface and a concave image-side surface.

[0035] In one embodiment, the focal length f11 of the eleventh lens and the focal length F2 of the eyepiece assembly satisfy: -2.76≤f11 / F2≤-1.31; the central curvature radius L1 of the image side surface of the eleventh lens and the central curvature radius L2 of the object side surface of the eleventh lens satisfy: 0.62≤L1 / L2≤1.83; the thickness d11 of the eleventh lens along the optical axis direction satisfies: 0.001≤d11 / TTL2≤0.004; and / or

[0036] The focal length f16 of the sixteenth lens and the focal length F2 of the eyepiece group satisfy: -0.83≤f16 / F2≤-0.29; the central curvature radius L3 of the image side surface of the sixteenth lens and the central curvature radius L4 of the object side surface satisfy: 1.68≤L3 / L4≤2.73; the thickness d16 of the sixteenth lens along the optical axis direction satisfies: 0.05≤d16 / TTL2≤0.09.

[0037] In one embodiment, along the direction from the object plane to the imaging plane of the optical axis, the first cemented lens group includes a twelfth lens and a thirteenth lens cemented to each other, the twelfth lens has positive focal power, and the object side surface of the twelfth lens is convex, and the image side surface is convex, the thirteenth lens has negative focal power, and the object side surface of the thirteenth lens is concave, and the image side surface is convex; and / or

[0038] Along the direction from the object plane to the imaging plane of the optical axis, the second cemented lens group includes a fourteenth lens and a fifteenth lens cemented to each other, the fourteenth lens has negative optical power, and the object side surface of the fourteenth lens is convex, and the image side surface is concave, and the fifteenth lens has positive optical power, and the object side surface of the fifteenth lens is convex, and the image side surface is convex.

[0039] In one embodiment, the focal length f12 of the twelfth lens and the focal length F2 of the eyepiece assembly satisfy: -10.15≤f12 / F2≤-9.05; the central curvature radius L5 of the image side surface of the twelfth lens and the central curvature radius L6 of the object side surface of the twelfth lens satisfy: -2.29≤L5 / L6≤-0.35; the thickness d12 of the twelfth lens along the optical axis direction satisfies: 0.08≤d12 / TTL2≤0.20; and / or

[0040] The focal length f13 of the thirteenth lens and the focal length F2 of the eyepiece assembly satisfy: 5.80≤f13 / F2≤6.64; the central curvature radius L7 of the image side surface of the thirteenth lens and the central curvature radius L8 of the object side surface of the thirteenth lens satisfy: 0.00≤L7 / L8≤0.98; the thickness d13 of the thirteenth lens along the optical axis direction satisfies: 0.02≤d13 / TTL2≤0.06; and / or

[0041] The focal length f14 of the fourteenth lens and the focal length F2 of the eyepiece assembly satisfy: 1.34≤f14 / F2≤2.28; the central curvature radius L9 of the image side surface of the fourteenth lens and the central curvature radius L10 of the object side surface of the fourteenth lens satisfy: 0.55≤L9 / L10≤1.20; the thickness d14 of the fourteenth lens along the optical axis direction satisfies: 0.03≤d14 / TLT2≤0.07; and / or

[0042] The focal length f15 of the fifteenth lens and the focal length F2 of the eyepiece group satisfy: 58.17≤f15 / F2≤59.66; the central curvature radius L11 of the image side surface of the fifteenth lens and the central curvature radius L12 of the object side surface of the fifteenth lens satisfy: -1.93≤L11 / L12≤-0.45; the thickness d15 of the fifteenth lens along the optical axis direction satisfies: 0.04≤d15 / TLT2≤0.08.

[0043] In one embodiment, the objective lens group further includes a first aperture, and the eyepiece lens group further includes a second aperture. Along the direction from the object plane to the imaging plane along the optical axis, and along the direction from the object plane to the imaging plane along the optical axis, the first aperture is arranged on the side of the tenth lens facing the imaging plane, and the second aperture is arranged on the side of the eleventh lens facing the observed object, and the diameter a of the first aperture and the diameter b of the second aperture satisfy:

[0044] ba ≥ 4.30; and / or

[0045] The numerical aperture NA of the objective lens group and the focal length F1 of the objective lens group satisfy:

[0046] 1.04≤NA*F1≤2.14.

[0047] In one embodiment, the first lens to the sixteenth lens are all spherical lenses.

[0048] According to another aspect of the present application, there is provided a laser precision processing device, comprising the microscopic imaging system in any one of the above embodiments.

[0049] The above-mentioned microscopic imaging system can achieve a magnification of at least 190 times through the cooperation of the objective lens group and the eyepiece group, and the sum of the total optical lengths of the objective lens group and the eyepiece group is not greater than 178.4 mm. In this way, the microscopic imaging system of the present application has a larger magnification while also having a better total optical length. Thus, while increasing the magnification, the volume and weight of the microscopic imaging system will not be greatly increased. That is, the present application can have both a larger magnification and a smaller size along the optical axis. Thereby, the ease of operation of the microscopic imaging system of the present application will not be affected, and the light will not pass through a longer path to cause more scattering and absorption, and thus will not have an excessive impact on the clarity of the image, so that the present application still has better imaging clarity. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 Schematic diagram of the structure of an objective lens assembly in one embodiment of the present application.

[0051] Figure 2 Schematic diagram of the structure of an eyepiece assembly in one embodiment of the present application.

[0052] Figure 3 For this application Figure 1 The point diagram of the objective lens group of the illustrated embodiment, wherein the radius of the Airy disk is 0.468 um and the radius of the spot of the maximum field of view is 0.231 um.

[0053] Figure 4 for Figure 1 Light fan diagram of the objective lens assembly in the illustrated embodiment.

[0054] Figure 5 for Figure 1 Field curvature distortion diagram of the objective lens assembly in the illustrated embodiment.

[0055] Figure 6 for Figure 1 Grid distortion diagram of the objective lens assembly in the illustrated embodiment.

[0056] Figure 7 for Figure 1 Modulation transfer function curve diagram of the objective lens assembly in the illustrated embodiment.

[0057] Figure 8 for Figure 1 Wavefront diagram of the objective lens assembly in the illustrated embodiment.

[0058] Fig. 9 For this application Figure 2 The spot diagram of the eyepiece assembly of the illustrated embodiment, wherein the Airy disk radius is 3.577 um and the spot radius of the maximum field of view is 1.182 um.

[0059] Fig.10 for Figure 2 Light fan diagram of the eyepiece assembly in the illustrated embodiment.

[0060] Fig.11 for Figure 2 Axial aberration diagram of the eyepiece set in the illustrated embodiment.

