Optical systems and microscopes

Abstract

Embodiments of the present disclosure provide an optical system and a microscope. The optical system includes a microscope objective and a tube lens arranged in sequence along the optical axis from the object side to the image side. The microscope objective includes a first lens group, a second lens group, an aperture, and a third lens group arranged in sequence along the optical axis. The first lens group has positive focal power and is at least used to correct spherical aberration, astigmatism, and axial chromatic aberration. The first lens group includes a first cemented lens, a third lens, and a second cemented lens. The second lens group has positive focal power and is at least used to correct coma and distortion. The second lens group includes a sixth lens and a third cemented lens. The third lens group has positive focal power and is at least used to correct field curvature and vertical chromatic aberration. The third lens group includes a fourth cemented lens, a thirteenth lens, a fourteenth lens, and a fifteenth lens. The tube lens has positive focal power. The tube lens includes a fifth cemented lens, a sixth cemented lens, and a twenty-first lens arranged in sequence along the optical axis.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to the field of optical imaging technology, and more particularly to an optical system and a microscope. Background Art

[0002] With the application of compound semiconductor quantity detection and life science fluorescence detection in scenarios such as defect diversity, product type complexity, weak light emission, and high detection efficiency, higher requirements are placed on microscopic imaging optical systems. To meet these application requirements of optical systems, optical systems need to have a larger field of view. A large field of view can significantly increase the imaging field of the optical system. For samples of a fixed area, a larger imaging range means more light flux and fewer detection times, thereby improving overall detection efficiency. Summary of the Invention

[0003] In a first aspect of the present disclosure, an optical system is provided. The optical system includes: a microscope objective lens and a tube lens arranged in sequence along the optical axis from the object side to the image side, wherein the microscope objective lens includes a first lens group, a second lens group, an aperture, and a third lens group arranged in sequence along the optical axis; the first lens group has positive focal length and is at least used to correct spherical aberration, astigmatism, and axial chromatic aberration, the first lens group includes a first cemented lens, a third lens, and a second cemented lens, the first cemented lens includes a first lens and a second lens cemented together, and the second cemented lens includes a fourth lens and a fifth lens cemented together; the second lens group has positive focal length and is at least used to correct coma and distortion, the second lens group includes a sixth lens and a third cemented lens, the third cemented lens includes a seventh lens, an eighth lens, and a ninth lens cemented together in sequence. mirror; the third lens group has positive focal power and is at least used to correct field curvature and vertical chromatic aberration, the third lens group includes a fourth cemented lens, a thirteenth lens, a fourteenth lens and a fifteenth lens, the fourth cemented lens includes a tenth lens, an eleventh lens and a twelfth lens cemented in sequence; the aperture is arranged between the third cemented lens and the fourth cemented lens to correct chromatic aberration by being placed on both sides of the aperture via the third cemented lens and the fourth cemented lens; the tube lens has positive focal power, the tube lens includes a fifth cemented lens, a sixth cemented lens and a twenty-first lens arranged in sequence along the optical axis, the fifth cemented lens includes a sixteenth lens and a seventeenth lens cemented to each other, and the sixth cemented lens includes an eighteenth lens, a nineteenth lens and a twentieth lens cemented in sequence.

[0004] In some embodiments, the microscope objective is an infinite conjugate objective, at least for imaging objects on the object side to infinity, and the tube lens is an infinite focusing lens, at least for imaging objects at infinity onto a detector on the image side.

[0005] In some embodiments, the focal length of the tube lens is 200 mm.

[0006] In some embodiments, the focal lengths of the first lens group, the second lens group, and the third lens group satisfy the following: 1.0<|f1 / f|<2.0, 1.5<|f2 / f|<2.5, and 7.0<|f3 / f|<8.0, where f is the total focal length of the microscope objective, f1 is the focal length of the first lens group, f2 is the focal length of the second lens group, and f3 is the focal length of the third lens group.

[0007] In some embodiments, the object side of the first lens is concave, and the image side of the first lens is concave; the object side of the second lens is convex, and the image side of the second lens is convex; the object side of the third lens is convex, and the image side of the third lens is convex; the object side of the fourth lens is concave, and the image side of the fourth lens is concave; the object side of the fifth lens is convex, and the image side of the fifth lens is flat; the object side of the sixth lens is concave, and the image side of the sixth lens is convex; the object side of the seventh lens is convex, and the image side of the seventh lens is convex; the object side of the eighth lens is concave, and the image side of the eighth lens is concave. The image side of the eighth lens is concave; the object side of the ninth lens is convex, and the image side of the ninth lens is convex; the object side of the tenth lens is convex, and the image side of the tenth lens is concave; the object side of the eleventh lens is convex, and the image side of the eleventh lens is convex; the object side of the twelfth lens is concave, and the image side of the twelfth lens is concave; the object side of the thirteenth lens is concave, and the image side of the thirteenth lens is convex; the object side of the fourteenth lens is concave, and the image side of the fourteenth lens is convex; the object side of the fifteenth lens is convex, and the image side of the fifteenth lens is convex.

[0008] In some embodiments, the first lens has negative optical power and a focal length in the range of -410mm to -400mm; the second lens has positive optical power and a focal length in the range of 20mm to 30mm; the third lens has positive optical power and a focal length in the range of 40mm to 50mm; the fourth lens has negative optical power and a focal length in the range of -40mm to -30mm; the fifth lens has positive optical power and a focal length in the range of 160mm to 170mm; the sixth lens has positive optical power and a focal length in the range of 40mm to 50mm; the seventh lens has positive optical power and a focal length in the range of 110mm to 120mm; the eighth lens has negative optical power and a focal length in the range of The ninth lens has negative optical power and a focal length in the range of -120mm to -110mm; the tenth lens has positive optical power and a focal length in the range of 20mm to 30mm; the eleventh lens has negative optical power and a focal length in the range of -20mm to -10mm; the twelfth lens has negative optical power and a focal length in the range of -25mm to -15mm; the thirteenth lens has negative optical power and a focal length in the range of -20mm to -10mm; the fourteenth lens has positive optical power and a focal length in the range of 55mm to 65mm; the fifteenth lens has positive optical power and a focal length in the range of 110mm to 120mm.

[0009] In some embodiments, the focal lengths of the first lens group, the second lens group, and the third lens group satisfy the following conditions: 0.5<|f1 / f|<1.5, 1.3<|f2 / f|<2.3, and 1.0<|f3 / f|<2.0, where f is the total focal length of the microscope objective, f1 is the focal length of the first lens group, f2 is the focal length of the second lens group, and f3 is the focal length of the third lens group.

[0010] In some embodiments, the object side of the first lens is concave, and the image side of the first lens is concave; the object side of the second lens is convex, and the image side of the second lens is convex; the object side of the third lens is convex, and the image side of the third lens is convex; the object side of the fourth lens is concave, and the image side of the fourth lens is concave; the object side of the fifth lens is convex, and the image side of the fifth lens is flat; the object side of the sixth lens is flat, and the image side of the sixth lens is convex; the object side of the seventh lens is convex, and the image side of the seventh lens is convex; the object side of the eighth lens is concave, and the image side of the eighth lens is concave. The image side of the eighth lens is concave; the object side of the ninth lens is convex, and the image side of the ninth lens is convex; the object side of the tenth lens is convex, and the image side of the tenth lens is concave; the object side of the eleventh lens is convex, and the image side of the eleventh lens is convex; the object side of the twelfth lens is concave, and the image side of the twelfth lens is flat; the object side of the thirteenth lens is concave, and the image side of the thirteenth lens is convex; the object side of the fourteenth lens is concave, and the image side of the fourteenth lens is convex; the object side of the fifteenth lens is convex, and the image side of the fifteenth lens is convex.

[0011] In some embodiments, the first lens has negative optical power and a focal length in the range of -60mm to -50mm; the second lens has positive optical power and a focal length in the range of 20mm to 30mm; the third lens has positive optical power and a focal length in the range of 30mm to 40mm; the fourth lens has negative optical power and a focal length in the range of -30mm to -20mm; the fifth lens has positive optical power and a focal length in the range of 300mm to 310mm; the sixth lens has positive optical power and a focal length in the range of 45mm to 55mm; the seventh lens has positive optical power and a focal length in the range of 190mm to 200mm; the eighth lens has negative optical power and a focal length in the range of The ninth lens has negative optical power and a focal length in the range of -85mm to -75mm; the tenth lens has positive optical power and a focal length in the range of 20mm to 30mm; the eleventh lens has negative optical power and a focal length in the range of -20mm to -10mm; the twelfth lens has negative optical power and a focal length in the range of -45mm to -35mm; the thirteenth lens has negative optical power and a focal length in the range of -20mm to -10mm; the fourteenth lens has positive optical power and a focal length in the range of 45mm to 55mm; and the fifteenth lens has positive optical power and a focal length in the range of 105mm to 115mm.

[0012] In some embodiments, the focal lengths of the first lens group, the second lens group, and the third lens group satisfy the following: 0.9<|f1 / f|<1.9, 5.5<|f2 / f|<6.5, and 18.0<|f3 / f|<19.0, where f is the total focal length of the microscope objective, f1 is the focal length of the first lens group, f2 is the focal length of the second lens group, and f3 is the focal length of the third lens group.