[0061] Fig.12 for Figure 2 Grid distortion diagram of the eyepiece set in the illustrated embodiment.

[0062] Fig.13 for Figure 2 Modulation transfer function graph of the eyepiece set in the illustrated embodiment.

[0063] Fig.14 for Figure 2 Wavefront diagram of the eyepiece set in the illustrated embodiment.

[0064] Fig.15 for Figure 2 A diagram of vertical axial chromatic aberration of the eyepiece set in the illustrated embodiment.

[0065] Description of Figure Numbers:

[0066] 100, objective lens group;

[0067] 200, eyepiece set;

[0068] L1, first lens; L2, second lens; L3, third lens; L4, fourth lens; L5, fifth lens; L6, sixth lens; L7, seventh lens; L8, eighth lens; L9, ninth lens; L10, tenth lens; L11, eleventh lens; L12, twelfth lens; L13, thirteenth lens; L14, fourteenth lens; L15, fifteenth lens; L16, sixteenth lens; 17, prism; 18, first aperture; 19, second aperture; 21, object plane; 22, imaging plane. DETAILED DESCRIPTION

[0069] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0070] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0071] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0072] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; 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, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0073] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0074] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0075] The coaxial observation microscope imaging system uses the refraction principle of the lens to form a magnified image of the object. It is usually composed of an objective lens, an eyepiece, and an illumination system. The objective lens is responsible for forming a real image of the object in the focal plane of the eyepiece, while the eyepiece magnifies this real image again so that the observer can see the magnified image of the object.

[0076] The coaxial observation microscopic imaging system in laser precision processing equipment mainly plays the role of observing and monitoring the processing process, and provides the laser precision processing equipment with accurate analysis and measurement capabilities of microstructures. In order to improve the magnification of the microscopic imaging system in the related technology, it is usually achieved by increasing the length of the microscopic imaging system along the optical axis, but at the same time it will increase the volume and weight of the microscopic imaging system, affecting the convenience of operation, and will cause the light to experience more scattering and absorption in the longer optical path, which will affect the clarity of the image.

[0077] Based on this, the present application provides a microscopic imaging system and a laser precision machining device. The microscopic imaging system is used in the laser precision machining device, and can increase the magnification while making the microscopic imaging system have a shorter or better size along the optical axis.

[0078] See 1 and Figure 2 As shown, Figure 1 FIG. 1 is a schematic structural diagram of an objective lens assembly 100 in an embodiment of the present application. Figure 2 FIG. 2 is a schematic diagram of the structure of an eyepiece assembly 200 in an embodiment of the present application.

[0079] The present application provides a microscopic imaging system, which includes an objective lens group 100 and an eyepiece group 200. The objective lens group 100 and the eyepiece group 200 are arranged in sequence along the direction from the object plane 21 to the imaging plane 22 of the optical axis. The objective lens group 100 has a magnification of not less than 19 times, the eyepiece group 200 has a magnification of not less than 10 times, and the total optical length TTL1 of the objective lens group 100 and the total optical length TTL2 of the eyepiece group 200 satisfy: TTL1+TTL2≤178.4mm.

[0080] The microscopic imaging system of the present application can achieve a magnification of at least 190 times through the cooperation of the objective lens group 100 and the eyepiece group 200, and the sum of the total optical lengths of the objective lens group 100 and the eyepiece group 200 is not greater than 178.4 mm. The microscopic imaging system of the present application has a large magnification and a better total optical length. Thus, while increasing the magnification, the volume and weight of the microscopic imaging system will not be greatly increased. The volume and weight of the microscopic imaging system will not be greatly increased, so that the ease of operation of the microscopic imaging system of the present application will not be affected, and the light will not pass through a longer path to cause more scattering and absorption, and thus will not cause too much impact on the clarity of the image, so that the present application still has better image clarity.

[0081] In some embodiments, see Figure 1 As shown, along the direction from the object plane 21 to the imaging plane 22 of the optical axis, the objective lens group 100 sequentially includes a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, an eighth lens L8, a ninth lens L9 and a tenth lens L10.

[0082] The first lens L1 has positive focal power, and its object side surface is concave, and its image side surface is convex. Thus, the working aperture of the first lens L1 can be reduced while the light collecting ability of the edge field of view is improved. The second lens L2 has positive focal power, and its object side surface is concave, and its image side surface is convex. The third lens L3 has positive focal power, and its object side surface is concave, and its image side surface is convex. The fourth lens L4 has positive focal power, and its object side surface is concave, and its image side surface is convex. The fifth lens L5 has positive focal power, and its object side surface is convex, and its image side surface is convex. The sixth lens L6 has positive focal power, and its object side surface is convex, and its image side surface is concave. The seventh lens L7 has positive focal power, and its object side surface is convex, and its image side surface is concave. The eighth lens L8 has positive focal power, and its object side surface is concave, and its image side surface is convex. The ninth lens L9 has positive focal power, and its object side surface is concave, and its image side surface is convex. The tenth lens L10 has negative refractive power, and the object-side surface and image-side surface of the tenth lens L10 are concave.

[0083] It can be understood that the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 are all meniscus lenses with positive focal power, and their concave surfaces are all facing the object side, so that the ability to collect light from the edge field of view can be improved while reducing the working aperture of the first lens L1. And the use of multiple meniscus lenses can also well correct the trend of light, reduce spherical aberration, make the light imaged on the imaging surface 22, and improve the imaging quality. The object side and image side of the fifth lens L5 are both convex, which can reduce the influence of the coma generated by the fifth lens L5 itself on the imaging of the microscopic imaging system, balance various aberrations of the microscopic imaging system, and improve the imaging quality of the microscopic imaging system. The sixth lens L6 and the seventh lens L7 are both meniscus lenses, and the object side of both are convex and the image side are concave, which is conducive to collecting light from the edge field of view, so that the collected light can smoothly enter the rear optical system, and further make the light trend smoothly transition. It is also conducive to converging light while improving the relative illumination of the microscopic imaging system, so that the brightness of the microscopic imaging system at the imaging surface 22 is improved to avoid the generation of dark corners. And the seventh lens L7 can cooperate with the sixth lens L6, which is beneficial to converge the light while reducing the light deflection angle, so that the light trend transitions smoothly. The setting of the eighth lens L8 and the ninth lens L9 reduces the light deflection angle, making the light trend more stable. And the eighth lens L8 and the ninth lens L9 cooperate with the seventh lens L7 to further correct the light trend, reduce spherical aberration, make the light imaged on the imaging surface 22, and improve the imaging quality. The design of the tenth lens L10 is conducive to increasing the imaging area of ​​the optical lens and improving the imaging quality of the optical lens. The tenth lens L10 can be used in conjunction with the positive and negative optical powers of the ninth lens L9, which can well correct spherical aberration, coma and field curvature, which is beneficial to improving the imaging quality of the microscopic imaging system.