[0013] In some embodiments, the object side of the first lens is concave, and the image side of the first lens is convex; the object side of the second lens is concave, and the image side of the second lens is convex; the object side of the third lens is convex, and the image side of the third lens is concave; the object side of the fourth lens is convex, and the image side of the fourth lens is concave; the object side of the fifth lens is convex, and the image side of the fifth lens is concave; the object side of the sixth lens is concave, and the image side of the sixth lens is convex; the object side of the seventh lens is convex, and the image side of the seventh lens is convex; the object side of the eighth lens is concave, and the image side of the eighth lens is concave. The image side of the eighth lens is concave; the object side of the ninth lens is convex, and the image side of the ninth lens is convex; the object side of the tenth lens is convex, and the image side of the tenth lens is concave; the object side of the eleventh lens is convex, and the image side of the eleventh lens is convex; the object side of the twelfth lens is concave, and the image side of the twelfth lens is concave; the object side of the thirteenth lens is concave, and the image side of the thirteenth lens is convex; the object side of the fourteenth lens is concave, and the image side of the fourteenth lens is convex; the object side of the fifteenth lens is convex, and the image side of the fifteenth lens is convex.

[0014] In some embodiments, the first lens has negative optical power and a focal length in the range of -40 mm to -30 mm; the second lens has positive optical power and a focal length in the range of 10 mm to 20 mm; the third lens has positive optical power and a focal length in the range of 30 mm to 40 mm; the fourth lens has positive optical power and a focal length in the range of 30 mm to 40 mm; the fifth lens has negative optical power and a focal length in the range of -50 mm to -40 mm; the sixth lens has positive optical power and a focal length in the range of 60 mm to 70 mm; the seventh lens has positive optical power and a focal length in the range of 100 mm to 110 mm; the eighth lens has negative optical power and a focal length in the range of The ninth lens has negative optical power and a focal length in the range of -120mm to -110mm; the tenth lens has positive optical power and a focal length in the range of 10mm to 20mm; the eleventh lens has negative optical power and a focal length in the range of -15mm to -5mm; the twelfth lens has negative optical power and a focal length in the range of -15mm to -5mm; the thirteenth lens has negative optical power and a focal length in the range of -15mm to -5mm; the fourteenth lens has positive optical power and a focal length in the range of 55mm to 65mm; the fifteenth lens has positive optical power and a focal length in the range of 90mm to 100mm.

[0015] In some embodiments, the object side of the sixteenth lens is convex, and the image side of the sixteenth lens is convex; the object side of the seventeenth lens is concave, and the image side of the seventeenth lens is convex; the object side of the eighteenth lens is convex, and the image side of the eighteenth lens is concave; the object side of the nineteenth lens is convex, and the image side of the nineteenth lens is concave; the object side of the twentieth lens is convex, and the image side of the twentieth lens is flat; the object side of the twenty-first lens is flat, and the image side of the twenty-first lens is concave.

[0016] In some embodiments, the sixteenth lens has negative optical power and a focal length in the range of -310 mm to -300 mm; the seventeenth lens has positive optical power and a focal length in the range of 350 mm to 360 mm; the eighteenth lens has positive optical power and a focal length in the range of 80 mm to 90 mm; the nineteenth lens has positive optical power and a focal length in the range of 1340 mm to 1350 mm; the twentieth lens has positive optical power and a focal length in the range of 5790 mm to 5800 mm; and the twenty-first lens has negative optical power and a focal length in the range of -70 mm to -60 mm.

[0017] In some embodiments, the diameter of the aperture comprises one of 12 mm and 8 mm.

[0018] In some embodiments, the operating wavelength band of the optical system includes 400 nm-700 nm.

[0019] In some embodiments, a distance between the object-side surface of the first lens and the object is in a range of 7.0 mm to 13.0 mm.

[0020] In some embodiments, the front entrance pupil distance of the tube lens is in the range of 100.0 mm to 210.0 mm, and the back working distance of the tube lens is in the range of 150.0 mm to 151.0 mm.

[0021] In some embodiments, 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, the thirteenth lens, the fourteenth lens, the fifteenth lens, the sixteenth lens, the seventeenth lens, the eighteenth lens, the nineteenth lens, the twentieth lens, and the twenty-first lens are standard spherical lenses.

[0022] In a second aspect of the present disclosure, a microscope is provided, comprising the optical system of the first aspect of the present disclosure.

[0023] In some embodiments, the microscope further comprises a first optical element arranged between the microscope objective and the tube lens, and / or a second optical element arranged between the tube lens and the image-side detector.

[0024] In some embodiments, the first optical element comprises at least one of a dichroic mirror, a filter, and a prism, and the second optical element comprises at least one of a beam splitter and a filter.

[0025] In an embodiment of the present disclosure, an optical system includes a microscope objective and a tube lens arranged sequentially along the optical axis from the object side to the image side. The microscope objective includes a first lens group, a second lens group, an aperture, and a third lens group arranged sequentially along the optical axis. The first lens group has positive focal power and is used to correct at least spherical aberration, astigmatism, and axial chromatic aberration. The first lens group includes a first cemented lens, a third lens, and a second cemented lens. The first cemented lens includes a first lens and a second lens cemented together. The second cemented lens includes a fourth lens and a fifth lens cemented together. The second lens group has positive focal power and is used to correct at least coma and distortion. The second lens group includes a sixth lens and a third cemented lens. The third cemented lens includes a seventh lens, an eighth lens, and a ninth lens cemented together in sequence. The third lens group has positive focal power and is used to correct at least field curvature and vertical chromatic aberration. The third lens group includes a fourth cemented lens, a thirteenth lens, a fourteenth lens, and a fifteenth lens. The fourth cemented lens includes a tenth lens, an eleventh lens, and a twelfth lens cemented together in sequence. The aperture is arranged between the third and fourth cemented lenses. Chromatic aberration can be corrected by placing the third and fourth cemented lenses on either side of the aperture. The tube lens has positive optical power. It includes a fifth, sixth, and twenty-first cemented lenses arranged in sequence along the optical axis. The fifth cemented lens includes a sixteenth and seventeenth cemented lenses. The sixth cemented lens includes an eighteenth, nineteenth, and twentieth lens cemented in that order.

[0026] With this arrangement, the microscope objective of the optical system contains three groups of positive optical power lenses. The first lens group can correct spherical aberration, astigmatism and axial chromatic aberration, the second lens group can optimize coma and distortion, and the third lens group can correct field curvature and vertical chromatic aberration. Multiple groups of cemented lenses can effectively reduce chromatic aberration and aberration. The tube lens has positive optical power and contains two groups of cemented lenses and a single lens, which can further improve the imaging quality. Through the coordinated correction of multiple lens groups, the field of view can be expanded while maintaining high resolution and image clarity. A larger field of view can reduce the number of scans, thereby improving detection efficiency.

[0027] It should be understood that the content described in this content section is not intended to limit the key features or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, wherein:

[0029] Figure 1Schematic diagram of the optical structure of a microscope objective lens with a focal length of 20 mm according to an embodiment of the present disclosure is shown;

[0030] Figure 2 shows a modulation transfer function curve of a reverse-engineered microscope objective lens with a focal length of 20 mm according to an embodiment of the present disclosure;

[0031] Figure 3 shows the field curvature and distortion diagram of the reverse-engineered microscope objective lens with a focal length of 20 mm according to an embodiment of the present disclosure;

[0032] Figure 4 A reverse-engineered 0.707 pupil color focal shift diagram of a microscope objective lens with a focal length of 20 mm according to an embodiment of the present disclosure is shown;

[0033] Figure 5 Schematic diagram of the optical structure of a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure is shown;

[0034] Figure 6 shows a modulation transfer function graph of a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure;

[0035] Figure 7 shows a diagram of field curvature and distortion of a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure;

[0036] Figure 8 A schematic diagram of the optical structure of a microscopic imaging optical system with a magnification of 10x is shown, in which a microscope objective lens with a focal length of 20 mm and a tube lens with a focal length of 200 mm are combined in accordance with an embodiment of the present disclosure;

[0037] Figure 9 A modulation transfer function curve diagram of a microscope imaging optical system with a magnification of 10x formed by combining a microscope objective lens with a focal length of 20 mm and a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure is shown;

[0038] Figure 10 Schematic diagram of the optical structure of a microscope objective lens with a focal length of 40 mm according to an embodiment of the present disclosure is shown;

[0039] Figure 11 shows a modulation transfer function curve of a reverse-engineered microscope objective lens with a focal length of 40 mm according to an embodiment of the present disclosure;

[0040] Figure 12 shows the field curvature and distortion diagram of the reverse-engineered microscope objective lens with a focal length of 40 mm according to an embodiment of the present disclosure;

[0041] Figure 13 A reverse-engineered 0.707 pupil color focal shift diagram of a microscope objective lens with a focal length of 40 mm according to an embodiment of the present disclosure is shown;

[0042] Figure 14 A schematic diagram of the optical structure of a microscopic imaging optical system with a magnification of 5x is shown, in which a microscope objective lens with a focal length of 40 mm and a tube lens with a focal length of 200 mm are combined in accordance with an embodiment of the present disclosure;

[0043] Figure 15 A modulation transfer function curve diagram of a microscopic imaging optical system with a magnification of 5x formed by combining a microscope objective lens with a focal length of 40 mm and a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure is shown;

[0044] Figure 16 Schematic diagram of the optical structure of a microscope objective lens with a focal length of 10 mm according to an embodiment of the present disclosure is shown;

[0045] Figure 17 shows a modulation transfer function curve of a reverse-engineered microscope objective lens with a focal length of 10 mm according to an embodiment of the present disclosure;

[0046] Figure 18 shows the field curvature and distortion diagram of the reverse-engineered microscope objective lens with a focal length of 10 mm according to an embodiment of the present disclosure;

[0047] Figure 19 A reverse-engineered 0.707 pupil color focal shift diagram of a microscope objective lens with a focal length of 10 mm according to an embodiment of the present disclosure is shown;

[0048] Figure 20 A schematic diagram showing the optical structure of a microscopic imaging optical system with a magnification of 20x formed by combining a microscope objective lens with a focal length of 10 mm and a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure; and

[0049] Figure 21 A modulation transfer function curve of a microscope imaging optical system with a magnification of 20× is shown, which is formed by combining a microscope objective lens with a focal length of 10 mm and a tube lens with a focal length of 200 mm according to an embodiment of the present disclosure.

[0050] Description of reference numerals:

[0051] Obj, microscope objective; TL, tube lens; STOP, aperture;

[0052] G1, first lens group; G2, second lens group; G3, third lens group;

[0053] B1, first cemented lens; B2, second cemented lens; B3, third cemented lens; B4, fourth cemented lens; B5, fifth cemented lens; B6, sixth cemented lens;

[0054] 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;

[0055] L13, the thirteenth lens; L14, the fourteenth lens; L15, the fifteenth lens; L16, the sixteenth lens; L17, the seventeenth lens; L18, the eighteenth lens; L19, the nineteenth lens; L20, the twentieth lens; L21, the twenty-first lens. DETAILED DESCRIPTION

[0056] The preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0057] As used herein, the term "including" and its variations represent open inclusion, i.e., "including but not limited to." Unless otherwise stated, the term "or" means "and / or." The term "based on" means "based at least in part on." The terms "one example embodiment" and "an embodiment" mean "at least one example embodiment." The term "another embodiment" means "at least one additional embodiment." The terms "first," "second," etc. may refer to different or identical objects.

[0058] In conventional infinite conjugate microscopy optical systems, the field of view is generally low and cannot meet the needs of current semiconductor applications, thus limiting the efficiency of semiconductor quantity detection.

[0059] Embodiments of the present disclosure provide an optical system and a microscope. The optical system includes a microscope objective and a tube lens arranged sequentially along the optical axis from the object side to the image side. The microscope objective includes a first lens group, a second lens group, an aperture, and a third lens group arranged sequentially along the optical axis. The first lens group has positive focal power and is used to correct at least spherical aberration, astigmatism, and axial chromatic aberration. The first lens group includes a first cemented lens, a third lens, and a second cemented lens. The first cemented lens includes a first lens and a second lens cemented together. The second cemented lens includes a fourth lens and a fifth lens cemented together. The second lens group has positive focal power and is used to correct at least coma and distortion. The second lens group includes a sixth lens and a third cemented lens. The third cemented lens includes a seventh lens, an eighth lens, and a ninth lens cemented together in sequence. The third lens group has positive focal power and is used to correct at least field curvature and vertical chromatic aberration. The third lens group includes a fourth cemented lens, a thirteenth lens, a fourteenth lens, and a fifteenth lens. The fourth cemented lens includes a tenth lens, an eleventh lens, and a twelfth lens cemented together in sequence. The aperture is arranged between the third and fourth cemented lenses. Chromatic aberration can be corrected by placing the third and fourth cemented lenses on either side of the aperture. The tube lens has positive optical power. The tube lens has positive optical power. The tube lens includes a fifth, sixth, and twenty-first lenses arranged in sequence along the optical axis. The fifth cemented lens includes a sixteenth and seventeenth lenses cemented together. The sixth cemented lens includes an eighteenth, nineteenth, and twentieth lenses cemented together in that order.

[0060] With this arrangement, the microscope objective of the optical system contains three groups of positive optical power lens groups. The first lens group can correct spherical aberration, astigmatism and axial chromatic aberration, the second lens group can optimize coma and distortion, the third lens group can correct field curvature and vertical axis chromatic aberration, and multiple groups of cemented lenses can effectively reduce chromatic aberration and aberration. The tube lens has positive optical power and contains two groups of cemented lenses and a single lens, which can further improve the imaging quality. Through the coordinated correction of multiple lens groups, the field of view can be expanded while maintaining high resolution and imaging clarity. A larger field of view number can reduce the number of scans, thereby improving detection efficiency. The following will be combined with Figures 1 to 21 To describe the principles of the present disclosure in detail.

[0061] like Figures 1 to 8 As shown in Figure 1, the optical system consists of a microscope objective lens Obj and a tube lens TL, arranged sequentially along the optical axis from the object to the image. The microscope objective lens Obj focuses the light from the object and preliminarily corrects various aberrations, while the tube lens TL optimizes the optical path, ultimately forming a high-quality image. This optical system can be applied to microscopic inspection scenarios requiring high resolution and a large field of view, such as biomedical research, materials analysis, and semiconductor testing.

[0062] like Figure 1As shown, the microscope objective Obj consists of a first lens group G1, a second lens group G2, and a third lens group G3 arranged in sequence along the optical axis. Each lens group is responsible for a specific aberration correction task, which can effectively control various optical aberrations in complex imaging environments, thereby achieving high-resolution and large field of view imaging.

[0063] like Figure 1 As shown, the first lens group G1 is located at the front end of the microscope objective Obj and has positive optical power. The first lens group G1 can correct spherical aberration, astigmatism and axial chromatic aberration. The first lens group G1 includes a first cemented lens B1, a third lens L3 and a second cemented lens B2. The first cemented lens B1 is formed by cementing the first lens L1 and the second lens L2, and the second cemented lens B2 is formed by cementing the fourth lens L4 and the fifth lens L5. By closely combining lenses with different refractive indices and dispersion characteristics, axial chromatic aberration can be reduced while optimizing spherical aberration and astigmatism. As a single lens, the third lens L3 can assist in adjusting the convergence of the optical path, thereby providing suitable optical conditions for subsequent lens groups. The first lens group G1 can ensure that the light has smaller initial aberrations when entering the subsequent lens groups.

[0064] like Figure 1 As shown, the second lens group G2 also has positive optical power and can correct coma and distortion. The second lens group G2 includes the sixth lens L6 and the third cemented lens B3. The third cemented lens B3 is formed by cementing the seventh lens L7, the eighth lens L8 and the ninth lens L9 in sequence. Coma manifests as an asymmetric light spot, which will cause a tailing phenomenon when imaging a point light source, while distortion will cause the geometric shape of the image edge to be distorted, affecting the imaging quality at the edge of the field of view. Through the composite structure of the single lens of the sixth lens L6 and the third cemented lens B3, the second lens group G2 can control the propagation path of light at different field of view angles, thereby effectively suppressing coma and distortion. The second lens group G2 can ensure that the imaging quality at the center of the field of view can be extended to the edge area, providing support for large field of view imaging.

[0065] like Figure 1As shown, the third lens group G3, located at the end of microscope objective Obj, has positive refractive power. The third lens group G3 is used to correct for field curvature and vertical chromatic aberration. The third lens group G3 comprises the fourth cemented lens B4, the thirteenth lens L13, the fourteenth lens L14, and the fifteenth lens L15. The fourth cemented lens B4 is formed by cementing the tenth lens L10, the eleventh lens L11, and the twelfth lens L12 in this order. Field curvature can cause the image plane to deviate from the ideal plane, affecting sharpness across the entire field of view, while vertical chromatic aberration manifests as lateral separation of light of different wavelengths at the edges of the field of view. The fourth cemented lens B4, through its multi-element combination, further reduces chromatic aberration. It also works with the subsequent single lenses (the thirteenth lens L13 through the fifteenth lens L15) to adjust the focusing characteristics of light, correct field curvature, and ensure flatness across the entire field of view. In this way, the third lens group G3 enables the optical system to maintain uniform imaging quality across a wide field of view.

[0066] In some embodiments, as Figure 1 、 Figure 10 and Figure 16 As shown, the optical system further includes a stop STOP disposed between the third cemented lens B3 and the fourth cemented lens B4. In this way, chromatic aberration can be corrected by placing the third cemented lens and the fourth cemented lens on both sides of the stop.