[0084] It can be understood that the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the sixth lens L6, the seventh lens L7, the eighth lens L8 and the ninth lens L9 are all meniscus lenses. The meniscus lenses with positive or negative optical power are used in conjunction with each other to well correct the trend of light, reduce spherical aberration, make the light imaged on the imaging surface 22, and improve the imaging quality.

[0085] In some embodiments, the distance WD between the image side surface of the first lens L1 and the object surface 21 and the focal length F1 of the objective lens group 100 satisfy: 1.99≤WD / F1≤4.99. The interval d78 between the seventh lens L7 and the eighth lens L8 along the optical axis direction satisfies: 0.10≤d78 / TTL1≤0.50. Meeting the above range is conducive to the objective lens group 100 of the present application having a shorter or better axial dimension, and is conducive to the microscopic imaging system having a larger magnification and a better optical total length. Therefore, while increasing the magnification, the volume and weight of the microscopic imaging system will not be greatly increased.

[0086] In some embodiments, the focal length f1 of the first lens L1 and the focal length F1 of the objective lens group 100 satisfy: 14.20≤f1 / F1≤20.23, the central curvature radius R11 of the image side surface of the first lens L1 and the central curvature radius R12 of the object side surface thereof satisfy: -6.15≤(R11+R12) / (R11-R12)≤-2.15, and the thickness d1 of the first lens L1 along the optical axis direction satisfies: 0.01≤d1 / TTL1≤0.11. Meeting the above range can effectively limit the length of the objective lens group 100, which is conducive to miniaturization of the microscopic imaging system. At the same time, the first lens L1 can have an appropriate positive focal power, which can improve the light collection capability of the edge field of view while reducing the working aperture of the first lens L1. And the first lens L1 has a suitable thickness, which is conducive to shortening the size of the objective lens group 100 along the optical axis.

[0087] The focal length f2 of the second lens L2 and the focal length F1 of the objective lens group 100 satisfy: 15.77≤f2 / F1≤20.70, the central curvature radius R21 of the image side surface of the second lens L2 and the central curvature radius R22 of the object side surface thereof satisfy: -7.68≤(R21+R22) / (R21-R22)≤-0.47, and the thickness d2 of the second lens L2 along the optical axis direction satisfies: 0.01≤d2 / TTL1≤0.10. When the above range is met, the second lens L2 can have an appropriate positive focal power, so that it can cooperate with the first lens L1, which is conducive to the smooth transition of light and the improvement of imaging quality. In addition, the second lens L2 has an appropriate thickness, which is conducive to reducing the size of the objective lens group 100 along the optical axis.

[0088] The focal length f3 of the third lens L3 and the focal length F1 of the objective lens group 100 satisfy: 33.30≤f3 / F1≤40.00, the central curvature radius R31 of the image side surface of the third lens L3 and the central curvature radius R32 of the object side surface thereof satisfy: -8.15≤(R31+R32) / (R31-R32)≤-0.13, and the thickness d3 of the third lens L3 along the optical axis direction satisfies: 0.01≤d3 / TTL1≤0.09. When the above range is met, the third lens L3 can have an appropriate positive focal power, share the positive focal power of the front end of the objective lens group 100, make the light converge smoothly, and be beneficial to improve the imaging quality. And the third lens L3 has a suitable thickness, which is beneficial to reduce the size of the objective lens group 100 along the optical axis.

[0089] The focal length f4 of the fourth lens L4 and the focal length F1 of the objective lens group 100 satisfy: 30.17≤f4 / F1≤35.38, the central curvature radius R41 of the image side surface of the fourth lens L4 and the central curvature radius R42 of the object side surface thereof satisfy: -3.25≤(R41+R42) / (R41-R42)≤-0.11, and the thickness d4 of the fourth lens L4 along the optical axis direction satisfies: 0.01≤d4 / TTL1≤0.08. When the above range is met, the fourth lens L4 can have an appropriate positive focal power, so that it can cooperate with the third lens L3, which is beneficial to the smooth transition of light and the improvement of imaging quality. In addition, the fourth lens L4 has an appropriate thickness, which is beneficial to reducing the size of the objective lens group 100 along the optical axis.

[0090] The focal length f5 of the fifth lens L5 and the focal length F1 of the objective lens group 100 satisfy: 33.70≤f5 / F1≤40.22, the central curvature radius R51 of the image side surface of the fifth lens L5 and the central curvature radius R52 of the object side surface thereof satisfy: 0.09≤(R51+R52) / (R51-R52)≤0.10, and the thickness d5 of the fifth lens L5 along the optical axis direction satisfies: 0.01≤d5 / TTL1≤0.07. When the above range is satisfied, the fifth lens L5 can have an appropriate positive focal power, and cooperate with the first lens L1, the second lens L2, the third lens L3 and the fourth lens L4 to share the positive focal power of the front end of the objective lens group 100, so that the light can transition smoothly. While improving the light convergence ability, it is conducive to the smooth transition of light. At the same time, it is conducive to correcting the spherical aberration and coma of the objective lens group 100, and improving the imaging quality of the objective lens group 100. That is, it is beneficial to correct various aberrations of the objective lens group 100 and improve the imaging quality of the objective lens group 100. The fifth lens L5 has a suitable thickness, which is beneficial to reducing the size of the objective lens group 100 along the optical axis.

[0091] The focal length f6 of the sixth lens L6 and the focal length F1 of the objective lens group 100 satisfy: 35.80≤f6 / F1≤42.10, the central curvature radius R61 of the image side surface of the sixth lens L6 and the central curvature radius R62 of the object side surface thereof satisfy: 0.17≤(R61+R62) / (R61-R62)≤5.03, and the thickness d6 of the sixth lens L6 along the optical axis direction satisfies: 0.01≤d6 / TTL1≤0.40. Meeting the above ranges can make the sixth lens L6 have a better positive focal power, and is conducive to collecting the edge field light, so that the collected light can smoothly enter the rear optical system, and further make the light trend smoothly transition. At the same time, the sixth lens L6 has a suitable thickness, which is conducive to reducing the size of the objective lens group 100 along the optical axis.