[0067] like Figure 5 As shown, the tube lens TL is located after the microscope objective lens Obj and has positive optical power. The tube lens TL can further magnify the intermediate image formed by the microscope objective lens Obj and ultimately project it onto the imaging plane. The tube lens TL includes a fifth cemented lens B5, a sixth cemented lens B6, and a twenty-first lens L21. The fifth cemented lens B5 is formed by cementing the sixteenth lens L16 and the seventeenth lens L17, and the sixth cemented lens B6 is formed by cementing the eighteenth lens L18, the nineteenth lens L19, and the twentieth lens L20 in sequence. Cemented lenses can further reduce chromatic aberration. As a single lens, the twenty-first lens L21 can adjust the convergence of the optical path to ensure the clarity and contrast of the final image. The tube lens TL works in conjunction with the microscope objective lens Obj to optimize the propagation path of light, thereby improving the imaging quality in the edge area under a larger field of view.

[0068] In this way, the microscope objective Obj of the optical system contains three groups of positive focal power lenses, each group is optimized for specific aberrations. The first lens group G1 corrects spherical aberration, astigmatism and axial chromatic aberration through the first cemented lens B1, the third lens L3 and the second cemented lens B2, providing a high-quality optical foundation for the subsequent optical path. The second lens group G2 can optimize coma and distortion through the sixth lens L6 and the third cemented lens B3 to ensure the accurate geometry of the edge of the field of view. The third lens group G3 corrects field curvature and vertical chromatic aberration through the fourth cemented lens B4 and a single lens, which can maintain the flatness and color consistency of the entire field of view. Multiple groups of cemented lenses can reduce chromatic aberration and aberration, thereby improving the clarity and resolution of the image.

[0069] Secondly, the tube lens TL has positive optical power. The combination of the fifth cemented lens B5, the sixth cemented lens B6, and the twenty-first lens L21 improves image quality. The cemented lens suppresses chromatic aberration, while the singlet lens optimizes the convergence of the optical path, ensuring high contrast and sharpness. The synergy between the microscope objective Obj and the tube lens TL, through the precise correction of the multi-lens group, significantly expands the system's field of view while maintaining high resolution and image clarity.

[0070] In addition, the microscopic imaging optical system images the object-side sample onto the image-side sensor at an appropriate magnification through the transmission of the light field, and can provide a longer working distance of the microscope objective lens Obj, the entrance pupil distance of the tube lens TL, and the back working distance. This allows the microscopic imaging optical system to have a large operability space to add various other optical elements required for various application scenarios, such as oblique lighting, coaxial lighting, autofocus modules, filters, dichroic mirrors, beam splitters, reflectors, prisms, etc. to meet the microscopic imaging needs of the application scenarios.

[0071] Finally, the optical system can provide a large field of view of 45mm, thereby reducing the number of image acquisitions for quantitative detection and improving quantitative detection efficiency.

[0072] As an example, the microscopic imaging optical system of the present disclosure can at least provide microscopic objective lens focal lengths of 10 mm, 20 mm, and 40 mm and a microscopic objective lens parfocal distance of 95 mm.

[0073] In some embodiments, the focal length of the tube lens TL is 200 mm.

[0074] In some embodiments, microscope objective lens Obj is an infinite conjugate objective lens, at least for imaging an object on the object side to infinity, and tube lens TL is an infinite focusing lens, at least for imaging an object at infinity onto an image-side detector. Using this arrangement, microscope objective lenses Obj of different focal lengths combined with a tube lens TL having a focal length of 200 mm can form a microscopic imaging optical system with different magnifications.

[0075] As an example, Figures 1 to 4 As shown, the total focal length f of the microscope objective lens Obj is 20 mm. Here, the focal lengths of the first lens group G1, the second lens group G2, and the third lens group G3 satisfy:

[0076] 1.0<|f1 / f|<2.0, 1.5<|f2 / f|<2.5, 7.0<|f3 / f|<8.0,

[0077] Wherein, f1 is the focal length of the first lens group G1, f2 is the focal length of the second lens group G2, and f3 is the focal length of the third lens group G3.

[0078] In some embodiments, the object-side surface of first lens L1 is concave, and the image side of first lens L1 is concave. The object-side surface of second lens L2 is convex, and the image side of second lens L2 is convex. The object-side surface of third lens L3 is convex, and the image side of third lens L3 is convex. The object-side surface of fourth lens L4 is concave, and the image side of fourth lens L4 is concave. The object-side surface of fifth lens L5 is convex, and the image side of fifth lens L5 is flat. The object-side surface of sixth lens L6 is concave, and the image side of sixth lens L6 is convex. The object-side surface of seventh lens L7 is convex, and the image side of seventh lens L7 is convex. The object-side surface of eighth lens L8 is concave, and the image side of eighth lens L8 is concave. The object-side surface of ninth lens L9 is convex, and the image side of ninth lens L9 is convex. The object-side surface of tenth lens L10 is convex, and the image side of tenth lens L10 is concave. The object-side surface of the eleventh lens L11 is convex, and the image-side surface of the eleventh lens L11 is convex. The object-side surface of the twelfth lens L12 is concave, and the image-side surface of the twelfth lens L12 is concave. The object-side surface of the thirteenth lens L13 is concave, and the image-side surface of the thirteenth lens L13 is convex. The object-side surface of the fourteenth lens L14 is concave, and the image-side surface of the fourteenth lens L14 is convex. The object-side surface of the fifteenth lens L15 is convex, and the image-side surface of the fifteenth lens L15 is convex.

[0079] With this arrangement, the nearly flat object-side and concave image-side surfaces of first lens L1 facilitate initial light collection and reduce spherical aberration. The convex surfaces of second lens L2 and third lens L3 enhance light convergence, optimizing axial chromatic aberration and astigmatism. The concave-convex combination of fourth lens L4 and fifth lens L5 effectively corrects chromatic aberration, while the flat image-side surface of fifth lens L5 stabilizes the optical path. The concave-convex shape of sixth lens L6 helps correct coma. The convex-concave-convex combination of seventh lens L7 through ninth lens L9 optimizes coma and distortion, while the concave surface of eighth lens L8 balances aberrations. The convex-concave shapes of tenth lens L10 through twelfth lens L12 correct field curvature. The concave-convex shapes of thirteenth lens L13 through fourteenth lens L14 improve vertical chromatic aberration. The convex surface and nearly flat image side of fifteenth lens L15 ensure uniform field of view.

[0080] In some embodiments, the first lens L1 has negative optical power and a focal length in the range of -410 mm to -400 mm. The second lens L2 has positive optical power and a focal length in the range of 20 mm to 30 mm. The third lens L3 has positive optical power and a focal length in the range of 40 mm to 50 mm. The fourth lens L4 has negative optical power and a focal length in the range of -40 mm to -30 mm. The fifth lens L5 has positive optical power and a focal length in the range of 160 mm to 170 mm. The sixth lens L6 has positive optical power and a focal length in the range of 40 mm to 50 mm. The seventh lens L7 has positive optical power and a focal length in the range of 110 mm to 120 mm. The eighth lens L8 has negative optical power and a focal length in the range of -55 mm to -45 mm. The ninth lens L9 has negative optical power and a focal length in the range of -120 mm to -110 mm. The tenth lens L10 has positive focal power and a focal length within the range of 20 mm to 30 mm. The eleventh lens L11 has negative focal power and a focal length within the range of -20 mm to -10 mm. The twelfth lens L12 has negative focal power and a focal length within the range of -25 mm to -15 mm. The thirteenth lens L13 has negative focal power and a focal length within the range of -20 mm to -10 mm. The fourteenth lens L14 has positive focal power and a focal length within the range of 55 mm to 65 mm. The fifteenth lens L15 has positive focal power and a focal length within the range of 110 mm to 120 mm.

[0081] As an example, Figures 10 to 15 As shown, the total focal length f of the microscope objective lens Obj is 40 mm. Here, the focal lengths of the first lens group G1, the second lens group G2, and the third lens group G3 satisfy:

[0082] 0.5<|f1 / f|<1.5, 1.3<|f2 / f|<2.3, 1.0<|f3 / f|<2.0,

[0083] Wherein, f1 is the focal length of the first lens group G1, f2 is the focal length of the second lens group G2, and f3 is the focal length of the third lens group G3.

[0084] In some embodiments, the object-side surface of first lens L1 is concave, and the image side of first lens L1 is concave. The object-side surface of second lens L2 is convex, and the image side of second lens L2 is convex. The object-side surface of third lens L3 is convex, and the image side of third lens L3 is convex. The object-side surface of fourth lens L4 is concave, and the image side of fourth lens L4 is concave. The object-side surface of fifth lens L5 is convex, and the image side of fifth lens L5 is flat. The object-side surface of sixth lens L6 is flat, and the image side of sixth lens L6 is convex. The object-side surface of seventh lens L7 is convex, and the image side of seventh lens L7 is convex. The object-side surface of eighth lens L8 is concave, and the image side of eighth lens L8 is concave. The object-side surface of ninth lens L9 is convex, and the image side of ninth lens L9 is convex. The object-side surface of tenth lens L10 is convex, and the image side of tenth lens L10 is concave. The object-side surface of the eleventh lens L11 is convex, and the image-side surface of the eleventh lens L11 is convex. The object-side surface of the twelfth lens L12 is concave, and the image-side surface of the twelfth lens L12 is flat. The object-side surface of the thirteenth lens L13 is concave, and the image-side surface of the thirteenth lens L13 is convex. The object-side surface of the fourteenth lens L14 is concave, and the image-side surface of the fourteenth lens L14 is convex. The object-side surface of the fifteenth lens L15 is convex, and the image-side surface of the fifteenth lens L15 is convex.

[0085] In some embodiments, the first lens L1 has negative optical power and a focal length in the range of -60 mm to -50 mm. The second lens L2 has positive optical power and a focal length in the range of 20 mm to 30 mm. The third lens L3 has positive optical power and a focal length in the range of 30 mm to 40 mm. The fourth lens L4 has negative optical power and a focal length in the range of -30 mm to -20 mm. The fifth lens L5 has positive optical power and a focal length in the range of 300 mm to 310 mm. The sixth lens L6 has positive optical power and a focal length in the range of 45 mm to 55 mm. The seventh lens L7 has positive optical power and a focal length in the range of 190 mm to 200 mm. The eighth lens L8 has negative optical power and a focal length in the range of -70 mm to -60 mm. The ninth lens L9 has negative optical power and a focal length in the range of -85 mm to -75 mm. The tenth lens L10 has positive optical power and a focal length within the range of 20 mm to 30 mm. The eleventh lens L11 has negative optical power and a focal length within the range of -20 mm to -10 mm. The twelfth lens L12 has negative optical power and a focal length within the range of -45 mm to -35 mm. The thirteenth lens L13 has negative optical power and a focal length within the range of -20 mm to -10 mm. The fourteenth lens L14 has positive optical power and a focal length within the range of 45 mm to 55 mm. The fifteenth lens L15 has positive optical power and a focal length within the range of 105 mm to 115 mm.

[0086] As an example, Figures 16 to 21As shown, the total focal length f of the microscope objective lens Obj is 10 mm. Here, the focal lengths of the first lens group G1, the second lens group G2, and the third lens group G3 satisfy:

[0087] 0.9<|f1 / f|<1.9, 5.5<|f2 / f|<6.5, 18.0<|f3 / f|<19.0,

[0088] Wherein, f1 is the focal length of the first lens group G1, f2 is the focal length of the second lens group G2, and f3 is the focal length of the third lens group G3.

[0089] In some embodiments, the object-side surface of first lens L1 is concave, and the image-side surface of first lens L1 is convex. The object-side surface of second lens L2 is concave, and the image-side surface of second lens L2 is convex. The object-side surface of third lens L3 is convex, and the image-side surface of third lens L3 is concave. The object-side surface of fourth lens L4 is convex, and the image-side surface of fourth lens L4 is concave. The object-side surface of fifth lens L5 is convex, and the image-side surface of fifth lens L5 is concave. The object-side surface of sixth lens L6 is concave, and the image-side surface of sixth lens L6 is convex. The object-side surface of seventh lens L7 is convex, and the image-side surface of seventh lens L7 is convex. The object-side surface of eighth lens L8 is concave, and the image-side surface of eighth lens L8 is concave. The object-side surface of ninth lens L9 is convex, and the image-side surface of ninth lens L9 is convex. The object-side surface of tenth lens L10 is convex, and the image-side surface of tenth lens L10 is concave. The object-side surface of the eleventh lens L11 is convex, and the image-side surface of the eleventh lens L11 is convex. The object-side surface of the twelfth lens L12 is concave, and the image-side surface of the twelfth lens L12 is concave. The object-side surface of the thirteenth lens L13 is concave, and the image-side surface of the thirteenth lens L13 is convex. The object-side surface of the fourteenth lens L14 is concave, and the image-side surface of the fourteenth lens L14 is convex. The object-side surface of the fifteenth lens L15 is convex, and the image-side surface of the fifteenth lens L15 is convex.

[0090] In some embodiments, the first lens L1 has negative optical power and a focal length in the range of -40 mm to -30 mm. The second lens L2 has positive optical power and a focal length in the range of 10 mm to 20 mm. The third lens L3 has positive optical power and a focal length in the range of 30 mm to 40 mm. The fourth lens L4 has positive optical power and a focal length in the range of 30 mm to 40 mm. The fifth lens L5 has negative optical power and a focal length in the range of -50 mm to -40 mm. The sixth lens L6 has positive optical power and a focal length in the range of 60 mm to 70 mm. The seventh lens L7 has positive optical power and a focal length in the range of 100 mm to 110 mm. The eighth lens L8 has negative optical power and a focal length in the range of -45 mm to -35 mm. The ninth lens L9 has negative optical power and a focal length in the range of -120 mm to -110 mm. The tenth lens L10 has positive optical power and a focal length within the range of 10 mm to 20 mm. The eleventh lens L11 has negative optical power and a focal length within the range of -15 mm to -5 mm. The twelfth lens L12 has negative optical power and a focal length within the range of -15 mm to -5 mm. The thirteenth lens L13 has negative optical power and a focal length within the range of -15 mm to -5 mm. The fourteenth lens L14 has positive optical power and a focal length within the range of 55 mm to 65 mm. The fifteenth lens L15 has positive optical power and a focal length within the range of 90 mm to 100 mm.

[0091] In some embodiments, as Figures 5 to 9 As shown, the object side surface of the sixteenth lens L16 is convex, and the image side surface of the sixteenth lens L16 is convex. The object side surface of the seventeenth lens L17 is concave, and the image side surface of the seventeenth lens L17 is convex. The object side surface of the eighteenth lens L18 is convex, and the image side surface of the eighteenth lens L18 is concave. The object side surface of the nineteenth lens L19 is convex, and the image side surface of the nineteenth lens L19 is concave. The object side surface of the twentieth lens L20 is convex, and the image side surface of the twentieth lens L20 is flat. The object side surface of the twenty-first lens L21 is flat, and the image side surface of the twenty-first lens L21 is concave.

[0092] In some embodiments, the sixteenth lens L16 has negative optical power and a focal length in the range of -310 mm to -300 mm. The seventeenth lens L17 has positive optical power and a focal length in the range of 350 mm to 360 mm. The eighteenth lens L18 has positive optical power and a focal length in the range of 80 mm to 90 mm. The nineteenth lens L19 has positive optical power and a focal length in the range of 1340 mm to 1350 mm. The twentieth lens L20 has positive optical power and a focal length in the range of 5790 mm to 5800 mm. The twenty-first lens L21 has negative optical power and a focal length in the range of -70 mm to -60 mm.

[0093] In some embodiments, the diameter D of the aperture STOP of microscope objective lens Obj is associated with the numerical aperture NA of microscope objective lens Obj, where NA = D / (2*f), where f is the focal length of microscope objective lens Obj. Different diameters D of the aperture STOP and different focal lengths f of microscope objective lens Obj can determine the size of the numerical aperture NA of microscope objective lens Obj.

[0094] When f is 20 mm, the diameter D of the aperture STOP is 12 mm, and the numerical aperture NA of the microscope objective lens Obj is 0.3.

[0095] When f is 40 mm, the diameter D of the aperture STOP is 12 mm, and the numerical aperture NA of the microscope objective Obj is 0.15.

[0096] When f is 10 mm, the diameter D of the aperture STOP is 8 mm, and the numerical aperture NA of the microscope objective lens Obj is 0.4.

[0097] In some embodiments, the optical system operates in a wavelength band encompassing 400nm to 700nm. This broad wavelength band supports multicolor imaging, enabling simultaneous excitation and detection of multiple fluorescent dyes in fluorescence microscopy, increasing the diversity of biological sample analysis. Furthermore, the visible light band matches human vision, resulting in intuitive imaging results that facilitate direct observation or recording.

[0098] In some embodiments, the magnification M of the optical system is equal to the focal length of the tube lens TL / the total focal length of the microscope objective Obj. The focal length of the tube lens TL is 200 mm, and the focal length of the microscope objective Obj can be at least 20 mm, 40 mm, and 10 mm. Therefore, the optical system can have different magnifications, such as 10x, 5x, and 20x.

[0099] In some embodiments, the distance between the object-side surface of first lens L1 and the object is in a range of 7.0 mm to 13.0 mm. In this way, the long working distance of the microscope objective lens can provide sufficient space for operating and observing thick samples.

[0100] In some embodiments, the front entrance pupil distance of the tube lens TL is in the range of 100.0 mm to 210.0 mm, and the back working distance of the tube lens TL is in the range of 150.0 mm to 151.0 mm. In this way, a large front entrance pupil distance facilitates the addition of other optical elements, such as dichroics, filters, and prisms, in the parallel light segment between the microscope objective Obj and the tube lens TL, as required by actual use. A large back working distance facilitates the addition of required optical elements, such as beam splitters and filters, between the tube lens TL and the image-side detector, as required by actual use.

[0101] In some embodiments, the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, the seventh lens L7, the eighth lens L8, the ninth lens L9, the tenth lens L10, the eleventh lens L11, the twelfth lens L12, the thirteenth lens L13, the fourteenth lens L14, the fifteenth lens L15, the sixteenth lens L16, the seventeenth lens L17, the eighteenth lens L18, the nineteenth lens L19, the twentieth lens L20, and the twenty-first lens L21 are standard spherical lenses. In this way, the manufacturing process of standard spherical lenses is mature, which can ensure high quality and consistency and reduce manufacturing costs. In addition, spherical lenses can provide excellent light focusing capabilities, maintain high resolution and contrast, and ensure image clarity and detail. Through the combination of spherical lenses and the selection of materials, aberrations such as chromatic aberration and spherical aberration can be effectively corrected, thereby improving image quality.