[0092] The focal length f7 of the seventh lens L7 and the focal length F1 of the objective lens group 100 satisfy: 38.81≤f7 / F1≤45.17, the central curvature radius R71 of the image side surface of the seventh lens L7 and the central curvature radius R72 of the object side surface thereof satisfy: 1.25≤(R71+R72) / (R71-R72)≤7.36, and the thickness d7 of the seventh lens L7 along the optical axis direction satisfies: 0.01≤d7 / TTL1≤0.12. Meeting the above ranges can make the seventh lens L7 have a better positive focal power, which is beneficial to its cooperation with the sixth lens L6, and is beneficial to reducing the light deflection angle while converging the light, so that the light transitions smoothly. It is also beneficial for it to collect the edge field light, so that the collected light can smoothly enter the rear optical system, and further make the light transition smoothly. It is beneficial for the seventh lens L7 to converge the light while improving the relative illumination of the microscopic imaging system, so that the brightness of the microscopic imaging system at the imaging surface 22 is improved to avoid the generation of dark corners. Meanwhile, the seventh lens L7 has a suitable thickness, which is beneficial to reducing the size of the objective lens group 100 along the optical axis.

[0093] The focal length f8 of the eighth lens L8 and the focal length F1 of the objective lens group 100 satisfy: 306.10≤f8 / F1≤314.62, the central curvature radius R81 of the image side surface of the eighth lens L8 and the central curvature radius R82 of the object side surface thereof satisfy: 10.18≤(R81+R82) / (R81-R82)≤29.91; the thickness d8 of the eighth lens L8 along the optical axis direction satisfies: 0.01≤d8 / TTL1≤0.08. Meeting the above ranges can make the eighth lens L8 have a better positive focal power, which is beneficial to its cooperation with the seventh lens L7, making the light trend more stable, while helping to reduce spherical aberration and improve imaging quality. At the same time, the eighth lens L8 has a suitable thickness, which is beneficial to reducing the size of the objective lens group 100 along the optical axis.

[0094] The focal length f9 of the ninth lens L9 and the focal length F1 of the objective lens group 100 satisfy: 25.35≤f9 / F1≤31.20, the central curvature radius R91 of the image side surface of the ninth lens L9 and the central curvature radius R92 of the object side surface thereof satisfy: -80.53≤(R91+R92) / (R91-R92)≤-20.10, and the thickness d9 of the ninth lens L9 along the optical axis direction satisfies: 0.01≤d9 / TTL1≤0.05. When the above range is satisfied, the ninth lens L9 can have a better positive focal power, and while the eighth lens L8 cooperates with the seventh lens L7 to eliminate the spherical aberration, the setting of the ninth lens L9 is conducive to making the light trend after passing through the eighth lens L8 more stable, which is conducive to further improving the imaging quality. At the same time, the ninth lens L9 has a suitable thickness, which is conducive to reducing the size of the objective lens group 100 along the optical axis.

[0095] The focal length f10 of the tenth lens L10 and the focal length F1 of the objective lens group 100 satisfy: -3.18≤f10 / F1≤-1.47, the central curvature radius R101 of the image side surface of the tenth lens L10 and the central curvature radius R102 of the object side surface thereof satisfy: 0.01≤(R101+R102) / (R101-R102)≤0.44, and the thickness d10 of the tenth lens L10 along the optical axis direction satisfies: 0.01≤d10 / TTL1≤0.03. When the above range is satisfied, the tenth lens L10 can have a better negative focal power, which is beneficial to increase the imaging area of ​​the optical lens, and share the negative focal power of the objective lens group 100, while correcting the spherical aberration and coma of the objective lens group 100, making the light transition smoothly, and improving the imaging quality of the objective lens group 100. In addition, the tenth lens L10 has a suitable thickness, which is beneficial to reduce the size of the objective lens group 100 along the optical axis.

[0096] In some embodiments, refer to Table 1 below, which shows the relevant parameters of each lens in the objective lens assembly 100 .

[0097] Table 1

[0098]

[0099] Wherein, thickness refers to the distance between two adjacent optical surfaces. For example, the thickness of the object side surface of the first lens L1 refers to the distance between the object side surface of the first lens L1 and the object surface 21, and the thickness of the image side surface of the first lens L1 refers to the distance between the image side surface of the first lens L1 and the object side surface. The rest are by analogy, and will not be repeated here.

[0100] In some embodiments, see Figure 3 As shown, Figure 3 For this application Figure 1The spot diagram of the objective lens group 100 of the embodiment shown shows the imaging of the objective lens group 100. The radius of the Airy disk is 0.468um, and the spot radius of the maximum field of view is 0.231um. Combined with the diagram, it can be seen that most of the diffuse spots are concentrated within the Airy disk, indicating that the imaging quality of the objective lens group 100 is relatively good.

[0101] See also Figure 4 , Figure 4 for Figure 1 The light fan diagram of the objective lens assembly 100 in the illustrated embodiment shows the aberration correction of the objective lens assembly 100. As can be seen from the diagram, aberrations such as spherical aberration, coma and astigmatism of the objective lens assembly 100 are effectively corrected.

[0102] See also Figure 5 , Figure 5 for Figure 1 The field curvature distortion diagram of the objective lens assembly 100 in the illustrated embodiment shows the field curvature and distortion of the objective lens assembly 100. As can be seen from the diagram, the ideal image plane and the actual image plane almost completely overlap; the distortion meets the imaging quality requirements.

[0103] See also Figure 6 , Figure 6 for Figure 1 The grid distortion diagram of the objective lens assembly 100 in the illustrated embodiment shows the distortion of the objective lens assembly 100. As can be seen from the diagram, the actual image and the ideal image almost completely overlap, and the objective lens assembly 100 has good imaging quality.

[0104] See also Figure 7 , Figure 7 for Figure 1 The modulation transfer function curve of the objective lens assembly 100 in the illustrated embodiment shows the imaging quality of the objective lens assembly 100. As can be seen from the figure, the curves of different fields of view and the diffraction limit almost completely coincide, so that the objective lens assembly 100 has higher resolution and clarity, and better imaging quality.

[0105] See also Figure 8 , Figure 8 for Figure 1 The wavefront diagram of the objective lens group 100 in the illustrated embodiment shows the wave aberration of the objective lens group 100. As can be seen from the figure, the wave aberration of the objective lens group 100 is much smaller than the requirement of the imaging system, indicating that the imaging quality of the objective lens group 100 is good.

[0106] In some embodiments, see Figure 2As shown, along the direction from the object plane 21 to the imaging plane 22 along the optical axis, the eyepiece group 200 includes a prism 17, an eleventh lens L11, a first cemented lens group, a second cemented lens group and a sixteenth lens L16 in sequence, wherein a semi-transparent and semi-reflective film is provided inside the prism 17, and the prism 17 is used to receive the light emitted by the light source provided on one side of the optical axis, and change the propagation direction of the received light through the semi-transparent and semi-reflective film, so that the light propagates along the optical axis toward the objective lens group 100, so that the light source light and the imaging optical axis are coaxial. Afterwards, the objective lens group 100 forms a real image of the object in the focal plane of the eyepiece group 200, and the eyepiece group 200 magnifies the real image again, so that the observer can see the magnified object image.

[0107] The eleventh lens L11 has positive focal power, and its object side surface is convex, and its image side surface is concave. It can be understood that the eleventh lens L11 is a meniscus lens, and its concave surface faces the imaging surface 22, which is conducive to collecting the edge field light, so that the collected light can smoothly enter the rear optical system, and further make the light trend smoothly transition. It is also conducive to converging light while improving the relative illumination of the microscopic imaging system, so that the brightness of the microscopic imaging system at the imaging surface 22 is improved to avoid the generation of dark corners.

[0108] The first cemented lens group and the second cemented lens group both have positive focal lengths, which are beneficial for converging light while reducing the angle of light deflection, allowing the light to transition smoothly. The sixteenth lens L16 has negative focal length, with a convex object side and a concave image side. This is beneficial for collecting light from the edge of the field of view, allowing the collected light to smoothly enter the back-end optical system, and further allowing the light to transition smoothly.

[0109] In some embodiments, continue to refer to Figure 2 As shown, along the direction from the object plane 21 to the imaging plane 22 of the optical axis, the first cemented lens group includes a twelfth lens L12 and a thirteenth lens L13 cemented to each other, the twelfth lens L12 has positive refractive power, and the object side surface of the twelfth lens L12 is convex, and the image side surface is convex, the thirteenth lens L13 has negative refractive power, and the object side surface of the thirteenth lens L13 is concave, and the image side surface is convex.

[0110] The twelfth lens L12 and the thirteenth lens L13 cooperate and are glued together to effectively correct the chromatic aberration of the eyepiece group 200, balance the aberration of the eyepiece group 200, and improve the imaging quality of the eyepiece group 200. They can also reduce the eccentricity sensitivity of the eyepiece group 200, reduce the assembly sensitivity of the eyepiece group 200, and thus reduce the difficulty of the processing technology of the eyepiece group 200 and improve the assembly yield of the eyepiece group 200. At the same time, the lens glue setting is conducive to reducing the size of the eyepiece group 200 along the optical axis, which is conducive to the miniaturization design of the microscopic imaging system.

[0111] In some embodiments, along the direction of the optical axis from the object plane 21 to the imaging plane 22, the second cemented lens group includes a fourteenth lens L14 and a fifteenth lens L15 that are cemented to each other, the fourteenth lens L14 has a negative optical power, and the object side surface of the fourteenth lens L14 is a convex surface, and the image side surface is a concave surface. The fifteenth lens L15 has a positive optical power, and the object side surface of the fifteenth lens L15 is a convex surface, and the image side surface is a convex surface. The fourteenth lens L14 has a negative optical power, and can cooperate with the fifteenth lens L15 with a positive optical power, which is beneficial to correct the light trend, correct aberrations such as spherical aberration, coma and field curvature, and improve the imaging quality.

[0112] The fourteenth lens L14 and the fifteenth lens L15 are glued together, and the cooperation of the two can further correct the aberration of the eyepiece group 200 and improve the imaging quality of the eyepiece group 200, while also reducing the eccentricity sensitivity of the eyepiece group 200 and reducing the assembly sensitivity of the eyepiece group 200. In addition, the difficulty of the processing technology of the eyepiece group 200 is reduced, and the assembly yield of the eyepiece group 200 is improved. At the same time, the lens glue setting is conducive to reducing the size of the eyepiece group 200 along the optical axis, which is conducive to the miniaturization design of the microscopic imaging system. The fifteenth lens L15 has a positive optical power, and can cooperate with the sixteenth lens L16 with a negative optical power to further correct the light trend, correct the aberration of the light, and improve the imaging quality of the eyepiece group 200.

[0113] In some embodiments, the focal length f11 of the eleventh lens L11 and the focal length F2 of the eyepiece assembly 200 satisfy: -2.76≤f11 / F2≤-1.31, the central curvature radius L1 of the image side surface of the eleventh lens L11 and the central curvature radius L2 of the object side surface thereof satisfy: 0.62≤L1 / L2≤1.83, and the thickness d11 of the eleventh lens L11 along the optical axis direction satisfies: 0.001≤d11 / TTL2≤0.004. Meeting the above range enables the eleventh lens L11 to have a better positive focal power, and is conducive to collecting the edge field light, so that the collected light can smoothly enter the rear optical system, and further make the light trend smoothly transition. At the same time, the eleventh lens L11 has a suitable thickness, which is conducive to reducing the size of the objective lens assembly 100 along the optical axis.

[0114] The focal length f16 of the sixteenth lens L16 and the focal length F2 of the eyepiece group 200 satisfy: -0.83≤f16 / F2≤-0.29; the central curvature radius L3 of the image side surface of the sixteenth lens L16 and the central curvature radius L4 of the object side surface thereof satisfy: 1.68≤L3 / L4≤2.73; the thickness d16 of the sixteenth lens L16 along the optical axis direction satisfies: 0.05≤d16 / TTL2≤0.09. Meeting the above range enables the sixteenth lens L16 to have a better negative focal power, share the negative focal power of the eyepiece group 200, facilitate cooperation with the second cemented lens group, reduce the deflection angle of the light, make the light trend more stable, and facilitate improving the imaging quality. In addition, the sixteenth lens L16 has a suitable thickness, which is conducive to reducing the size of the objective lens group 100 along the optical axis.

[0115] In some embodiments, the focal length f12 of the twelfth lens L12 and the focal length F2 of the eyepiece assembly 200 satisfy: -10.15≤f12 / F2≤-9.05, the central curvature radius L5 of the image side surface of the twelfth lens L12 and the central curvature radius L6 of the object side surface satisfy: -2.29≤L5 / L6≤-0.35, and the thickness d12 of the twelfth lens L12 along the optical axis direction satisfies: 0.08≤d12 / TTL2≤0.20. The focal length f13 of the thirteenth lens L13 and the focal length F2 of the eyepiece group 200 satisfy: 5.80≤f13 / F2≤6.64, the central curvature radius L7 of the image side surface of the thirteenth lens L13 and the central curvature radius L8 of the object side surface satisfy: 0.00≤L7 / L8≤0.98, and the thickness d13 of the thirteenth lens L13 along the optical axis direction satisfies: 0.02≤d13 / TTL2≤0.06.