[0102] The present disclosure also provides a microscope comprising any one of the above-mentioned optical systems.

[0103] In some embodiments, the microscope further comprises a first optical element arranged between the microscope objective Obj and the tube lens TL.

[0104] As an example, the first optical element may include a dichroic mirror. A dichroic mirror is a specialized optical element that selectively reflects or transmits light based on wavelength. Its primary function is to separate excitation light from emission light in applications such as fluorescence microscopy. For example, in fluorescence imaging, a dichroic mirror allows short-wavelength excitation light to pass through to illuminate the sample while simultaneously reflecting the long-wavelength fluorescence signal to the tube lens (TL) and detector. This separation improves imaging contrast and reduces background light interference, thereby enhancing the detection accuracy of the fluorescence signal. It is suitable for scenarios such as cell imaging in biomedical research.

[0105] As another example, the first optical element may include a filter. The function of a filter is to selectively transmit light of specific wavelengths and block light of other wavelengths. In microscopic imaging, filters are often used to enhance the contrast and purity of images. For example, in a fluorescence microscope, a bandpass filter can only allow the fluorescence wavelength emitted by the sample to pass through, filtering out excitation light or other stray light, thereby improving signal clarity. In addition, filters can also be used for multispectral imaging to separate light of different wavelengths, which is suitable for material analysis or multicolor labeling research of biological samples.

[0106] As another example, the first optical element may include a prism. The main function of a prism is to change the direction of the optical path or disperse light. For example, in a stereo microscope or a polarization microscope, a prism can be used to adjust the optical path to achieve observation at a specific angle, or to split the light beam into multiple paths to support multi-view imaging. In addition, a dispersion prism can separate light of different wavelengths, which is suitable for spectral analysis or multi-color imaging systems. The addition of a prism enhances the flexibility of the system, making it adaptable to complex optical configurations such as polarization detection or multi-path microscopy.

[0107] In some embodiments, the microscope further comprises a second optical element arranged between the tube lens TL and the image-side detector.

[0108] As an example, the second optical element can include a beamsplitter. A beamsplitter's function is to split an incoming light beam into two or more beams according to a specific ratio or characteristic. For example, in a microscopy system, a beamsplitter can split the beam into two, directing one beam to a primary detector (such as a CCD camera) for imaging and the other to an auxiliary detector (such as a spectrometer) for spectral analysis. This configuration enables simultaneous imaging and spectral measurement and is widely used in multimodal microscopy. Furthermore, beamsplitters can be used for dual-channel imaging, enhancing the system's versatility and improving detection efficiency.

[0109] As another example, the second optical element may include a filter. The function of a filter is to selectively transmit light of specific wavelengths while blocking light of other wavelengths. In microscopic imaging, filters are often used to enhance the contrast and purity of images. For example, in a fluorescence microscope, a bandpass filter allows only the fluorescence wavelengths emitted by the sample to pass through, filtering out excitation light or other stray light, thereby improving signal clarity. Furthermore, filters can be used for multispectral imaging, separating light of different wavelengths, which is suitable for materials analysis or multicolor labeling studies of biological samples.

[0110] The following uses the optical parameter values shown in Tables 1 to 3 and Figures 1 to 21 The optical system of the present invention is described in detail based on the optical structure and experimental data. Figures 1 to 9 The optical structure and test data of the optical system of the first embodiment using the optical parameter values shown in Table 1 are shown. Figures 10 to 15 The optical structure and test data of the optical system of the second embodiment using the optical parameter values shown in Table 2 are shown. Figures 16 to 21 The optical structure and test data of the optical system of the third embodiment using the optical parameter values shown in Table 3 are shown. Figures 1 to 9 The principle of the optical system of the first embodiment of the present disclosure will be described in detail.

[0111] Table 1 shows the optical parameters of the microscope imaging optical system with a magnification of 10 times.

[0112] Table 1

[0113]

[0114] In the first embodiment of the present disclosure, the microscope objective and tube lens use the optical parameters shown in Table 1. The microscope objective has a focal length of 20 mm, a numerical aperture of 0.3, a parfocal distance of 95 mm, and a working distance of 10.00 mm. The tube lens has a focal length of 200 mm, a numerical aperture of 0.0325, a front entrance pupil distance of 100 mm to 210 mm, and a rear working distance of 150.67 mm. The microscope imaging optical system has a magnification of 10x, an operating wavelength range of 400 nm to 700 nm, a field of view of 45 mm, and a total length of 382.490 mm.

[0115] like Figure 2 As shown in the figure, the modulation transfer function of the microscope objective with a focal length of 20 mm is close to the diffraction limit, and the modulus value is greater than 0.4 at 500 lp / mm, indicating excellent imaging quality.

[0116] like Figure 3 As shown in the figure, the sagittal field curvature of the microscope objective with a focal length of 20mm is 6.8μm and the meridional field curvature is 5.7μm, which is much smaller than the focal depth of 6.531μm. This is a flat-field microscope objective, and the field curvature is effectively corrected. The distortion is 0.25%, which is small and effectively corrected.

[0117] like Figure 4 As shown in FIG. 1 , the maximum focal shift variation of the 0.707 pupil of the microscope objective lens with a focal length of 20 mm is 0.5 μm, which is much smaller than 1 / 4 of the focal depth of 1.633 μm. The microscope objective lens can achieve perfect imaging.

[0118] like Figure 6 As shown in the modulation transfer function curve of the 200mm focal length tube lens, it is close to the diffraction limit.

[0119] like Figure 7 As shown in the figure, the sagittal field curvature of the 200mm focal length tube lens is 284.5um, and the meridional field curvature is 3.08um, which is less than the focal depth of 556.20um, and the field curvature is effectively corrected. The distortion is 0.33%, which is small and effectively corrected.

[0120] like Figure 9 As shown in FIG, the modulation transfer function curve of the microscope imaging optical system with a magnification of 10 times can be seen to be close to the diffraction limit.

[0121] The following is a combination of the optical parameter values shown in Table 2 and Figures 10 to 15The principle of the optical system of the second embodiment of the present disclosure is described in detail. The tube lens and the combination of the optical system of the second embodiment Figures 1 to 9 The focal lengths of the tube lenses of the first embodiment are the same. Hereinafter, the optical system consisting of a microscope objective lens with a focal length of 40 mm and a tube lens with a focal length of 200 mm will be mainly described, and the same parts will not be described again.

[0122] Table 2 shows the optical parameters of the microscope imaging optical system with a magnification of 5 times.

[0123] Table 2

[0124]

[0125] In the second embodiment of the present disclosure, the microscope objective and tube lens use the optical parameters shown in Table 2. The microscope objective has a focal length of 40 mm, a numerical aperture of 0.15, a parfocal distance of 95 mm, and a working distance of 11.22 mm. The tube lens has a focal length of 200 mm, a numerical aperture of 0.0325, a front entrance pupil distance of 100 mm to 210 mm, and a rear working distance of 150.67 mm. The microscope imaging optical system has a magnification of 5x, an operating wavelength range of 400 nm to 700 nm, a field of view of 45 mm, and a total length of 381.271 mm.

[0126] like Figure 11 As shown in the figure, the modulation transfer function of the microscope objective with a focal length of 40 mm is close to the diffraction limit, and the modulus value at 220 lp / mm is greater than 0.47, indicating excellent imaging quality.

[0127] like Figure 12 As shown in the figure, the sagittal curvature of field of the 40mm focal length microscope objective is 12.2μm and the meridional curvature of field is 7.4μm, which is much smaller than the focal depth of 26.116μm. This is a flat-field microscope objective, and the field curvature is effectively corrected. The distortion is 0.40%, which is small and effectively corrected.

[0128] like Figure 13 As shown in FIG. 1 , the maximum focal shift variation of the 0.707 pupil of the microscope objective lens with a focal length of 40 mm is 2.64 μm, which is much smaller than 1 / 4 of the focal depth of 6.529 μm. The microscope objective lens can achieve perfect imaging.

[0129] like Figure 15 As shown in FIG, the modulation transfer function curve of the microscope imaging optical system with a magnification of 5 times can be seen to be close to the diffraction limit.

[0130] The following is a combination of the optical parameter values shown in Table 3 and Figures 16 to 21The principle of the optical system of the third embodiment of the present disclosure is described in detail. The tube lens and the combination of the optical system of the third embodiment Figures 1 to 9 The focal lengths of the tube lenses of the first embodiment are the same. Hereinafter, the optical system consisting of a microscope objective lens with a focal length of 10 mm and a tube lens with a focal length of 200 mm will be mainly described, and the same parts will not be described again.

[0131] Table 3 shows the optical parameters of the microscope imaging optical system with a magnification of 20 times.