[0116] Satisfying the above range enables the twelfth lens L12 to have a better positive focal power, and enables the thirteenth lens L13 to have a better negative focal power. The cooperation between the twelfth lens L12 and the thirteenth lens L13 effectively corrects the chromatic aberration of the eyepiece group 200, balances the aberration of the eyepiece group 200, and improves the imaging quality of the eyepiece group 200. In addition, the twelfth lens L12 and the thirteenth lens L13 both have a smaller thickness along the optical axis, and the two are glued together, which is conducive to reducing the size of the eyepiece group 200 along the optical axis, and is conducive to the miniaturization design of the microscopic imaging system.

[0117] In some embodiments, the focal length f14 of the fourteenth lens L14 and the focal length F2 of the eyepiece assembly 200 satisfy: 1.34≤f14 / F2≤2.28, the central curvature radius L9 of the image-side surface of the fourteenth lens L14 and the central curvature radius L10 of the object-side surface thereof satisfy: 0.55≤L9 / L10≤1.20, and the thickness d14 of the fourteenth lens L14 along the optical axis direction satisfies: 0.03≤d14 / TLT2≤0.07. The focal length f15 of the fifteenth lens L15 and the focal length F2 of the eyepiece group 200 satisfy: 58.17≤f15 / F2≤59.66, the central curvature radius L11 of the image side surface of the fifteenth lens L15 and the central curvature radius L12 of the object side surface satisfy: -1.93≤L11 / L12≤-0.45, and the thickness d15 of the fifteenth lens L15 along the optical axis direction satisfies: 0.04≤d15 / TLT2≤0.08.

[0118] When the above range is met, the fourteenth lens L14 can have a better negative focal power, and the fifteenth lens L15 can have a better positive focal power. The fourteenth lens L14 and the fifteenth lens L15 cooperate to effectively correct the chromatic aberration of the eyepiece group 200 and improve the imaging quality of the eyepiece group 200. At the same time, the fourteenth lens L14 and the fifteenth lens L15 both have a smaller thickness along the optical axis, and the two are glued together, which is conducive to reducing the size of the eyepiece group 200 along the optical axis, and is conducive to the miniaturization design of the microscopic imaging system.

[0119] Refer to Table 2 below, which shows the relevant parameters of each lens in the objective lens assembly 100.

[0120] Table 2

[0121]

[0122] Wherein, thickness refers to the distance between two adjacent optical surfaces. For example, the thickness of the object side surface of the eleventh lens L11 refers to the distance from the object side surface of the eleventh lens L11 to the image side surface of the prism 17. The image side surface of the twelfth lens L12 is glued to the object side surface of the thirteenth lens L13, and the image side surface of the fourteenth lens L14 is glued to the object side surface of the fifteenth lens L15. No further details are given here.

[0123] In some embodiments, see Fig. 9 As shown, Fig. 9 For this application Figure 2 The spot diagram of the eyepiece assembly 200 of the illustrated embodiment shows the imaging of the eyepiece assembly 200. The radius of the Airy disk is 3.577um, and the spot radius of the maximum field of view is 1.182um. It can be seen from the figure that the diffuse spots of different wavelengths are all concentrated within the Airy disk, indicating that the imaging quality of the eyepiece assembly 200 is relatively good.

[0124] See also Fig.10 , Fig.10 for Figure 2 The light fan diagram of the eyepiece assembly 200 in the illustrated embodiment shows the aberration correction of the eyepiece assembly 200. As can be seen from the figure, aberrations such as spherical aberration, coma and astigmatism of the eyepiece assembly 200 are effectively corrected.

[0125] See also Fig.11 , Fig.11 for Figure 2 The field curvature distortion diagram of the eyepiece assembly 200 in the illustrated embodiment shows the field curvature and distortion of the eyepiece assembly 200. As can be seen from the diagram, the field curvature curve is relatively flat, indicating that the imaging quality is good.

[0126] See also Fig.12 , Fig.12 for Figure 2 The vertical axis chromatic aberration diagram of the eyepiece assembly 200 in the illustrated embodiment shows the vertical axis chromatic aberration of the eyepiece assembly 200. As can be seen from the diagram, the vertical axis chromatic aberration is within the Airy disk and is almost 0, indicating that the chromatic aberration has been effectively corrected.

[0127] See also Fig.13 , Fig.13 for Figure 2 The grid distortion diagram of the eyepiece assembly 200 in the illustrated embodiment shows the distortion of the eyepiece assembly 200. As can be seen from the diagram, the actual image and the ideal image almost completely overlap, indicating that the eyepiece assembly 200 has good imaging quality.

[0128] See also Fig.14 , Fig.14 for Figure 2 The wavefront diagram of the eyepiece assembly 200 in the illustrated embodiment shows the wave aberration of the eyepiece assembly 200. As can be seen from the figure, the wave aberration of the eyepiece assembly 200 is much smaller than the requirement of the imaging system, indicating that the imaging quality of the eyepiece assembly 200 is good.

[0129] See also Fig.15 , Fig.15 for Figure 2 The modulation transfer function curve of the eyepiece assembly 200 in the illustrated embodiment shows the imaging quality of the eyepiece assembly 200. As can be seen from the figure, the curves of different fields of view and the diffraction limit almost completely coincide, which indicates that the eyepiece assembly 200 has a higher resolution and clarity, and a better imaging quality.

[0130] In some embodiments, in conjunction with Figure 1 and Figure 2As shown, the objective lens group 100 further includes a first aperture 18, and the eyepiece lens group 200 further includes a second aperture 19. Along the direction of the optical axis from the object plane 21 to the imaging plane 22, and along the direction of the optical axis from the object plane 21 to the imaging plane 22, the first aperture 18 is arranged on the side of the tenth lens L10 facing the imaging plane 22, and the second aperture 19 is arranged on the side of the eleventh lens L11 facing the observed object. The diameter a of the first aperture 18 and the diameter b of the second aperture 19 satisfy: ba≥4.30. In this way, the height of the incident light is controlled by the first aperture 18, which is conducive to reducing the high-order aberration and the mechanical aperture of the lens. By arranging the second aperture 19 near the object side of the eleventh lens L11, the generation of ghost images of the microscopic imaging system can be reduced, and it is conducive to converging the light entering the microscopic imaging system and reducing the rear port diameter of the microscopic imaging system.

[0131] In some embodiments, the numerical aperture NA of the objective lens set 100 and the focal length F1 of the objective lens set 100 satisfy: 1.04≤NA*F1≤2.14. If the above range is met, the objective lens set 100 of the present application has better light collection capability and better resolution, which is beneficial to improve the contrast and clarity of imaging.

[0132] In some embodiments, the first lens L1 to the sixteenth lens L16 are all spherical lenses, which have a relatively simple manufacturing process and have many advantages, such as low cost, easy cleaning and maintenance, convenient for combination with other types of lenses (such as aspherical lenses), and easy testing and calibration.

[0133] In some embodiments, the materials of the eleventh lens L11 to the sixteenth lens L16 and the prism 17 are all optical glass, such as silicate glass, lead glass, borosilicate glass, quartz glass, and rare earth glass, etc. This makes the eyepiece assembly 200 of the present application have the advantages of high transparency, easy design, good thermal stability, easy processing, scratch resistance, and low cost.

[0134] In some embodiments, the materials of the first lens L1 to the thirteenth lens L13 are all quartz materials, so that the objective lens assembly 100 of the present application has the advantages of high temperature resistance, corrosion resistance, good thermal stability, good electrical insulation performance, and not easy to be polluted and aged.

[0135] The present application also provides a laser precision processing device, comprising the microscopic imaging system and a housing in any of the above embodiments, wherein the microscopic imaging system is disposed in the housing, and the housing may be a supporting structure for the microscopic imaging system. The microscopic imaging system is used to monitor the processing action of the laser precision processing device and the processed workpiece, and provides the laser precision processing device with accurate microstructure analysis and measurement capabilities.

[0136] The microscopic imaging system of the present application can achieve a magnification of at least 190 times by cooperating with the objective lens group 100 and the eyepiece group 200, and the sum of the total optical lengths of the objective lens group 100 and the eyepiece group 200 is not greater than 178.4 mm. In this way, the microscopic imaging system of the present application has a larger magnification and a better total optical length. Thus, while increasing the magnification, the volume and weight of the microscopic imaging system will not be greatly increased. That is, the present application can have both a larger magnification and a smaller size along the optical axis. Thus, the ease of operation of the microscopic imaging system of the present application will not be affected, and the light will not pass through a longer path to cause more scattering and absorption. Furthermore, the clarity of the imaging will not be greatly affected, so that the present application still has a better imaging clarity. Thus, more accurate monitoring can be provided for laser precision processing equipment.

[0137] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0138] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A microscopic imaging system, characterized in that: The microscopic imaging system comprises: an objective lens group, along the direction from the object plane to the imaging plane of the optical axis, the objective lens group sequentially 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 and a tenth lens, the first lens has positive focal power, the second lens has positive focal power, the third lens has positive focal power, the fourth lens has positive focal power, the fifth lens has positive focal power, the sixth lens has positive focal power, the seventh lens has positive focal power, the eighth lens has positive focal power, the ninth lens has positive focal power, and the tenth lens has negative focal power; and An eyepiece group, along the direction from the object plane to the imaging plane of the optical axis, the objective lens group and the eyepiece group are arranged in sequence, the objective lens group has a magnification of not less than 19 times, the eyepiece group has a magnification of not less than 10 times, and the total optical length TTL1 of the objective lens group and the total optical length TTL2 of the eyepiece group satisfy: TTL1+TTL2≤178.4mm.

2. The microscopic imaging system according to claim 1, characterized in that: The object side surface of the first lens is concave, and the image side surface is convex; The object side surface of the second lens is concave, and the image side surface is convex; The object side surface of the third lens is concave, and the image side surface is convex; The object side surface of the fourth lens is concave, and the image side surface is convex; The object side surface of the fifth lens is convex, and the image side surface is convex; The object side surface of the sixth lens is convex, and the image side surface is concave; The object side surface of the seventh lens is convex, and the image side surface is concave; The object side surface of the eighth lens is concave, and the image side surface is convex; The object side surface of the ninth lens is a concave surface, and the image side surface is a convex surface; The object side surface of the tenth lens is a concave surface, and the image side surface is a concave surface; The distance WD between the image side surface of the first lens and the object plane and the focal length F1 of the objective lens group satisfy: 1.99≤WD / F1≤4.99, and the interval d78 between the seventh lens and the eighth lens along the optical axis direction satisfies: 0.10≤d78 / TTL1≤0.

50.

3. The microscopic imaging system according to claim 2, characterized in that: The focal length f1 of the first lens and the focal length F1 of the objective lens group satisfy: 14.20≤f1 / F1≤20.23; the central curvature radius R11 of the image side surface of the first lens and the central curvature radius R12 of the object side surface of the first lens satisfy: -6.15≤(R11+R12) / (R11-R12)≤-2.15; the thickness d1 of the first lens along the optical axis direction satisfies: 0.01≤d1 / TTL1≤0.11; and / or The focal length f2 of the second lens and the focal length F1 of the objective lens group satisfy: 15.77≤f2 / F1≤20.70; the central curvature radius R21 of the image side surface of the second lens and the central curvature radius R22 of the object side surface of the second lens satisfy: -7.68≤(R21+R22) / (R21-R22)≤-0.47; the thickness d2 of the second lens along the optical axis direction satisfies: 0.01≤d2 / TTL1≤0.10; and / or The focal length f3 of the third lens and the focal length F1 of the objective lens group satisfy: 33.30≤f3 / F1≤40.00; the central curvature radius R31 of the image side surface of the third lens and the central curvature radius R32 of the object side surface thereof satisfy: -8.15≤(R31+R32) / (R31-R32)≤-0.13; the thickness d3 of the third lens along the optical axis direction satisfies: 0.01≤d3 / TTL1≤0.09; and / or The focal length f4 of the fourth lens and the focal length F1 of the objective lens group satisfy: 30.17≤f4 / F1≤35.38; the central curvature radius R41 of the image side surface of the fourth lens and the central curvature radius R42 of the object side surface of the fourth lens satisfy: -3.25≤(R41+R42) / (R41-R42)≤-0.11; the thickness d4 of the fourth lens along the optical axis direction satisfies: 0.01≤d4 / TTL1≤0.08; and / or The focal length f5 of the fifth lens and the focal length F1 of the objective lens group satisfy: 33.70≤f5 / F1≤40.22; the central curvature radius R51 of the image side surface of the fifth lens and the central curvature radius R52 of the object side surface thereof satisfy: 0.09≤(R51+R52) / (R51-R52)≤0.10; the thickness d5 of the fifth lens along the optical axis direction satisfies: 0.01≤d5 / TTL1≤0.07; and / or The focal length f6 of the sixth lens and the focal length F1 of the objective lens group satisfy: 35.80≤f6 / F1≤42.10; the central curvature radius R61 of the image side surface of the sixth lens and the central curvature radius R62 of the object side surface thereof satisfy: 0.17≤(R61+R62) / (R61-R62)≤5.03; the thickness d6 of the sixth lens along the optical axis direction satisfies: 0.01≤d6 / TTL1≤0.40; and / or The focal length f7 of the seventh lens and the focal length F1 of the objective lens group satisfy: 38.81≤f7 / F1≤45.17; the central curvature radius R71 of the image side surface of the seventh lens and the central curvature radius R72 of the object side surface thereof satisfy: 1.25≤(R71+R72) / (R71-R72)≤7.36; the thickness d7 of the seventh lens along the optical axis direction satisfies: 0.01≤d7 / TTL1≤0.12; and / or The focal length f8 of the eighth lens and the focal length F1 of the objective lens group satisfy: 306.10≤f8 / F1≤314.62; the central curvature radius R81 of the image side surface of the eighth lens and the central curvature radius R82 of the object side surface of the eighth lens satisfy: 10.18≤(R81+R82) / (R81-R82)≤29.91; the thickness d8 of the eighth lens along the optical axis direction satisfies: 0.01≤d8 / TTL1≤0.08; and / or The focal length f9 of the ninth lens and the focal length F1 of the objective lens group satisfy: 25.35≤f9 / F1≤31.20; the central curvature radius R91 of the image side surface of the ninth lens and the central curvature radius R92 of the object side surface thereof satisfy: -80.53≤(R91+R92) / (R91-R92)≤-20.10; the thickness d9 of the ninth lens along the optical axis direction satisfies: 0.01≤d9 / TTL1≤0.05; and / or The focal length f10 of the tenth lens and the focal length F1 of the objective lens group satisfy: -3.18≤f10 / F1≤-1.47; the central curvature radius R101 of the image side surface of the tenth lens and the central curvature radius R102 of the object side surface thereof satisfy: 0.01≤(R101+R102) / (R101-R102)≤0.44; the thickness d10 of the tenth lens along the optical axis direction satisfies: 0.01≤d10 / TTL1≤0.