[0132] Table 3

[0133]

[0134] In the third embodiment of the present disclosure, the lenses of the microscope objective and tube lens adopt the optical parameter values shown in Table 3. The microscopic imaging optical system has a magnification of 20x, an operating wavelength range of 400 nm to 700 nm, a field of view of 45 mm, and a total length of 384.507 mm. The focal length of the microscope objective is 10 mm, the numerical aperture is 0.4, the parfocal distance is 95 mm, and the working distance is 7.984 mm. The focal length of the tube lens is 200 mm, the numerical aperture is 0.0325, the front entrance pupil distance is 100 mm to 210 mm, and the rear working distance is 150.67 mm.

[0135] like Figure 17 As shown in the figure, the modulation transfer function of the microscope objective with a focal length of 10 mm is close to the diffraction limit, and the modulus value is greater than 0.29 at 800 lp / mm, indicating excellent imaging quality.

[0136] like Figure 18 As shown in the figure, the sagittal field curvature of the microscope objective with a focal length of 10mm is 1.1μm, and the meridional field curvature is 1.0μm, which is much smaller than the focal depth of 3.696μm. This is a flat-field microscope objective, and the field curvature is effectively corrected. The distortion is 0.40%, which is small and effectively corrected.

[0137] like Figure 19 As shown in FIG. 1 , the maximum focal shift variation of the 0.707 pupil of the microscope objective lens with a focal length of 10 mm is 0.8251 μm, which is less than 1 / 4 of the focal depth of 0.924 μm. The microscope objective lens can achieve perfect imaging.

[0138] like Figure 21 As shown in FIG, the modulation transfer function curve of the microscope imaging optical system with a magnification of 20 times can be seen to be close to the diffraction limit.

[0139] It can be seen from this that the embodiments of the present disclosure can improve a large-field microscopic imaging optical system, in which the microscopic objective lenses have at least three different focal lengths of 20mm, 40mm and 10mm. The matching tube lens has a focal length of 200mm. Therefore, there are three types of microscopic objective lenses combined with one tube lens to form a microscopic imaging optical system with three different magnifications of 10 times, 5 times and 20 times. The microscopic imaging optical system has a long working distance greater than 8.00mm, a numerical aperture of 0.15 / 0.3 / 0.4, a field of view of 45mm, and a visible light band of 400nm to 700nm. While improving the detection efficiency of the optical system, it can also achieve flat-field apochromatic and perfect imaging.

[0140] While various embodiments of the present disclosure have been described above, the above descriptions are illustrative, non-exhaustive, and not intended to be limiting of the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable other persons skilled in the art to understand the embodiments disclosed herein.

Claims

1. An optical system, characterized in that: include: A microscope objective lens (Obj) and a tube lens (TL) are sequentially arranged along the optical axis from the object side to the image side, wherein the microscope objective lens (Obj) comprises a first lens group (G1), a second lens group (G2), a stop (STOP), and a third lens group (G3) sequentially arranged along the optical axis; The first lens group (G1) has positive power and is used to correct at least spherical aberration, astigmatism and axial chromatic aberration. The first lens group (G1) includes a first cemented lens (B1), a third lens (L3) and a second cemented lens (B2). The first cemented lens (B1) includes a first lens (L1) and a second lens (L2) cemented together. The second cemented lens (B2) includes a fourth lens (L4) and a fifth lens (L5) cemented together. The second lens group (G2) has positive refractive power and is used to correct at least coma and distortion. The second lens group (G2) includes a sixth lens (L6) and a third cemented lens (B3). The third cemented lens (B3) includes a seventh lens (L7), an eighth lens (L8), and a ninth lens (L9) cemented in sequence. The third lens group (G3) has positive refractive power and is used to correct at least field curvature and vertical chromatic aberration. The third lens group (G3) includes a fourth cemented lens (B4), a thirteenth lens (L13), a fourteenth lens (L14), and a fifteenth lens (L15). The fourth cemented lens (B4) includes a tenth lens (L10), an eleventh lens (L11), and a twelfth lens (L12) cemented in sequence. The stop (STOP) is arranged between the third cemented lens (B3) and the fourth cemented lens (B4) to correct chromatic aberration by placing the third cemented lens (B3) and the fourth cemented lens (B4) on both sides of the stop (STOP); The tube lens (TL) has positive optical power and includes a fifth cemented lens (B5), a sixth cemented lens (B6) and a twenty-first lens (L21) arranged in sequence along the optical axis. The fifth cemented lens (B5) includes a sixteenth lens (L16) and a seventeenth lens (L17) cemented together. The sixth cemented lens (B6) includes an eighteenth lens (L18), a nineteenth lens (L19) and a twentieth lens (L20) cemented together in sequence.

2. The optical system according to claim 1, wherein the microscope objective lens (Obj) is an infinite conjugate objective lens, at least for imaging an object on the object side to infinity, and the tube lens (TL) is an infinite focusing lens, at least for imaging an object at infinity onto a detector on the image side.

3. The optical system according to claim 2, wherein the focal length of the tube lens (TL) is 200 mm.

4. The optical system according to claim 2, wherein the focal lengths of the first lens group (G1), the second lens group (G2), and the third lens group (G3) satisfy: 1.0<|f1 / f|<2.0, 1.5<|f2 / f|<2.5, 7.0<|f3 / f|<8.0, in, f is the total focal length of the microscope objective lens (Obj), f1 is the focal length of the first lens group (G1), f2 is the focal length of the second lens group (G2), and f3 is the focal length of the third lens group (G3).

5. The optical system according to claim 4, wherein the object side of the first lens (L1) is concave, and the image side of the first lens (L1) is concave; The object side of the second lens (L2) is a convex surface, and the image side of the second lens (L2) is a convex surface; The object side of the third lens (L3) is a convex surface, and the image side of the third lens (L3) is a convex surface; The object side of the fourth lens (L4) is a concave surface, and the image side of the fourth lens (L4) is a concave surface; The object side of the fifth lens (L5) is a convex surface, and the image side of the fifth lens (L5) is a flat surface; The object side of the sixth lens (L6) is a concave surface, and the image side of the sixth lens (L6) is a convex surface; The object side of the seventh lens (L7) is a convex surface, and the image side of the seventh lens (L7) is a convex surface; The object side of the eighth lens (L8) is a concave surface, and the image side of the eighth lens (L8) is a concave surface; The object side of the ninth lens (L9) is a convex surface, and the image side of the ninth lens (L9) is a convex surface; The object side of the tenth lens (L10) is a convex surface, and the image side of the tenth lens (L10) is a concave surface; The object side of the eleventh lens (L11) is a convex surface, and the image side of the eleventh lens (L11) is a convex surface; The object side of the twelfth lens (L12) is a concave surface, and the image side of the twelfth lens (L12) is a concave surface; The object side of the thirteenth lens (L13) is concave, and the image side of the thirteenth lens (L13) is convex; The object side of the fourteenth lens (L14) is concave, and the image side of the fourteenth lens (L14) is convex; The object side of the fifteenth lens (L15) is a convex surface, and the image side of the fifteenth lens (L15) is a convex surface.

6. The optical system according to claim 4, wherein the first lens (L1) has negative optical power and a focal length in the range of -410 mm to -400 mm; The second lens (L2) has positive optical power and a focal length in the range of 20 mm to 30 mm; The third lens (L3) has positive refractive power and a focal length in the range of 40 mm to 50 mm; The fourth lens (L4) has negative optical power and a focal length in the range of -40 mm to -30 mm; The fifth lens (L5) has positive refractive power and a focal length in the range of 160 mm to 170 mm; The sixth lens (L6) has positive refractive power and a focal length in the range of 40 mm to 50 mm; The seventh lens (L7) has positive refractive power and a focal length in the range of 110 mm to 120 mm; The eighth lens (L8) has negative optical power and a focal length in the range of -55 mm to -45 mm; The ninth lens (L9) has negative optical power and a focal length in the range of -120 mm to -110 mm; The tenth lens (L10) has positive refractive power and a focal length in the range of 20 mm to 30 mm; The eleventh lens (L11) has negative optical power and a focal length in the range of -20 mm to -10 mm; The twelfth lens (L12) has negative optical power and a focal length in the range of -25 mm to -15 mm; The thirteenth lens (L13) has negative optical power and a focal length in the range of -20 mm to -10 mm; The fourteenth lens (L14) has positive refractive power and a focal length in the range of 55 mm to 65 mm; The fifteenth lens (L15) has positive refractive power and a focal length within a range of 110 mm to 120 mm.

7. The optical system according to claim 2, wherein the focal lengths of the first lens group (G1), the second lens group (G2), and the third lens group (G3) satisfy: 0.5<|f1 / f|<1.5, 1.3<|f2 / f|<2.3, 1.0<|f3 / f|<2.0, in, f is the total focal length of the microscope objective lens (Obj), f1 is the focal length of the first lens group (G1), f2 is the focal length of the second lens group (G2), and f3 is the focal length of the third lens group (G3).