03.

4. The microscopic imaging system according to claim 2, characterized in that: Along the optical axis from the object plane to the imaging plane, the eyepiece assembly includes: The eleventh lens has positive refractive power, and its object side surface is convex and its image side surface is concave; A first cemented lens group having positive optical power; a second cemented lens group having positive optical power; and The sixteenth lens having negative optical power has a convex object-side surface and a concave image-side surface.

5. The microscopic imaging system according to claim 4, characterized in that: The focal length f11 of the eleventh lens and the focal length F2 of the eyepiece assembly satisfy: -2.76≤f11 / F2≤-1.31; the central curvature radius L1 of the image side surface of the eleventh lens and the central curvature radius L2 of the object side surface of the eleventh lens satisfy: 0.62≤L1 / L2≤1.83; the thickness d11 of the eleventh lens along the optical axis direction satisfies: 0.001≤d11 / TTL2≤0.004; and / or The focal length f16 of the sixteenth lens and the focal length F2 of the eyepiece group satisfy: -0.83≤f16 / F2≤-0.29; the central curvature radius L3 of the image side surface of the sixteenth lens and the central curvature radius L4 of the object side surface satisfy: 1.68≤L3 / L4≤2.73; the thickness d16 of the sixteenth lens along the optical axis direction satisfies: 0.05≤d16 / TTL2≤0.

09.

6. The microscopic imaging system according to claim 4, characterized in that: Along the direction from the object plane to the imaging plane of the optical axis, the first cemented lens group includes a twelfth lens and a thirteenth lens cemented to each other, the twelfth lens has positive focal power, and the object side surface of the twelfth lens is convex, and the image side surface is convex, the thirteenth lens has negative focal power, and the object side surface of the thirteenth lens is concave, and the image side surface is convex; and / or Along the direction from the object plane to the imaging plane of the optical axis, the second cemented lens group includes a fourteenth lens and a fifteenth lens cemented to each other, the fourteenth lens has negative optical power, and the object side surface of the fourteenth lens is convex, and the image side surface is concave, and the fifteenth lens has positive optical power, and the object side surface of the fifteenth lens is convex, and the image side surface is convex.

7. The microscopic imaging system according to claim 6, characterized in that: The focal length f12 of the twelfth lens and the focal length F2 of the eyepiece assembly satisfy: -10.15≤f12 / F2≤-9.05; the central curvature radius L5 of the image side surface of the twelfth lens and the central curvature radius L6 of the object side surface of the twelfth lens satisfy: -2.29≤L5 / L6≤-0.35; the thickness d12 of the twelfth lens along the optical axis direction satisfies: 0.08≤d12 / TTL2≤0.20; and / or The focal length f13 of the thirteenth lens and the focal length F2 of the eyepiece assembly satisfy: 5.80≤f13 / F2≤6.64; the central curvature radius L7 of the image side surface of the thirteenth lens and the central curvature radius L8 of the object side surface of the thirteenth lens satisfy: 0.00≤L7 / L8≤0.98; the thickness d13 of the thirteenth lens along the optical axis direction satisfies: 0.02≤d13 / TTL2≤0.06; and / or The focal length f14 of the fourteenth lens and the focal length F2 of the eyepiece assembly satisfy: 1.34≤f14 / F2≤2.28; the central curvature radius L9 of the image side surface of the fourteenth lens and the central curvature radius L10 of the object side surface of the fourteenth lens satisfy: 0.55≤L9 / L10≤1.20; the thickness d14 of the fourteenth lens along the optical axis direction satisfies: 0.03≤d14 / TLT2≤0.07; and / or The focal length f15 of the fifteenth lens and the focal length F2 of the eyepiece group satisfy: 58.17≤f15 / F2≤59.66; the central curvature radius L11 of the image side surface of the fifteenth lens and the central curvature radius L12 of the object side surface of the fifteenth lens satisfy: -1.93≤L11 / L12≤-0.45; the thickness d15 of the fifteenth lens along the optical axis direction satisfies: 0.04≤d15 / TLT2≤0.

08.

8. The microscopic imaging system according to claim 4, characterized in that: The objective lens group further includes a first aperture, and the eyepiece lens group further includes a second aperture. Along the direction of the optical axis from the object plane to the imaging plane, the first aperture is arranged on the side of the tenth lens facing the imaging plane, and the second aperture is arranged on the side of the eleventh lens facing the object plane. The diameter a of the first aperture and the diameter b of the second aperture satisfy: ba ≥ 4.30; and / or The numerical aperture NA of the objective lens group and the focal length F1 of the objective lens group satisfy: 1.04≤NA*F1≤2.

14.

9. The microscopic imaging system according to claim 4, characterized in that: The first lens to the sixteenth lens are all spherical lenses.

10. A laser precision processing device, characterized in that: Comprising a microscopic imaging system as described in any one of claims 1-9.

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