8. The optical system according to claim 7, wherein the object side of the first lens (L1) is concave, and the image side of the first lens (L1) is concave; The object side of the second lens (L2) is a convex surface, and the image side of the second lens (L2) is a convex surface; The object side of the third lens (L3) is a convex surface, and the image side of the third lens (L3) is a convex surface; The object side of the fourth lens (L4) is a concave surface, and the image side of the fourth lens (L4) is a concave surface; The object side of the fifth lens (L5) is a convex surface, and the image side of the fifth lens (L5) is a flat surface; The object side of the sixth lens (L6) is a flat surface, and the image side of the sixth lens (L6) is a convex surface; The object side of the seventh lens (L7) is a convex surface, and the image side of the seventh lens (L7) is a convex surface; The object side of the eighth lens (L8) is a concave surface, and the image side of the eighth lens (L8) is a concave surface; The object side of the ninth lens (L9) is a convex surface, and the image side of the ninth lens (L9) is a convex surface; The object side of the tenth lens (L10) is a convex surface, and the image side of the tenth lens (L10) is a concave surface; The object side of the eleventh lens (L11) is a convex surface, and the image side of the eleventh lens (L11) is a convex surface; The object side of the twelfth lens (L12) is a concave surface, and the image side of the twelfth lens (L12) is a flat surface; The object side of the thirteenth lens (L13) is concave, and the image side of the thirteenth lens (L13) is convex; The object side of the fourteenth lens (L14) is concave, and the image side of the fourteenth lens (L14) is convex; The object side of the fifteenth lens (L15) is a convex surface, and the image side of the fifteenth lens (L15) is a convex surface.

9. The optical system according to claim 7, wherein the first lens (L1) has negative optical power and a focal length in the range of -60 mm to -50 mm; The second lens (L2) has positive optical power and a focal length in the range of 20 mm to 30 mm; The third lens (L3) has positive refractive power and a focal length in the range of 30 mm to 40 mm; The fourth lens (L4) has negative optical power and a focal length in the range of -30 mm to -20 mm; The fifth lens (L5) has positive refractive power and a focal length in the range of 300 mm to 310 mm; The sixth lens (L6) has positive refractive power and a focal length in the range of 45 mm to 55 mm; The seventh lens (L7) has positive refractive power and a focal length in the range of 190 mm to 200 mm; The eighth lens (L8) has negative optical power and a focal length in the range of -70 mm to -60 mm; The ninth lens (L9) has negative optical power and a focal length in the range of -85 mm to -75 mm; The tenth lens (L10) has positive refractive power and a focal length in the range of 20 mm to 30 mm; The eleventh lens (L11) has negative optical power and a focal length in the range of -20 mm to -10 mm; The twelfth lens (L12) has negative optical power and a focal length in the range of -45 mm to -35 mm; The thirteenth lens (L13) has negative optical power and a focal length in the range of -20 mm to -10 mm; The fourteenth lens (L14) has positive refractive power and a focal length in the range of 45 mm to 55 mm; The fifteenth lens (L15) has positive refractive power and a focal length within a range of 105 mm to 115 mm.

10. The optical system according to claim 2, wherein the focal lengths of the first lens group (G1), the second lens group (G2), and the third lens group (G3) satisfy: 0.9<|f1 / f|<1.9, 5.5<|f2 / f|<6.5, 18.0<|f3 / f|<19.0, in, f is the total focal length of the microscope objective lens (Obj), f1 is the focal length of the first lens group (G1), f2 is the focal length of the second lens group (G2), and f3 is the focal length of the third lens group (G3).

11. The optical system according to claim 10, wherein the object side of the first lens (L1) is concave, and the image side of the first lens (L1) is convex; The object side of the second lens (L2) is a concave surface, and the image side of the second lens (L2) is a convex surface; The object side of the third lens (L3) is a convex surface, and the image side of the third lens (L3) is a concave surface; The object side of the fourth lens (L4) is a convex surface, and the image side of the fourth lens (L4) is a concave surface; The object side of the fifth lens (L5) is a convex surface, and the image side of the fifth lens (L5) is a concave surface; The object side of the sixth lens (L6) is a concave surface, and the image side of the sixth lens (L6) is a convex surface; The object side of the seventh lens (L7) is a convex surface, and the image side of the seventh lens (L7) is a convex surface; The object side of the eighth lens (L8) is a concave surface, and the image side of the eighth lens (L8) is a concave surface; The object side of the ninth lens (L9) is a convex surface, and the image side of the ninth lens (L9) is a convex surface; The object side of the tenth lens (L10) is a convex surface, and the image side of the tenth lens (L10) is a concave surface; The object side of the eleventh lens (L11) is a convex surface, and the image side of the eleventh lens (L11) is a convex surface; The object side of the twelfth lens (L12) is a concave surface, and the image side of the twelfth lens (L12) is a concave surface; The object side of the thirteenth lens (L13) is concave, and the image side of the thirteenth lens (L13) is convex; The object side of the fourteenth lens (L14) is concave, and the image side of the fourteenth lens (L14) is convex; The object side of the fifteenth lens (L15) is a convex surface, and the image side of the fifteenth lens (L15) is a convex surface.

12. The optical system according to claim 10, wherein the first lens (L1) has negative optical power and a focal length in the range of -40 mm to -30 mm; The second lens (L2) has positive optical power and a focal length in the range of 10 mm to 20 mm; The third lens (L3) has positive refractive power and a focal length in the range of 30 mm to 40 mm; The fourth lens (L4) has positive refractive power and a focal length in the range of 30 mm to 40 mm; The fifth lens (L5) has negative optical power and a focal length in the range of -50 mm to -40 mm; The sixth lens (L6) has positive refractive power and a focal length in the range of 60 mm to 70 mm; The seventh lens (L7) has positive refractive power and a focal length in the range of 100 mm to 110 mm; The eighth lens (L8) has negative optical power and a focal length in the range of -45 mm to -35 mm; The ninth lens (L9) has negative optical power and a focal length in the range of -120 mm to -110 mm; The tenth lens (L10) has positive refractive power and a focal length in the range of 10 mm to 20 mm; The eleventh lens (L11) has negative optical power and a focal length in the range of -15 mm to -5 mm; The twelfth lens (L12) has negative optical power and a focal length in the range of -15 mm to -5 mm; The thirteenth lens (L13) has negative optical power and a focal length in the range of -15 mm to -5 mm; The fourteenth lens (L14) has positive refractive power and a focal length in the range of 55 mm to 65 mm; The fifteenth lens (L15) has positive refractive power and a focal length within a range of 90 mm to 100 mm.

13. The optical system according to claim 3, wherein the object side of the sixteenth lens (L16) is convex, and the image side of the sixteenth lens (L16) is convex; The object side of the seventeenth lens (L17) is concave, and the image side of the seventeenth lens (L17) is convex; The object side of the eighteenth lens (L18) is a convex surface, and the image side of the eighteenth lens (L18) is a concave surface; The object side of the nineteenth lens (L19) is a convex surface, and the image side of the nineteenth lens (L19) is a concave surface; The object side of the 20th lens (L20) is a convex surface, and the image side of the 20th lens (L20) is a flat surface; The object side of the twenty-first lens (L21) is a flat surface, and the image side of the twenty-first lens (L21) is a concave surface.

14. The optical system according to claim 13, wherein the sixteenth lens (L16) has negative optical power and a focal length in the range of -310 mm to -300 mm; The seventeenth lens (L17) has positive refractive power and a focal length in the range of 350 mm to 360 mm; The eighteenth lens (L18) has positive refractive power and a focal length in the range of 80 mm to 90 mm; The nineteenth lens (L19) has positive refractive power and a focal length ranging from 1340 mm to 1350 mm; The twentieth lens (L20) has positive refractive power and a focal length within a range of 5790 mm to 5800 mm. The twenty-first lens (L21) has negative optical power and a focal length within a range of -70 mm to -60 mm. 15 . The optical system according to claim 1 , wherein a diameter of the stop (STOP) comprises one of 12 mm and 8 mm. The optical system according to claim 1 , wherein an operating wavelength band of the optical system includes 400 nm-700 nm.

17. The optical system according to claim 1, wherein a distance between an object-side surface of the first lens (L1) and an object is in a range of 7.0 mm to 13.0 mm.

18. The optical system according to claim 1, wherein a front entrance pupil distance of the tube lens (TL) is in the range of 100.0 mm to 210.0 mm, and a back working distance of the tube lens (TL) is in the range of 150.0 mm to 151.0 mm.

19. The optical system according to claim 1, wherein the first lens (L1), the second lens (L2), the third lens (L3), the fourth lens (L4), the fifth lens (L5), the sixth lens (L6), the seventh lens (L7), the eighth lens (L8), the ninth lens (L9), the tenth lens (L10), the eleventh lens (L11), the twelfth lens (L12), the thirteenth lens (L13), the fourteenth lens (L14), the fifteenth lens (L15), the sixteenth lens (L16), the seventeenth lens (L17), the eighteenth lens (L18), the nineteenth lens (L19), the twentieth lens (L20) and the twenty-first lens (L21) are standard spherical lenses.

20. A microscope, characterized in that: include: An optical system according to any one of claims 1 to 19. 21 . The microscope according to claim 20 , further comprising a first optical element arranged between the microscope objective (Obj) and the tube lens (TL), and / or a second optical element arranged between the tube lens (TL) and an image-side detector.

22. The microscope of claim 21, wherein the first optical element comprises at least one of a dichroic mirror, a filter, and a prism, and the second optical element comprises at least one of a beam splitter and a filter.

Images